NASA/TP-2004-2 1 2254 

INTERNATIOI 

OR GEODESY 

Edited by 

N.R. Vandenberg 

and K.D. Baver 

IVS Coordinating Center 

February 2004 
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The cover image depicts the VLBl concept of the near future: broad-spectrum white noise from quasars is recorded at radio 

telescopes and iransmitted via high speed data links to a correlator. 
Preface 

This volume of reports is the 2003 Annual Report of the International VLBI Service for Geodesy 

and Astrometry (IVS). The individual reports were contributed by VLBI groups in the international geodetic and astrometric community who constitute the permanent components of IVS. 

The IVS 2003 Annual Report documents the work of the IVS components for the calendar year 

2003, our fifih year of existence. The reports describe changes, activities, and progress of the IVS. 

Many thanks to all IVS components who contributed to this Annual Report. 

The entire contents of this Annual Report also appear on the IVS web site at 

http://ivscc.gsfc.nasa.gov/publications/ar2OO3 

This book and the web site are organized as follows: 

0 The first section contains general information about IVS, a map showing the location of the 

components, information about the Directing Board members, and the annual report of the 

IVS Chair. 

0 The next seven sections hold the reports from the Coordinators, and the reports from the IVS 

Permanent Components: Network Stations, Operation Centers, Correlators, Data Centers, 

Analysis Centers, and Technology Development Centers. 

0 The last section includes reference information about IVS: the Terms of Reference, the lists 

of Member and Affiliated organizations, the IVS Associate Member list, a complete list of 

IVS components, the list of institutions contributing to this report, and a list of acronyms. 

iii 
Table of Contents 

... Preface ............................................................................................... rn 

About IVS ......................................................................... 1 

IVS Organization ..................................................................................... 2 

NS Component Map ................................................................................. -4 

IVS Directing Board .................................................................................. 6 

IVS Chair’s Report .................................................................................... 8 

IVS Coordination ................................................................ 11 

Coordinating Center Report ......................................................................... -13 

Analysis Coordinator Report ........................................................................ -16 

Network Coordinator Report ......................................................................... 18 

IVS Technology Coordinator Report .................................................................. 23 

Network Stations ................................................................ 27 

Algonquin Radio Observatory ........................................................................ 29 

Fortaleza Station Report for 2003 .................................................................... 32 

Gilmore Creek Geophysical Observatory .............................................................. 35 

Goddard Geophysical and Astronomical Observatory ................................................ -38 

Hartebeesthoek Radio Astronomy Observatory (HartRAO) ........................................... 41 

Hobart, Mt . Pleasant, Station Report for 2003 ...................................................... -45 

Kashima 34m Radio Telescope ....................................................................... 47 

Kashima and Koganei 11-m VLBI Stations .......................................................... -51 

Kokee Park Geophysical Observatory ................................................................. 55 

Matera CGS VLBI Station ........................................................................... 59 

The Medicina Station Status Report ................................................................ -63 

Noto Station Activity ................................................................................ 67 

NYAL Ny-Alesund 20 Metre Antenna ................................................................ 69 

German Antarctic Receiving Station (GARS) O’Higgins .............................................. 72 

The IVS Network Station Onsala Space Observatory ................................................. 76 

Sheshan VLBI Station Report for 2003 ............................................................... 80 

“Sieiz-Katsively” Geodynamic Area: Results of the Geodetic VLBI Observing Program and Variability 

of the Black Sea Level ................................................................................ 83 

Svetloe Radio Astronomical Observatory ............................................................. 87 

Geodetic Observatory TIGO in Concepcih ......................................................... -90 

Tsukuba 32-m VLBI Station ......................................................................... 94 

Westford Antenna .................................................................................... 98 

Fundamentalstation Wettzell - 20m Radiotelescope ................................................. -102 

Observatorio Astron6mico Nacional - Yebes ......................................................... 106 

Yellowknife Observatory ............................................................................ 109 

Operation Centers ............................................................. 111 

The Bonn Geodetic VLBI Operation Center ......................................................... 113 

CORE Operation Center Report .................................................................... 115 

U.S. Naval Observatory Operation Center ........................................................... 118 

V 
Correlators ...................................................................... 119 

The Bonn Astro/Geo Mark IV Correlator ........................................................... 121 

Haystack Observatory VLBI Correlator ............................................................. 125 

IAA Correlator Center .............................................................................. 128 

Kashima VLBI Correlators .......................................................................... 132 

Tsukuba VLBI Correlator ........................................................................... 136 

Washington Correlator .............................................................................. 140 

Data Centers 143 

BKG Data Center 145 

................................................................... 

.................................................................................. Data Center at Communications Research Laboratory ............................................... 147 

CDDIS Data Center Summary for the 2003 IVS Annual Report ..................................... 151 

Italy CNR Data Center Report ..................................................................... 154 

Paris Observatory (OPAR) Data Center ............................................................. 156 

Analysis Centers ............................................................... 159 

Analysis Center of Saint-Petersburg University ...................................................... IUI 

Geoscience Australia Analysis Center ............................................................... 163 

Bordeaux Observatory Analysis Center Report ...................................................... 166 

Matera CGS VLBI Analysis Center ................................................................. 170 

Analysis Center at Communications Research Laboratory ........................................... 172 

DGFI Analysis Center Annual Report 2003 ......................................................... 176 

FFI Analysis Center ................................................................................ 179 

The GIUB/BKG VLBI Analysis Center ............................................................. 180 

GSFC VLBI Analysis Center ........................................................................ 184 

MIT Haystack Observatory Analysis Center Report ................................................. 188 

IAA VLBI Analysis Center Report 2003 ............................................................. 191 

Italy CNR Analysis Center Report .................................................................. 195 

Vienna IGG Special Analysis Center Annual Report 2003 ........................................... 197 

JPL VLBI Analysis Center IVS Annual Report for 2003 ............................................. 201 

Paris Observatory Analysis Center-OPAR Report on Activities, January - December 2003 .......... 207 

The IVS Analysis Center at the Onsala Space Observatory .......................................... 211 

Shanghai Astronomical Observatory Analysis Center Report ........................................ 215 

US . Naval Observatory VLBI Analysis Center ...................................................... 219 

USNO Analysis Center for Source Structure Report ................................................. 223 

Technology Development Centers ............................................ 227 

Canadian VLBI Technology Development Center .................................................... 229 

Technology Development Center at CRL ............................................................ 232 

FFI Technology Development Center . Software Development ....................................... 236 

GSFC Technology Development Center Report ...................................................... 238 

Haystack Observatory Technology Development Center .............................................. 241 

Institute of Applied Astronomy Technology Development Center .................................... 245 

The IVS Technology Development Center at the Onsala Space Observatory .......................... 249 

*e, 

IVS Analysis Center at Main Astronomical Observatory of National Academy of Sciences of Ukraine 205 

vi 

. 
IVS Information ................................................................ 253 

NS Terms of Reference ............................................................................. 255 

NS Member Organizations ......................................................................... 265 

NS Affiliated Organizations ........................................................................ 266 

NS Associate Members ............................................................................. 267 

NS Permanent Components ....................................................................... -277 

Addresses of Institutions of Authors Contributing to this Report .................................... 281 

List of Acronyms .................................................................................... 287 

vii 

IVS ORGANIZATION 

OBJECTIVES 

IVS is an international collaboration of organizations 

which operate or support Very Long Baseline Interferometry (VLBI) components. The goals are: 

To provide a service to support geodetic, 

geophysical and astrometric research and operational activities. 

To promote research and development activities 

in all aspects of the geodetic and astrometric VLBl 

technique. 

To interact with the community of users of VLBl 

products and to integrate VLBl into a global Earth 

observing system. 

The NS 0 

0 

0 

0 

0 

0 

0 

2 

Interacts closely with the IERS, which is tasked by 

IAU and IUGG with maintaining the international 

celestial and terrestrial reference frames (ICRF 

and ITRF), 

coordinates VLBl observin programs, 

establishes conventions for data formats and 

products, 

issues recommendations for analysis software, 

sets standards for analysis documentation, 

institutes appropriate product delivery methods in 

order to insure suitable product quality and timeliness. 

sets performance standar B s for the observing stations, 

REALIZATION AND STATUS OF IVS 

IVS consists of 

29 Network Stations, acquiring high performance 

VLBl data, 

3 Operation Centers, coordinating the activities of a 

network of Network Stations, 

6 Correlators, processing the acquired data, providing feedback to the stations and providing processed 

data to analysts, 

6 Data Centers, distributing products to users, 

providing storage and archiving functions, 

21 Anal sis Centers, analyzing the data and producing Je results and products, 

7 Technology Development Centers, developing new 

VLB I tech nolog y, 

1 Coordinating Center, coordinating daily and long 

term activities. 

AI together 

73 Permanent Components, representing 37 institutions in 17 countries, 

-250 Associate Members. 

In addition the NS has: 

Directing Board, determining policies, standards 

and goals; the board is composed of 15 members 

(elected and ex officio), including 

Coordinators for the network, analysis 

and technology. 

ORGANIZATION OF INTERNATIONAL VLBl SERVICE 

"k 

Olc 

Coordinator a"" 

Operation 

1 UdiOllS Coordinating 

Centor 

. Publications 

. w.b Si10 

Mask Schedule 
IVS MEMBER ORGANIZATIONS 

The following organizations contribute to NS by wpporting one or me IVS components. They are considered 

IVS Members. Listed alphabetically by country. 

Geoscience Austmlia Australia 

Universitv of Tasmania Australia 

Main Astronomical Observatory, 

Ukraine 

Laboratory of Radioastronomy 

Ukraine 

NASA Goddard Space Flight Center USA 

Jet Propulsion Labomtory USA 

National Academy of Sciences, Kiev 

of Crimean Astrophys ical Observ60ry 

U. S. Naval Obsmmtory USA 

Vienna Universitv ot Mndoav Austria 

Centro de Radio Astronomia e 

Aplicq6es Espaciais Brazil 

Space Geodyna mics laboratory Canada 

Geodetic Survey Division, 

Natural Resources Canada Canada 

Dominion Radio Astrophysical 

Observatory Canada 

Canadian Space Agency Canada 

Universidad de Concemih Chile 

Universidad del Bio Bib 

Universidad Catolica de la 

Santisima Conccmih 

Chile 

Chile 

lnstiiuto GeoamDhicd Militar of Chile Chile 

Chinese Academy ot Sciences China 

Observotoire de Pans France 

Obsewatoire de Bordeaux France 

DeukhesGeodijti~ 

Bundesamt fiir Kartographie 

und Geodiisie 

Geodetic Institute of the University 

Forxhungse-nrichtung Satellitendie, 

Forxhungsinstitut -nY 

of Bonn +nY 

_ - 

TU-Munich GemKlny 

lstituto di Radioastronmia CNR ltalv 

Agenzia Spaziale ltaliana kl; 

Geographical Survey Institute Japan 

Communications R&r& la born^ 6 

National Astronomid Observatory 

of Jmn Jam r- -- 

National ‘Institute of Polar Research 

Norwegian Defence Research 

Japan 

Establishment Norway Norwegian Mapping Authm’ty Norway 

Astronomical Institute of 

St.-Petersburg university Russia 

Institute of Applied Astronomy Russia 

Hartebeesthoek Radio Astronomy 

Obserwtory SouthAfrica 

lnstituto Geog rafico Nacional Spain 

Chalmers University of Technology Sweden 

IVS AFFILIATED ORGANIZATIONS 

The following organizations cooperate with IVS on issues 

of common interest, but do not support an NS comrFt. 

Affiliated Organizations express an interest in esta lishing 

and maintaining a strong worki association with IVS to 

mutual benefit. Listed alphabetica 7 ly by country. 

Austmlian National University AUStIUlia 

University of New Brunswick Canada 

Max-Plonck-lnstitut fiir Radioashnomie Germany 

satellite Geodetic observatory -- ry 

Korea Astronornyobservatory Korea 

Joint Institute for VLBl in Europe (JIVE) NE!lhdCd 

Wes~ob~atiny Nt3IhddS 

Central (Pulkovo) Astronomical Observatory Russia 

National Radio Astronomy Observatory USA 

PRODUCTS 

l%e VLBl technique contributes uniquety to 

Definition and realization of he International Celestial Reference Frame (ICRF) 

Moniton’ng of Universal Time (UTI ) and length 

of day (LOD) 

Moniton’ng the coordinates of the celestial pole 

(nutation and precession) 

Further significant products are 

Stotion coordinates and veloci vectors for the 

All components of Earth Orientation Parameters at 

regular intervals 

realization and maintenance $the International 

lkrrestrial Refeme Frame (ITRF) 

All VLBl dato and resutk in 

chived in dato centers and 

in related areas of geodesy, 

httpd/’wscc.gsfc.nar.gov 

formats are arsics and astrcnnetry. 

for research 

3 
IVS COMPONENTS BY 

COUNTRY 

Audia 

Austria 

Bradl 

con& 

Chile 

China 

FlUnCe 

-Y [fob 

Japan 

Norway 

Russia 

South Africa 

Spain 

Sweden 

Ukraine 

USA 

Tofol 

A com~lete list of NS Permanent 

~oqinents is in the NS Information 

se~h'on of his volume. 

IVS COMPONENT MAP 

2 

1 

1 

3 

1 

3 

3 

8 

7 

12 

3 

5 

1 

1 

3 

2 

17 

73 

- 

7 

4 
C 

.- 

.. , * f' 

I 

4 

i 1--- 

s 

L s-, 

r 

J 

i; 

i 

i J 

5 
IVS DIRECTING BOARD 

NAME: Wolfgang Schluter 

AFFILIATION: Bundesamt fur 

Kartographie und Geodasie, 

Germany 

POSITION: Chair and Networks 

Representative 

TERM: Feb 2003 to Feb 2007 

I 

NAME: Ed Himwich 

AFFILIATION: NVI, Inc./ 

Goddard Space Flight Center, 

USA 

POSITION: Network 

Coordinator 

TERM: permanent 

71 NAME: Kerry Kingham 

NAME: ChopoMa 

AFFILIATION: NASA GOdLJrc 

Space Flight Center, USA 

1 W-J I POSITION: IERS Representative 

TERM: exofficio 

-1 NAME: Zinovy Malkin 

AFFILIATION: U.S. Naval 

Observatory, USA Applied Astronomy, Russia 

POSITION: Correlaton 

and Operation Centers 

Representative 

TERM: Feb 2003 to Feb 2007 

AFFILIATION: Institute of 

POSITION: Analysis and Data 

Centers Representative 

TERM: Sept 2003 to Feb 2005 

I NAME: YasuhiroKoyama 

I AFFILIATION: Communications 

Research Laboratory, Japan 

POSITION: At Large Member 

TERM: Feb 2001 to Feb 2005 

I I 

NAME: Franco Mantovani 

AFFILIATION: CNR Bologna, 

POSITION: At Large Member 

TERM: Sept 2003 to Feb 2005 

Italy 
1 NAME: Shigeru Matsuzaka 

AFFILIATION: Geographical 

Survey Institute, Japan 

POSITION: Networks 

Representative 

TERM: Feb 2003 to Feb 2007 

NAME: Arthur Niell 

AFFILIATION: Haystack 

Observatory, USA 

POSITION: Techology beloprnent Centers Representative 

TERM: Feb 2001 to Feb 2005 

NAME: Axel Nothnagel 

AFFILIATION: University of 

Bonn, Germany 

POSITION: Analysis 

Coordinator 

TERM: permanent 

NAME: William Petrachenko 

AFFILIATION : No tiona I 

Resources Canada, Canada 

POSITION: At Large Member 

TERM: Feb 2003 to Feb 2005 

NAME: Harold Schuh 

AFFILIATION: Vienna University 

of Technology, Austria 

POSITION: IAG Representative 

TERM: exofficio 

NAME: Patrick Wallace 

AFF I Ll ATlON : Rutherford 

Appleton Laboratory, UK 

POSITION: IAU Represer 

TERM: exofficio 

NAME: Alan Whitney 

AFFILIATION: Haystack 

Observatory, USA 

POSITION: Technology 

Coordinator 

TERM: permanent 

itative 

7 
IVS CHAIR'S REPORT 

Wolfgang Schluter 

Bundesamt fiir Kartographie und Geodasie, Germany 

Reviewing the last years, it is notable that the International 

VLBl Service for Geodesy and Astrometry (IVS) is now 

fulfilling its role as a service within the IAG by providing 

important products for the maintenance of global reference frames (ITRF, ICRF and EOP's). IVS is providing time 

series that are timely and precise and it has established 

observing programs and procedures to meet the current 

requirements as best as the resources allow. IVS uniquely 

provides the parameters for the CRF, a complete set of 

the Earth rotation parameter and in particular the DUTl 

parameter. Those products can be regarded as a basic infrastructure and are essential for research in fields related 

to the Earth and to space as well as for applications such 

as navigation and geodesy which make use of global 

reference frames. IVS is dependent on the contributions of 

its members and member institutions which proposed their 

support by their responses to the original call for participation. IVS is coordinating and optimizing the available 

resources as much as possible aiming to increase the 

efficiency and the quality of the products. 

With great respect I appreciate the effort and the contributions from all IVS Permanent Components - from the 

Network Stations, the Operation Centers, the Correlators, the Analysis Centers, the Data Centers, the Technology Development Centers and last but not least from the 

Coordinating Center. I express my sincere thanks to all 

members and member institutions for the strong support 

during 2003. In particular I thank the IVS Coordinators 

Axel Nothnagel, Ed Himwich, and Alan Whitney for their 

strong engagement as well as Nancy Vandenberg as 

Director of the Coordinating Center and as chair of the 

Observing Program Committee. 

Considering that financial resources throughout our community have been reduced, I feel the responsibility to express my concern. I would like to emphasize that the most 

effective generation of the IVS products could only be 

done through international collaboration. This is the way 

all the IAG services are working - namely all collaborating agencies contribute according to their resources, and 

in return all benefit from the results and products, which 

never could be achieved by a single institution. I'm aware 

that this kind of organization is very sensitive to any 

reduction from collaborating partners but to keep these 

highly qualified products at low cost, it requires the long 

term continuous support which is in the responsibility of 

all members and member institutions. 

Progress in 2003 

The most significant progress in 2003 came from employment of the disk-based digital data recording systems Mark 

5 and K5, which allow us to handle the large amount of 

VLBl raw data at lower cost and with more reliability. The 

digital data recorders are the basis for the development 

of e-VLBI. It also has to be pointed out that the work at the 

correlator has improved significantly and the correlation 

procedure, in particular the recorrelation, can now be 

done faster. The transition from Mark 4 to Mark 5A is being performed smoothly, and most of the observing stations 

and the correlators are now equipped with disk-based 

digital recorders. 

Further developments have been carried out for the VLBl 

Standard Interface (VSI). Hardware has been built and the 

VSI software interface was released, which is very important for the combination of the different recording techniques. The Mark 5B recording systems are being developed, which will result in a step forward, as formatters will 

become obsolete, he problems with the Mark 4 correlator 

station units will be overcome, and compatibility of the 

technology will be supported by the integration of VSI. 

The Pilot Project "Tropospheric Parameters", led by the 

University of Vienna was carried out successfully and was 

turned over to a regular service product. The tropospheric 

parameters were accepted as an official IVS product at the 

9th Directing Board Meeting. 

A pew Pilot Project, led by the Analysis Coordinator Axel 

Nothnagel, "Time Series of Station Coordinates and 

Baseline Lengths", has been set up, which is a first step 

in the provision of regular baseline lengths. Such a time 

series will be useful for many investigations of periodic and 

aperiodic variations caused by geophysical phenomena. 

The board established its third Working Group, chaired 

by Alan Whitney and Arthur Niell, which is tasked to 

develop a vision for VLBl in 201 0. It has to be considered 

hat many components have been used in VLBl for some 

decades and urgently need an upgrade or even replacement. A lot of technical improvements will have to be 

integrated into a new VLBl generation and some upcoming 

problems, such as the interference in S-band, need a solution. A report from the VLB12010 Working Group should 

be made available in 2004 which will become a guideline 

for the establishment of the next VLBl generation and will 

support the establishment of joint developments, in order to 

decrease development costs. 

8 
Key events in 2003 

In 2003 we had some IVS technical meetings: the 4th 

Analysis Workshop at Paris Observatory held April 4-5, 

2003, the 16th European VLBl Meeting in Leipzip, in May, 

2004, and the Technical Operations Workshop (TOW) 

was held in Dwingeloo iointly with the EVN. These meetings are of importance to promote progress and to support 

the exchange of experiences. I highly appreciate the good 

documentation of these meetings e.g. through the publication of proceedings and their fast ap 

which cover the costs. 

t held at Haystack in September, 2004. An e-VLBI workshop 

rance after the 

meetings. Thanks to the editors but a I= so to the agencies 

It was a great surprise for me when Harald Schuh informed us with an e-mail that a team of European scientists 

coordinated by Prof. Dr. Veronique Dehant was one of two 

winners of the Decartes Prize 2003 for the project titled 

"Nutation". The Decartes Prize is the highest award for 

event as VLBl rovides the important measurements and 

and the control of the nutation model. With great respect 

for the group I express my appreciation and I congratulate 

them for such a wonderful success. 

I science in Europe. The IVS community can be proud of this 

products whic R are precise enough for the improvement 

1 

Changes in the Directing Board 

At the beginning of 2003 the first four-year terms ended 

for the elected board members Kerry Kingham from the 

US. Naval Observatory representing the Correlators and 

Operation Centers, Shigeru Matsuzaka from Geographical 

Survey Institute/Ja n and myself representing the Netmembers Wayne Cannon, Space Geodetic Laboratory/ 

Canada and Paolo Tomasi, CNR Bologna/ltaly. The election for the next four-year term resulted in the re-election 

of Kerry Kingham, Shigeru Matsuzaka, and myself. The 

board elected William Petrachenko, National Resources 

Canada and Zinovy Malkin, Institute for Applied Astromomy, St. Petersburg/Russia as new at large members 

- following the TOR - for two-year terms. 

For Nicole Capitaine, Paris Observator /France her term 

ford Appleton Laboratory/Chilton-UK was appointed by 

IAU to take over her position. 

At its 9th meeting the board elected the new chair. It is a 

great honor for me being elected for the second time and 

1 would like to express my thanks to the Associate Members and to the board members for their demonstration 

work Stations, an r also the terms ended for the at large 

as IAU representative ended and Patric I Wallace, Rutherof confidence. With pleasure I want to congratulate the 

re-elected, the elected and the nominated board members. 

I'm convinced that the new board will continue the work 

with fairness, balance, and enthusiasm, and will meet all 

the challenges of the future for IVS. 

I thank Nicole Capitaine, Wayne Cannon and Paolo Tomasi for their important contributions, for their support and 

strong engagement during the first four years. 

At the loth Directing Board Meeting James Campbell, 

University of Bonn/Germany withdrew as representative of 

the IAG and Harald Schuh, University of Vienna/Austria 

was ap inted by IAG as its representative. The board 

decidXo a point Zinovy Malkin to replace Harald as 

Analysis antfData Centers representative and then elected 

Franco Mantovani, CNR Bologna/ltaly for the open at 

large position. 

I thank James Campbell, one of the pioneers in VLBI, for 

his contributions to the VLBI community, as chair of the 

CSTG Commission that helped to shape the IVS, and of 

course for his work as chair of the Steering Committee that 

formed the IVS. My congratulations to Franco Mantovani 

on his election. He represents not only a major contributing 

institution but also gives a voice for the related group of 

radio astronomers. 

It has to be mentioned that Harald Schuh became a member of the newly established IAG Executive Committee. He 

was elected as one of the three service representatives. 

Chopo Ma, Goddard Space Flight Center/Greenbelt-USA 

was elected as one of the three service representatives 

in IAG Commission 1 (Reference Frames). Chopo Ma 

and I have been nominated as members of the Planning 

Group for IGGOS (Integrated Global Geodetic Observing 

System) - the IAG pilot project. It is of importance for IVS 

to have representatives on all these IAG Committees. M 

con ratulations to Harald %huh and to Chopo Ma an Cr 

my ti? st wishes for successful and effective service on the 

com m ittees. 

Thanks 

Again we can state that in 2003 IVS members have been 

very active and as result we had a successful year. I thank 

all members for their important contributions and for 

carrying out the additional work load in working groups, 

committees, for the preparation of presentations at various 

conferences, for writing reports etc. I would also express 

my gratitude to the member agencies for their important 

and strong support of IVS, which finally allows the members to make IVS into a living service. 

9 

NASA Goddard Space Flight Center IVS Coordinating Center 

Coordinating Center Report 

Nancy R. Vandenberg 

Abstract 

This report summarizes the activities of the IVS Coordinating Center during the year 2003, and 

forecasts activities planned for the year 2004. 

1. Coordinating Center Operation 

The IVS Coordinating Center is based at Goddard Space Flight Center and is operated by 

NEOS (National Earth Orientation Service), a joint effort for VLBI by the U.S. Naval Observatory 

and NASA Goddard Space Flight Center. 

The mission of the Coordinating Center is to provide communications and information for 

the IVS community and the greater scientific community and to coordinate the day-teday and 

long-term activities of IVS. 

The web server for the Coordinating Center is provided by Goddard. The address is 

http://ivscc .gsf c.nasa.gov 

2. Activities During 2003 

During the period from January through December 2003, the Coordinating Center supported 

the following IVS activities: 

Directing Board support: Coordinated two IVS Directing Board meetings, at Paris Observatory, France, (April 2003) and at Haystack Observatory, USA (October 2003). Notes fiom 

each meeting were published on the IVS web site. 

Communications support: Maintained the IVS web site, e-mail lists, and webbased mail 

archive files. Set up a new e-mail system using the Mailman facility, which eliminated the 

spread of spam on the IVS mail lists. Coordinated the team that developed a new structure 

and design for the web site (see next section). 

Publications: Published the 2002 Annual Report in spring 2003. Published three editions 

of the IVS Newsletter in April, August, and December, 2003. All publications are available 

electronically as well as in print form. 

2003 Master Schedule: Generated and maintained the master observing schedule for 2003. 

Coordinated VLBI resources for observing time, correlator usage, tapes and disk modules. 

Coordinated the introduction and usage of Mark 5 systems at IVS stations. 

2004 Master Schedule: Generated the proposed master schedule for 2004 and received ap 

proVal from the Observing Program Committee. 

Meetings: Coordinated, with the NRCan Local Committee, the third IVS General Meeting, 

held in Ottawa, Canada in February 2004. Chaired the Program Committee for the meeting. 

Observing Program Committee (OPC): Coordinated meetings of the OPC to monitor the 

observing program, review problems and issues, and discuss changes. 

IVS 2003 Annual Report 13 
IVS Coordinating Center NASA Goddard Space Flight Center 

3. Web Site Update 

During 2003 the IVS web site design was updated. Construction of the new site will be 

accomplished in early 2004. 

Ne&\ Mail CoiiLdcii Related Links Site Mdb L - - .- - 

International VLBI Service for Geodesy & Astrometry 

The Gods of Ns are: 

TO Provide service to supporl ae~ckr?tic, 

geophysical and astrumeti IC research 

and operational actlvBe5 

e TO interact wth the community of 'mere 

of VLEl products anatu integrate VLEl 

into a global Earth observing system 

* To promote research and deyeluprnent 

adivilief in all aspects of the geodetic 

and astranetrlc VLEl technique 

3rd General Meeting 

The third General Meeting wi!I be held in 3taoa Canada Februarv 9-1 1 , 1004 blah blah blah 

Thc: abstiad deadline is Dacembe- 1 , 2003 Reg,stratiun 13 open iuntil Januatv '3,2004 etc rti 

eto etc etc and so cn and on and on 

December Newsletter 

The Decetnher issue ut the NewsMel we5 released m December 3 

Call for 2003 Annual Report 

The call for submis?lons tu the 2003 Annual Rerurt H'aE sent via t-nedl to thy IVS mailing list 

Responeee are due blah hiah piah, severe and unpleasant penaities for being late will be 

mposed on nienibeic 

MORE NEWS AND EVENTS H 

Figure 1. New IVS home page. This image shows the design of the new IVS home page. Major topics 

are shown in the bar at the top of the image, useful links such as mail and search are at the top of the page. 

The content of the home page gives the main mission of IVS for new visitors to the site, as well as current 

news and events for regular visitors. 

The web site covers three main topics for IVS: activities, organization, and products. The site 

0 To provide a location on the web for IVS members and members of the scientific community 

to find data, products and general information provided by IVS. 

0 To act as a hub of information for IVS members. Since participants in the program are 

spread all over the world, the web site can act as a good resource to keep members informed 

of IVS activities. 

works to serve three main purposes: 

14 IVS 2003 Annual Report 
NASA Goddard Space Flight Center IVS Coordinating Center 

Name Title Responsibilities 

Nancy Vandenberg Director Web design and content, Directing 

0 To promote IVS and to educate the scientific community and other interested parties in the 

The new site has a clean design, improved navigation, and a revised structure that better 

reflects the needs of users. The structure was developed via discussions with a team consisting of 

Hayo Hase, BKG, Germany and Chile; Yasuhiro Koyama, CRL Kashima, Japan; Zinovy Malkin, 

Institute of Applied Astronomy, Russia; Dan Smythe, MIT Haystack Observatory, USA; Christoph 

Steinforth, University of Bonn, Germany; and Nancy Vandenberg, Coordinating Center Director. 

The design and construction of the new site was implemented by Doug League, RS Information 

Systems, of the NASA GSFC Technical Information Services Branch. 

work IVS is doing. 

Allocation 

50% 

4. Staff 

Board support, meetings, 

publicat ions 

Master schedule (current year), 

resource management, meetings and 

t Cynthia Thomas Operation 50% 

F'rank Gomez 

Karen Baver 

travel support, special sessions 

system maintenance, data center 

support, session processing scripts, 

mirror site liaison 

Web Manager Web server administration, mail 50% 

Publication Publication processing programs, 10% 

Programmer and 

Editor t Debra Gonzalez Data Technician 

Latex support and editorial 

assistance 

Master schedules, resource 

monitoring, session web pages 

monitoring 

5. Plans for 2004 

The Coordinating Center plans for 2004 include the following: 

0 Support the new IVS web site and implement new station pages. 

0 Publish the 2003 Annual Report (this volume). 

0 Publish Proceedings of the third IVS General Meeting. 

0 Support Directing Board meetings in 2004. 

0 Coordinate the 2004 master observing schedule and IVS resources. 

0 Publish Newsletter issues in April, August, and December. 

0 Publish an IVS color brochure. 

IVS 2003 Annual Report 15 
IVS Analysis Coordinator Geodatisches Institut der Universitat Bonn 

Analysis Coordinator Report 

A. Nothnagel, C. Steinforth 

Abstract 

IVS analysis coordination issues in 2003 are reported here. 

1. General Issues 

The “Fourth IVS Analysis Workshop” was held at Observatoire de Paris in Paris, France, 

April 3 - 4, 2003. Detailed information on the presentations and discussions can be found under 

ht tp://giub.geod.uni-bonn.de/vlbi/IVS-AC. 

2. IVS Operational Data Analysis and Combination 

2.1. Terrestrial Reference Frame 

In late 2002 it became evident that the ITRF2000 coordinates and velocities [l] of some of 

the VLBI stations regularly used in IVS-R1 and -R4 observing sessions did not match VLBI 

observations accumulated up to late 2002 [2]. Consequently the use of ITRF2000 as a fixed 

terrestrial reference frame (TRF) lead to significant distortions in some of the EOP series submitted 

by IVS Analysis Centers and in the combined IVS EOP series. In addition the site of GILCREEK 

(Fairbanks) was affected by an earthquake in October 2002. For these reasons a conventional 

VLBI terrestrial reference frame (VTRF2003) was developed with its axis and geocenter definition 

closely aligned to ITRF2000 but with modifications of some of the station coordinates and velocities 

(Nothnagel, 2003). 

2.2. IVS EOP Series 

Early in 2003 routine analysis and combination of the earth orientation parameters (EOP) 

series submitted by the six IVS Analysis Centers has seen a change with respect to the underlying 

terrestrial reference frame. Until the end of 2002 the combined EOP series were closely linked to 

the ITRF2000. Owing to the deficiencies of ITRF2000 listed above, VTRF2003 was used as the 

TRF for a consistent alignment of the TRF and the IVS EOP series. 

Since the end of 2003 a seventh series provided by Sergei Bolotin from the Main Astronomical 

Observatory Kiev, Ukraine, is regularly submitted to the IVS Data Centers. First comparisons 

with the combined series have been carried out. 

On January 1, 2003, the IAU2000 resolutions were planned to take effect. However, some of the 

numerical constants of the IAU2000 precession, nutation and non-rotating origin models had not 

been finalized early enough. Therefore, modifications in the VLBI analysis software packages for 

the IAU2000 resolutions had not yet been completed for a timely start of producing the new type 

of EOP. In order to provide celestial pole offsets in the new paradigm (X, Y) a conversion program 

was developed on the basis of software kindly provided by Christian Bizouard, Observatoire de 

Paris. Consequently, the rapid service EOP series (e. g. ivs03rle.eops) as well as the complete 

(since 1979) IVS series are routinely complemented by the files ivs03rlX.eops and ivsO3qlX.eops 

16 IVS 2003 Annual Report 
Geodtitisches Institut der Universitiit Bonn IVS Analysis Coordinator 

which contain celestial pole offsets (X, Y) instead of the classical nutation offset d$, dE w.r.t. to 

IAU1980. More details can be found in the proceedings of the Third IVS General Meeting, Ottawa, 

Canada, February 9 - 11, 2004. 

References 

[l] Altamimi, Z., P. Sillard, C. Boucher (2002): ITRF2OOO: A new release of the International 

Terrestrial Reference Fhme for earth science applications; JGR, Vol. 107, No. B10, 2214, 

doi:10.1029/2001 JB000561 

[2] Nothnagel A. (2003) V'TRF2003: A Conventional VLBI Terrestrial Reference hme; In: Proceedings of the 16th Working Meeting on European VLBI for Geodesy and Astrometry, held at Leipzig, 

May 09-10, 2003, edited by W. Schwegmann and V. Thorandt, Bundesamt fr Kartographie und 

Geodsie, FkankfUrt/Leipzig, 2003, p. 195-205 (web-reference: http://giub.geod.uni-bonn.de/vlbi/IVS 

AC /vtrf2003/vtrf2003.html). 

LVS 2003 Annual Report 17 
Network Coordinator NVI, Inc./GSFC 

Network Coordinator Report 

Ed Himwich 

Abstract 

This report includes an assessment of the network performance in terms of the yield of usable data 

over a 12 month period. A table of relative incidence of problems with various subsystems is presented. 

The current situation for the handlng of correlator clock adjustments by the correlators is reviewed. 

1. Network Performance 

The network performance report is based on correlator reports for sessions in calendar year 

2003. As of the date this report was generated, 188 sessions had been processed. There are another 

24 sessions from the calendar year that had not been processed yet, or the correlator results were 

not available. Most of the missing sessions are from the latter part of the year and/or are waiting 

for tapes from Antarctica before they can be processed. Roughly 85%-90% of the scheduled station 

days are accounted for. 

An important point to understand is that in this report the data loss is expressed in terms of 

lost observing time. This is straightforward in cases where operations were interrupted or missed. 

However in other cases, it can be more difficult to calculate. To do this a non-observing time 

loss is typically converted into an equivalent lost observing time. As an example a warm receiver 

will greatly reduce the sensitivity of a telescope. The resulting performance will be in some sense 

equivalent to the station having a cold receiver but observing for (typically) only one-third of the 

nominal time. In a similar fashion, poor pointing is converted into an equivalent lost sensitivity. 

Poor playback is expressed as the fraction of total recorded bits lost. 

From the correlator reports, an attempt is made to determine how much observing time was 

lost at each station. This is not always straightforward to do. Sometimes the correlator notes 

do not indicate that a station had a particular problem while the quality code summary will 

indicate a significant loss. Reconstructing which station or stations had problems and why in 

these circumstances does not always yield accurate results. Another problem is that it is hard to 

determine how much RFI affected the data unless one or more channels were removed and that 

eliminated the problem. Similar problems occur for intermittent poor playback. For individual 

station days, the results should probably not be assumed to be accurate at better than the 5% 

level. 

The results here should not viewed as an absolute evaluation for the quality of each station’s 

performance. As mentioned above the results themselves are only approximate. In addition, some 

problems are beyond the control of the station, such as weather and power failures. Instead the 

results should be viewed in aggregate as an overall evaluation of how much of the data the network 

is collecting as a whole. Development of the overall result is organized around individual station 

performance, but the results for individual stations are noisy. 

Since stations typically observe with more than one other station at a time, the lost observing 

time per station is not equal to the overall loss of VLBI data. Under some simplifying assumptions, 

the loss of VLBI data is roughly about twice the loss of observing time. The argument that supports 

this has been described in previous years’ versions of this report. 

18 IVS 2003 Annual Report 
NVI, Inc./GSFC Network Coordinator 

t 

For the 188 sessions with results available from 2003, there are 1040 station days or almost 

G stations per session on average. Of these session days about 14.2% (or about 148 days) of the 

observing time was lost. For comparison, the results for 2002 were about 12.2%, for 2001 about 

11.6%, and for a subset of 1999-2000 the results were about 11.8%. 

The observing time lost for 2003 is somewhat worse than previous yeam which were more 

typically around 12%. If these observing time losses are converted into VLBI data yield losses, 

then 2003 had about 28% VLBI data loss and previous years about 24%. Whether these results 

reflect a significant decline in performauce is not clear. There were several significant problems 

that contributed large data losses to 2003's results. Typically these were receivers that either failed 

or had their cryogenics fail or antenna failures. Without more information about the long term 

performance of the network, these problems might be considered anomalous. 

In previous years an assessment of each station's performance was given in this report. That 

practice has been discontinued. Although many caveats were provided to discourage people from 

assigning too much significance to the results, there was feedback that suggested that the results 

were being over-interpreted. Some stations reported that their funding could be placed in jeopardy 

if their performance appeared bad even if it was for reasons beyond their control. Last and least, 

there seemed to be some interest in attempting to "game" the system to improve the individual 

results. Consequently, this year only su~~~ary results are presented. 

For the purposes of this report, the stations were divided into two categories: (A) those that 

were included in 14 or more network sessions, and (B) those in nine or fewer. Some of the stations 

in the former category had been included in as many as 100 sessions. The distinction between 

these two groups was made on the assumption that the results would be more meaningful for the 

stations participating in more sessions. 

There are 15 stations in the 14 or more session category. Of these 10 successfully collected 

data for approximately 90% of their expected observing time. Four more stations collected 70% 

or more. One station in this group collected about 60%. The vast majority of the commonly used 

stations are in the 90% or more category. 

There are 22 stations in the nine or fewer session category. This category included several 

stations that had previously not been included IVS sessions, including several domestic Japanese 

stations. The range of successful observing time for stations in this category was 35'?46-100%. The 

median success rate was 87%. Overall the stations in this category observed successfully about 

78% of the time. 

Although the results are not being reported for individual stations, a few stations deserve 

special recognition for how much their data collection improved from the previous year. Four 

stations improved the percentage of data they collected by more than 5%- These stations are 

Fortaleza, HartRAO, Ny-Alesund, and Onsala. Given the high level of reliability of these stations 

it will be impossible for most of them to improve by this much again this year. 

The losses were also analyzed by sub-system for each station. Individual stations can contact 

the network coordinator (weh@ivscc.gsfc.nasa.gov) for the break-down for their individual station. 

A summary of the losses for the entire network is presented in Table 1. 

The categories in Table 1 are rather broad and require some explanation. The "Receiver" 

category includes all problems related to the receiver including out-right failure, loss of sensitivity 

because the cryogenics failed, and design problems that impact the sensitivity. The "Antenna" 

category includes all antenna problems including mis-pointing, antenna control computer failures, 

and mechanical break-downs of the antenna. The "Unknown" category is a special category for 

IVS 2003 Annual Report 19 
Network Coordinator NVI, Inc./GSFC 

Sub-system 

Receiver 

Table 1. Data Lost by Sub-system 

Percentage lost 

25.2 

~ 

Shipping 

Miscellaneous 

Rack 

Operat ions 

Clock 

Software 

Total 

Antenna 

Unknown 

Recorder 

6.1 

6.0 

5.0 

3.6 

3.4 

0.1 

100.0 

cases where the correlator did not state or was unable to determine a cause of the loss, but also 

includes the upper X-band IF problem at TIGO which has yet to be understood. The “Recorder” 

category includes all electrical and mechanical problems related to the recorder system (tape or 

disk). This includes passes that are unrecoverable because of overwriting. The “RFI” category 

includes all losses directly attributable to interference. The “Shipping” category includes data 

that could not be correlated because the media was either lost in shipping or held up in customs 

long enough that it could not be correlated with the rest of the session data. The “Miscellaneous” 

category includes several small problems that do not fit into other categories, including errors in 

the observing schedule provided by the Operation Centers. However, by far the largest contributor 

to this category is power failures. In retrospect power failures should have had their own category. 

The “Rack” category includes all failures that could be attributed to the rack (DAS) including the 

formatter and BBCs. The “Operations” category includes all operation errors, such as DRUDG-ing 

the wrong schedule, starting late because of shift problems, problems changing tapes and others. 

The “Clock” category includes situations where correlation was impossible because either the clock 

offset was not provided or was wrong leading to no fringes. It is difficult to be sure in some of 

these cases that the clock offset was the culprit, but in some it was clear. The “Software” category 

includes all instances of software problems causing data to be lost. This includes crashes of the 

Field System, crashes of the local station software, and operating system problems. This category 

could also include errors in files generated by the DRUDG program, but none of these were noted 

for 2003. 

From the results it can be seen that receiver, antenna, and recorder account for more than 50% 

of the losses. In fact for 2003 there were several unusual receiver and antenna problems. If these 

are not repeated in 2004, the data yield should be better. Additionally, the data losses associated 

with the recorder should go down significantly as more stations switch to using disk drives for 

media. The disk systems are much more reliable than tape recorders. 

20 IVS 2003 Annual Report 
NVI, Inc./GSFC Network Coordinator 

2. Clock Offsets 

0.5 

0.0 

-0.5 

-2.0 

-2.5 

-3.0 

1/1/2003 2Ro12ow 411m yJ1m 7mm 018/X)o lDRB12003 12/17/2003 

IMe 

Figure 1. Kokee UTC Correlator Adjustment 

As noted in the previous year’s report, it is important to develop consistent procedures for 

handling the clock offsets during the correlation process. Stations measure the offset between their 

formatter and the UTC time provided by GPS. The correlators typically apply a small, a few 

peconds or less, adjustment to the measured offsets in order to align the data to get fringes. If 

the adjustments are not applied in a consistent fashion by all correlators a corresponding error will 

be made in the UT1-UTC parameter adjustments. This will af€ect the quality of IVS products at 

the level of the inconsistency in the adjustments applied for correlation. This could be corrected 

during the data analysis, but currently no analysis packages do this. It would require a significant 

amount of bookkeeping to add this feature now. 

Last year’s report recommended that the correlators develop a consistent table of adjustments 

to correct the local measurements of the formatter relative to GPS. This would remove a source of 

correlator-to-correlator and session-to-session variability in the UT1-UTC results. It was suggested 

that in developing this table the applied correction for Kokee should be artificially set to zero. 

IVS 2003 Annual Report 21 
Network Coordinator NVI, Inc./GSFC 

Although not strictly correct, it is a simple approach and will maintain a level of consistency with 

old data, much of which was processed by WACO with an offset of zero for Kokee. However, the 

“true” adjustment will have to be compensated for when an effort is made to align the ICRF and 

ITRF at this level. It was also recommended in last year’s report that a reference for the clock 

rate should be established at the same time. Although this is not as critical as the offset, it can 

easily be handled at the same time. Of course a good candidate station for the clock rate reference 

has to be found. As of last year’s report, it seemed that Kokee’s small rate relative to GPS, le-14 

or better, would make it a good candidate. This would be a convenient choice for consistency’s 

sake since again WACO has assumed that Kokee had a zero rate for much of the old data. This 

discussion is carried on in more detail in last year’s report. 

At the IVS Directing Board meeting in September 2004, the Correlator Representative to 

the Directing Board had offered to develop a consistent set of adjustments for the correlators 

to use. Currently this set of adjustments is under development [K. Kingham, USNO, private 

communication]. Consequently it would be premature to expect the offsets to be consistent for 

2003. As a sample of the situation in 2003, the adjustments for Kokee are shown by correlator 

in Figure 1. In this figure it can be seen that the UTC adjustment applied by WACO is zero. 

Both Bonn and Haystack variable but small non-zero adjustments. The results for UT1-UTC will 

be affected at the level that the adjustments vary, less than 0.5 psecond. However the offsets 

applied by Penticton have considerably more variation. Since there were no sessions involving 

Kokee processed by the GSI correlator, we have no information about the adjustments for this 

station and correlator combination. 

It is not only important that the UTC adjustments applied by the correlators are all consistent, 

but also the final clock value must be applied in the generation of the time-tags for the observations. 

It is known that this is done at the three Haystack Observatory developed correlators: Bonn, 

Haystack, and WACO. However it is not known what the Penticton and GSI correlators do in this 

regard. Requests have been made to B. Petrachenko and K. Takashima, respectively, to find out 

more about how these correlators handle the offsets. (We also have no information about clock 

offsets are handled by the Miytaka correlator. However, the IVS geodetic sessions that Miytaka 

processes are not primarily intended to measure UT1-UTC.) If the final clock value is not applied 

in the generation of the time tags, the session-tesession variation in the locally measured formatter 

to GPS will be included in the UT1-UTC parameter estimates. 

Another area of concern is that different recording systems may require different adjustments. 

A particular example is that the CRF22 session was correlated at WACO using data from two 

different systems: K3 formatter recorded to tape and a K5 recorder using disks. WACO found a 

3.3 psecond clock offset between the two systems. This difference corresponds to almost a kilometer 

of cable difference. This does not seem realistic. If no cause for this is found, and probably even 

if it is, it will be necessary to calibrate the differences between different systems. This might be 

undertaken by recording the same data with two or more systems and then comparing the final 

clock offsets that are needed to correlate them. 

~ ~ 

22 IVS 2003 Annual Report 
MIT Hawtack Obsewatorv IVS Technolorrv Coordinator 

IVS Technology Coordinator Report 

Abstract 

The efforts of the Technology Coordinator in 2003 were primarily in the following areas: 1) creation 

of IVS Working Group 3 far VLBI2010, 2) continued development of the VSI-E specification for eVLBI, 3) support of the 2nd annual e-VLBI Workshop held at JIVE. We will describe each of these 

briefly. 

1. IVS Working Group 3 - VLBI2010 

At the September 2003 IVS Directing Board meeting, the IVS Working Group 3 was formally 

created. The VLBI2010 Working Group will examine current and future requirements for VLBI 

geodetic systems, including all components from antennas to analysis, and produce a report with 

recommendations for a new generation of systems that meet the following criteria: 

0 Highest-precision geodetic and astrometric results 

0 Low cost of construction 

0 Low cost of operation 

0 Fast turnaround of final results 

Among the issues to be explored are: 

0 Modernization of VLBI data-acquisition systems for higher stability and reliability, wider 

0 Small, low-cost, fast-moving antennas 

0 New observing strategies 

0 Optimum and practical observing frequencies 

0 Fully automated observations; remote monitoring 

0 Transmission of data via high-speed network (e-VLBI) 

0 Possible correlator upgrades 

0 Fast turnaround of results by full pipelining of data from antennas to correlator to final 

bandwidth, lower cost 

analysis 

Among the factors encouraging the VLBI2010 initiative: 

0 Continuing RFI problems at many sites 

0 DSN moving to X/Ka (32 GHz) band observations. Advantage: eliminates S-band RFI 

0 Aging antennas 

0 Technology advances in disks and e-VLBI 

0 Concerns in the US: 

- 

IVS 2003 Annual Report 23 
IVS Technology Coordinator MIT Haystack Observatory 

- Retirement of current practitioners 

- Reduced support for VLBI technology development by sponsoring agencies 

Goals of VLBI2010: 

0 Unattended observing 

0 Global coverage 

0 Electronic data transfer, near real-time correlation. 

0 Smaller antennas? (~12m- for expected to be available for -$150k) 

0 Spanned bandwidth 4 GHz 

We will draw on the resources of both the astronomy and geodesy VLBI communities in these 

The VLBI2010 Working Group is composed of 16 members drawn broadly from the geodetic 

investigations, as well as other relevant expertise (such as SKA and ATA, for example). 

VLBI community: 

0 Brian Corey - antennas, RF/IF systems, calibration 

0 Hayo Hase - antenna systems 

0 Ed Himwich- control, data management 

0 Hans Hinteregger - digital backend systems, correlators 

0 Tetsuro Kondo - data systems, data transport, real-time 

0 Yasuhiro Koyama - data systems, data transport 

0 Chopo Ma - post-correlation analysis; data management 

0 Zinovy Malkin - post-correlation analysis 

0 Arthur Niell - atmospheric calibration, analysis 

0 Bill Petrachenko - antenna arrays, multi-beam VLBI, frequency standards 

0 Wolfgang Schlueter - antennas, observing strategies, frequency standards 

0 Harald Schuh - post-correlation analysis, cross-technique use 

0 Dave Shaffer - observing strategies, systems, analysis 

0 Gin0 Tuccari - digital backend systems 

0 Nancy Vandenberg - scheduling, observing strategies 

0 Alan Whitney - data systems, data transport, correlators 

The Working Group is co-chaired by Alan Whitney and Arthur Niell. A draft report is expected 

to be available in spring 2004, with a final report approximately 3 months later. 

24 IVS 2003 Annual Report 
MIT Haystack Obsavatory IVS Technology Coordinator 

2. VLBI Standard Interface - e-VLBI (VSI-E) 

Work continues on the development of the VSI-E specification for a standardized data format 

for e-VLBI interchange. At the 2003 e-VLBI Workshop in JIVE, many of the members of the 

VSI-E committee met to discuss the choice of an underlying protocol for VSI-E. There was general 

consensus that the well-known and well-developed Internet Real-Time Protocol (RTP) would best 

serve as a base for the development of VSI-E. RTP has the following advantages: 

e Developed for real-time transmission of digitally-sampled analog data 

e Well developed, supported, and widely used 

e Built-in monitoring and network and end-system performance 

e Adaption to varying network capability and performance 

e Built-in multi-cast and multi-streaming support 

On the other hand, RTP, as currently defined, is not entirely suitable for the wide range of eVLBI operational conditions, ranging from disk-buffered at both station and correlator to full 

real-time operation. Much effort has been expended to extend the current RTP protocol to handle 

the full range of operational space that e-VLBI demands. Furthermore, these extensions are 

being developed as generally as possible so that the extended RTP standard that encompasses 

e-VLBI will have a good chance of being accepted as an Internet standard protocol by the Internet 

Engineering Task Force. Acceptance by the IETF would lend worldwide credibility to the extended 

RTP standard and help encourage its use and support. To this end, the draft VSI-E standard is 

being subjected to minute scrutiny by non-VLBI network experts as well as VLBI network experts. 

We expect a final draft for ratification to be ready in early/mid 2004. 

The members of the VSI-E committee are: 

e 

a 

e 

e 

e 

e 

e 

a 

e 

a 

e 

e 

e 

a 

e 

Wayne Cannon; York University, Canada 

Brent Carlson; DRAO, Canada 

Dick Ferris; ATNF, Australia 

Dave Graham; MPI, Germany 

Ed Himwich; NASA/GSFC, US. 

Richard Hughes-Jones; Manchester Univ, England 

Nori Kawaguchi; NAO, Japan 

Tetsuro Kondo; ClU, Japan 

David Lapsley; Haystack, U.S. 

Sergey Likhachev; ASC, Russia 

Ari Mujunen; Metsahovi, Finland 

Sergei Pogrebenko; JIVE, Netherlands 

Jon Romney; NRAO, U.S. 

Ralph Spencer; Jodrell, England 

Harro Verhouter; JIVE, Netherlands 

Alan Whitney; Haystack, U.S. 

IVS 2003 Annual Report 25 
IVS Technology Coordinator MIT Haystack Observatory 

3. Second International e-VLBI Workshop Held at JIVE 

Approximately 80 attendees representing 15 institutions worldwide participated in a 2-day 

workshop held at JIVE on 15-16 May 2003. The purpose of this workshop was to continue the 

work of the 2002 e-VLBI workshop at Haystack Observatory to explor the current state of highspeed VLBI data transmission. Among the topics discussed were: 

0 Reports on e-VLBI tests and demonstrations 

0 Plans for ongoing e-VLBI development 

0 Status of interaction with network providers and developers 

0 International networking facilities - now and future 

0 Standards and protocols for e-VLBI data transfer. 

0 Hardware and software interfaces to telescope back-ends and correlators 

Progress in e-VLBI continues to be rapid, particularly with the rapid spread of global highspeed networks, the adoption of e-VLBI compatible data systems (Mark 5, K5, PC-EVN), and 

the rapid drop in prices for high-speed network equipment. Over the last year, international eVLBI demonstrations have reached as much as 700 Mbps (Japan to U.S.). In addition to e-VLBI 

data transmission, we heard about the development of new software correlators in Japan and 

Europe, as well as plans for continued e-VLBI development in several countries. The program 

committee consisted of Yasuhiro Koyama of CRL, Steve Parsley of JIVE, Jon Romney of NRAO 

and Alan Whitney of Haystack Observatory. Presentations from the workshop are available on-line 

at http://www.jive. nl/evlbi-ws/meeting. 

26 IVS 2003 Annual Report 

Geodetic Survey Division, Geomatics Canada. Natural Resources Canada Algonquin Radio Obsenatory 

Algonquin Radio Observatory 

Mario B&u b6, Calvin Klatt, -4nthony Searle 

Abstract 

The Algonquin Radio Observatory (ARO) is situated in Algonquin provincial park, about 250 km 

north of Ottawa and is operated by the Geodetic Survey Division (GSD) of Natural Resources Canada 

in partnership with the Space Geodynamics Laboratoq> CRESTech. 

The antenna is involved in a large number of international geodetic VLBI sessions each year and 

is a key site in the ongoing Canadian S2 developments. The ARO is the most sensitiw WS Network 

St at ion. 

This report summarizes recent activities at the Algonquin Radio Observatory. 

Figure 1. Algonquin Radio Obsenatorp 46m Antenna 

1. Overview 

The ARO 46 m antenna was used in the first successful VLBI experiment in 1967 and was 

involved as early as 1968 in geodesy, when the baseline length between the ARO and a telescope 

in Prince Albert, Saskatchewan was measured to be 2143 km (sigma=20m). 

~ 

IVS 2003 Annual Report 29 
Algonquin Radio Observatory Geodetic Survey Division, Geomatics Canada, Natural Resources Canada 

The GSD also maintains a permanent GPS monitoring station at Algonquin which is used 

by all IGS Analysis Centers as a fiducial reference. Satellite laser ranging and absolute gravity 

observations are also available for the site which is located on the stable Precambrian Canadian 

Shield. Local site stability has been monitored regularly using a high-precision network. 

2. Site Improvements 

In order to improve the operational performance of Algonquin, GSD undertook a major upgrade 

of the antenna control system which was completed in 1997. 

This antenna control system still uses the original azimuth and elevation encoders to determine 

antenna position. We have made some progress in the effort to upgrade these and efforts continue 

in a manner that will not affect scheduled operations. 

Figure 2. Visiting neighbour 

3. General Specifications 

0 Latitude : N 45” 57’ 19.812” 

0 Longitude : E 281” 55’ 37.055” 

0 Elevation : 260.42m 

0 Reflector : 46m diameter with first 36.6m made of 0.634cm steel plates surrounded by 4.6m 

of steel mesh. 

0 Foci : S and X band at prime focus. Gregorian capability with 3m elliptical subreflector. 

0 Focal length : 18.3m (prime focus) 

0 Focal ratio : f/D = 0.4 for full surface and 0.5 for solid surface. 

30 IVS 2003 Annual Report 
Geodetic Survey Division, Geomatics Canada, Natural Resources Canada Ngonquin Radio Observatory 

0 Surface accuracy : 0.32cm for solid portion and 0.64 for mesh. 

0 Beamwidth : 3.0 arcmin at 3cm wavelength (10Ghz) 

0 Azimuth speed : 24 degrees per minutes. 

0 Elevation speed : 5 degrees per minutes. 

0 Receiver : S and X cryogenic receiver. 

0 VLBI equipment : VLBA4 with thin tape drive. S2 DAS and RT. 

0 PCFS version : 9.5.3 

0 Time standard : NR Maser 

0 GPS receiver : Bencwark 

0 Timing receiver : CNS clock 

4. Antenna Survey 

The antenna is surrounded by a high stability network made of thirteen concrete piers. This 

network has been precisely measured five times to obtain the geodetic tie between the VLBI, the 

GPS, and the SLR reference points with a precision of a few mm. The VLBI antenna itself requires 

a special indirect survey since the reference point cannot be accessed directly. 

5. Algonquin Operations 

Algonquin Radio Observatory is involved in several international VLBI networks. Geodetic 

VLBI activities are summarized below. 

ARO participated in the VLBI observation of Nozomi for precise orbit determination in collaboration with the Institute of Space and Astronomical Science (ISAS), Communication Research 

Laboratory (ClU) Japan, the Canadian Space Agency (CSA) and SGL, CRESTech. 

ARO has participated in testing of bistatic radar observations of satellites in collaboration 

with SGL. 

5.1. Sessions Performed January 1, 2003 - December 31, 2003 

Session Type Number of Sessions 

R4 50 

E3 10 

R&D 10 

T2 2 

Total 72 

IVS 2003 Annual Repd 31 
Fortaleza Centro de Fkidio Astronomia e Aplicacijes Espaciais, CRAAE (Mackenzie, INPE, USP, UNICAMP) 

Fortaleza Station Report for 2003 

Pierre Kaufmann, A. Macilio Pereira de Lucena, Claudio E. Tateyama 

Abstract 

This is a brief report on the activities carried on at Fortaleza geodetic VLBI Station (ROEN: 

RAdio Observat6rio Espacial do Nordeste), EusBbio, CE, Brazil, in 2003, consisting mainly of 66 VLBI 

observing sessions and continuous GPS monitoring recordings. 

1. Introduction 

The Rddio Observat6rio Espacial do Nordeste, ROEN, located at INPE facilities in Eusebio, 

nearly 30 km east from Fortaleza, Ceard State, Brazil, began operations in 1993. Geodetic VLBI 

and GPS observations are carried out regularly, as contributions to international programs and 

networks. ROEN is part of the Brazilian space geodesy program which was carried out by CRAAE, 

the Center for Radio Astronomy and Space Applications (a consortium between Brazilian institutions Mackenzie, INPE, USP and UNICAMP). During the year of 2003 the operational staff 

and part of infrastructure were maintained within an agreement between the Instituto Nacional 

de Pesquisas Espaciais, INPE and Instituto Presbiteriano Mackenzie through its Universidade 

Presbiteriana Mackenzie, Centro de Rgdio-Astronomia e Astrofkica Mackenzie, CRAAM. Part of 

operation costs and technical maintenance, support of infrastructure, are sponsored by US agencies NASA, USNO and NOAA, with Agreements with Mackenzies CRAAM, under the Brazilian 

Program for Space Geodesy. 

Figure 1. Fortaleza staff in front of antenna 

2. Brief Description of ROEN Facilities 

The largest instrument of ROEN is the 14.2 m radio telescope, on one alt-azimuth positioner. 

It is operated at S- and X-bands, using cryogenic radiometers. The system is controlled by Field 

32 IVS 2003 Annual Report 
Centro de Mi0 Astronomia e Aplica@es %paciais, CRAAE (Mackenzie, INPE, USP, UNICAMP) Fortaleza 

System, Version 9.6.2 program. Observations are recorded with a Mark I11 data acquisition system. 

One Sigma-Tau hydrogen maser clock standard is operated at ROEN. 

GPS monitoring is performed by one dual frequency GPS Rogue receiver operated continuously. 

The collected data are provided to the IGS center, as well to Brazilian IBGE center. ROEN has 

all basic infrastructure for mechanical, electrical and electronic maintenance of the facilities. 

3. Space Geodesy Team 

The Brazilian space geodesy program is coordinated by Prof. Pierre Kaufmann, from Sib Paulo 

main office at CRAAM( CRAAE) /Institute and Universidade Presbiteriana Mackenzie, receiving 

scientific assistance from Dr. Claudio E. Tateyama, and partial administrative support from 

Valdomiro S. Pereira and Neide Gea. Partial technical assistance is given by Itapetinga Radio 

Observatory st&, near Siio Paulo, also operated by INPE/Mackenzie. 

The Fortaleza Station facilities and geodetic VLBI and GPS operations are managed in site 

by Eng. Adeildo Sombra da Silva 

(CRAAE/Mackenzie), and technician Avicena Filho (CRAAE/INPE). Local administrative sup 

port was given by Dadimar Dias Nobre. 

A. M. P. de Lucena (CRAAE/INPE), assisted by Eng. 

4. Geodetic VLBI Observation 

Fortaleza participated in following geodetic VLBI experiments, as detailed in the table below 

for the year 2003. 

Experiment Number of Sessions 

IVSR4 50 

IVST2 07 

1VSCR.F 03 

IVSOHIG 06 

5. Development and Maintenance Activities in 2003 

Considerable attention was given to technical maintenance problems, specially to the following 

ones: 

1. 

2. 

3. 

4. 

5. 

Tests and electrical alignment of the DC motors in both axis. 

Updating and tests for new versions of Field System. 

Repair on cryogenic system with replacement of cold head. 

Repairs on the following circuits, modules, or systems: Mark I11 video converters, Mark I11 

power supplies and Mark I11 IF3 module. 

Maintenance of web site (http://www.roen.inpe.br). 

6. GPS Operation 

The IGS network GPS receiver operated regularly at all times during 2003. Data were collected 

and uploaded to IGS/NOAA computer. 

IVS 2003 Annual Report 33 
Fort aleza Centro de Udio Astronomia e Aplicaq6es Espaciais, CRAAE (Mackenzie, INPE, USP, UNICAMP) 

7. Students Activities 

The following students have participated in the program during 2003: 

1. Carlos Fabian0 Barros Moreira( CEFET/CE), ROEN; 

2. Jose Ronnylson Santos dos Anjos(CEFET/CE), ROEN; 

3. Danilo Morales Teixeira(FBCEE/UPM), CRAAM-SP. 

8. Scientific Paper 

TATEYAMA, C.E.; KINGHAM, K.A.; "Structure of OJ 287 from Geodetic VLBA Data", in 

press, Astrophys.J., 2003. 

9. Visitors 

In 2003 we received at ROEN the visits fiom Mr. William T. Wildes, the program manager at 

GSFC/NASA and Mr. Charles Kodak, from Honeywell, for technical inspections and discussions. 

10. ROEN Participation in TOW 

Engineer Adeildo Sombra da Silva, from ROEN, has participated in the IVS Technical Operations Workshop (TOW), held by IVS, at Haystack Observatory, MIT, Massachusets, USA, 

September 21-25 2003. 

11. Future Plans 

The Mark IV formatter was purchased and received in 2003. It is planned to complete the 

Mark I11 updating during 2004. 

34 IVS 2003 Annual Report 
NASA Goddard Space Flight Center Gilmore Creek Geophysical Observatory 

Gilmore Creek Geophysical Observatory 

Kyle Eherhart 

Abstract 

The following report provides a general technical description and operational overview of the Gilmore 

Creek Geophysical Observatory located near Fairbanks, Alaska. 

Figure 1. Gilmore Creek Geophysical Obser\atory’s telescope and building, Fairbanks, Alaska. 

1. GCGO at Fairbanks 

Gilmore Creek Geophysical Observatory (GCGO) is located 22 km northeast of Fairbanks, Alaska. 

The observatory is co-located with the NOAA weather satellite command and data acquisition 

station. The station sits on an 8,500 acre reservation that is mostly undeveloped wilderness. Ten 

antennas are in operation. GCGO was instrumented by NASA’s Crustal Dynamics Project in the 

mid 80’s for the Alaskan mobile VLBI campaign and used as the base station for those geodetic 

measurements. The GCGO is part of the NASA Space Geodesy program in cooperation with the 

US. Naval Observatory. 

11% 2003 Annual Report 35 
Gilmore Creek Geophysical Observatory NASA Goddard Space Flight Center 

2. Technical Parameters of GCGO 

The 26 meter telescope, monument number 4047, X-East Y-North, latitude N 64” 58’ 43.81288” 

and longitude E 147” 29’ 42.18552” height 306.418 meters is hydraulic-operated and controlled 

by a Modcomp computer system (see table 2). The DAT rack is a VLBA terminal and recorder 

(thin tape). The X/S band microwave receiver has a cryogenic low noise front end. VLBI Field 

System version 9.5.7 is used with a PC. Hydrogen Maser NR 5 is the time standard with an HP 

Cesium for the telescope computer. A CNS (TAC) receiver is monitored by the TAC32 software 

for GPS offset measurements. The JPL GPS scintillation project is observed using an Ashtech and 

8100 Rogue GPS receiver.The Institut Geographique National in France operates a DORIS beacon 

located near the NOAA VHF transmitter building. Nortel Data Network Systems operates the 

PRARE (Precise Range and Range Rate Equipment) for the German Space Agency. CLS from 

France operates the ARGOS and ARGOS-NEXT beacon. The ARGOS-NEXT platform is located 

next to the NOAA 26 meter antenna. 

Table 1. Address of GCGO near Fairbanks. 

NOAA/NESDIS FCDAS 

1300 Eisele Road 

Fairbanks, AK 99712 

Table 2. Technical parameters of the GCGO radio telescope for geodetic VLBI. 

Parameter GCGO 

owner and operating agency NOAAINASA 

year of construction 1962 

receiving feed primary focus 

diameter of main reflector 

focal length 10.9728 meters 

surface accuracy of reflector 

X Y mount 

26 meters 

889 mm rms 

1 degree per second 

S-band 2.2 - 2.4,GHz 

Tsys 62 K 

SEFD (CASA) 650 Jy I,. G/T 35.3 dBIK 

X-band 8.1 - 8.9, GHz 

SEFD (CASA) 550 Jy 

G/T 44.5 dB/K 

36 IVS 2003 Annual Report 
- NAS. Goddard Space Flight Center Gilmore Creek Geophysical Observatory 

3. Staff of the Gilmore Creek Facility, Fairbanks, Alaska 

GCGO is co-located with the NOAA Fairbanks command and data acquisition facility. The NOAA 

Manager is Lance Seman. The site is operated by Space Mark International with Janine Jmis 

as Project Manager and Roger Kermes as the Operations Manager. S. Caskey and K. Eberhart 

are assigned as GCGO technical staff with T. Knuutila, Z. Padilla, and others assisting. The 

telescope’s hydraulic system is maintained by M. Meindl, A. Sanders and F. Holan. Day by day 

scheduling is done by “VI, Cindy Thomas and VLBI technical directives/contract modifications 

by NASA/GSFC, Bill Wildes. 

4. Status of Gilmore Creek Geophysical Observatory 

In 2003 GCGO was scheduled with 105 sessions and missed three. In early 2003 GCGO observed 

several sessions warm due to problems with our helium lines. We also replaced our recorder’s 

capstan motor in April, the Dewar in June, a servo valve on our antenna in September and the 

head in our recoder in October. Our visitors included Senator Ted Stevens, NASA Administrator 

Sean O’Keefe, Bill Wildes GSFC/NASA, and Ed Himwich/NVI. 

5. Outlook 

A Mark 5 installation and Mark 4 formatter are expected early in 2004. 

c 

IVS 2003 Annual Report 37 
Goddard Geophysical and Astronomical Observatory NASA Goddard Space Flight Center 

Goddard Geophysical and Astronomical Observatory 

Jay Redmond, Charles Kodak 

Abstract 

This report summarizes the technical parameters and the technical staff of the VLBI system at the 

fundamental station GGAO. It also gives an overview about the VLBI activities during the previous 

year. The outlook lists the outstanding tasks to improve the performance of GGAO. 

1. GGAO at Goddard 

The Goddard Geophysical and Astronomical Observatory consists of a radio telescope for VLBI, 

SLR site to include MOBLAS-7, SLR-2000 (development system), a 48” telescope for developmental two color Satellite Ranging, a GPS timing and development lab, meteorological sensors and a 

H-maser. In addition, we are a fiducial IGS site with several IGS / IGSX receivers. 

Figure 1. Old semi permanent MV-3 VLBI 

antenna. 

Figure 2. New permanent MV-3 antenna. 

GGAO is located on the east coast of the United States in Maryland. It is about 15 miles NNE 

of Washington D.C. in Greenbelt, Maryland (Table 1). 

2. Technical Parameters of the VLBI Antenna at GGAO 

The radio telescope for VLBI at GGAO (MV3) was originally built as a mobile or transportable 

station. It was previously known as Orion and was part of the original CDP. It is now being used as 

a fixed site having been moved to Goddard and semi-permanently installed here since the spring 

of 1991 as shown in figure 1. In the winter of 2002 the antenna was taken off its trailer and 

permanently installed at GGAO as shown in figure 2. The design criteria were 

transportability on two tractor trailers utilizing a 5 meter dish size to maximize receive and 

mobility considerations, 

setup of the radio telescope within eight hours (although it has been used as a fixed site since 

the spring of 1991) 

38 IVS 2003 Annual Report 
Goddard Geophysical and Astronomical Observatory __ NASA Goddard Space Flight Center 

Parameter 

owner and operating agency 

year of construction 

Table 1. Location and addresses of GGAO at Goddard. 

Longitude 76.4935' W 

Latitude 39.0118' N 

Code 299.0 

Goddard Space Flight Center, (GSFC) 

Greenbelt, Maryland 20771 

GGAO-VLBI 

NASA 

1982 

The technical parameters of the radio telescope are summarized in Table 2. 

Table 2. Technical parameters of the radio telescope of GGAO for geodetic VLBI. 

Tsvs 

Bandwidth 

24K 

800MH2, -2dB 

diameter of main reflector d 

azimuth range 

azimuth velocity 

azimuth acceleration 

elevation range 

elevation velocity 

elevation acceleration 

5m 

0...540' 

3'1s 

1'12 

0...90" 

3'1s 

1" Is2 I 

X-band I 8.18 ~ ~ - 8.98 - __ GHz - 

receiving f eed I Cassegrainfms 

recording media 

Field System version 

thin-tape only 1 9.6.9 (9.5 BETA) 

3. Technical Staff of the VLBI Facility at GGAO 

The GGAO VLBI facility gains from the experiences of the staff from the Research and Development VLBI support staff. GGAO is a NASA R&D and data collection facility, operated under 

IVS 2003 Annual Report 39 
Goddard Geophysical and Astronomical Observatory NASA Goddard Space Flight Center 

Name Background 

Jay Redmond engineering technician 

TBD engineerinR technician 

contract by Honeywell Technology Solutions Incorporated (HTSI). Table 3 lists the GGAO station 

staff that are involved in VLBI operations. 

Dedication Agency 

100% HTSI 

20% HTSI 

Date 

2003-03- 18 

2003-03-12 

2003-04-08 

2003-05-07 

2003-06-18 

2003-07-09 

2003-09-1 6 

2003-10-14 

4. Status of MV3 at GGAO 

Experiment 

T2015 

RDV37 

T2016 

RDV38 

RDV39 

RDV40 

T2021 

T2022 

GGAO participated in several VLBI experiments which are listed in table 4. In addition to the 

scheduled experiments listed in table 4, MV3 has participated in several unscheduled experiments 

for VLBI developmental purposes and various other developmental activities. 

Table 4. Participation of GGAO in VLBI Experiments from March 12, 2003 to October 10, 2003. 

5. Outlook 

GGAO will continue to support both scheduled experiments and developmental activities. The 

1. Continue testing of pre-release versions of PC-FS and new Linux kernel releases. 

2. Continue with research on Mark 5 hardware development. 

3. Continually striving to improve the performance of the entire MK4 data collection and station 

4. MV-3 has installed the Mark 5 and e-VLBI hardware and has begun testing real-time from 

Correlation with the Westford data on the Mark 4 correlator was 

5. The MV-3 antenna at GGAO has been permanently fix to the ground and has been resurplan for 2004 consists of: 

specific equipment. 

GGAO to Haystack. 

successful. (Oct 24, 2002). 

veyed. (Oct. 2003) 

40 IVS 2003 Annual Report 
HartRAO. hW Hartebeesthoek Radio Astronomy Observatory (HartRAO) 

Hartebeest hoek Radio Astronomy Observatory (Hart RAO) 

Ludwig Combrinck 

Abstract 

HartRAO is the only fiducial geodetic site in Africa and participates in VLBI, GPS and SLR global 

networks. This report provides an overview of our geodetic VLBI activities during 2003. The status 

of the 26m radio telescope surface upgrade is reported. F’uture plans include automating the dichroic 

system which allows duel frequency operation. In order to meet future requirements of geodetic VLBI. 

we have initiated the first steps towards founding a new space geodetic station which will cater to 

new developments and challenges as addressed by VLBI2010 and future requirements of GPS and 

SLR/LLR. 

Figure 1. The last panel of the 26 metre radio t,eiescope surface upgrade being installed by Simon Norake 

and Andrew Blasiteng. 

1. Geodetic VLBI at HartRAO 

HartRAO is located north of Krugersdorp (close to Johannesburg), South Africa, in a valley 

of the foothills of the Witwaters mountain range. HartRAO uses a 26 metre equatorially mounted 

Cassegrain radio telescope built by Blaw Knox in 1961. The telescope was part of the NASA 

deep space tracking network (Deep Space Instrumentation Facility (DSIF) 51) until 1975 when 

the facility was converted to an astronomical observatory. The telescope is colocated with an SLR 

station (MOBLAS-6) and an IGS GPS station (HRAO). HartRAO joined the EVN as an associate 

member during 2001. Astronomical and geodetic VLBI have been allocated equal shares (15% 

each) of telescope time. 

2. Technical Parameters of the VLBI Telescope of HartRAO 

The feed horns used for 13 cm and 3.5 cm are single polarised conical feeds. Both S and X 

bands have right hand circular polarisation. The RF amplifiers are cryogenically cooled HEMTS. 

I\:S 2003 Annual Report 41 
Hartebeesthoek Radio Astronomy Observatory (HartRAO) HartRAO, NRF 

Table 1 contains the technical parameters of the HartRAO radio telescope [l]. Upgrade to a Mark 

5 recording unit has taken place during late 2003 and has been installed successfully. 

Table 1. Technical parameters of the radio telescope of HartRAO for geodetic VLBI, [l]. 

~~ 

Parameter 

owner and operating agency 

year of construction 

radio telescope mount 

receiving feed 

diameter of main reflector d 

focal length f 

surface contour of reflector 

f id 

wavelength limit 

pointing resolution 

pointing repeatability 

(standard v = 8.580GHz, A = 0.0349m) 

Tsys 

SSEFD 

Point source 

3 dB beamwidth 

X-band 

S-band 

(standard v = 2.280GHz, X = 0.1316) 

Tsys 

SSEFD 

Point source 

3 dB beamwidth 

VLBI terminal type 

recording media 

Field System version 

attended VLBI observations 

Hart RAO-VLBI 

HartRAO 

1961 

offset equatorial 

Cassegrain 

25.914m 

10.886m 

0.424 

f2.0mm 

2.5 cm 

0.001" 

0.004" 

8.180 - 8.980 GHz 

65 K 

1500 Jy 

17.1 JyIK 

0.092' 

2.210 - 2.344GH~ 

40 K 

1500 Jy 

9.7 JylK 

0.332' 

MKIV 

thin-tape only 

9.4.18 

24h, mode C 

3. Staff Members Involved in VLBI 

Table 2 lists the HartRAO station staff who are involved in geodetic VLBI. Marisa Nickola has 

been responsible for downloading of schedules, preparing SNAP files and related documentation. 

Several of the SLR operators have participated in geodetic VLBI shifts. Jonathan Quick (VLBI 

friend) has continued to provide technical support for the Field System as well as for hardware 

problems. 

42 IVS 2003 Annual Report 
HartRAO, haF Hartebeesthoek Ftadio Astronomy Observatory (HartRAO) 

Name 

Ludwig Combrinck 

Jonathan Quick 

Marisa Nickola 

William Moralo 

Pieter Stronkhorst 

Attie Combrink 

Background Dedication Fhction Programme 

Geodesy 10% Programme Leader Geodesy 

Astronomy 5% Hardware / Software Astronomy 

Technical 50% Logistics/Operations Geodesy 

Technical 5% Operator Geodesy 

Technical 5% Operator Geodesy 

Geodesy 5% Operator Geodesy 

4. Current Status 

During 2003 HartRAO participated in 58 (63 the previous year) experiments (Table 3), which 

utilised the telescope time allocated to geodetic VLBI to its fullest extent. The antenna surface 

upgrade is continuing and the last panel was installed at the end of 2003 (see Figure 1) and 

(Figure 2). It is planned to use holography to determine the overall shape of the dish during 2004. 

Based on the results of the holography, individual panels will be adjusted to obtain the best overall 

surface shape. Automation of the dichroic, which will include the construction of a new and more 

efficient dichroic, will commence once the surface upgrade has been completed. 

Figure 2. The final panel has been installed and we are all milling around in confusion or relief. 

5. Future Plans 

During 2003 we acquired a Mark 5 upgrade. Several parallel experiments using tapes and Mark 

5 have been completed with no technical problems and we will phase out the tapes as soon as it is 

appropriate. 

We have started initial steps towards the development of a new integrated Space Geodesy 

Facility which will support SLR, LLR, VLBI and GPS as well as host a multitude of earth science 

instrumentation. This will mean the construction of a new site, development and implementation 

of new state of the art equipment and will place the southern hemisphere and especially Africa 

IVS 2003 Annual Report 43 
Hartebeesthoek Radio Astronornv Observatorv (HartRAO) HartRAO. NRF 

Table 3. Geodetic VLBI experiments HartRAO participated in during 2002. 

Experiment Number of Sessions 

SUR 3 

CRF 5 

OHIG 6 

R1 35 

SYOWA 4 

T2 5 

Total 58 

securely in the space geodesy arena for the next several decades. We would like to invite possible 

participants in this venture to contact us. 

The Geodesy Programme is an integrated programme, supporting VLBI, SLR and GPS and is 

active in several colloborative projects with GSFC, JPL, GFZ (Potsdam) and local institutes. 

References 

[l] Combrinck, L., Hartebeesthoek Radio Astronomy Observatory (HartRAO), In: International VLBI 

Service for Geodesy and Astrometry 2000 Annual Report, NASA/TP-2001-209979, N. R. Vandenberg 

and K. D. Baver (eds.), 84-87, 2001. 

44 IVS 2003 Annual Report 
University of Tasmania, Geoscience Australia Hobart, Mt. Pleasant Radio Astronomy Observatory 

Hobart, Mt. Pleasant, Station Report for 2003 

Brett Reid, Simon Ellingsen 

Abstract 

This is a brief report on the activities carried out at the Mt. Pleasant Radio Astronomy Observatory 

at Hobart, Tasmania During 2003 the Observatory participated in 38 geodetic VLBI observing sessions. 

The recording system was upgraded from Mark 111 to Mark 5. 

1. Introduction 

The Mt. Pleasant Observatory is located about 15 km north east of Hobart at longitude 147.5 

degrees East and latitude 43 degrees South. The station is operated by the School of Mathematics 

and Physics at the University of Tasmania with financial support kom the University and with 

the aid of an Australian Research Council (ARC) Linkage grant in conjunction with Geoscience 

Australia. The station has participated in geodetic VLBI programs since 1988 but only joined 

IVS in 2002 when we were able to secure funding support for geodetic observations for a five year 

period. The station has a co-located GPS receiver and a site which has been used again during 

2003 for absolute gravity measurements. 

2. Brief Description of VLBI Facilities 

The antenna is a 26m prime focus instrument with an X-Y mount. The focus cabin has recently 

been upgraded to include a feed translator with provision for four different receiver packages which 

enables rapid change over between geodetic and astronomical requirements. An upgrade completed 

during 2003 allows standard receiver packages to provide for operation at L band, S, C, X and K 

bands as well as the dual kequency S/X geodetic receiver. All of these receivers are cryogenically 

cooled. The antenna has a maximum slew rate of 4.0 degrees per minute about each axis. The 

station is now equipped with a Mark 4 electronics rack and a Mark 5 VLBI recording system as 

well as S2 recorder. 

3. StafF 

Staff at the observatory consisted of two academics, Professor Peter McCulloch and Dr. Simon 

Ellingsen as well as the Observatory Manager, Mr. Brett Reid, funded by the University. In 

addition we have an electronics technical officer, Mr. Eric Baynes funded through the ARC grant 

and a half time mechanical technical officer, hh Bany Wilson. For operation of the observatory 

during geodetic observations we rely heavily on support from astronomy post-graduate students. 

At Peter McCulloch’s retirement dinner, Peter was awarded the honour of Professor Emeritus 

by the University of Tasmania in recognition of his contributions in the field of radio astronomy. 

4. Geodetic VLBI Observations 

Hobart participated in 38 geodetic VLBI experiments during 2003. These were divided between 

the R1, OHIG, SYOWA, CRF, SUR, and APSG programs. With the upgrade to Mark 5 during 

IVS 2003 Annual Report 45 
Hobart, Mt. Pleasant Radio Astronomy Observatory University of Tasmania, Geoscience Australia 

Figure 1. The Mt Pleasant 26m antenna 

2003, Hobart was the first station to switch from reel to reel tapes to using Mark 5 recording media 

only for geodetic experiments correlated at Bonn, Washington and Haystack. Syowa experiments, 

correlated at Mitaka, are recorded using S2 media. During 2003 the station’s Hi-Ranger elevated 

work platform tower had its 10 year major overhaul done to enable continued safe work at heights. 

5. Future Plans 

We will have two new academic staff members commencing in 2004. Also, as a part of the 

(ARC) linkage funding, we plan to have a PhD student in geodetic VLBI commencing. The 

stations existing humidity, temperature and pressure sensors will be replaced in early 2004 by a 

more accurate MET3 sensor funded by NAOJ. 

46 IVS 2003 Annual Report 
Kashima Space Research Center, Communications Research Laboratory Kashima 34m Radio Telescope 

Kashima 34m Radio Telescope 

Junichi Xakajima, Eiji Kauai, Hitoshi Takeuchi, Hiroo Osaki, ffiromitsu Ku boki 

Abstract 

In April 2004, Communications Research Laboratory (CRL) will be re-organized into National 

Institute of Information and Communications Technology (NICT. Figure 1). nom a policy to promote 

communication technology and related science, NICT will double its scale in number of staff and 

research budget. In NICT. VLBI is getting more important application to handle huge amount data 

transfer as well as its scientific results. There is no change in Kashima Space Research Center under 

the NICT. This network station report is mainly focused to telescope related projects in 2003. 

1. Introduction 

Communications Research Laboratory (CRL) constructed the Kashima 34m telescope in 1988 

(Figure 2). The telescope is located 100 km east of Tokyo. During 15 years operation, the telescope 

is kept in good condition and joined VLBI and single-dish observations. The 34m telescope is 

operated by Radio Astronomy Applications Group. 

Nii T National Institute 

Information and 

Communications 

Technology 

of 

Figure 1. NICT, new institute log0 reorganized from CRL Figure 2. The Kashima 34m radio telescope. 

2. Telescope Status 

2.1. Conventional Back-end System and Field System 

As a role of VLBI technology development center, TDC, Kashima 34m is particular site with 

functions where all kind of back-ends are gathered. Currently, G-bit (1024Mbps), K-4 (256Mbps), 

K3-A (MarkIIIA compatible), VSOP, and 5-2 VLBI magnetic tape systems are available. K4, 

VLBA and S2 are controlled from the Field System (FS-9) together as well as 34m telescope. The 

FS-9 functional enhancement are done by the Kashima group. Weather monitoring logging system 

was renewed. As for single dish observation, there are two AOS systems in operation. One is the 

Pulsar AOS timing measurement system. The another is multi purpose AOS spectrometer. Please 

see the AOS details in previous Annual Reports. Latter AOS system will be moved to digital 

spectrometer using K5/PC-VSI. New weather monitoring and logging system were installed. 

IVS 2003 Annual Report 47 
Kashima 34m Radio Telescope Kashima Space Research Center, Communications Research Laboratory 

2.2. New VLBI Back-end, Unified K5-series 

New PC-based VLBI system become popular to support VLBI observations. Two PC-based 

VLBI system had been developed at CRL. These are system up to 256 Mbps and 2048 Mbps. In 

2003, both system are unified under name of K5 (Figure 3). 

We have developed K5/PC-VSSP narrow band multi-channel system to substitute system up 

to 256 Mbps. The K5/PC-VSSP is unique since each unit is integrated with on board 4channel 

AD converters. Four 4-channel K5/PC-VSSP units are equivalent to conventional 16-channel 256 

Mbps VLBI system. With the matured 256-Mbps data rate, the K5/PC-VSSP system was used 

in Nozomi spacecraft positioning, geodetic and ERP observations. Different from magnetic tape 

recorders, the PC-based K5/PC-VSSP can also perform data correlation. K5 correlation software 

packages are completed and distributed to sites. In this view, K5/PC-VSSP is hardware and 

software in a single body. K5 correlation software is used at JIVE correlator. Speed of these 

software is increasing and GRID cluster PC system under development enables real-time VLBI 

experiment. Results from K5 correlation software is directly connected to analysis software and 

provide reliable results. 

Another new VLBI back-end is K5/PC-VSI system for high speed VLBI acquisition. Two 

high-speed AD samplers ADS-1000 (lch, 1024 M-Sps, 2048 Mbps) and ADS-2000 (16ch, 64 MSps, 2048 Mbps) are prepared for K5/PC-VSI. Essential of K5/PC-VSI is that the components are 

using VSI interface which is internationally specified. Successive K5/PC-VSI recording system can 

capture the high-speed interface data up to Gbps to normal Linux file system. With this K5/PCVSI system acquired G-bps data can be transmitted via network or processed simultaneously. 

These multi task features during recording are achieve by well designed PCI-X interface board 

(PC-VSI2000DIM, digitallink co. ltd.) and newly invented Linux device driver ability. To handle 

huge amount of Gbps data stored to T-Byte disk-array, high speed software correlation core is 

developed separately. By recent CPUs Intel Xeon series, the core reached performance of 100 

Mbps processing. This means multiple CPU and small number of cluster PCs will reach real-time 

processing of G-bps data. 

PC-VSI 1 ch-wide /16ch AD gico3 soft 

astronomy 512-2048Mbps GRID corr. 

Figure 3. K5 unified character descended from two PC based e-VLBI system. 

3. Telescope Status 

3.1. Receiver Systems 

Receivers in Kashima 34m telescope are L, C, K, Ka, Q and S/X band. The Ka and K receivers 

are integrated to a dual-band dewar. These receiver performances are summarized in Table 1. 

Efficiency of Ka receiver is still provisional. Please see receivers details in previous Annual Report. 

48 IVS 2003 Annual Report 
Kashima Space Fi.esearch Center, Communications Research Laboratory Kashima 34m Radio Telescope 

Table 1. Fkeiver Specification of the 34m Radio Telescope. 

Band frequency(Hz) Trx(K) Tsys(K) Efficiency Polarization 

L 1350- 1750 18 43 0.68 R/L 

S 2210-2350 19 83 0.65 R/L 

C 4600-5100 25 108 0.70 L(R) 

X 7860-8680 41 52 0.68 R/L 

K 21800-23800 75 160 0.5 L(R) 

Ka 31700-33700 85 150 0.4 R(L) 

Q 42300-44900 180 300 0.3 L 

3.2. RFI Mitigation (Interference) 

IMT-2000, mobile phone base stations, in Sband once saturated the receiver system in Kashima 

34m telescope. To avoid interference from transmitters, we have developed cooled HTS (High 

Temperature Super-conductor) filters. The sharp cutoff filter skirt of -3OdF3/MHz enabled us to 

receive lower Sband adjacent to IMT-2000 allocation. The filter is integrated into maintenance 

free refrigerator cryogenics. See details in TDC Newsletters from CFU. 

3.3. Mechanical System 

Continuous effort was put into telescope up-grading. Part of feed control was replaced to 

Ether basis. Extra EL and AZ motors were purchased. Encoder electrical units under heating 

environment were newly produced. MTBF of telescope components are carefully checked, inspected 

and they are replaced before failure. Key components are ready to change immediately in trouble. 

Accurate sub-reflector re-alignment tools are developed for annual maintenance. Usually position 

sub-reflector parameters are af€ected after mechanical overhaul. This year, positioning accuracy 

less than 0.1 mm is realized by the caliper like alignment tool. As a result parameter adjustment 

observation before start up mm-wave observation was reduced to a few days after maintenance. 

Table 2. Mechanical Specification of the 34x11 Radio Telescope. 

Maximum Speed Azimuth(deg/sec) 0.8 

Maximum Speed Elevation(deg/sec) 0.64 

Drive Range Azimuth(deg) +-270 

Drive Range Elevation(deg) 7- 90 

Operation Wind Speed (m/s) 13 

Panel Surface Accuracy r.m.s.(mm) 0.17 

4. On-going Projects and Major Results of 2003 

e-VLBI (Domestic K5 experiment series) Sessions to verify K5 VLBI system were completed. In 2003, comparison between K4 and K5 proved K5 data quality and output vaIVS 2003 Annual Report 49 
Kashima 34m Radio Telescope Kashima Space Research Center, Communications Research Laboratory 

lidity. The K5 results well agreed with K4 and they increased sensitivity. Koganei llm and 

Kashima llm telescope remotely operated sites were in the experiment too. K5 1024 Mbps 

observation are carried out at the same time. Universities telescopes related observations 

are increased too. New telescope Yamaguchi 32m and Tomakomai llm are operated by 

small university groups. CRL had been technically supporting these groups and carried out 

e-VLBI experiment series with these stations. 

e-VLBI (International K5 experiment series) Monthly IVS-T and IVS-CFtF sessions are 

scheduled at Kashima 34m. Though these observation are recorded to tapes, K5 system 

captured the observations too. Part of the observation data was transferred to Haystack 

and Washington correlator via the Internet. The VLBI data is processed as well as the tape 

data. This is a step to regular e-VLBI without tape shipping. Another successful international observation has been carried out with Finland. K5 2-Gbps observations were carried 

out with Metsahovi observatory. Software correlations are running at both site. Distributed 

correlation architecture utilize network bandwidth between the stations. 

NOZOMI observation Satellite positioning by relative VLBI technique has become a strong 

demand to VLBI group in this decade. Positioning software and hardware package development is one of main mission in Kashima Radio Astronomy Applications group. In year 2003, 

series of experimental observations are carried out targeting NOZOMI spacecraft to Mars 

and initial VLBI positioning results were produced. Usuda 64m, Kashima 34m, Tsukuba 

32m, universities telescopes and Algonquin joined these sessions. CRL group processed the 

data rapidly and ISAS NOZOMI operation group referred the results. The spacecraft finally 

completed its swing-by maneuver. After the NOZOMI, HAYABUSA spacecraft toward a 

minor planet needs same VLBI positioning technique. Accuracy and performance of this 

satellite positioning VLBI system is improving. Here the PC-based e-VLBI realized flexible 

numerical processing and data correlation too. 

Pulsar, J-Net, VERA and other projects Long-term periodical observation of pulsars revealed the stability nature in Allan variance. Japanese domestic astronomical VLBI observation, J-Net increased ability with National Astronomical Observatory’s VERA stations. 

Kashima 34m and Nobeyama 45m are requested to join their observations to boost sensitivity. 

Kagoshima university group carried out spectral observation at 22 GHz and 43 GHz. 

5. Outlook and Technical StafF 

As a VLBI station in network era, Internet bandwidth will become important infrastructure 

in advanced experiment. 10-Gbps access network to back-bone node is planned to be installed at 

Kashima Space Research Center. Engineering and Technical staff who take charge of Kashima 

34m telescope are Eiji Kawai (leader of all operations and maintenance), Hiroshi Takeuchi (scientific engineer), Hiroo Osaki (software engineer), Hiromitsu Kuboki (RF and mechanical technician), and Yuki Watanabe, Yujiro Hirose (Contracter Rikei Corp., Vertex TIW). Tetsuro Kondo 

(kondo@crl.go.jp) is the supervisor of all Kashima 34m project. 

50 IVS 2003 Annual Report 
c 

Kashima Space Research Center, CFU Kashima and Koganei 11-m VLBI Stations 

Kashima and Koganei 11-m VLBI Stations 

Yasuhiro Koyama 

Abstract 

Two 11-m VLBI stations at Kashima and Koganei used to be a part of the Key Stone Project VLBI 

Network. The nehmrk consisted of four VLBI stations at Kashima, Koganei, Miura, and TatSince Miura and Tateyama stations have been transported to Tomakomai and Gib, Kashima and 

Koganei 11-m stations are remaining as JVS Network Stations. After the regular VLBI sessions with 

the Key Stone Project VLBI Network terminated in 2001, these stations are mainly used for the 

purposes of technical developments and various observations. In the year 2003, three geodetic VLBI 

sessions were performed to evaluate the performance of the K5 and Gigabit VLBI systems. Many 

observations were also performed to determine precise orbit of the Nozomi and Hayabnsa spacecraft. 

1. Introduction 

The Key Stone Project (KSP) was a research and development project of the Communications 

Research Laboratory [l]. Four space geodetic sites around Tokyo were established with VLBI, 

SLR, and GPS observation facilities at each site. The locations of the four sites were chosen 

to surround Tokyo Metropolitan Area to regularly monitor the unusual deformation in the area 

(Figure 1). Therefore, the primary objective of the KSP VLBI system was to determine precise site 

positions of the VLBI stations as frequently and fast as possible. To realize this objective, various 

new technical advancements were attempted and achieved. By automating all of the process from 

the observations to the data analysis and by developing the real-time VLBI system using high 

speed digital communication links, unattended continuous VLBI operations were made possible. 

Daily continuous VLBI observations without human operations were actually demonstrated and 

the results of data analysis were made available to public users immediately after each VLBI 

session. Improvements in the measurement accuracies were also accomplished by utilizing fast 

slewing antennas and by developing higher data rate VLBI systems operating at 256 Mbps. 

135 E 140 E 145 E 

Figure 1. Geographic locations of four KSP VLBI stations and two stations at Tomakomai and Gifu. 
Kashima and Koganei 11-m VLBI Stations Kashima Space Research Center, CRL 

11-m antenna and other VLBI facilities at Miura and Tateyama stations have been transported 

to Tomakomai Experimental Forest of the Hokkaido University and to the campus of Gifu University, respectively. As a consequence, two 11-m stations at Kashima and Koganei (Figure 2) are 

remaining as IVS Network Stations. After the regular VLBI sessions with the Key Stone Project 

VLBI Network terminated in 2001, 11-m VLBI stations at Kashima and Koganei are mainly used 

for the purposes of technical developments and various observations. 

Figure 2. 11-m VLBI antennas at Kashima (Left) and Koganei (Right). 

2. Activities in 2003 

For technical developments, the baseline between Kashima and Koganei is now used as a test 

bed for IP-based real-time VLBI observations. The two stations used to be connected by high speed 

ATM (Asynchronous Transfer Mode) network with a collaboration with the NTT Laboratories until 

July 2003. The ATM connection was temporarily terminated and the two stations are currently 

connected at a maximum speed of 100 Mbps. The network is shared by the usual traffic of the 

Communications Research Laboratory and is an ideal technical test-bed for e-VLBI under the 

shared network environment which will be inevitable in connecting most VLBI sites in the world. 

Regarding conventional geodetic VLBI experiments, four sessions listed in Table 1 were performed in 2003. The CUTE04 session was performed as a series of geodetic VLBI experiments to 

determine precise positions of the Tomakomai and Gifu VLBI stations. CUTE is the acronym of 

the CRL and University Telescopes Experiment. The observations were made with the K4 VLBI 

system at a data rate of 256 Mbps. GEXOll session was performed to evaluate the Gigabit VLBI 

system and observations were conducted for only six hours with Kashima 11-m and Tomakomai 

11-m stations. The other two VLBI experiments were performed by using three different VLBI 

systems. In the U03031 session, the K5 VLBI system and the Gigabit VLBI system were used 

at Kashima and Koganei 11-m VLBI stations in addition to the K4 VLBI system. The JD0306 

session is one of the routine domestic VLBI sessions conducted by Geographical Survey Institute 

52 IVS 2003 Annual Report 
Kashima Space Research Center, CRL Kashima and Koganei 11-m VLBI Stations 

(GSI). 11-m VLBI stations at Kashima, Tomakomai, Gifu and 32-m VLBI station at Yamaguchi 

participated in the session in addition to the three GSI VLBI stations at Tsukuba, Chichijima, and 

Aira. The K5 VLBI system was used at five stations, i.e. Kashima, Tsukuba, Tomakomai, Gifu, 

and Yamaguchi in addition to the K4 VLBI system except for the Yamaguchi station where only 

the K5 VLBI system was used. At Kashima and Tomakomai stations, the Giga-bit VLBI system 

was also used in parallel. The results from these two sessions were compared between different 

systems and the expected performance of the K5 VLBI system and the Giga-bit VLBI system were 

cobed [2]- 

Table 1. Geodetic VLBI sessions conducted in 2003. 

Session Date Participating stations 

U03031 

CUTE04 March 12 Kashima (11-m), Tomakomai (11-m), Gifu (11-m) 

GEXOll July 15 Kashima (11-m), Tomakomai (11-m) 

JD0306 July 16 Kashima (11-m), Tomakomai (11-m), Yamaguchi (32-m) , 

January 31 Kashima (11-m and 34m), Koganei (11-m), Usuda (am), 

Gifu (11-m), Tsukuba (32-m) 

Gifu (11-m), Tsukuba (32-m), Aira (11-m), Chichijima (11-m) 

The two 11-m stations at Kashima and Koganei were also used for VLBI observations of the 

spacecraft Nozomi and Hayabusa in 2003. Nozomi is the spacecraft of Japan Aerospace Exploration 

Agency (JAXA) launched in 1998 to explore the planet Mars, whereas Hayabusa is the spacecraft 

of JAXA launched in 2003 to explore the asteroid Itokawa. Since precise orbit determination of the 

spacecraft Nozomi was required before the find Earth swing-by in June 2003, VLBI observations 

of the spacecraft Nozomi were carried out. Many VLBI stations in Japan including the 11-m 

VLBI stations at Kashima and Koganei, and the VLBI station at Algonquin participated in the 

observations. In total, 34 VLBI sessions were performed in 2003. The spacecraft Hayabusa is 

expected to arrive at the asteroid Itokawa in 2005 and precise orbit determination of the spacecraft 

will be essential to make the mission successful. In 2003, several observations were made mainly to 

survey adequate celestial radio sources for differential VLBI observations to be used in the critical 

observations which will be performed in 2004 and 2005. 

3. StafF Members 

The 11-m antenna stations at Kashima and Koganei are operated and maintained by the Radio Astronomy Applications Group at Kashima Space Research Center, Communications Research 

Laboratory. The staff members of the group are listed in Table 2. The operations and maintenance 

of the 11-m VLBI station at Koganei is also greatly supported by the Optical Space Communications Group at Koganei Headquarters of CRL. We are especially thankful to Dr. Hitoshi Kiuchi 

and Dr. Yoshinori Arimoto for their support. 

4. Future Plans 

The current network connection between Kashima and Koganei is limited to a maximum speed 

of 100 Mbps, but the speed will be upgraded to 10 Gbps in April 2004. The connection from 

~ 

IVS 2003 Annual Report 53 
Kashima and Koganei 11-m VLBI Stations Kashima Space Research Center, CRL 

Table 2. Staff members of Radio Astronomy Applications Group, KSRC, CRL 

Name 

Tetsuto KONDO 

Eiji KAWAI 

Yasuhiro KOYAMA 

Ryuichi ICHIKAWA 

Junichi NAKA JIMA 

Mamoru SEKIDO 

Hiro OSAKI 

Hiroshi TAKEUCHI 

Moritaka KIMURA 

Hiromitsu KUBOKI 

Main Responsibilities 

Group Leader 

Antenna System 

International e-VLBI 

Spacecraft Orbit Determination 

High Data Rate VLBI System 

Spacecraft Orbit Determination 

International e-VLBI 

Antenna System 

High Data Rate VLBI System 

Antenna Svstem 

Koganei to the TransPAC was upgraded to 1 Gbps in 2003. We are planning to perform eVLBI observations under collaboration with Haystack Observatory by using the improved network 

connect ions. 

The S/X receivers of the 11-m antenna at Tomakomai was removed to install the new 22 GHz 

receiver to the antenna system. As a result, CUTE sessions will only be performed with three 

VLBI stations at Kashima, Koganei, and Gifu. Instead, 22 GHz VLBI observations will be made 

with Kashima 34-m VLBI station and the Tomakomai 11-m VLBI station after the new 22 GHz 

receiver is installed on the Tomakomai station. 

In 2004, we are planning to continue VLBI observations toward the spacecraft Hayabusa for its 

precise orbit determination. The use of phase delay measurements will be investigated to improve 

the accuracy and precision of the determination of the orbit. 

Currently, the antenna system and the VLBI facilities are controlled by the automated VLBI 

observation system developed for the Key Stone Project. The system is running on the relatively 

old Unix operating system and we are planning to use FS9 in the future. As of January 2004, we 

have succeeded to control the antenna system from the FS9 software and we expect we can use the 

FS9 software for VLBI sessions at two 11-m VLBI stations at Kashima and Koganei in the future. 

In April 2004, Communications Research Laboratory will be integrated with the Telecommunications Advanced Organization of Japan (TAO) and the new institute will be established. The 

name of the institute will be National Institute of Information and Communications Technology 

and the VLBI activities in the CRL will be continued under the new institute. 

References 

[l] Special issue for the Key Stone Project, J. Commun. Res. Lab., Vol. 46, No. 1, March 1999 

[2] Koyama, Y., T. Kondo, H. Osaki, K. Takashima, K. Sorai, H. Takaba, and K. Fujisawa, IVS CRL 

TDC News, No. 23, Nov. 2003, pp. 26-30 

54 IVS 2003 Annual Report 
USNO and NASA GSFC Kokee Park Geophysical Observatory 

Kokee Park Geophysical Observatory 

Clyde A. Cox 

Abstract 

This report summarizes the technical parameters and the technical staff of the VLBI system at 

Kokee Park on the Island of Kauai. Included is an overview of the VLBI activities for the year 2003. 

1. KPGO 

Kokee Park Geophysical Observatory is located on the bland of Kauai in the Hawaiian Islands; 

Kauai is the most northwestern (inhabited) Island. The site is in a State Park (Kokee State Park) 

hence its name. It is located at an elevation of 1100 meters near the Waimea Canyon, which is 

often referred to as the Grand Canyon of the Pacific. 

Kokee Park Geophysical Observatory first participated in VLBI operations as part of the GAPE 

experiments in 1984. At that time the station was part of NASA's STDN (Satellite ?facking Data 

Network). The 4m system was modified by installing a focal point receiver, hydrogen maser, 

data acquisition terminal, tape drive and computer system. This was operational for the summer 

of 1984. The system was removed after the GAPE '84 experiments and reinstalled again for the 

summer of 1985. It was not until 1986 that we became a continuous participant in VLBI operations. 

In October 1989 NASA phased out the STDN operation on Kauai and the station was transferred to the Crustal Dynamics Project at the Goddard Space Flight Center. The station started 

weekly operation for the U.S. Naval Observatory as part of the NAVNET network. 

Early in 1992 construction of USNO's present 20-meter antenna was started. The foundation 

work was completed in August 1992 and the structure was started in September just as Hurricane 

Iniki struck on September 11, 1992. Installation was completed in 1993 and first light was in June 

1993. Later in 1993 the use of the Smeter system was discontinued. 

Starting in July 2000 Kokee Park began daily (Monday through Friday) participation in the 

Intensive schedule for USNO. 

S-2 recorder system was installed in 2000. 

Mark IV system was installed during 2001. 

In May of 2002 Mario B6rubd and Bill Petrachenko arrived on site for installation and testing 

of a S-2 DAS. We have since that time supported the E3 series of experiments on a monthly basis. 

In May of 2002 Kokee Park received a Mark 5 system which was first run in parallel with the 

tape drive during the daily Intensive sessions (three times a week). Correlation was first done at 

Haystack; after several weeks of comparison we then started to ship the disk to USNO. During 

CONTO2 the Mark 5 was used in stand alone mode. Switching between Intensive sessions and 

other experiments became a pleasure. 

During November 2002 the survey team was on station to verify our antenna footprint and to 

survey the new (replacement) Doris beacon antenna. 

A new MET package (MET3) was installed in February 2003. 

IVS 2003 Annual Report 55 
Kokee Park Geophysical Observatory USNO and NASA GSFC 

Figure 1. Kokee Park Geophysical Observatory 9m & 20m antennas. 

Table 1. Location and Addresses of Kokee Park Geophysical Observatory 

Longitude 159.665' W 

Latitude 22.126' N 

Kokee Park Geophysical Observatory 

P.O. Box 538 Waimea, Hawaii 96796 

2. Technical Parameters of the VLBI System at KPGO 

The receiver is of NRAO (Green Bank) design (dual polarization feed using cooled 15 K HEMT 

amplifiers). The DAR rack and tape drive were supplied through Green Bank. The antenna is of 

the same design and manufacture as those used at Green Bank and Ny-hesund. 

The technical parameters of the radio telescope are summarized in Table 2. 

Timing and frequency is provided by a Sigma Tau Maser with a NASA NR Maser providing 

backup. Monitoring of the station frequency standard performance is provided by a CNS (GPS) 

56 IVS 2003 Annual Report 
USNO and NASA GSFC Kokee Park Geophysical Observatory 

Receiver/Computer system. The Sigma Tau performance is also monitored via the IGS Network. 

3. Technical Staff of the VLBI System at KPGO 

The staff at Kokee Park consists of six people who are employed by Honeywell under contract 

to NASA for the operations and maintenance of the Observatory. VLBI operations are conducted 

by Kelly Kim, Matt Harms, and Kawika Fujita. 

4. Status of KPGO 

Kokee Park has participated in many VLBI experiments since 1984. We started observing with 

GAPE, continued with NEOS and CORE, and are now in IVS R4 and R1. We also participate in 

the RDV experiments. 

We averaged 1.5 experiments per week during calendar year 2000 and increased to an average 

of 2 experiments of 24 hours each week with daily Intensive experiments during year 2002 and into 

2003. 

Kokee Park also hosts other geodetic measurement systems, including PRARE, a DORIS beacon, and a TurbeRogue GPS receiver. Kokee Park is an IGS station. 

5. Outlook 

e-VLBI was expected to make its debut during the first part of 2003. However, we are delayed 

due to the common "last Mile" problem. Now with the year starting we are seeing light at the end 

of the tunnel, tests are starting to show a transfer rate of up to 85 Mbps (using UDP) to Haystack. 

Figure 2. Kokee Park also hosts other systems; DORIS Beacon, PRARE, and IGS (GPS). 

IVS 2003 Annual Report 57 
Kokee Park Geophysical Observatory USNO and NASA GSFC 

S-band 

(reference v = 2.3GHz, X = 0.1304m) 

T&JS 

SSEFD (CASA) 

rl 

VLBI terminal type 

recording media 

G/T 

Table 2. Technical parameters of the radio telescope at KPGO. 

2.2 - 2.4GHz 

40 K 

665 Jy 

35.15 dB/K 

0.539 

thin-tape only 

VLBA/VLBA$-MARK5 

Parameter 

Field System version 

~~ 

owner and operating agency 

year of construction 

radio telescope system 

receiving feed 

diameter of main reflector d 

focal length f 

surface contour of reflector 

azimuth range 

azimuth velocity 

azimuth acceleration 

elevation range 

elevation velocity 

elevation acceleration 

f Id 

9.6.9 

Kokee Park 

1993 

Az-E1 

primary focus 

20m 

8.58m 

0.43 

0.020inchesrms 

0.. .540° 

USNO-NASA 

201s 

10/2 

2O/S 

1012 

0.. .goo 

X-band I 8.1 - 8.9GHz 

(reference v = 8.4GHz, X = 0.0357m) 

40 K 

900 Jy 

45.05 dB/K 

0.406 I I 

58 IVS 2003 Annual Report 

~~ ~ ~~ 
Agenzia Spaxiale Italiana Matera CGS VIBI Station 

Matera CGS VLBI Station 

Giuseppe Colucci, Domenico Del ROSSO, Lucian0 Garramone 

Abstract 

This report summarises the VLBI activities performed at the Matera \LBI station[l]. Also an 

overview of the technical characteristics of the system and some staff addresses will be given. 

1. General 

The Matera VLBI station is located at the Italian Space Agency “Centro di Geodesia Spaziale” 

(CGS) near Matera, a small town in the South of Italy. The CGS came into operation in 1983 when 

a Satellit 

Figure 1. The Matera “Centro di Geodesia Spaziale” (CGS) 

Laser Ranging SAO-1 System was installed at CGS. Fully integrated in the worldwid -- 

network, SAO-1 has been in continuous operation &om 1983 up to 2000, providing high precision 

ranging observations of several satellites. The new Matera Laser Ranging Observatory (MLRO), 

the most advanced Satellite and Lunar Laser Ranging facility in the world, has been installed 

in 2002 and has replaced the old SLR system. CGS hosted also mobile SLR systems MTLRS 

(Holland/Germany) and TLRS-1 (NASA). 

In May 1990 the CGS extended its capabilities to Very Long Baseline Interferometry (VLBI) 

installing a 20-m radiotelescope. Since then, Matera performed 634 sessions up to December 

2003. In 1996 the receiver was upgraded to standard wideband and at the end of 1999 a Mark N 

formatter and decoder were installed by MIT Haystack. 

IVS 2003 Annual Report 

, 

59 
Matera CGS VLBI Station Agenzia Spaziale Italiana 

Input frequencies 

Noise temperature 

In 1991 we started GPS activities, participating in the GIG 91 experiment installing in Matera 

a permanent GPS Rogue receiver. In 1994 six TurboRogue SNR 8100 receivers were purchased in 

order to create the Italian Space Agency GPS fiducial network (IGFN). At the moment 12 stations 

are part of the IGFN and all data from these stations, together with 15 other stations in Italy, are 

archived and made available by the CGS WWW server GeoDAF (http://geodaf.mt.asi.it). 

Thanks to the colocation of all precise positioning space based techniques (VLBI, SLR, LLR, 

GPS and PRARE), CGS is one of the few “fundamental” stations in the world. With the objective 

of exploiting the maximum integration in the field of Earth observations, in the late 1980s AS1 

extended CGS involvement also in remote sensing activities for present and future missions (ERS-1, 

ERS- 2, X- S AR/ SIR- C, SRTM, ENVIS AT). 

S/X 2210 MHz to 2450 MHz / 8180 MHz to 8980 MHz 

S/X <20K 

2. Technical/ Scientific 

v 

IF output frequencies 

IF Output Power with 300 K 

The Matera VLBI antenna is a 20-meter dish with a cassegrain configuration and AZ-EL 

mount. The AZ axis has f270 degrees of available motion. The slewing velocity is 2 deg/sec for 

both AZ/EL axis. 

The technical parameters of the Matera VLBI antenna are summarised in Table 1. 

The Matera time and frequency system is composed of three frequency sources (two Cesium 

beam and one H-maser standard) and three independent clock chains. The EFOS-8 H-maser from 

Oscilloquartz is used as a frequency source for VLBI. 

The control computer is a SWT Pentium/233 PC running Linux and FS version 9.6.9. 

S/X 

S/X 

190 MHz to 430 MHz / 100 MHz to 900 MHz 

0.0 dBm to +8.0 dBm 

Table 1. Matera VLBI Antenna Technical Specifications 

at the input flange 

Gain comDression S/X <1 dB at +8 dBm output level 

I at dewar flange I I I 

vu 

Inter modulation products S/X At least 30 dB below each of 2 carriers 

at an IF outDut level of 0 dBm Der carrier 

Tsys 

SEFD 

lImaee reiection I S/X 1 >45 dB within the IF passband I 

S/X 55/65 K 

SIX 800/900 Jv 

3. StafF 

The list of the VLBI staff members of Matera VLBI station is provided in Table 2. 

60 IVS 2003 Annual Report 
Agenzia Spaziale Italiana Matera CGS VLBI Station - 

Name Agency 

Ing. Lucian0 Garramone AS1 

Domenico Del Ross0 Telespazio 

Giuseppe Colucci Telespazio 

Activity EMail 

VLBI Manager 1uciano.garramoneQasi.it 

Operations Manager domenico-delrosso@telespazio.it 

VLBI contact giuseppe.colucci@asi.it 

4. Status 

Table 3 summarizes the sessions performed during 2003. Figure 2 shows the summary of 

acquisition up to December 2003 in terms of hours of acquisition. During this year, mainly 2 

problems afllicted the VLBI acquisition at Matera. 

- Up to February 3 (R1056), no fringes were found on Matera tapes. Cause was traced to 

a problem with the GPS receiver used to measure the formatter time. After the problem was 

identified, R1055 session (January 27) was included in the correlation and fkinges were found. 

- In Semptember and October, Matera did not observe due to a severe problem discovered on 

the antenna rail. Acquisition restarted after a temporary fix. 

I 

TotPl haurs 

OK 111 Lost 

I 

amm 

iscum 

b 

0 I imm 

5 

nom 

om 

Figure 2. Summary of acquisition from May 1990 to December 2003 

5. Outlook 

In first months of 2004, Mark 5 recorder will be installed. Seven disks pack modules have been 

Heavy work on the antenna rail will be planned to definitively fix the rail problem. 

purchased to be included in the IVS pool. 

IVS 2003 Annual Report 61 
Matera CGS VLBI Station Agenzia Spaziale Italiana 

January 3 (2-lost) 2 (2-lost) 

Februar 3 (1-lost) 2 

March 5 4 

5 

5 

1 1 1 12 

1 TOTAL (44 I27 12 16 14 1 83 

References 

[l] G.Colucci, D.Del ROSSO, E.Lunalbi, M.Paradiso: “Matera VLBI Station Report on the Operational and 

Performance Evaluation Activities from January to December 2003”, available soon at this address: 

http: / /geodaf.mt .asi .it /html /survrep.html 

62 IVS 2003 Annual Report 
Istituto di Radioastronomia, Medicina Medicina Network Station 

The Medicina Station Status Report 

Alessandro Orfei, Franc0 Mantovani, Pierguido Sarti 

Abstract 

The activities done at the Medicina radio astronomy station are briefly summarized. Those activities 

=re mainly related to the geodetic VLBI observations and to the upgrading of the 32-m dish. 

1. Main Activities at the Medicina Station 

The activities at the Medicina Station were mainly addressed to improve the data acquisition 

quality. Most of the upgrading work was done in the electronic hardware and to improve the 

efficiency of the 32-m dish. Great care was also taken to increase the reliability of the station 

during VLBI sessions. 

1.1. The Upgrade of the 32-m Dish 

The Medicina 32-m dish has been heavily upgraded during Summer 2003. A new antenna servo 

system has been installed. This uses modern components and digital electronics. A higher degree 

of reliability and less maintenance interventions are expected. The software developed for pointing 

and traching of the antenna has been adapted to the new system. 

All the cables routing on the antenna were changed after over 20 years of the antenna observing 

activities. Together with usual metallic wires, high quality coaxial cables were installed together 

to several fiber optics links. 

The vertex cabin was fully renewed. A completely new mechanical structure was installed to 

allow the allocation of many receivers at the same time as part of a long term plan to achieve full 

frequency agility of the telescope. This is the second step of that plan, which is related to the 

secondary focus of the antenna. In the first step, a robotic system was implemented to shift the 

secondary mirror of the telescope under computer control. The same system also allowed the shift 

of the primary focus receiver box which hosts the 22 GHz, S/X and 1.6 GHz receivers. Moreover, a 

new control hardware was installed in order to check housekeeping data coming from the receivers 

and allowing the switching among receivers hated in the secondary focus receiver cabin. 

1.2. The Mark 5 recording system 

The prototype version of the new Mark 5 system, delivered in 2002 from Haystack, was up 

graded to Mark 5A. The present status of the Mark 5 system looks fine. Many tests were done 

with good results. One of the tests implied the transferring of data from the Bologna gate of the 

backbone to the JIVE Correlator in Dwingeloo, via the high data rate GARR/GEANT network. 

Disks and disks enclosures were acquired. Four (4) modules are available now with 8x 120 GB 

disks each and 4 modules with 8x250 GB disks are going to be assembled. Twenty more empty 

modules are available at the station ready to be filled with disks. 

~~ 

IVS 2003 Annual Report 63 
Medicina Network Station Istituto di Radioastronomia, Medicina 

Figure 1 - Left: View of the cover of the vertex room. Eight receivers can be permanently 

mounted, one for each of the external holes. The hole on-axis will host receivers under test. Right: 

View of the top of the vertex room. 

1.3. Development of Control Software 

In-house codes have been written to keep under control the status of the Mark 5 operations. 

The new software is under test at the moment. 

On request of the European VLBI Network Technical Operation Group, a dedicated software is 

under development to keep under control the recording tracks of the Mark 4/Mark 5 systems. As 

soon as the software is ready, it will be made available to the EVN stations and to any interested 

IVS station on request. A beta version is available and under test. 

1.4. Geodetic Activities 

a) VLBI Observations 

During 2003, the Medicina 32-m dish has taken part in 10 geodetic VLBI observations namely 

IVS-T, RDV and EUROPE projects. Due to delays in the upgrading, the antenna could not 

observed during three sessions in September 2003 as originally scheduled. One more project was 

skipped by the IVS Coordinating Center in December. 

b) Local Survey 

In September 2003 the VLBI Reference Point (RP) in Medicina has been surveyed for the 

64 IVS 2003 Annual Report 
Istituto di Radioastronomia, Medicina Medicina Network Station 

fourth time. It has also been the third determination of the IGS-GPS RP and consequently of 

the GPS-VLBI eccentricity. A method based on Classical Geodesy measurements for determining 

eccentricities between celocated space geodesy techniques has been developed and tested on the 

data acquired during the three surveys (Sarti et al. 2004). In Table1 eccentricity values for the 

three surveys expressed in a local frame are shown. The variability of the yearly estimated 

Table 1. Local tie 

Eccentricity 2001 2002 2003 

XVLBI(m) 45.5356f0.0003 45.5360f0.0002 45.5348f0.0001 

YVLBI (m) 21.5805f0.0oO4 21.5825f0.0003 21.5764f0.0001 

ZVLBI(m) 17.6995f0.0008 17.7024f0.0006 17.7003f0.0003 

XGPS (m) 29.9692f0.0010 29.9692f0.0008 29.9840f0.0003 

YGPS (m) 79.9215f0.0011 79.9268f0.0006 79.9209f0.0003 

ZGPS (m) 0.5699f0.0008 0.5701f0.0005 0.5684f0.0003 

coordinates of both endpoints of the eccentricity vector suggests an instability of the pillars used 

to define the local frame. This latter is defined fixing its planimetric origin on pillar P3 (recently 

assigned IERS DOMES number: 12711M006) while its altimetric origin is fixed on pillar G7. 

Only two other pillars (P1 and P2 with IERS DOMES numbers 12711M004 and 12711M005, 

respectively) establish the local ground control network. In Table 2 coordinates of markers P1, P3 

and G7 obtained adjusting terrestrial observations acquired during 2001, 2002 and 2003 surveys 

are shown. 

1 

Table 2. Survey 

Coordinates 

(fixed) 

ywm) 

ZPl(m) 

XP3(m) (fixed) 

YP3(m) (fixed) 

ZP3(m) 

XG7(m) 

YG7(m) 

ZG7(m) (fixed) 

2001 

0.0 

42.6586f0.0002 

2.0772f0.0003 

0.0 

0.0 

2.0195f0.0003 

6.1261fO.OOO5 

72.7897f0.0006 

0.0 

2002 

0.0 

42.6628f0.0002 

2.0783f0.0003 

0.0 

0.0 

2.0177f0.0003 

6.1309f0.0002 

72.7924f0.0002 

0.0 

2003 

0.0 

42.6636f0.0002 

2.0772f0.0002 

0.0 

0.0 

2.0154f0.0003 

6.1386f0.0003 

72.7907f0.0003 

0.0 

It is therefore urgent to enlarge the local ground control network adding properly positioned 

pillars so as to ensure a high stability of the local frame. This activity has been planned for spring 

IVS 2003 Annual Report 65 
Medicina Network Station Istituto di Radioastronomia, Medicina 

2004 when at least three new triplets of pillars will be added to the local network. A detailed 

geological survey is also scheduled in order to complete the relevant set of information regarding 

the stability at the observatory and distinguish between local scale and large scale movements. 

Considerations on local soil characteristics suggest the use of triplets of 22 meters long micro 

pillars so as to ensure a reliable three-dimensional fiaming of the eccentricity. 

References 

[l] Sarti P., Sillard P., Vittuari L., 2004. Surveying co-located Space Geodesy techniques for ITRF computation. Journal of Geodesy, in press. 

66 IVS 2003 Annual Report 
Istituto di Woastronomia del CNR, Stazione VLBI di Noto Noto VLBI Station 

I 

Noto Station Activity 

G. Tuccari, C. Stanghellini, S. Buttaccio 

Abstract 

The most important achivements at the Noto station are presented and a status is shown about 

developments and future plans. 

1. Station Activity and Upgrade 

1.1. Antenna 

The new driving system is now fully operative and a few firmware problems shown by the 

system have been fixed. A replacement of the antenna control software is now in a testing stage, it 

will operate within the Field System PC, taking advantage of the her control now possible with 

the new ACU. 

A correction algorithm acting on the primary mirror active surface has been introduced, to 

correct the deformations present in the secondary mirror. This correction improves the efficiency 

for the highest available bands: 22, 43 and 86 GHz. 

1.2. Receivers and Microwave Technology 

The cooled multifeed SXL receiver, even if completed, suffered for a complex vacuum problem, 

that delayed its use. Indeed, the large vacuum box chamber, about 800 mm wide on each side, 

presented a long term leakage due to microscopic fractures on the surface. The problem was 

solved making use of a particular covering material. Now the receiver is going to be reassembled 

and hopefully, it will be in use before the summer. 

A 86 GHz receiver was kindly given to the Noto station on permanent loan by MPI Bonn. 

This primary focus receiver has been adapted to be placed in the antenna with a full remotely 

controlled positioning system. In the first months of 2004, the active surface will be adapted to 

optimize the efficiency at this 3 mm band. 

A new 5 cm receiver is available for VLBI and single dish observations. 

A new VHF-UHF receiver has been built, covering the range 250 - 600 MHz, and 600 - 1200 

MHz. It will be used primarily in EVN observations. 

1.3. Acquisition Terminal and Digital Technology 

The Mark 5A recorder has been installed and tested at 256, 512, 1024 Mbit/s; four packs with 

8 disks are already available and the acquisition of further packs is expected during the year, in 

order to switch as soon as possible to disk only recording. 

A digital baseband converter prototype with wide and narrow band channels is under development. The full project, financed by the EVN, is expected to provide in two years, a fully digital 

system to be used with Mark 5 recorder or enet connection through VSI interface. The first 

experimental tests will be performed during 2004. 

_____~ 

IVS 2003 Annual Report 67 
Noto VLBI Station Istituto di Radioastronomia del CNR, Stazione VLBI di Noto 

2. Geodetic Experiments in Noto during 2003 

During 2003 the Noto radiotelescope participated to the following geodetic experiments: 

EURO67 (25 MAR), EURO68 (06 MAY), CRF18 (lSMAY), T2021 (16 SEP), T2022 (14 OCT), 

CRF24 (8DEC), EURO70 (16DEC). Noto participated also in EURO69 experiment (23SEP) but 

data did not show fringes during correlation. 

68 IVS 2003 Annual Report 
Geodetic Institute, Norwegian Mapping Authority NYAL Ny-Alesund 20 Metre Antenna 

NYAL Ny-hesund 20 Metre Antenna 

Helge Geir Digre 

Abstract 

For the year 2003, the 2Gmeter VLBI antenna at the Geodetic Observatory, Ny-hesund has participated in VLBI experiments at the schdded level, except for the period 12th of June to 19th of June, 

when the Observatory was closed to avoid possible SARS contamination. Maintenance and repair have 

been done. There have been temporary changes in st&. Ny-&Bund's status as an EU Large Scale 

Facility site has not been renewed by EU. 

1. General Information 

The Geodetic Observatory of the Norwegian Mapping Authority at 78.9 N and 11.87 W is 

located in Ny-Alesund, in Kings Bay at the west side of the island Spitsbergen, the biggest island 

in the Svalbard archipelago. In 2003, Ny-Alesund was scheduled for 69 VLBI experiments within 

R4, R1, EURO, VLBA/RDV, RD, T2 and ICRF. In addition to the 20-meter VLBI antenna, 

the observatory has two GPS antennas in the IGS system and a Super Conducting Gravimeter is 

installed on the site. On the site, there is also a CHAMP GPS and a PRARE installation. The 

LaCoste-Romberg has been removed from Ny-hesund. The place Ny-Alesund was an EU Large 

Scale Facility from 1997 to 2002. EU did not renew the LSF status for 2003. Ny-Alesund Geodetic 

Observatory was closed down from 12th of June to 19th of June. The director of Kings Bay had 

invited Chinese visitors from Beijing, who arrived in Ny-Alesund before the 10 days incubation 

period for SARS was through. There has been a change of director in Kings Bay this summer, so 

it is very unlikely that something like this happens again under the new director. 

2. Component Description 

The antenna is intended for geodetic use, and is designed for receiving in S- and X- band. 

The equipment was all Mark 4 until late in the autumn, when it was upgraded with a Mark 5A 

unit - Stat ion configuration file:ftp: / /ivscc.gsfc.nasa.gov /pub/config/ns/nyales.config. Ny-hsund 

is located so far north that it has daytime aurora in winter, and this location of the antenna makes 

it possible to receive over the North Pole. (In 1998, Ny-Alesund was the only antenna that could 

receive signals from the Mars Global Surveyor for 24 hours.) 

3. staff 

The head of the division needed Vidar Eggimann at the main office in Hsnefoss for the rotation 

period from July until November. As replacement, Kari Buset and Tom Pettersen worked about 

one month each on the Observatory during this Pmonth rotation period. David Holland went on 

sick leave at the end of his first period and is still on sick leave. To be able to do the scheduled 

experiments in the rotation period starting the 1st of November, Leif Morten "hgen stayed a bit 

longer in November, and Svein Rekkedal came up for a week in mid-December. 

IVS 2003 Annual Report 69 
NYAL Ny-Alesund 20 Metre Antenna Geodetic Institute, Norwegian Mapping Authority 

Hmefoss: Section manager: 

Station responsible, H~nefoss: 

Ny- Alesund: Station commander: 

Figure 1. Ny-Alesund 20 meter antenna 

Rune I. Hanssen 

Svein Rekkedal 

Leif Morten Tangen / 

Engineers: 

Helge Digre 

Vidar Eggimann / 

David Holland 

Rotation group: Kari Buset (07.2003) 

Tom Pettersen (09.2003) 

4. Current Status and Activities 

Ny-Wlesund has participated in VLBI experiments at the scheduled level, except for the period 

12th of June to 19th of June, when the Observatory was closed to avoid possible SARS contamination. Because of this, Ny-Wlesund did not participate in 4 experiments, while the 5th was moved 

until later in the year. There have been some problems with inert gases, causing the cold head 

failure. The transport time for the replacement cold head has caused that experiments have been 

run with warm receiver. Ny-Alesund’s status as an EU Large Scale Facility site has not been 

70 IVS 2003 Annual Report 
Geodetic Institute, Norwegian Mapping Authority NYAL Ny-Alesund 20 Metre Antenna 

, 

renewed by EU, so there have been no LSF funded scientists visiting the site in 2003. The temp@ 

rary installed (1996) LaCosteRomberg gravimeter has been removed from the bunker where it was 

mounted, and has been returned to the main office in Hnefoss. The Super Conducting Gravimeter 

placed on the same fundament as IGS-GPS NYA1, has been running without any problems. This 

year, PRARE has been more and more unstable and work consuming. From this spring, weekly 

rebooting has been necessary to keep it running. At the end of the year, it would not run at all any 

more. The back up fiom Germany has been very limited since this summer. The "cherry-picker" 

has got new hydraulic hoses all over, so hopefully, it can be recertified next year. Its hydraulic 

pump is electrically driven. In winter, it is much quicker to use then the diesel driven alternative. 

Ny-&sund has bought and installed Mark 5A. After successfully running one experiment 

recording on tape and using Mark 5 in "piggyback-mode", Ny-Alesund is running Mark 5A on all 

experiments except the ones correlated at Socorro. The Mark 5 system has been fully tested and 

is proved able to record with the highest possible data rate. 

The 5-year contract for lease of ground and community services with Kings Bay AS has been 

renewed. The Ministry of Environment funds the Norwegian Mapping Authority (NMA). For 2004, 

there will be cutbacks again. As a part of the process of reducing costs, one of the suggestions 

from NMA was to temporary close down the Geodetic Observatory for an undecided period of 

time, something NMA meant should be easy to do because all employees are on time limited 

contracts. The Ministry of Environment did not accept any close down, so as far as known today, 

the Geodetic Observatory in Ny-Alesund will be running in 2004. 

5. F'uturePlans 

Ny-Alesund will continue to participate in the experiments the antenna is scheduled for, and 

will try to make it possible to increase the number of yearly experiments. The SCG has to be 

refilled with liquid Helium each year, and the lift has to be recertified every year. Hopefully it 

will be possible to have the "cherry-picker" recertified. The Maser is up for the bi-annual service 

check in 2004. Also, it is 2 years since the inner and outer reference systems were checked, so this 

should also be done again in 2004. 

Ny-Alesund reduced the number of experiments from 2002 to 2003. The main reason for this 

was all the problems and the consequences of the problems in 2002. From the middle of November 

to the end of January, Ny-Alesund has the Polar Night and is without any daylight. In 2002, 

January was one of the months that year with most experiments. With trouble during the Polar 

Night, everybody became really aware of the fact that the Observatory is located at almost 79"N. 

What was learned the hivd way then was that breakdowns in winter ought to be avoided, as it is 

difficult to do repair work outdoors during the Polar Night. 

This resulted in the following conclusions: Continue the work on improving the maintenance 

and repair procedures, aiming for achieving only planned downtime. 'Iky to get or build "Module 

based" replacement "bottleneck" sections to reduce downtime. On the location there ought to be 

spare modules containing known critical parts, so the whole module could be taken out for repair, 

while the spare is mounted. Then the module with the defective part should be repaired, serviced 

and tuned indoors in the workshop while the antenna is up and ready again after a short stop 

because the spare module is installed. Critical spare parts should be located in Ny-Alesund to 

avoid downtime and extra repair time caused by transportation time. 

IVS 2003 Annual Report 71 
German Antarctic Receiving Station (GARS) O’Higgins BKG - Wettzell 

German Antarctic Receiving Station (GARS) O’Higgins 

Wolfgang Schlii ter, Christian Plotz, Walter Schwarz, Reiner Wojdziak 

Abstract 

In 2003 the German Antarctic Receiving Station (GARS) in O’Higgins contributed to the IVS 

observing program by dedicated obervation sessions. Mark 5 system has been integrated. Steps have 

been undertaken to conduct remote control operations in the next future. 

1. General Information 

The German Antarctic Receiving Station is jointly operated by the Federal Office of Cartography and Geodesy (BKG), the German Aerospace Center (DLR) and the Institute for Antarctic 

Research Chile (INACH). 

The 9m radiotelescope at O’Higgins is used for geodetic VLBI and for remote sensing purposes. 

Access to the station is organized only campaign-wise during the Antarctic spring and summer 

from November to March. DLR and BKG jointly send engineers and operators for the campaign 

together with a team which maintains the infrastructure such as the provision of power etc: Special 

flights with small Twin Otter aircrafts were organized by INACH in close collaboration with the 

Chilean Army, Navy and Airforce in order to transport the staff, the technical material and also 

the food for the entire campaign from Punta Arenas via Island F’rey to the station O’Higgins on the 

Antarctic Pensinsula. Conditions and time schedule are unpredictable and require a lot of security 

precautions. Arrival time and departure time is strongly dependent on the weather conditions and 

the general logistics. 

After the long Antarctic winter usually the equipment has to be initialised and damages have 

to be identified and repaired. Shipping of spare parts or upgrade material from Germany needs 

careful preparation in advance, but nevertheless the arrival of material in O’Higgins is mostly 

delayed. The station is ready for operation usually just at the last minute before a session is 

planned to start. This requires flexibility not only from the staff but also from those colleagues 

who prepare the schedule and from the staff of the collaborating stations. 

Beside the 9m radiotelescope for VLBI, the site has: 

two GPS receivers, a TURBO Rogue (OHIG), which has a long and stable history and one 

Ashtech 218 receiver, capable for GPS and GLONASS tracking. The Ashtech will be replaced 

by a JAVAD receiver during the summer campaign 2004. 

a PRARE station for the ERS2 tracking, which unfortunately failed due to lack of spare 

parts, in particular due to cable problems. The cable could not be repaired successfully nor 

replaced during the October-December campaign 2003. 

a tide gauge, which has operated several years with some interruptions caused by destroyed 

cables from ice scratching on the rocks, 

a meteorological station providing pressure, temperature and humidity and wind information, 

as long as the extreme conditions outside did not disturb the sensors. 

For the provision of time and frequency, a H-Maser, an atomic Cs-clock, a GPS time receiver 

and a Total Accurate Clock (TAC) are employed. 

72 IVS 2003 Annual Report 
BKG - Wettzell German Antarctic Receiving Station (GARS) O’Hi-s 

Figure 1. GARS O’Higgins 

The 9m radiotelescope is designed for dual purposes: for performing geodetic VLBI and for 

receiving the remote sensing data from ERS 2. JEW and ENVISAT. Different antenna tracking 

modes and different receivers have to be activated dependent on the application. 

2. Technical Staff 

The staff members for operating, maintaining and improving the GARS VLBI component and 

the geodetic devices are summarized in the table 1. 

3. Observations in 2003 

During the Antarctic summer campaign (January/February 2003) and during the Antarctic 

spring campaign (November-December 2003) GARS participated in the following sessions of the 

IVS observing program: 

0 5 sessions during the period January - February (OHIG 23, OHIG24, OHIG25, T2013 and 

T2014) 

0 5 sessions during the period November- December (OHIG26, OHIG27, O’HIG 28, T2023 and 

T2024), 

0 the Vienna Students Project, which was carried out November 27, 2003. 

IVS 2003 Annual Report 73 
German Antarctic Receiving Station (GARS) O’Higgins BKG - Wettzell 

Name Affiliation Function 

Christian Plotz BKG/FESG electronic engineer 

Reiner Wojdiak BKG software engineer 

Walter Schwarz BKG electronic engineer 

Gerhard Kronschnabl BKG electronic engineer 

Due to logistic requirements the observers were forced to leave O’Higgins one week earlier in 

December than planned, right after the last VLBI session. The tapes were packed in a container 

which should be shipped from O’Higgins to Punta Arenas immediately after they left. Unfortunately problems to load the container onto a Navy ship caused a delay of shipping the tapes from 

O’Higgins to Punta Arenas, from where they usually were sent via courier to Wettzell. 

Working for 

O’Higgins (responsible), RTW 

O’Higgins, Data Center Leipzig 

RTW, O’Higgins 

RTW, O’Higgins (partly) 

4. Maintenance 

The extreme conditions in the Antarctic requires maintenance and repair of the GARS telescope 

and of the infrastructure. We have to consider the effect of corrosion; problems with connectors 

and capacitors need to be detected; H-Maser has to set up into operation mode; antenna, S/Xband receiver and the data acquisition system has to set up properly. Conditions outside the 

containers are sometimes very extreme due to the temperature and in particular the speed of 

wind, which reached 160 km/h in December 2003. Up to 250 km/h has been observed during 

previous campaigns. 

Those components which were damaged during the previous campaign usually have to be 

replaced. During this period the device to measure the speed of wind was completely replaced. 

5. Technical Improvements 

The transition from the Mark IV to the Mark 5A has been successfully performed. Two Mark 

5A system were available. Both have been prepared for use in Antarctica ahead of time at the 

Fundamentalstation Wettzell, in order not to be faced with severe problems in O’Higgins. One 

system has been shipped to GARS and is already installed. The second system still remains in 

Wettzell for further development. 

A new computer has been prepared and modified to implement the new Field System version. 

Due to interface problems with a board the Field System and the new PC could not be finally 

integrated in GARS. The problem will be solved by a replacement of the board during the campaign 

at the beginning of 2004. 

For the planned remote control of GARS, more power and a more reliable power system is 

required. A new power generator including UPS is on the way to O’Higgins. The system will 

arrive in O’Higgins in February 2004 and will be set up also in the first campaign 2004. 

All computers for operating the geodetic devices and all servers need a replacement with the 

new PC generation, as they were worn out and caused failures. An Internet link via satellite to 

Santiago with 128 kbps has been established. The link allows regular data transfers and telephone 

communication. The link will be the basis for the remote control. 

74 IVS 2003 Annual Report 
BKG - Wettzell German Antarctic Receiving Station (GARS) O’Higgins 

Figure 2. View fiom the telescope to the Ashtech GPS antenna and to the radome for the Turbo Rogue 

antenna. 

6. Upgrade Plans for 2004 

During 2004 it is planned to replace the Field System computer, to test the Mark 5, to replace 

the worn out power station by a stronger one which will be capable to provide enough power 

during unmanned periods. All these steps are required for the establishment of remote control 

capabilities, which will be prepared and tested for geodetic VLBI as well as for the acquisition of 

remote sensing data in 2004. 

Some restoration work will be done, in order to maintain the antenna as corrosion has to be 

prevented. 

I 1 IVS 2003 Annual Report 75 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO) 

The IVS Network Station Onsala Space Observatory 

Riidiger Haas, and Gunnar Elgered 

Abstract 

We summarize briefly the status of the Onsala Space Observatory in its function as an IVS Network 

Station. The activities during the year 2003, the current status, and future plans are described. 

1. Overview 

The IVS Network Station at the Onsala Space Observatory (OSO) has been described in earlier 

IVS annual reports, e.g. [l], [2] [3] [4]. 

During 2003 a number of maintenance and upgrade activities were performed at Onsala. The 

Russian Kvarz maser was serviced, amplifiers of the telescope azimuth encoders were exchanged, 

the VLBI system was upgraded to Mark 5A, and the observatory was connected by a 1 Gbit/s 

optical fibre link to the Swedish Internet backbone. 

2. Staff Associated with the IVS Network Station at Onsala 

The staff associated with the IVS Network Station at Onsala remained mainly the same as 

reported earlier, e.g. in [l]. However, Lubomir Gradinarsky finished his Ph.D. and left the observatory, while two new Ph.D. students, Camilla Granstrom and Tobias Nilsson, started to work at 

the observatory during 2003. 

Table 1. Staff associated with the IVS Network Station at Onsala. All e-mail addresses end with 

@oso.chalmers.se, the complete telephone numbers start with the prefix +46-31-772. 

Function Name e-mail prefix telephone extension 

Responsible P.1.s Gunnar Elgered kge 5565 

Riidiger Haas haas 5530 

Ph.D. students involved Sten Bergstrand sten 

in VLBI observations Camilla Granstrom Camilla 

Martin Lidberg lidberg 

Tobias Nilsson tobias 

Borys Stoew boris 

5566 

5566 

5578 

5575 

5575 

Field system responsibles Biorn Nilsson biorn 5557 

Michael Lindqvist michael 5508 

VLBI equipment responsibles Karl-.&ke Johansson kaj 

Leif Helldner helldner 

5571 

5576 

VLBI operator Roger Hammargren roger 5551 

Telescope scientists Per Bergman bergman 5552 

Lars Lundahl lundahl 5559 

76 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onda Space Observatory (OSO) 

3. Geodetic VLBI Observations During 2003 

During 2003 the observatory has been involved in the four regular VLBI-experiment series 

EUROPE, IVS-R1, IVS-T2, and RDV. In total OS0 was scheduled to participate in 18 geodetic 

VLBI experiments during 2003 (see Table 2). 

Exper. 

RDV-37 

R4062 

EURO-67 

EURO-68 

RDV-38 

RDV-39 

RDV-40 

R4082 

R4083 

Table 2. Geodetic VLBI experiments at the Onsala Space Observatory during 2003. 

Date 

03.12 

03.13 

03.25 

05.06 

05.07 

06.18 

07.09 

07.31 

08.07 

Remarks (problems) 

0.k. 

0.k. 

o.k., encoder problems 

o.k., S-bad RFI 

o.k., S-bad RFI 

o.k., S-bad RFI 

o.k., S-band RFI 

0.k. 

0.k. 

Exper. Date Remarks (problems) 

R4-084 08.14 0.k. 

RDV-41 09.17 o.k., RFI in Channel 4 X-band 

EURO-69 09.23 o.k., first Mark 5A experiment! 

T2-022 10.14 o.k., second Mark 5A experiment 

R4093 10.16 o.k., encoder problems 

EURO-70 12.16 not correlated yet 

RDV-42 12.17 not correlated yet, encoder problems 

T2-020 08.12 0.k. 

T2-021 09.16 0.k. 

Most of the experiments were observed without problems. However, during some of them we 

unfortunately had technical problems with the telescope’s azimuth encoders that caused loss of 

observational data. In EURO-68 we lost the first 9 scans and later during the experiment nearly 

2 hours. During R4093 about 45 minutes of observations were lost, and during R.DV42 two hours 

of observations were lost due to the encoder problems. 

-io interference in S-band due to UMTS mobile telephone signals was a disturbing factor in 

2003 causing disturbing peaks in the band-pass. Many correlation reports mentioned explicitely 

the radio interference. Also radio interference in X-band was reported for RDV-41. 

The two first experiments recorded with the new Mark 5A system at Onsala were EURO-69 

and T2-022. Both experiments were correlated successfully. 

4. Maintenance and Upgrade of the Onsala VLBI System 

During 2003 the VLBI equipment at Onsala was maintained and upgraded, see Table 3 for an 

overview. The highlights are the installation of a Mark 5A unit and the connection to the Swedish 

Internet backbone by an optical fibre link with 1 Gbit/s capacity. 

The Mark 5A unit was installed at the observatory in August. After thorough testing of the 

equipment the first VLBI experiment with Mark 5A was EURO-69 recorded on September 23. 

The data were correlated succesfully at the Bonn correlator. In December 2003 five Mark 5A units 

were assembled at the observatory and are now dedicated to the IVS disk pool. These Mark 5A 

units are equipped with 8 disks of 160 Gigabyte each. 

In November the Mark 5A unit was connected to the Swedish internet backbone with an optical 

fibre link of a capacity of up to 1 Gbit/s. The Mark 5A unit had to be upgraded to be able to 

handle this data rate. First tests sending data have been perfomed. 

The calibration of the Onsala pressure sensor using a reference barometer provided on a 

long term loan by the Swediih Meteorological and Hydrological Institute (SMHI) was continued throughout the year 2003. The largest offset observed between the two sensors was 0.5 hPa 

IVS 2003 Annual Report 77 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO) 

Table 3. Maintenance and upgrade work of the Onsala VLBI system during 2003. 

February 

April 

August 

November 

November 

December 

Maintenance of Onsala’s Kvarz maser and exchange of the disociator. 

Installation of a new temperature and humidity sensor at the NASA weather station 

and installation of new cables. 

Installation and tests of Mark 5A equipment. 

Installation of two new amplifiers for the telescope’s azimuth encoders. 

Connection of the Mark5 unit to the Swedish internet backbone with an optical 

fibre link of up to 1 Gbit/s capacity. 

Maintenance of all video converter filter cards and checks of offset levels and gains. 

5. Telescope Stability, Reference Point Determination, and Local Tie 

We continued to monitor the vertical changes of the telescope tower by an invar monitoring 

system [6], see Figure 1. We fitted a simple model to express the relative vertical height changes 

measured with the invar rod as a function of the mean value of the temperatures measured with 16 

temperature sensors located at 4 different levels and 4 different directions in the concrete foundation 

of the telescope. The empirically determined expansion coefficient for the concrete foundation of 

the telescope is 9.6 . (l/OC). Here we corrected for an expansion of the invar 

rod using the theoretical expansion coefficient of invar which is 1.5 - (l/OC). The rms of the 

model fit is 0.056 mm. The empirically determined expansion coefficient is slightly smaller than 

the theoretical one for dry concrete which is 12 - lop6. One reason might be that the mean value 

calculated from all temperature sensors does not provide the effective temperature of the concrete. 

f 0.2 - 

I I I I I I I ’ -20 

1996 1997 1998 1999 2000 200 1 2002 2003 2004 -2‘ 

Figure 1. Lower blue curve, left scale: relative vertical height dh in (mm) of the OS0 telescope tower. 

Upper red curve, right scale: mean temperature T in (”) C of the concrete foundation of the telescope. 

The campaign based GPS measurements using an antenna mounted on top of the VLBI telescope [7] have also been continued. 

The classical geodetic measurements performed in the spring and the early summer 2002 at 

the observatory were further analysed [SI. Several geometric properties of the telescope were 

determined: The divergence of the telescope’s azimuth axis with respect to the local vertical was 

found to be to 13” f 6”. A non-orthogonality of the telescope’s azimuth and elevation axis on the 

order of 40” f 8 ” was detected. Furthermore, an axis offset of 6 mm f 0.4 mm was determined. 

78 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO) 

The local tie between the TVS and the IGS reference points at the observatory was determined in 

the local network. Additional GPS observations performed in the local network at the observatory 

allowed us to transform this local tie also into a global reference system. The new local tie 

information was submitted together with its complete covariance information to the International 

Earth Rotation Service (EM). This information is also available from us on request. 

6. Outlook 

The Onsala Space Observatory will continue to be an IVS Network Station and to participate 

in the TVS observation series. For the year 2004 a total of 22 experiments in the series EUROPE, 

RDV, IVSR and IVS-T are planned. 

The Onsala Mark 5A system is now connected to the Swedish Internet backbone by a 1 Gbit/s 

optical fibre link and we plan to participate in international e-VLBI activities. 

The monitoring of the relevant system parameters will be continued in order to detect possible 

error sources as early as possible and to maintain a high quality of the observation data. The 

stability of the telescope, its vertical height changes and the local tie to other monuments will be 

monitored also in the future. 

References 

[l] Haas, R. Elgered, G. and scheme&, H.-G.: On& Space Observatory - IVS Network Station. In: N. R Vandenberg (4.): ZVS 1999 Ann& Report, NASA/TP-l999-209243, 90-93, 2000. 

[2] Haas, R., Elgered, G., Bergstrand, S., Gradin-, L., Stoew, B., and Johansson, K.-A.: The IVS Network 

Station Onsala Space Observatory. In: N. R. Vandenberg and K. D. Baver (Eds.): IVS 2000 Annual Report, 

(31 Haas, R., Johansson, K.-A., Elgered, G., Bergstrand, S., Gradinarsky, L., Stoew, B., Bouma, H., and Lidberg, 

M.: The IVS Network Station Onsala Space Observatory. In: N. R. Vandenberg and K. D. Baver (Eds.): ZVS 

2001 Annual Report, NASA/TP-2002-210001, 108-111, 2002. 

[4] Haas, R., Johansson, K.-A., Elgered, G., Bergstrand, S., Gradinarsky, L., Stoew, B., Bouma, H., and Lidberg, 

M.: The IVS Network Station Onsala Space Observatory. In: N. R. Vandenberg and K. D. Baver (Eds.): ZVS 

2002 Annual Report, NASA/TP-200%211619, 136-139, 2003. 

[5] Elgered, G., and Haas, R.: The Geodetic VLBI Network Station at the Onsala Space Observatory - Activities 

During 2002. In: W. schwegmann and V. Thorandt (Eds.): Pm. of the 16th Working Meeting on Eumpn 

VLBZ for Geodesy and Astmmetry, Bundesamt fiir Kartographie und Geodiisie, 6146, 2003. 

[6] Elgered, G., and Haas, R.: Geodetic Very-Long-Baseline Interferometry at the Onsala Space Observatory 1997- 

1998. In: W. Schliiter and H. Hase (Eds.): Pm. of the 13th Working Meeting on Eumpean VLBZ for Geodesy 

and Astrometry, 6@64,1999. 

[7] Bergstrand, S., R. Haas, and Johansmn, J. M.: A new GPSVLBI tie at the Onsala Space Observatory. In: 

N. R. Vandenberg and K. D. Baver (Eds.): IVS 2000 General Meeting Proceedings, NASA/CP-2000-209893, 

[8] Eschelbach, C., and Haas, R.: The IVS-Reference Point at Onsala - High End Solution for a Real 3D 

Determination? In: W. Schwegmann and V. Thorandt (Eds.): Pmc. of the 16th Working Meeting on European 

VLBI for Geodesy and Astrometry, Bundesamt fiir Kartographie und Geodtisie, 109-118, 2003. 

NASA/TP-2001-209979, 113-116, 2001. 

128-132, 2000. 

IVS 2003 Annual Report 79 
Sheshan VLBI Station Shanghai Astronomical Observatory, CAS 

Sheshan VLBI Station Report for 2003 

Xiaoyu Hong, Wenren Wei, Shiguang Liang, Xinyong Huang 

Abstract 

The Sheshan 25-meter radio telescope is an alt-az antenna run by Shanghai Astronomical Observatory (SHAO), Chinese Academy of Sciences (CAS). It is one of the five main astronomical facilities of 

Chinese National Astronomical Observatories. The VLBI station is a member of the EVN, IVS, and 

APT. Sheshan station also participated in a large mount VSOP survey observation in the period from 

1997 to 2003. We give a short report the current status and future plans of Sheshan VLBI station of 

Shanghai Astronomical Observatory as an IVS Network Station. 

1. Introduction 

The telescope is located about 30 km west of Shanghai. Station is located at longitude: 121’ 

11’ 59” E, latitude: 31’ 05’ 57” N, and height 5 meters above the sea level (ground). 

The radio telescope started its operation in 1987. It is one of the five main astronomical 

facilities of Chinese National Astronomical Observatories. The VLBI station is a member of the 

EVN, APT and IVS. There is a two-station Mark IV data processor and an analysis center of 

IERS of various space geodetic observations in Shanghai Astronomical Observatory. 

Sheshan station participates into the EVN session for astrophysics, IVS session for the geodetic 

purpose, and VSOP survey program. 

2. Facilities 

2.1. Antenna 

Diameter : 25 meters 

Antenna type: Kashegelun beam waveguide 

Seat-rack type: Azimuth-pitching ring 

Main surface precision: 0.65 mm (rms) 

Point precision: 20” (rms) 

Rolling range: Azimuth : -86’ - 425’; Elevation: 5’ - 88’ 

Maximum rolling speed: Azimuth : 0.55’/sec; Elevation: 0.28’/sec 

The quick frequency changing system has been built. Since the L band feed is located at main 

focus while the other feeds are located in second focus, the switch frequency system does not 

include L band. We can change the observed frequency among 3.6/13 cm, 6 cm and 1.3 cm in 5 

minutes. We still need 30 minutes from L band to the others. 

The antenna surface adjustment has been done before September of 2003. The efficiencies at 

short wavelengths have been improved. 

The efficiency at 22 GHz has not been measured carefully yet. We do not have the parameters 

at this moment. 

80 IVS 2003 Annual Report 
Shanghai Astronomical Observatory, CAS Sheshan VLBI Station 

Band 

(4 

(1) 

18 

13 

6 

3.6 

1.3 

2.2. Receiver 

Bandwidth Efficiency Type Tsystem 

(MJW (%) (K) 

(2) (3) (4) (5) 

1620-1680 40 Room Temperature - 100 

2150-2350 45 Room Temperature - 100 

8200-9000 50 Cryogenic N 50 

22100-22600 -20 Crvogenic -110 

4700-5100 58 cryogenic 4550 

Five bands for VLBI observations are available at Sheshan VLBI station: L band (18cm), C 

band (6cm), K band (1.3cm), and S/X band (13/3.6cm). The parameters of the receivers are 

listed in Table 1. Column 1 gives the observation band. The frequency range is listed in column 2, 

followed by the efficiency of each band in column 3. The receiver type, system temperature, and 

polarization model are listed in columns 4, 5 and 6, respectively. 

The L, C, and K bands are used for astrophysics and S/X double frequencies are used for 

geodesy. X band is also used for astrophysical observations sometimes. 

A new C-band receiver with double polarization will be available in the second half of 2004. 

Polarization 

(6) 

LCP & RCP 

RCP 

LCP 

RCP 

RCP & LCP 

2.3. Recording System 

VLBA, Mark IV and S2 recording systems are available now at Sheshan VLBI station. Mark 

IV upgrade of Sheshan station has completed in 2000. Two head stacks recording system has 

been tested successfully and good fringes have been found to Sheshan station, both head-stacks 

successfully. The performance of the observing system of Shanghai station has been more advanced 

over the last few years. 

The Field System has been upgraded to 9.5.17 version and it works well for Sheshan station in 

the second half of 2002. The Mark IV recording system works well for EVN and IVS observations, 

and S2 recording system work well for VSOP observation. Two head stacks recording system has 

been tested successfully and good fringes have been found to Sheshan station. 

We are purchasing a Mark 5A system for Sheshan station. It will be delivered to Shghai at 

the beginning of 2004. 

3. Personnel 

There are some changes of the staff at Sheshan station. The main staff members at Sheshan 

Prof. Liang Shiguang retired in the Nov. 2003. He is still employed to work for our station 

VLBI Station are listed in following Table 2. 

after he retired. 

IVS 2003 Annual Report 81 
Sheshan VLBI Station Shanghai Astronomical Observatory, CAS 

Table 2 - The main staff in Sheshan VLBI Station 

4. Current Status & Activities and Future Plans 

A new Hydrogen Maser Clock has been ordered from Datum for Sheshan VLBI station. The 

Since the antenna control system is not quite stable now, we plan to upgrade it in 2004. 

export license has been approved by USA. We expect to have it in 2004. 

82 IVS 2003 Annual Report 
Lab of Radio Astronomy of crimean Astrophysical Obsavatory Sieiz Station 

“Simeiz-Katsively” Geodynamic Area: Results of the Geodetic 

VLBI Observing Program and Variability of the Black Sea Level 

A. Volvach, Ju. Sokolova, 0. Shabalina 

Abstract 

This rep& givg an overview about the geodetic VLBI activities at the Simeiz station. It also 

summarizes the seasonal and long-term variability of the Black Sea level near Yalta and Katsively. 

1. Measurements of Motion of Simeiz Station Using VLBI 

The different analysis groups use different VLBI software for their investigations. Estimates of 

the horizontal velocity of the radioastronomical station Simeiz were obtained using VLBI observations carried out under geodynamics programs during the years 19942000 using CALC/SOLVE 

for data analysis (Petrov et al., 2001). 

We continue it and the estimations of the horizontal and the vertical velocity of Simeiz station 

were obtained during the years 19942002. To analyse the time series of positions of the Simeiz 

VLBI site 3 million measurements of group delay fiom 1983 to 2003 have been processed using 

the Occam5-1 software at Saint-Petersburg NS Analysis Center. The station rates have been 

estimated by weighted least squares (LSQ) method using a linear model. Figures 1, 2, 3 show the 

time series of topocentric coordinates of Simeiz. 

2. The Black Sea Level 

The 22-m radiotelescope RT-22 is located 80 m from the edge of the Black Sea. The geodynamics areas “Simeiz-Katsively” consists of two satellite laser ranging stations, a permanent GPS 

receiver, a sea level gauge and the radiotelscope RT-22 (Nesterov & Volvach, 2002). All these 

components are located within 3 km. Yalta level gauge is located near Yalta 20 km east of RT-22. 

Measurement of Yalta and Katsively level of Black Sea are plotted in Figure 4. 

Height of a level is given in centimeters concerning uniform zero for posts of the Black Sea, 

which is located 500 cm below the zero Kronshtadt tide-gauge. High factor of correlation 0.964 

testifies to synchronous change of levels. The level varies insignificantly from January till March. 

Then it begins prompt growth till May. Then the growth is slowed down and in June there comes 

a maximum. After July there is a fast fall up to the minimal size observable in October. born 

October till November the seasonal level varies little. In the period from November till December 

there is fast growth which is slowed down in the period December - January. The long-term 

variability of average annual value of sea level for Yalta and Katsively is shown in Figure 5. 

Until 1999 the growth in change of sea level was observed. Then in 2000 the growth was slowed 

down and the recession began. 

3. FuturePlans 

The VLBI activities in 2004 at “Simeiz-Katsively” area will consist of: (1) carrying out modernization of sites VLBI (Mark5B system), SLR-1 and SLR-2 with the purpose to increase their 

IVS 2003 Annual Report 83 
Simeiz Station Lab of Radio Astronomy of Crimean Astrophysical Observatory 

8.54 

8.52 

8.50 

8.48 z 

c 

Q) 

I 

8.46 

8.44 

8.42 

8.40 

l! 

5.10 

5.05 

5.00 

L 

Q) 

5 4.95 

I 

CRIMEA LATITUDE VELOCITY 

h 

- linear model 

4 1996 1998 2000 2002 2004 

Year 

Figure 1. Crimea latitude velocity. 

CRIMEA LONGITUDE VELOCITY 

4.85 

I - post-fit residuals 

4.80 

1994 1996 1998 2000 2002 2004 

Year 

Figure 2. Crimea longitude velocity. 

84 IVS 2003 Annual Report 
Lab of Radio Astronomy of Crimean Astrophysical Observatory Simeiz Station 

4.66 

4.64 

4.62 

L 4.60 

Q) 

c 

4.58 

s 

4.56 

4.54 

CRIMEA RADIAL VELOCITY 

linear model 

- post-fit residuals 

T 

T 

4.52 

1 994 1 996 1998 2000 2002 2004 

Year 

Figure 3. Crimea radial velocity. 

E 

0 

- 

m 405 485 > 

m 

_I 

465 465 

" Years ,ears 

Figure 4. The Black Sea level near Yalta and Katsively. 

IVS 2003 Annual Report 
Simeiz Station Lab of Radio Astronomy of Crimean Astrophysical Observatory 

-tttttYaI ta 

E 

473 ), 

1992 1994 1996 1998 2000 2002 2004 

Years 

Figure 5. The long-term variability of Black Sea near Yalta and Katsively. 

level of equipment according to the international standards; (2) realization of observations on 

sites VLBI and SLR for maintenance in territory of Crimea the International Terrestrial Reference Frame (ITRF) and high-precision connection (at a level of several millimeters) permanent 

GPS stations of the network to ITRF; (3) creation of the prototype of a system of monitoring of 

geodynamic phenomena of mountain region of Crimea and geotectonics of the Black Sea basin. 

4. Acknowledgment 

VLBI is possible only as a result of the coordinated efforts of many people. Authors would like 

to thank I. Srepka and N. Srepka for maintenance of the receivers at the station, P. Nikitin, A. 

Shevchenko and P. Koseko for their efforts in observations as well as the personnel at other VLBI 

stations and correlators. 

References 

[l] L. Petrov, A. Volvach, N. Nesterov, In: Kinematics and Physics of Celestial Bodies, Vo1.17, N5, P.424- 

436, 2001. 

[2] N. Nesterov, A. Volvach, Geodetic Study at the Simeiz Stations, In: International VLBI Service 

for Geodesy and Astrometry 2000 Annual Report, NASA/TP-2002-210001. N. R. Vandenberg and 

K. D. Baver (eds.), 115-118, 2002. 

[3] Kuklin A.K., Man’kovsky V.I., Sobolev M.V., Shabalina O.A., Seasonal and longOterm variability of 

the Black Sea level near the Criean Southern Coast, In: Ecological safety of coastal and shelf zones 

and complex use of shelf resources, Sevastopol, Ivanov V.A. et all (eds.), 94100, 2001. 

86 IVS 2003 Annual Report 
Institute of Applied Astronomy of Russian Academy of Sciences Svetloe Station 

Svetloe Radio Astronomical Observatory 

Sergey Smolentsev, Ismail Rachimov 

Abstract 

This report provides information about changes in the Svetloe Radio Astronomy Observatory 

(SvRAO) status in period spanning after the last IVS report. The activities during 2003, the current status, and future plans are described. In 2003, after successful installation of a Mark 3A terminal 

in cooperation with NASA, SvRAO started participation in IVS observing program, which is our main 

achievement during last year, and a major milestone for the QUASAR project. 

1. Introduction 

Svetloe Radio Astronomical Observatory (SvRAO) was founded by the Institute of Applied 

Astronomy (IAA) as the first station of Russian VLBI network QUASAR. Sponsoring organization 

of the project is Russian Academy of Sciences. The site is located at the Karelian Neck near Svetloe 

village about 100 km north from St. Petersburg. The basic instruments of the observatory are 

32-m radio telescope EM%-32 and technical systems provided realization of VLBI observations. 

During last years Svetloe observatory regularly participated in various radio astronomy programs including VLBI and RL VLBI observations of quasars, Sun, planets, asteroids using recording terminal S2-RT. In particular, several observing sessions were performed on the baseline 

Svetloe-Zelenchukskaya. 

In 2003, after successful installation of a Mark 3A terminal in cooperation with NASA, on Mar 

6, 2003 SvRAO started participation in IVS observing program, which is our main achievement 

during last year, and a major milestone for the QUASAR project [l]. 

2. Participation in WS Observing Programs 

During 2003 Svetloe IVS station participated in 21 R4, T2 and EURO sessions (Table 1). 

Table 1. List of IVS sessions observed at SvRAO in 2003. 

Month R4 T2 EURO 

March 2 1 

April 2 1 

May 1 1 1 

June 1 

July 2 

August 2 

September 2 1 

October 3 

November 1 

Total 16 3 2 

Four R4 sessions were not correlated in time because of delay in tape delivering due to customs 

problems. Four scheduled experiments were not observed due to BBC upgrade at Signatron (USA), 

IVS 2003 Annual Report 87 
Svetloe Station Institute of Applied Astronomy of Russian Academy of Sciences 

one experiment was not observed due to planned repair of radio telescope, and one experiment 

was cancelled. Totally 16 sessions were correlated and are available for scientific analysis. 

An analysis of the observations performed at the IAA by means of OCCAM software allowed 

us to determine SVETLOE coordinates at the millimeter level of accuracy. It was also shown that 

including Svetloe observatory in the IVS network yields essential improvement of the accuracy of 

determination of the EOP. We processed the same observations using all participating stations 

and excluding SVETLOE from the network. The results of comparison showed a decrease both in 

EOP uncertainty and postfit wrms [2]. 

3. Radio Telescope 

Geodetic control measurements at the radio telescope dish surface were fulfilled (Fig 1). The 

antenna was painted in August 2003. 

Figure 1. Geodetic control of the radio telescope surface. 

The radio telescope is equipped with 5 low-noise cooled receivers with HEMT amplifiers for 

wavelengths 1.35, 3.5, 6.0, 13 and 18/21 cm for observations in the left and right circular polarizations. The parameters of the LCP X band receiver were improved. The latest results of 

88 IVS 2003 Annual Report 
Institute of Applied Astronomy of Russian Academy of Sciences Svetloe Station 

measurements of radio telescope parameters carried out in 2003 are presented in Table 2. 

Table 2. Parameters of the radio telescope RTF-32 at SvRAO. 

Band Pol Frequency range, MHz T‘,,, K Tsys, K SEFD 

X R 81 80-8880 15 40 250 

L 8180-8680 13 38 240 

S R 2150-2500 42 80 600 

4. Collocation with GPS 

A permanent GPS receiver was installed at Svetloe in 1996. Svetloe observatory participated 

in several regional and global geodetic GPS projects, and is an EPN station from 1996, and an 

IGS station from 2003. 

The local geodetic network (LGN) was established at SvMO in 1994 (see IVS 2000 Annual 

Fieport). In 1995-1998 several local surveys were performed at Svetloe. In result, GPS marker is 

tied to the LGN with the accuracy about 2 mm. However, we still cannot provide an accurate 

survey involving the VLBI radio antenna. In December 2003 a leveling sessions was carried out to 

check LGN markers stability. 

5. Outlook 

Our plans for the coming year are the following. 

0 Recording terminal Mark 5A will be put into operation. 

0 Installation of Canadian S2 DAS in cooperation with NRCan and start in the IVS E3 ob0 Participation in 39 IVS R4, T2, EURO and E3 observing sessions. 

0 Geodetic survey for accurate tie between the radio telescope and the SVTL GPS marker. 

serving program. 

References 

Finkelstein, A. M., A. V. Ipatov, S. G. Smolentsev, V. G. Grachev, I. A. Rahimov, Z. M. Malkin, 2003: 

Highly Accurate Determination of the Coordinates and the Earth’s Rotation Parameters Involving the 

Svetloe VLBI Observatory. Astronomy Letters, 2003, 29, No 10,667473. 

Finkelstein, A., V. Gratchev, A. Ipatov, Z. Mallcin, I. Rahimov, E. Skurikhina, S. Smolentsev Some 

results of the first year of participation of the Svetloe observatory in IVS observing programs. To be 

presented at the Third IVS General Meeting Abstracts, Ottawa, Canada, Feb 9-11, 2004. 

IVS 2003 Annual Report 89 
TIGO Bundesamt fiir Kartographie und Geodtisie 

Geodetic Observatory TIGO in Concepci6n 

Hayo Hase, Armin Boer, Stefan Riepl, Sergio Sobarzo, Cristobal Jara, Roberto Aedo, 

Gonzalo Remedi, Marcus Moreno, Matias Sanchez, Gonzalo Hermosilla 

Abstract 

During TIGO’s second year of operation in Concepcih, TIGO performed 106 24h VLBI observations and is hence one of the most scheduled IVS sites. The operational load is carried out by a 

relatively young team of Chilean students. Activities of the VLBI group at TIGO during 2003 and an 

outlook for 2004 are given. 

1. General Information 

One year after the arrival of TIGO in Chile in 2002, on January 15, 2003, the Geodetic Obser0 Intendente Jaime Toha (Representative of the President of Chile in the Eighth Region), 

0 Rector Sergio Lavanchy (Universidad de Concepcih), 

0 Henning Rosen (Representative of German Minister of Interior), 

0 Prof. Dietmar Grunreich (President of Bundesamt fur Kartographie und Geodsie) 

vatory TIGO was officially inaugurated with speeches by 

in the presence of the rectors of the two other partner universities, Hilario Hernandez of Universidad 

del Bio Bio and Fernando Jimenez of Universidad Cat6lica de la Santisima Concepci6n, and the 

Commander in Chief of the Chilean Army, General Cheyre with the director of the Instituto 

Geografico Militar, General Pablo Gran and more than 180 invited guests. 

During 2003 the existing committments of TIGO towards the international services like IVS, 

ILRS, IGS and UT at BIPM had been kept by lots of data from Concepci6n. 

2. Component Description 

The IVS network station TIGOCONC is the VLBI part of the Geodetic Observatory TIGO, 

which was designed to be a fundamental station for geodesy. Hence the VLBI radiotelescope is 

collocated with a SLR telescope (ILRS site), a GPS/Glonass permanent receiver (IGS site) and 

other instruments like water vapour radiometer, superconducting gravity meter, seismometer. 

The atomic clock ensemble of TIGO consists of 2 hydrogen masers, 2 cesium clocks and 3 GPS 

time receivers realizing the Chilean contribution to the Universal Time scale (Circular T, BIPM). 

The technical parameters of the TIGO radiotelescope as published in [l] have not been changed. 

In November 2003 the first Mark 5 observations had been performed. Since then TIGO supports 

TIGO’s spare Mark 4 formatter was given on loan to Hobart, University of Tasmania, in order 

Mark 4 thintape, Mark 5 fixdisk and S2 VHS tape recordings. 

to improve the observation possibilities in the southern hemisphere within the IVS. 

3. StafF 

In 2003 chief engineer Eduardo Carvacho terminated his work at TIGO. As a replacement 

UdeC hired 2 doctorate students of the electrical department of the engineering faculty, Sergio 

90 IVS 2003 Annual Report 
Bundesamt fiir Kartographie und Geo&ie TIGO 

Staff 

Hayo Hase 

Sergio Sobarzo 

Cristobal Jara 

Roberto Aedo 

Gonzalo Remedi 

Marcos Moreno 

Matias Sanchez 

Gonzalo Hermosilla 

any VLBI-operator 

all VLBI-operators 

Figure 1. Geodetic Observatory TIGO: Instruments from left to right: water vapour radiometer, SLR 

Radar, SLR telescope, meteorological sensors, VLBI radiotelescope, local survey monument. 

Function 

head 

chief engineer 

electronic engineer 

electronic engineer 

programmer 

geologist 

geologist 

geologist 

on duty 

Sobarzo and Cristobal Jara. Both of them together with Hayo Hase participated in the IVS-TOW 

2003. The actual TIGO-VLBI group consists of the persons listed in table 1. 

Email 

hayo. hase@ t igo.cl 

sergio.sobarzo@tigo.cl 

crist obal.jara@ t igoxl 

roberto.aedo@tigo.cl 

gonzalo.remedi@tigo.cl 

marcos.moreno@tigo.cl 

matias.sanchez@tigo.cl 

gonzalo. hermosilla@tigo.cl 

vlbi@tigo.cl 

vlbist&@tiRo.cl 

Table 1. TIGO-VLBI support staff in 2003. 

4. Current Status and Activities 

During 2003 TIGO was participating in 106 VLBI experiments (24h) and one 3h experiment 

within a students project of the Technical University of Vienna. The operation of the latter one at 

TIGOCONC was broadcasted via webcams and the internet based video conference system VRVS 

IVS 2003 Annual Report 91 
TIGO Bundesamt fiir Kartographie und Geodkie 

(http://www.vrvs.org) to the classroom at Vienna, from where the students participated. Table 2 

gives an overview about the observed experiment series. 

Name 

RlOxx 

T20xx 

E30xx 

R40xx 

RDVXX 

RDXXX 

OHIGxx 

# of exp. 

51 

2 

11 

26 

5 

10 

6 

Total IVS 

VIExx 

10 - 

106 

r 

101 5 

1 

Table 2. TIGO’s IVS observation statistic. 

Besides ongoing VLBI observations a local site survey was executed in March/April 2003 by 

Rudolf Zernecke (TUM Wettzell), and Rodrigo Miranda (UdeC). This survey tied the VLBI radiotelescope reference points to those of the ILRS site and the IGS site at TIGO. In addition a 

precision levelling was executed to tie TIGO to the Chilean vertical reference system. 

In April 2003 three borehole tiltmeters had been installed at each of the three international 

service platforms: at the radiotelesope fundament, at the laser telescope fundament and inside the 

GPS/GLONASS monument in order to monitor longterm inclinations [2], [3]. 

5. Future Plans 

The VLBI-activities in 2004 will focus on 

0 execution of the IVS observation program for 2004, 

0 participation in the IVS-VLBI2010 working group, 

0 testing the spare Mark 5 unit, 

0 investigations related to eVLBI, 

0 development of a VLBI operators certification program, 

0 the installation of an upgrade for the antenna control unit and programming the Field System 

0 repetition of the local survey. 

In early 2004 a complementary regional GPS network will be installed with four permanent 

GPS receivers, Ashtec 212, for the regional monitoring of the TIGO site stability. The selected 

sites are Dichato, Quellon, Santa Juana, Faro Hualpen and distances to TIGO range from 20-50km. 

At the coastal site of Dichato the GPS monument will be collocated with a tidegauge in order to 

connect TIGO to the mean sealevel. This regional GPS network will allow complementary studies 

of the local ionospheric and water vapour conditions. 

antenna interface (September/October 2004)’ 

92 IVS 2003 Annual Report 
Bundesamt fiir Kartographie und Geohie TIGO 

Figure 2. Logo of TIGO symbolizes a reference point. It consists of a symbolic reference cross indicating 

the classical perpendicular orientation directions as it is used to indicate north-south and east-west. The 

millimetric reference point is located at the intersection of the four directions. The four letters “TIGO” are 

arranged in a circle, which allows the association with a sextant or a telescope tube with counter weights. 

This association is intended - connecting TIGO’s actual mission to the historical achievements of geodesy. 

The used colours are taken from the German and Chilean flags, symbolizing the cooperation within this 

bilateral project. 

References 

[l] Vandenberg, N.R.: International VLBI Service for Geodesy and Astrometry 2000 Annual Report, 

[2] Hase, H., Bkr, A., Riepl, S., Avendaiio, M., Sobarm, S., Aedo, R., bmedi, G., Moreno, M., Sanchez, 

M., Hermosilla, G.: First Results of TIGO Borehole Tiltmeters in Concepci&, in: Proceedings of the 

16th Working Meeting on European VLBI for Geodesy and Astrometry, BKG, 2003 

[3] Avendaiio, M.: Los Incliometros de TIGO, unpublished diploma thesis, Universidad del Bio Bio, 2003 

NASA/TP-1999-209243,1999 

IVS 2003 Annual Report 93 
Tsukuba 32m VLBI Station Geographical Survey Institute, Japan 

Tsukuba 32-m VLBI Station 

Kozin Wada, Shin0 bu Kurihara, Kazuhiro Takashima 

Abstract 

This report summarizes the improvement of devices and observation activities at Tsukuba 32 m 

station. We had 31 international, 11 domestic and 32 Intensive UT1 sessions during this year. We have 

installed the disk-based K-5 recording system connected to the Internet. Also we have started some 

preliminary experiments with a high-speed network, Super-SINET, for realtime observation and mass 

data transfer. For the first stage of future e-VLBI, we plan to use these systems for regular domestic 

experiments in 2004. 

1. General Information 

The Tsukuba 32 m VLBI station (TSUKUB32) is located at “Geographical Survey Institute” 

(GSI) in Tsukuba Science City, a core area of public and private scientific research institutes, about 

50 km northeast of the capital Tokyo. GSI started VLBI experiments in 1981 with a 5 m-mobile 

station. Through the history of experiments, GSI had also operated a 3.8 m-mobile station and the 

Kashima-26 m station. TSUKUB32 has been in operation since 1998. Since then GSI has shifted 

Figure 1. Tskuba 32 m VLBI station and GARNET (GSI VLBI network) 

its aim of experiments from mobile observations toward fixed regular ones. TSUKUB32 has been 

operational as a main dish of GSI with three other permanent stations, Aira, Shintotsukawa and 

Chichijima, performing geodetic VLBI experiments on a regular basis in a variety of international, 

domestic and other scientific experiments (Table 4). The network of the GSI VLBI stations is 

named GARNET @SI Advanced Radiotelescope Network). The main purposes of this network 

are to define the framework of Japan and to monitor the plate motions for the advanced study of 

crustal deformations. For this reason the four fixed stations including TSUKUB32 are placed to 

surround the Japanese mainland (Figure 1). 

94 IVS 2003 Annual Report 
Geographical Survey Institute, Japan Tsukuba 32m VLBI Station 

Latitude (deg) 

Longitude (deg) 

Altitude 

Address 

Table 1. Location and address of Tsukuba 32m VLBI station 

36.1031 N 

140.0887 E 

44.7 m 

Geographical Survey Institute(Kitasat0 1 Tsukuba lbaraki 3050811 JAPAN) 

2. Component Description 

The current configuration of TSUKUB32 is shown in Table 2. In 2003 we have installed the 

K-5 sampliig/recording system in parallel with the K-4 and Mark IV (VLBA). The backend Kseries systems have been developed at Communication Research Laboratory (CRL). In addition, 

we have already realized the remotecontrolled system with K-4 and used it within GARNET. 

The remotecontrolled system is also applied to the K-5 system easily. The combination of the 

remotecontrolled system with K-5 will provide the increase of the number of experiments. Some 

preliminary experiments for the K-5 system were held with ClU and GIFU University. 

Table 2. Configuration of Tsukuba 32m antenna 

-3957408.752 -3957408.779 

3310299.390 

3. Staff 

Table 3 shows the regular operating staff of VLBI group at GSI. Four new staff members have 

joined this year because both regular observations and correlation works have been increased. 

Shigeru Matsuzaka is a member of TVS Directing Board (Networks Representative). Hiromichi 

Tsuji is the supervisor of VLBI group. Yoshihiro Fukusaki is in charge of the analysis of SYOWA 

experiments, although he is not an regular member. Kouhei Miyagawa, former chief of analysis, 

moved from our group in April 2003. 

IVS 2003 Annual Report 95 
Tsukuba 32m VLBI Station Geographical Survey Institute, Japan 

Table 3. Staff working at GSI VLBI group 

Name Posit ion Jobs 

Kazuhiro TAKASHIMA Leader of VLBI group Management 

Takashi TSUTSUMI Collocation chief Collocation, Operation 

Morito MACHIDA Analysis chief Correlation, Operation 

Masayoshi ISHIMOTO Network chief Network, e-VLBI, Operation 

Kozin WADA Operation chief Experiments coordination, Operation 

Shinobu KUFUHARA Operator Analysis, Operation 

4. Current Status and Activities 

Table 4. The regular experiments at Tsukuba 32 m VLBI station in 2003 

Experiment Code Number 

IVS-R R1054,56,60,61,62,66,67,70,73,74,76,77,79,85,86,87,90,100,R4073 19 

IVS-T T2013,2014,2015,2022 4 

VLBA RDV37,38,39,40,41,42 6 

APSG APSG 12,13 2 

JADE JD0301-0311 11 

UT1 K03102-KO3354 32 

Total 74 

As for the regular experiments listed in Table 4, we have added 17 experiments, which were for 

UT1 and JADE experiments with the K-4 system, compared with last year. The number of other 

regular experiments with the Mark IV (VLBA) system has been constant over the past few years. 

A series of the experiments is named JADE (Japanese bnamic Earth observation by VLBI). The 

main purpose of JADE experiment is to monitor the plate motions around Japan periodically once a month. One of the most remarkable results was detection of Tokachioki Earthquake event which occurred on September 26th (Fig 2). The JADE experiments are opened 

to any VLBI stations with the K-4 recording system. As a result, many Japanese VLBI stations, such as GIFU11, TOMAKO11, KASHIM11, KASHIM34, MIZNAO10 and VERAMIZSW 

have participated in JADE experiments. All these results are available on GSI VLBI Web site 

(http: / /vldb.gsi.go.jp/sokuchi/vlbi/sess/index.html) . Totally 32 Intensive UT1 sessions were carried out with the TSUKUB32-WETTZELL baseline 

every Saturday using the K-4 system. The sessions are scheduled as the complement to the 

KOKEE-WETTZELL baseline. Since UT1 session is still vacant on Sunday and Thursday, we will 

try to fill up all days through a week. 

The TSUKUB32 station has been connected to very-high speed optical fiber network (2.4Gbps) 

named Super-SINET managed by National Institute of Informatics (NII). The network is used for 

realtime observation and mass data transfer in VLBI. Though the network is still under construcIn 2003, domestic experiments using GARNET were carried out totally 11 times. 

96 IVS 2003 Annual Report 
Geographical Survey Institute, Japan __. Tsukuba 32m VLBI Station 

Figure 2. Tokachioki Earthquake and the result of JADE experiment 

tion, it has already started to carry out some experiments. Practical scientific experiments had 

been held with the TSUKUB32-USUDA64 (JAM) baseline for the realtime celestial object survey, planned by National Astronomical Observatory of Japan (NAOJ), from January to March. 

Also the real time fringe test had been done successfully with the TSUKUB32-GIFU11 baseline 

on November 11th. 

5. F’uturePlans 

At the beginning of 2004, we are ready to install K-5 systems to other GARNET stations. 

This means that it is the transition period from tapebased to hard disk-based recording system. 

Basically we plan to replace K-4 systems with K-5 to use for regular basis in domestic experiments 

until 2005. In addition, we plan to install software correlator for the K-5 system in Tsukuba 

with the high-speed network. We are also developing the compatibility of Mark 5 and K-5 in 

cooperation with CRL. With this advanced technique, K-5 system can be used in international 

regular experiments in the near future. 

References 

[l] K. Takashima, S. Kurihara: Tsukuba 32m VLBI station, NS 2002 Annual Report, February 2003 

[2] K. Takashima, S. Kurihara, M. Ishihara, K. Nemoto, M. Iwata, K. Shiba, M. Onogaki, and K. 

Kobayashi: Status and Results of GSI Domestic VLBI Networks, Bull. Geograph. Surv. Inst., Vol. 

46, pp.1-9, March 2000 

IVS 2003 Annud Report 97 
Westford Antenna MIT Haystack Observatory 

Westford Antenna 

Michael Poirier 

Abstract 

Technical information is provided about the antenna and VLBI equipment at the Westford site of 

Haystack Observatory, and about changes to the systems since the 2002 IVS Annual Report. 

1. Westford Antenna at Haystack Observatory 

Since 1981 the Westford antenna has been one of the primary geodetic VLBI sites in the world. 

Located -70 km northwest of Boston, Massachusetts, the antenna is part of the MIT Haystack 

Observatory complex. 

Figure 1. The radome of the Westford antenna. 

The Westford antenna was constructed in 1961 as part of the Lincoln Laboratory Project West 

Ford that demonstrated the feasibility of long-distance communication by bouncing radio signals 

off a spacecraft-deployed belt of copper dipoles at an altitude of 3600 km. In 1981 the antenna was 

converted to geodetic use as one of the first two VLBI stations in the National Geodetic Survey 

Project POLARIS. Westford has continued to perform geodetic VLBI observations on a regular 

basis since 1981. Westford has also served as a test bed in the development of new equipment 

and techniques now employed in geodetic VLBI worldwide. Primary funding for geodetic VLBI at 

Westford is provided by the NASA Space Geodesy Program. 

98 IVS 2003 Annual Report 
MIT Haystack Obsenatory Westford Antenna 

Table 1. Location and addresses of Westford antenna. 

71-49" W 

Off Route 40 

Westford, MA 01886-1299 U.S.A. 

I http://urrv.haystack.mit.edu I 

2. Technical Parameters of the Westford Antenna and Equipment 

The technical parameters of the Westford antenna, which is shown in Figure 2, are summarized 

in Table 2. 

Figure 2. P deangle view of Westford antenna inside the radome. The VLBI S/X receiver is located at 

the prime focus. The subreflector in front of the receiver is installed when observing with the TAL receiver 

(see Section 4), which is located at the Cassegrain focus. 

The antenna is enclosed in a 28-meter-diameter, air-inflated radome made of 1.2-mm-thick, 

Teflon-coated fiberglass - see Figure 1. When the radome is wet, system temperatures increase by 

10-20 K at X-band and by a smaller amount at S-band. The major components of the VLBI data 

acquisition system are a Mark 4 electronics rack, a Mark 4 tape drive, which is used for recording 

thin tapes only, a Mark 5A recording system, and a Pentium-class PC running PC Field System 

IVS 2003 Annual Report 99 
Westford Antenna MIT Haystack Observatory 

Table 2. Technical parameters of the Westford antenna for geodetic VLBI. 

~~ ~ 

Parameter 

primary reflector shape 

primary reflector diameter 

primary reflector material 

S/X feed location 

focal length 

antenna mount 

antenna drives 

azimuth range 

elevation range 

azimuth slew speed 

elevation slew meed 

Westford 

symmetric paraboloid 

18.3 meters 

aluminum honeycomb 

primary focus 

5.5 meters 

elevation over azimuth 

electric (DC) motors 

90" - 470" 

4" - 87" 

3" s-l 

2" s-l 

frequency range 

Tsys at zenith 5&55 K 70-75 K 

aperture efficiency 

SEFD at zenith 1400 Jv 1400 Jv 

version 9.6.9. The primary frequency and time standard is the NR-4 hydrogen maser. A CNS Clock 

GPS receiver system provides independent timing information and comparisons between GPS and 

the maser. Westford also hosts the WES2 GPS site of the IGS network. A Dorne-Margolin GPS 

antenna is located on top of a tower -60 meters from the VLBI antenna, and a Turbo Rogue 

receiver acquires the GPS data. A meteorology package provided by the NOAA Forecast Systems 

Laboratory continually logs meteorological data, which are downloaded daily and are available 

from the IGS and cignet archives. 

3. Westford Staff 

The personnel associated with the VLBI program at Westford and their primary responsibilities 

are: 

John Ball pointing system software 

Joe Carter antenna controls 

Ellen Cellini observer 

Brian Corey VLBI technical support 

Glenn Millson observer 

Michael Poirier 

Alan Whitney site director 

site manager; chief observer 

100 IVS 2003 Annual Report 
MIT Haystack Observatory Westford Antenna 

4. Status of the Westford Antenna 

During the period 2003 January 1 - 2003 December 31, Westford participated in a total of 

71 24hour geodetic experiments. Westford participated regularly in the IVSR1, IVSR&D, and 

RD-VLBA series of geodetic experiments, as well as four IVST2 sessions and various fringe tests 

and e-VLBI experiments. 

A Mark 5A recorder was installed at Westford in June 2003, as a replacement for the Mark 5P 

prototype used over the preceding year in occasional engineering tests and e-VLBI experiments. 

The Mark 5A has been used to record all geodetic sessions since June, with the exception of the 

RD-VLBA experiments, which are still recorded on tape. 

There have been no significant equipment failures during this operational period. 

Use of the Westford antenna is shared with the Terrestrial Air Link (TAL) Program operated 

by the MIT Lincoln Laboratory. In this project Westford serves as the receiving end on a 42- 

km-long terrestrial air link designed to study atmospheric effects on the propagation of wideband 

communications signals at 20 GHz. 

5. e-VLBI Development at Westford 

Westford continues to play a key role in the development of e-VLBI. In 2003, a number of 

e-VLBI demonstration experiments were carried out. Among them was a Kashima (Japan) to 

Westford UT1 experiment where data were recorded at Kashima and Westford on the K5 system, 

as well as on the Mark 5A system at Westford. Data were transferred via e-VLBI in both directions, 

with the necessary format conversion hm K5 to Mark 5A format done via software. Correlation 

was done both on a software correlator in Japan and the Mark 4 correlator at Haystack. Data 

from the Haystack correlator were transferred to NASA/GSFC for analysis of the UT1 results. All 

of this was done in less than 22 hours, from data collection to final results! 

6. Outlook 

We anticipate Westford will be able to participate in the 72 24hour geodetic experiments that 

are scheduled for Westford in 2004. More e-VLBI experiments are also planned for 2004. 

IVS 2003 Annual Report 101 
Fundamentalstation Wettzell - 20m Radiotelescope BKG - Wettzell 

Fundamentalstation Wettzell - 20m Radiotelescope 

Wolfgang Schliiter, Richard Kilger 

Abstract 

In 2003 the radiotelescope in Wettzell contributed strongly to the IVS observing program. The 

transition to the Mark 5A system has been completed for routine operation, a 34 Mbps Internet link 

has been installed for first e-VLBI activities. Technical upgrades have been done. 

1. General Information 

The radiotelescope in Wettzell (RTW) is jointly operated by the Bundesamt fur Kartographie 

und Geodhie (BKG) and the Forschungseinrichtung Satellitengeodhie/Technical University of 

Munich (FESG) within the frame of the Forschungsgruppe Satellitengeodhie (FGS). 

At the Fundamentalstation Wettzell (FSW) the 20m Radiotelescope (RTW) for VLBI is collocated with three more geodetic space technique systems: 

0 the Laser ranging system WLRS (Wettzell Laser Ranging System) designed for SLR and 

0 several GPS receivers, integrated in the global IGS, the European GPS, and in the national 

0 a DORIS station on loan from CNES/France. 

At the Wettzell observatory, the first ringlaser, “G” dedicated to the monitoring of the variations in Earth rotation has been developed in close cooperation with the University of CanterburyNew Zealand. The system was established in 1998 to 2001 and is operating since fall 2001. “G” is 

sensitive to monitoring daily variations better than lo-’ relative accuracy. 

LLR, 

GPS network, and for time transfer experiments, 

Additional in situ observations were carried out such as: 

0 gravity observations, employing a super conducting gravity meter 

0 earth quake observations with a seismometer 

0 meteorological observations to monitor pressure, temperature and humidity, rain fall, wind 

speed, wind direction and also 

0 water vapour observations with a radiometer. 

A Time and Frequency system (T&F) is established for the generation of timescales (UTC(1fAG)) 

and for the provision of very precise frequencies needed for VLBI, SLR/LLR and GPS observations, employing Cs-clocks and H-Masers and GPS time receivers. The timescale UTC(1fAG) is 

published in the monthly Bulletin T of the BIPM. 

The 20m radiotelscope (RTW) has been established during the period 1980 to 1983. First 

observations were performed in 1983, routine operation started 1984. Since that time the telescope 

contributed strongly and continuously to many geodetic VLBI measurements. 

102 IVS 2003 Annual Report 
BKG - Wettzell Fundamentalstation Wettzell - 20m Radiotelescope 

Figure 1. View of the FundamentalStation Wettzell 

2. Staff 

The staff of the Fundamentalstation Wettzell consists in total of 35 members for operating, 

maintaining and improving all the devices, and developing new systems. Within the responsibility 

of the Fundamentalstation Wettzell are the TIGO systems, operated in Concepcion-Chile jointly 

with a Chilean partner consortium with 3 experts from Wettzell, and the O’Higgins station, jointly 

operated with the German Space Center (DLR) and the Institute for Antarctic Research Chile 

(INACH). The staff operating the 20m radiotelcope in Wettzell (RTW) is summarized in the table 

1. 

3. Observations in 2003 

The RTW was schedule in 2003 in total for 122 24 hr experiments of the IVS observing program. 

In addition it was scheduled four days per week in the INTENSIVE observations with Kokee Park. 

On many Saturdays the Intensive observations with Tsukuba, employing K4 recording technique 

were performed for about one hour. In comparison with the IVS telescopes, the RTW observed 

most of all. The table 2 summarizes the participation of RTW in the 24 hr observation sessions. 

It has to be mentioned that during the VLBI sessions the DORIS is switched off in order to 

avoid interference. 

IVS 2003 Annual Report 103 
Fundamentalstation Wettzell - 20m Radiotelescope BKG - Wettzell 

Name Affiliation Function 

Wolfgang Schluter BKG Head of the FSW 

Richard Kilger FESG Group leader RTW 

Eberhard Bauernfeind FESG mechanical engineer 

Ewald Bielmaier FESG technician 

Gerhard Kronschnabl BKG electronic engineer 

Table 1. Staff - members 

Working for 

RTW, TIGO, O’Higgins 

RTW 

RTW 

operator RTW 

RTW, TIGO (partly), 

program 

IVS R1 

IVSR4 

IVS R&D 

IVST2 

VLBA 

EUROPE 

VIE 

in total 

Christian Plotz 

I Raimund Schatz I FESG 

I Walter Schwarz I BKG 

number of sessions 

50 

49 

10 

3 

6 

4 

1 

122 

fier 1 FESG I electronic engineer 1 RTW I I I ~ ~~~ - Reinhard Zeitlho v 

Riidnlf Zernecke I FEW 30 (Dartlv) 

Table 2. RTW participation in the IVS 24 hr observing program 

4. Maintenance 

The intensive use of RTW requires maintenance in particular to avoid failures during the 

observations. Many problems have been caused by failures of the receiver cooling system, which 

mostly occur during hot summer periods. A lot of effort has been made to repair and to improve 

the cooling system. The antenna control unit (ACU) fails randomly, the reasons are unknown. 

If the ACU fails a restart is usually required. Azimuth motors had to be replaced and worn out 

couplings between the motor and the transmission had to be replaced. Random failures occurred 

also due to the shared memory of the Fieldsystem with specific RTW software. This problem was 

solved and no further failures were observed due to that problem. 

5. Technical Improvements 

The transition from the Mark 4 to the Mark 5A via Mark 5P has been successfully completed. 

Two Mark 5A systems were integrated, one of the units is modified for the Intensive observations 

as Intensives only require one hard disk per experiment and not a complete 8-pack. The second 

104 IVS 2003 Annual Report 
BKG - Wettzell bdamentalstation Wettzell - Mm Radiotelescope 

unit is used as a spare and also to test and to develop e-VLBI procedures. The tapes drives still 

are available. 

First tests for e-VLBI were performed in order to investigate the problems which occur on 

the national and intercontinental links. A 34 Mbps Internet connection is installed, for which the 

support is affordable. The link can be extended to 155 Mbps, as soon as it is affordable. The 

34 Mbps links allow the transmission of Intensive data to the correlator. Still a lot of work and 

coordination is needed. 

The last Fieldsystem version was implemented. 

6. Upgrade Plans for 2004 

During 2004 it is planned to replace the ACU in order to overcome the random failures which 

could not be explained. The eVLBI procedure for Intensive observations should be set up and an 

upgrade of the Mark 5A to Mark 5B is foreseen. 

IVS 2003 Annual Report 105 
Observatorio Astron6mico Nacional - Yebes Observatorio Astrondmico Nacional 

Observatorio Astron6mico Nacional - Yebes 

Francisco Colomer 

Abstract 

This report updates the description and details of the OAN facilities as an IVS network station. 

The 14 meter radiotelescope at Yebes participates regularly in the geodetic VLBI campaigns (EUROPE 

and CORE), as well as astronomical VLBI experiments as part of the European VLBI Network (EVN). 

The new 40 meter radiotelescope will start operation in Yebes during 2004, being available as soon 

as possible for geodetic VLBI. The institute staff is involved in technical developments, and scientific 

research in geodesy, astrometry and astrophysics. 

Figure 1. Status of construction of the new 40 meter radiotelescope of OAN at Yebes (Guadalajara, Spain), 

as of December 4th 2003. 

1. General Information: The OAN Facilities 

The Observatorio Astron6mico Nacional (OAN) of Spain, which is a department of the Instituto 

Geogr6fico Nacional (IGN, Ministerio de Fomento), operates a 14 meter radiotelescope at Yebes 

(Guadalajara, Spain). This facility is a network station of the IVS, and participates regularly in 

IVS 2003 Annual Report 106 
Observatorio Astrontjmico Nacional Observatorio Astronijmico Naciond - Yebes 

IVS 2003 Annual Report 107 

the geodetic VLBI campaigns to study the tectonic plate motions in Europe (project EUROPE), 

Earth rotation, and pole motion (project CORE). 

The 14 meter radio telescope, built in 1976, and nowadays used for VLBI, has been described 

in the 1999 lVS Annual Report. A photograph is included there, and a map of the Yebes site is 

in the report for year 2000. 

The VLBI equipment has been constantly upgraded. A Mark 5A unit was purchased from 

Conduant, and is now installed and operational. Due to the old control system, there is no 

direct interh between the Field System computer and the telescope. This fact has forced the 

development of several tools which, to date, allow automatic operation. 

On the other hand, studies are being conducted to connect the Yebes site to GEANT (the high 

speed transeuropean data network). Finally, we succeeded in obtaining protection against radio 

interference at Yebes in and out of the radioastronomy bands. The full text of this law is available 

at: 

http://rvv.oan.es/italaciones/cay/A21789-2179O.pdf 

The institute is currently involved in the construction of a new 40 meter radiotelescope (see 

Fig. 1) which is expected to be available for geodetic VLBI observations in mid 2005. Progress 

can be followed at the web address: 

http: //rvv. oan.es/instalaciones/telescopios/4W4h. shtml 

2. OAN StaE Working in VLBI projects 

Table 1 lists the OAN staff which are involved in VLBI studies, some of which can be found 

at the telescope (CAY) address. The associated members of IVS are indicated with an asterisk. 

Contact information is provided at the URL: 

http : //ww. oan. es/investigacion/astronomia/vlbi . shtml 

The VLBI activities are also supported by other staff like receiver engineers, computer managers, secretaries and students. 

Table 1. St& in the OAN VLBI group (Email: vlbiQoan.es). 

I Name I Background I Role I Dedication 1 Address 1 
Observatorio Astrondmico Nacional ~ Yebes Observatorio Astrondmico Nacional 

3. Status of the Geodetic VLBI Activities at OAN 

The main contribution of OAN to IVS is the realization of geodetic VLBI observations in 

the EUROPE and CORE projects: the OAN radio telescope at Yebes has participated in two 

EUROPE and three CORE experiments in 2003, failing to participate in two other EUROPE 

and one CORE due to technical problems with the old antenna control system and receiver. The 

institute also participates in the European VLBI Network (EVN) for astronomy (two sessions at 

X band in 2003), taking part in its logistics and carrying out technical developments. 

4. Future Plans 

The OAN 14-m radio telescope at Yebes goes on participating regularly in the campaigns for 

the EUROPE and CORE projects. 

The construction of the new 40 meter radiotelescope at Yebes is progressing well. The erection 

is expected to finish in May 2004. This telescope is expected to be operational at S/X bands in mid 

2005. Other frequencies of operation will be 4-7 GHz, 10-15 GHz, 21-24 GHz (first light receiver), 

Finally, studies are being conducted to connect the Yebes site to GEANT (the high speed 

30-32 GHz, 40-50 GHz, and 72-116 GHz. 

transeuropean data network). 

References 

[l] R. Bolaiio, P. de Vicente, C. Albo, C. Almendros: “Monitorizacin de 10s errores de posicionamiento de 

la antena de 14M para su us0 sincronizado con el terminal VLBI” , Informe TQcnico OAN 2003-6 

108 IVS 2003 Annual Report 
Geodetic Survey Division. Geomatics Canada. Natural Resources Canada Yellowknife Observatory 

Yellowknife Observatory 

Mario B6riib6, Calvin Klatt, ilnthony Searle 

Abstract 

The Yellowknife VLBI antenna is a 9 meter diameter antenna which was formerly the “MV-1” 

mobile antenna. The MV-1 was a proof-of-concept for mobile VLBI and in 1991 NASA and NOAA 

offered the system for use at Yellowknife. 

The antenna is located at the Yellowknife Geophysical Observatory and is operated by the Geodetic 

Survey Division. Natural Resources Canada. This report gives an update on recent activities. 

Figure 1. A snowy Yellowknife Geophysical Observatory 9m antenna. 

1. Overview 

Formerly the “MV-1” mobile antenna, the Yellowknife antenna waq used as a proof of concept 

for mobile VLBI under the ARIES (Astronomical Radio Interferometric Earth Surveying) program. 

Following the successful proof of concept, the MV-2 and MV-3 mobile antennas were built and 

used extensively during NASA’s Crustal Dynamics project. The MV-1 antenna was then stationed 

at Vandenberg Air Force Base. In 1991 NASA and NOAA offered the system to Energy, Mines 

and Resources, Canada, for use at Yellowknife. With support of the Crustal Dynamics Project 

the Yellowknife VLBI observatory came on the air in the summer of 1991. 

The antenna is located at the Yellowknife Geophysical Observatory and is operated by the 

Geodetic Survey Division, Natural Resources Canada. The Yellowknife Geophysical Observatory 

is operated by the Geological Survey of Canada, Pacific Division, Natural Resources Canada. 

IVS 2003 Annual Report 

- 

109 
Yellowknife Observatory Geodetic Survey Division, Geomatics Canada, Natural Resources Canada 

2. General Specifications 

0 Latitude : 62.48 North 

0 Longitude : 114.48 West 

0 Reflector: 9m 

0 Receiver : S and X cryogenic 

0 Azimuth speed : 40 degrees per minutes 

0 Elevation speed : 40 degress per minutes 

0 PCFS version : 9.5.3 

0 VLBI equipment : Mk I11 and thick tape drive. S2 data acquisition and recording terminal. 

0 Time standard : NR Maser 

0 GPS receiver : BenchMark 

3. Antenna Improvements 

Since being installed in Yellowknife, the MV-1 has not required any major upgrades. The 

antenna is parked every winter because the antenna is unable to operate in low temperatures 

(December till March). Once spring arrives, the Yellowknife team prepares the antenna for the 

upcoming season. 

Mechanical maintenance was performed in 1998 and the antenna has performed reasonably 

reliably since. The antenna control unit was replaced with one similar to that at Algonquin. Last 

year, antenna reliability was improved by upgrading antenna drives. 

Maintenance of NR maser was done as scheduled with power supply upgrade. 

4. Antenna Survey 

The Yellowknife antenna is surrounded by a high precision survey network which has been 

measured three times since 1990. This network has been precisely measured to obtain the geodetic 

tie between the VLBI, the GPS and the DORIS reference points with a precision of a few mm. 

5. Operations January 2003 - December 2003 

In 2003 Yellowknife was involved in 4 IVS-T2 (Terrestrial Reference Frame sessions), and in 5 

IVS-E3 sessions. 

110 IVS 2003 Annual Report 

Geodatisches Institut der Universitat Bonn Operation Center at the Geodetic Institute Bonn .. . 

The Bonn Geodetic VLBI Operation Center 

A. Mothnagel, D. Fischer, A. Miiskens 

Abstract 

In 2003 the GIUB Operation Center has continued to carry out similar tasks of organizing and 

scheduling various observing series as in 2002. 

1. Center Activities 

The GIUB VLBI Operation Center is located at the Geodetic Institute of the University of 

Bonn, Nussallee 17, D-53115 Bonn, Germany. It has been organizing and scheduling VLBI observing sessions for more than twenty years. The observing series organized and scheduled are the 

same as in 2002: 

Figure 1. Building of the Geodetic Institute 

0 Tsukuba - Wettzell UT1-UTC K4 Intensive Series 

The Tsukuba - Wettzell Intensive series for monitoring UT1-UTC has been continued as 

a joint project of the Bundesamt fiir Kartographie und Geodbie (BKG, Germany), the 

Geographic Survey Institute (GSI, Japan) and the Geodetic Institute of the University of 

Bonn (GIUB, Germany). 

IVS 2003 Annual Report 113 
Operation Center at the Geodetic Institute Bonn Geodatisches Institut der Universitat Bonn 

Dorothee Fischer ++49-228-732623 

Arno Miiskens ++49-228-525264 

Axel Nothnafzel ++49-228-733574 

31 single baseline sessions of about 90 minute duration were scheduled between April 12th 

and December 31th, 2003. Each one was carried out between 7.30 and 9.00 UT and was 

composed of 20 scans. Taking advantage of unattended observing at Tsukuba the sessions 

could be scheduled on Saturdays filling the weekend gaps of other series. The K4 system 

was employed for recording the data. In the scheduling of the individual sessions special 

emphasis was given to the use of equatorial sources and to the inclusion of sources spanning 

a wide range of elevations. 

BKG and GSI contribute observing time at the Wettzell and Tsukuba radio telescopes. GSI 

is responsible for the K4 correlation at Tsukuba and GIUB carries out the operation control, 

scheduling and analysis of the sessions. 

This series is observed roughly once per month (10 sessions in 2003) primarily for maintenance and stabilisation of the VLBI terrestrial reference frame as well as for Earth rotation 

monitoring as a by-product. This series is the follow-on of the International Radio Interferometric Surveying - South (IRIS-S) campaign with varying network configurations. 

0 Measurement of Vertical Crustal Motion in Europe by VLBI (EUROPE) 

Four sessions with Ny-hesund, Onsala, Wettzell, Simeiz, Madrid (DSS65), Yebes, Medicina, 

Matera, Noto, Svetloe, and Effelsberg (participated once) have been scheduled for precise 

station coordinate determination and long term stability tests. 

0 IVS-T2 series 

0 Southern Hemisphere and Antarctica Series (OHIG): 

Four sessions with the Antarctic stations Syowa (Japanese) and O’Higgins (German) plus 

Fortaleza, Hobart, Kokee, HartRAO and DSS45 have been organized for maintenance of the 

VLBI TFW and Earth rotation monitoring. 

dorothee.fischer@uni-bonn.de 

mueskens@mpifr-bonn.mpg.de 

nothnagel@uni-bonn.de 

2. Staff 

Table 1. Personnel at GIUB Operation Center 

Arno Muskens took care of the T2 and the OHIG sessions, Dorothee Fischer organized the 

Tsukuba - Wettzell series while Axel Nothnagel was responsible for the EUROPE project. 

114 IVS 2003 Annual Report 
CORE Operation Center -. - - NASA Goddard Space Flight Center 

CORE Operation Center Report 

Cynthia C. Thomas, Daniel MacMilIan 

Abstract 

This report gives a synopsis of the activities of the CORE Operation Center from January 2003 to 

December 2003. The report forecasts activities planned for the year 2004. 

1. Changes to the C0R.E Operation Center's Program 

The Earth orientation parameter goal of the IVS program is to attain precision at least as good 

as 3.5 ps for UT1 and 100 pas in pole position. 

The IVS program was started in 2002 and used the Mark IV recording mode for each session. 

The IVS program began using the Mark 5 recording mode in mid 2003. The following are the 

network configurations for the sessions for which the CORE Operation Center was responsible: 

IVS-R1: 52 sessions, scheduled weekly on Mondays, seven station network 

RDV: 6 sessions, scheduled evenly throughout the year, 18 to 20 station network 

IVS-UD: 10 sessions, scheduled monthly, seven station network 

2. IVS Sessions January 2003 to December 2003 

This section displays the purpose of the IVS sessions for which the CORE Operations Center 

is responsible. 

IVS-R1: In 2003, the IVSRls were scheduled weekly with a seven station network. There 

was a core network for each day plus two or three other stations. Hobart started observing 

in May 2003 when the station was upgraded to Mark 5. Hobart was the only "Mark 5 only" 

station during 2003. Wettzell, Westford, Kokee, and HartRAO were the only other stations 

that recorded on Mark 5 during this period. 

The purpose of the IVS-R1 sessions is to provide weekly EOP results on a timely basis. 

These sessions provide continuity with the previous CORE series. The "R" stands for rapid 

turnaround because the stations, correlators, and analysts have a commitment to make the 

the time delay fiom the end of recording to results as short as possible. The time delay goal 

is a maximum of 15 days. Participating stations are requested to ship tapes to the correlator 

as rapidly as possible. The "1" indicates that the sessions are on Mondays. 

RDV: There are six bi-monthly coordinated astrometric/geodetic experiments each year that 

use the full 10-station VLBA plus up to 10 geodetic stations. 

These sessions are being coordinated by the geodetic VLBI programs of three agencies: 1. 

USNO will perform repeated imaging and correction for source structure; 2. NASA will 

analyze this data to determine a high accuracy terrestrial reference frame; and 3. NRAO 

will use these sessions to provide a service to users who require high quality positions for 

small numbers of sources. NASA (the CORE Oeration Center) prepares the schedules for 

the RDV sessions. 

~~ 

IVS 2003 Annual Report 115 
CORE Operation Center NASA Goddard Space Flight Center 

0 R&D: The purpose of the 10 R&D sessions in 2003, as decided by the IVS Program Committee, was to provide additional information to understand possible differences between the 

IVS-R1 and the IVS-R4 sessions. In 2002, the IVS-R4 sessions appeared to be achieving 

better earth orientation results with a lower data rate (56 Mbps vs. 256 Mbps). The R&D 

sessions were scheduled with a network similar to the IVS-R4 network but using the IVSRl observing mode. The R&D experiments used a 7-station Northern-hemisphere geodetic 

network and were scheduled monthly, adjacent to IVS-R4 sessions with the same stations 

except one. Westford participated in the R&D replacing Fortaleza since Fortaleza has not 

been upgraded to Mark IV. 

3. Current Analysis of the CORE Operation Center’s IVS Sessions 

Table 1 lists the average formal errors for X-pole, Y-pole, UT1, and nutation parameters 

estimated from the R1, R4, R&D, T2, and RDV sessions that took place during 2003. The R1 

EOP parameters agree better with C04 than those from R4, T2, and R&D sessions although 

this may be due in part to the better formal uncertainties of the Rls and the weighting scheme 

employed in generating C04. Clearly X-pole and DPSI are not determined as precisely with R4 

compared to R1. Formally, the R&D EOP precision is not significantly different from R4 precision 

(except somewhat in X-pole) but there are some significant differences in the comparison with 

C04. But with only 10 sessions, we may not be able to make statistically significant conclusions. 

For example, removing one session reduces the wrms difference relative to C04 for UT1 to 2.7 us. 

Table 1. Table 1. Average EOP Formal Uncertainties 

Session Type X-pole Y-pole UT1 DPSI DEPS 

R1 52 50 1.9 114 47 

R4 81 69 2.9 163 65 

T2 157 157 6.0 335 145 

R&D 65 70 2.4 143 60 

RDV 33 37 1.8 72 28 

(Pas) (Pas) (PS) (mu4 (mu4 

Table 2. Table 2. WRMS Differences Relative to C04 

Session Type X-pole Y-pole UT1 DPSI DEPS 

(Pa4 (Pas) (PS) (mu4 (mus) 

R1 61 71 2.9 113 56 

R4 97 66 3.3 165 77 

T2 158 99 6.2 164 81 

R&D 94 103 9.2 122 36 

RDV 44 32 2.5 79 28 

116 IVS 2003 Annual Report 
NASA Goddard Space Flight Center CORE Operation Center 

Name 

Tom Buretta 

Brian Corey 

Irv Deigel 

John Gipson 

Frank Gomez 

David Gordon 

Ed Himwich 

Chuck Kodak 

Cindy Villiard 

Dan MacMillan 

Leonid Petrav 

4. The CORE Family 

Table 3 lists the key technical personnel and their responsibilities so that everyone reading this 

report will know whom to contact about their particular question. 

Responsibility Agency 

Recorder and electronics maintenance Haystack 

Analysis Haystack 

Maser maintenance Honeywell 

SKED program support and development NVI, Inc./GSFC 

Software engineer for the Web site Raytheon/GSFC 

Analysis Raytheon/GSFC 

Network Coordinator NVI, Inc./GSFC 

Receiver maintenance Honey well 

Analysis Ray theon/G SFC 

Analysis NVI, Inc./GSFC 

Analvsis NVI, Inc./GSFC 

Table 3. Key Technical Staff of the CORE Operations Center 

-- - 

Nancy Vandenberg 

William Wildes 

Organizer of CORE program 

Procurement of materials necessary for CORE 

NVI, Inc./GSFC 

GSFC/NASA 

Dan Smvthe I TaDe recorder maintenance I Havstack Y I= I u 

Cynthia Thomas I Coordinate master observing schedule and I NVI, Inc./GSFC 

I prepare observing schedules I 

I operations 

5. Planned Activities during 2004 

The CORE Operation Center will continue to be responsible for the following IVS sessions 

during 2004. 

0 The IVS-R1 sessions will be observed weekly and recorded in a Mark rV mode. We will 

increase the number of stations using Mark 5 recorders as determined by the Coordinating 

Center. 

0 The IVS-R&D sessions will be observed 10 times during the year. The purpose of the R&D 

sessions in 2004 as determined by the IVS Observing Program Committee is to study how 

to use Gb/s data rate for geodesy. Phase delay will be attempted and the SNRs will be set 

high. 

0 The RDV sessions will be observed 6 times during the year. 

IVS 2003 Annual Report 117 
NEOS Operation Center at USNO U.S. Naval Observatory 

U.S. Naval Observatory Operation Center 

Kerry Kingham, M.S. Carter 

Abstract 

This report covers the activities of the NEOS Operation Center at USNO for 2003. The Operation 

Center schedules IVS-R4 and the Intensive experiments. 

1. VLBI Operations 

NEOS operations in the period covered consisted, each week, of one 24-hour duration IVSR4 observing session, on Thursday-Friday, for Earth Orientation, together with four daily onehour duration “intensives” for UT1 determination. The operational IVS-R4 network has included 

VLBI stations at Gilmore Creek (Alaska), Kokee Park (Hawaii), Wettzell (Germany), Fortaleza 

(Brazil), Ny- Wlesund (Norway), Algonquin Park (Canada), TIGO (Chile), Svetloe (Russia), Hobart 

(Australia), Onsala (Sweden), and Matera (Italy). A typical R4 consists of 7 stations. The stations 

for the IVS-Intensives were Kokee Park and Wettzell. 

All sessions are correlated at the Washington Correlator, which is located at USNO and is run 

by NEOS. 

2. Staff 

M. S. Carter continues as the only staff member of the NEOS Operation Center. 

118 IVS 2003 Annual Report 

Geodiitisches Institut dm Universitat Bonn Bonn MPIfR/BKG - Correlator 

The Bonn Astro/Geo Mark IV Correlator 

Arno Miiskens, Walter Alef 

Abstract 

The Bonn Mark TV VLBI correlator is operated jointly by the MPIfR (Bonn), the GIUB (Bonn) 

and the BKG (Frankfurt). In the course of 2003 eight Mark5A systems have been installed. The 

amount of data recorded with Mark 5A has reached 40%. 

1. Introduction 

The Bonn Mark IV correlator is hosted at the Max-Plan&-Institut fii Radioastronomie 

(MPIfR)', Bonn, Germany. It is jointly operated by the MPIfR and by the BK@ in cooperation with the GIUP. It is a major correlator for geodetic observations, and MPIfR's astronomical 

projects. 

2. Present Status and Capabilities 

The correlator in Bonn is one of four world-wide Mark IV VLBI data processors. It has been 

operational since 2000. It consists of the standard 16 station capable correlator unit and nine 

Honeywell/Metrum 96 tape drives, each of which is connected to the correlator via a standard 

Mark IV station unit and high speed data links. 

The tape units are all equipped with digitally-switched equalizer boards developed in Bonn 

which allow playback of thin (and thick) tapes recorded at normal (80/135 ips) and double speed 

(160/270 ips). 

In the course of 2003 eight Mark 5 disc-recorder units were added to the data processor. The 

tape drives were rearranged to make space for a rack which can hold seven Mark 5 units (see 

Fig 1). The Mark 5 units are connected to the station units in parallel to the tape drives. Data 

from the tape units is fed into input for head one and data from Mark 5 into input for head 

two. As the tape drives me equipped with only one playback head the second input is otherwise 

unused. Playback from tape or disc can be selected via a simple software switch. With this setup 

all 32-track modes can be correlated from both tapes and discs. 64track modes can be correlated 

with modest re-cabling with either one or two correlation passes depending on the details of the 

experiment. 

The supported formats on tape and disc are Mark IIIA, Mark IV and VLBA, both Mark IV 

and VLBA with 1- or 2-bit sampling and barrel-rolling. Fan-in modes are not supported while all 

the fan-out modes 1:l and 1:2 and 1:4 are possible. Up to 16 frequency channels can be used, both 

upper and lower sidebands. Channel bandwidths of 2, 4, 8 and 16 MHz are available. Observing 

modes with 512 and 1024 Mbits/s have been correlated successfully without major problems, where 

1024 Mbits/s can only be realized with Mark 5 systems. 

The correlation is done in a scan-based way; the overhead for each scan is about 2 to 3 minutes 

for tapes and 1 minute for the disc recordings. It takes less than about 5 seconds to synchronize 

http: //www.mpifr-bonn.mpg.de/div/vlbicor/index_e.html 

2Bundesamt fiir Kartographie und Geodbie, Fkankfurt, Germany, http://www.ifag.de/Geodaesie/gf-ehtm 

3Geodetic Institute, University of hnn, Germany, http://giub.geod.uni-bonn.de/vlbi 

TVS 2003 Annual Report 121 
Bonn MPIR/BKG Correlator Geodatisches Institut der Universitat Bonn 

Figure 1. Tape drives with stations units on top, Mark 5 units in a rack, and the correlator surrounded by 

two more tape drives, Mark 5 units, and station units. The correlator control console is visible on the desk 

in the center. 

the tapes while the synchronization of Mark 5 systems is instantaneous. Up to two of the phasecal tones can be extracted, but only one is used by the fringe-fitting software to align different 

frequency channels. The geometric correlator model is CALC 8. The pre-averaging time is flexible 

from 1 to 5 seconds. Shorter pre-averaging times are possible, but can only be sustained by 

correlating fewer stations simultaneously. 

The instaIled computer power is sufficient to handle all nine tape units in a correlator mode 

with 32 lags, auto-correlations and 1 s pre-averaging. Full polarization correlation is possible with 

8 stations simultaneously. For improved spectral line resolution, correlator modes with up to 1024 

complex lags have been used. Correlation setup, data inspection, fringe-fitting, and data export 

is done with a separate workstation. Per year about 300 to 400 GBytes of correlated data are 

generated. The total disk space available for data handling at the correlator is 380 GBytes. Data 

security is guaranteed by using a file system with redundancy (RAID level 5) and by daily back-up 

of the data on a 120 GB disk of a low-end Linw PC. 

The correlator software has become fairly stable in the last two years, and the only major 

changes provided by Haystack addressed the handling of Mark 5 data. The track-finding software 

for the tape drives was modified in Bonn to avoid accidental correlation with one head-pitch offset. 

The software of the Mark 5 systems is still under constant development and has to be upgraded 

regularly, but the reliability of the disk systems is already higher than that of the tape drives. 

An up-tedate list of correlator capabilities can be found on the Internet under http://www.mpifrbonn.mpg.de/EVN/MK4CORstatus. 

3. Correlator Operations and Statistics 

The people in the geodetic group at the Bonn correlator are 

0 Arno Miiskens : group leader, overall experiment supervision, scheduling of T2 and OHIG 

series 

122 IVS 2003 Annual Report 
Geodiitisches Institut der Universitat Bonn Bonn MPIfR/BKG Correlatm 

0 Izabela Rottmann : experiment supervision (part time; left in 2003) 

0 Alessandra Roy : experiment supervision (part time) 

0 Alexandra Hofer : experiment supervision (started in late 2003) 

10 student operators for the night shifts and the weekends (60 hrs / week) 

0 Alan Roy : measurement and correction of tropospheric path length variations 

Experiment supervision includes the preparation of correlator control files, fringe searching, supervision of the correlation process, preparation of the re-correlation, the correlator report, database 

generation, archiving, and the supervision of tape shipments. 

MF'IfR supports IVS correlation with 

0 Walter Alef : correlator manager, correlator software maintenance and upgrades, and computer system administration 

0 David Graham : technical development, consultant 

0 Heinz Fuchs : correlator operator, responsible for correlator operator scheduling, daily oper0 Hermann Sturm : correlator operator, correlator support software, tape shipping 

0 Michael Wunderlich : engineer, correlator and playback drive maintenance, Mark 5 support 

0 Arno Freihold : engineer, correlator maintenance, digital BBC development 

0 Rolf Maens : technician, playback drive maintenance, Mark 5 support 

The Bonn group correlated in 2003: 

0 T2 experiments : 8 

0 R1 experiments : 30 

0 EURO experiments : 5 

0 CONT02 experiments : 1 

0 OHIG experiments: 3 

Experience with IVS-R and other 24 hour observations shows it has been possible to reduce the 

processing factor (correlation time/observe time) by about 20 to 30% (see Fig 2), and the amount 

of re-processing by almost 75%. This is mostly due to reduced setup time and less operator 

interaction now that up to four stations record on Mark 5 systems, to more stable station unit 

software, and improved track-finding software. 

The geodetic backlog from 2002 vanished towards the end of 2003 with the help of the improved 

throughput and less geodetic observing and correlation. The overall usage of the correlator in 2003 

for geodetic correlation was 57% compared to 70% in 2002. 

ations, and tape shipping. 

IVS 2003 Annual Report 123 
Bonn MPIfR/BKG Correlator Geodatisches Institut der Universitat Bonn 

R1 2.24 

T2 2.63 

i CI) 

cu 

c 

8 EURO 2 83 

c 

OHlG 

Q) 

C0214 2.83 ... 

Average 2.37 

I I I I 1 I 

0 0.5 1 1.5 2 2.5 3 

Processing Factor 

Figure 2. The processing factor could be reduced by about 20 to 30% compared to 2002. This is mostly 

due to the conversion of 2 to 4 stations to Mark 5 recording system. 

4. Outlook 

It is expected that in the course of 2004 all geodetic and EVN observations will be done 

exclusively with Mark 5. The tape drives will still be maintained because of joint 3mm-observations 

with the VLBA which does not yet have funding for Mark 5. 

MPIfR will support the development of the Mark 5B system by re-designing the serial highspeed data links between the correlator and the planned station unit part of the Mark 5B units. 

It is also planned to fully upgrade the correlator to Mark 5B systems in 2004/2005. 

The development of fully digital base-band converters (dBBCs) is also supported at MPIfR. 

This project lead by Gino Tuccari from Noto will eventually allow replacing the aged analog BBCs 

with new hardware. Improved bandpass characteristics as well as higher data-rates will help to 

increase the precision of the geodetic observables. 

124 IVS 2003 Annual Report 
MIT Haystack Observatory Haystack Correlator 

Haystack Observatory VLBI Correlator 

Mike Titus, Roger Capppallo, Brian Core3 Arthur Niell 

Abstract 

This report presents the status of the Haystack Correlator, focusing on its activities, its current 

and future hardware capabilities, and its staff. 

Figure 1. 

containing 4 SUs, and 1 rack containing 2 Mark 5A units and a decoder. 

Partial view of Haystack Mark IV correlator, showing correlator rack, 3 tape units, 1 rack 

1. Introduction 

The Mark IV VLBI correlator of the MIT Haystack Observatory, located in Westford, Massachusetts, is supported by the NASA Space Geodesy Program and by the National Science Foundation. The available correlator time is divided approximately equally between processing geodetic 

VLBI observations for IVS and processing millimeter-wave radio astronomy observations for the 

Coordinated Millimeter VLBI Array. In addition to its role as an operational processor, the 

Haystack Correlator also serves as a development system for testing new correlation modes and 

hardware improvements and for diagnosing correlator problems encountered at Haystack or at one 

of the identicd correlators at the U.S. Naval Observatory and the Max Planck Institute for Radioastronomy. This flexibility is made possible by the presence on-site of the team that designed 

the correlator hardware and software. 

2. Summary of Activities 

Integration and testing of Mark 5 on the correlator has continued throughout the year. The 

two initial Mark 5P units have been replaced with Mark 5As, and two more have been added. 

Production use of Mark 5 has steadily increased, resulting in frequent upgrades with enhanced 

IVS 2003 Annual Report 125 
Haystack Correlator MIT Haystack Observatory 

software on the Mark 5s and correlator in order to improve the smoothness of operation. The 

increased use of Mark 5 recordings and the effects of other improvements in software, such as the 

elimination of “forks” and byte slips, have resulted in improved efficiency. For R1 experiments 

the efficiency factors are now routinely below 2.0 - typically 1.8 or so - whereas previously they 

were typically between 2 and 2.5. This is reflected in the improved efficiency of all the Mark IV 

correlators, which have significantly reduced or completely eliminated their backlogs over the last 

year. 

Another area of continued focus has been e-VLBI. Several e-VLBI test experiments, and the use 

of e-VLBI for quick feedback fringe tests, have demonstrated the value of e-VLBI in an operational 

sense. One particular accomplishment worthy of note is the turnaround of a Kashima-Westford 

Intensive session within 24 hours (27 June 03). More recently, the focus has been on automating 

the transfer process and the transfer of entire 24-hour sessions (particularly Kashima data from 

the CRF series). 

In addition to these developments, other improvements and fixes continue to be implemented 

on a time available or as needed basis. These are intended to improve operations or data quality, 

or to correct problems. It should be noted that some fixes and improvements come as a byproduct of Mark 5 or e-VLBI related development, showing that new technology development and 

improvements of a more general nature are often coupled. 

3. Experiments Done 

Since January 2003, 40 experiments have been processed at the Haystack correlator. This 

total subdivides into 19 Rls, 8 R&Ds, 3 CONTs and 10 test experiments. The test experiments 

cover an assortment of e-VLBI, Mark 5, correlator software, and station/equipment tests. The 

increase in 24-hour production experiments over last year (+4), reflects the better throughput due 

to improved efficiency. 

4. Current/Future Hardware and Capabilities 

Currently functional hardware installed on the system consists of 7 tape units, 4 Mark 5 units, 7 

station units, 16 operational correlator boards, 2 crates, and miscellaneous other support hardware, 

with the ability to process all baselines for 7 stations simultaneously in the standard geodetic 

modes. By late 2004, development of the Mark 5B might allow the correlation of more than 7 

stations, due to the ability to add Mark 5 units without the need for an accompanying station unit. 

We expect to remove tape drives from the system as more stations move to exclusively recording 

on Mark 5. 

5. Staff 

Staff who participate in aspects of Mark IV development and operations include: 

5.1. Software Development Team: 

John Ball - operator interface; playback; Mark 5/e-VLBI development 

0 Roger Cappallo - leader; system integration 

126 IVS 2003 Annual Report 
MIT Haystack Observatory Haystack Comelator 

0 Kevin Dudevoir - correlation; maintenance/support ; e-VLBI development 

0 David Lapsley - e-VLBI development 

0 Colin Lonsdale - post processing 

0 Alan Whitney - system architecture; Mark 5/e-VLBI development 

5.2. Operations Team: 

0 Peter Bob - correlator maintenance 

0 Tom Buretta - playback drive maintenance 

0 Brian Corey - experiment correlation oversight; station evaluation; technique development 

0 Dave Fields - playback drive maintenance; Mark 5 installation/maintenance 

0 Ellen Cellini - correlator operator 

0 Glenn Millson - correlator operator 

0 Arthur Niell - technique development 

0 Don Sousa - correlator operator; experiment setup; tape library and shipping 

0 Mike Titus - correlator operations oversight; experiment setup; computer services; software 

0 Ken Wilson - correlator maintenance; playback drive maintenance 

& hardware testing 

6. Conclusion/Outlook 

Continued integration and expansion of Mark 5 units into the correlator will be a major effort 

in the next year. Mark 5B development might make possible an increase in the number of stations 

that can be processed simultaneously. Another major priority will be development of e-VLBI. 

Efforts to improve operations and efficiency will continue, and all of the above tasks should result 

in further improved data quality and increased data throughput for the Mark 4 correlators in the 

coming year. 

~ 

IVS 2003 Annual Report 127 
IAA Correlator The Institute of Applied Astronomy 

IAA Correlator Center 

Valery Gratchev 

Abstract 

In 2003 the IAA S2 correlator TISS-1M processed six sessions for radio source structure investigation. Also, some revisions and updates were made for control and post processing programs. The 

Institute of Applied Astronomy is developing Altera FPGA-based scalable correlator PARSEC with 

Mark4 specification. We have developed the prototype correlator MicroPARSEC. PCI-bus correlator 

board MicroPARSEC has standard office PC board format. 

1. General Information 

The S2/Mark3 correlator (Figure l), new correlator MicroPARSEC and PARSEC are located 

at and staffed by the Institute of Applied Astronomy in Saint-Petersburg, Russia. The correlators 

are sponsored and funded by the Russian Academy of Sciences, by the Russian Foundations of 

Basic Research and by the Russian Ministry of Sciences and Technologies. Dedicated to processing 

geodetic, astrometric and astrophysical VLBI observations, the general role of the correlators is as 

an operational processor for VLBI observation in Russia. 

Figure 1. S2 correlator TISS-1M at the IAA correlator center in Saint-Petersburg. 

There are three racks with S2-PT terminals at the center of the back plane and six racks for 

128 IVS 2003 Annual Report 
The Institute of Applied Astronomy IAA Correlator 

correlator devices on the left and right from play back terminals. On the right of front plane, there 

is a table with control computer with correlation software and post processing program PrOut. 

2. Correlation Processing 

In 2003, we processed the following S/X experiments at Svetloe-Zelenchukskaja baseline for 

0406 February and 28 February 2003, 

0405 March 08-16 March 2003, 

2@28 April 2003, 22-25 May 2003, 

09-12 August 2003, 

1417 September 2003. 

Also, we made some fringe tests to investigate the antenna pointing accuracy at Svetloe and 

radio source mapping by using of amplitude method. 

Zelenchukskaija. 

3. New Correlators 

The Institute of Applied Astronomy is developing Altera FPGA-based scalable correlator PARSEC with Mark4 specification. The correlator unit uses PCI-bus correlator boards, standard CompactPC1 hardware with single board Intel Pentium control computer and standard Linux operating 

system (Figure 2). We have estimated that it is possible to provide 4station and 16-channel 1- or 

2-bit data processing by using single correlator unit with Mark5 VSI compatible playback system 

for VLBI and e-VLBI. 

We have developed the prototype conelator MicroPARSEC. PCI-bus correlator board MicroPARSEC (Figure 3) has the following features: standard office PC board format, single board 

supports 2 cross-correlation channel for one baseline, operation at input data rate to 64 Msamples/sec/channel, 1 or 2 bit sampling, integrated input data rate to 512 Mbit/s, the board can be 

connected directly to Canadian S2-RT or S2-PT. 

The features of the IAA correlators are summarized in Table 1. 

We have produced and tested four MicroPARSEC correlator boards, which also may be used as 

scalable spectrum analyzer for station phase cal extraction and other different system diagnostic 

and/or spectral line real time observation data processing in single dish mode on our radio telescopes in Svetloe, Zelenchukskaya and Badary. We are going to start volume production in order 

of the correlator board MicroPARSEC for standard office PC with standard Windows 98/2000/XP 

operating system and special control and monitor program developed in IAA. 

4. Updating the Control and Post Processing Programs 

One of the major updates was made to the control correlator program for serial processing 

data of geodetic S2 VLBI observation at Russian stations. The program is installed in IBM PC 

Pentium I11 under Windows 98. For the dculation of model for delay tracking and fringe stopping 

the program package ERA developed at the IAA is used. 

The post processing program PrOut was updated to extract the observables from serial raw 

correlator output data. The PrOut in Visual C++ v.6.0 is installed on IBM PC Pentium N 

computer under Windows XP operating system. 

~~~ 

IVS 2003 Annual Report 129 
IAA Correlator The Institute of Applied Astronomy 

Main logic 

Table 1. Comparison of the correlators at the IAA 

Standard logic 1C 

Year of production 

Data input format 

Number of channels 

Number of lags 

Processing rate/ch 

Sample bit 

Phase resolution in fringe rotation 

Phase cal detect 

Accumulation counter 

Parameter period 

Pulsar gate 

Data transfer 

Baselines 

TISS-1M 

1993 

Mark3 

30 

8 

4 Mbps 

1 bit 

32 bit 

1 Hz i 1 MHz 

24 it 

5ms i 1s 

No 

s2 

3 

MicroPARSEC 

2003 

S2/VSI 

2 

64 

64 Mbps 

1 or 2 bit 

32 bir 

1 Hz i 4 MHz 

30 bit 

50ms + 50s 

YeS 

FPGA 

S2/Mark5B 

1 

PARSEC 

2004 

16 

64 

64 Mbps 

1 or 2 bit 

32 bit 

1 Hz i 4 MHz 

30 bit 

50ms f 50s 

Yes 

FPGA 

S2/Mark5B 

6 

S2/VSI 

Figure 2. 

specification. 

The prototype of Altera FPGA-based scalable correlator PARSEC with Mark4 

5. Conclusion/Outlook 

Full construction of PARSEC correlator will be a major effort in 2004. The development, 

integration and expansion of Mark5 VSI compatible units will also be a priority. 

130 IVS 2003 Annual Report 
The Institute of Applied Astronomy I4A Correlator 

Figure 3. PCI-bus correlator board MicroPARSEC. 

IVS 2003 Annual Report 131 
Kashima VLBI Correlators Communications Research Laboratory 

Kashima VLBI Correlators 

Mamoru Sekido, Yasuhiro Koyama 

Abstract 

Tape-based correlation system of KSP has been used for processing of domestic VLBI experiments and Antarctica VLBI experiments. Except for KSP VLBI correlation system, overall activity 

in Kasihma/CRL related with VLBI correlator is introduced. Development of software correlators and 

status of giga-bit VLBI system are also described. 

1. General Informat ion 

This component used to be titled “KSP-VLBI Correlation Center” until the previous issue. 

However the “Key Stone Project” had already closed and the correlators are now operated by 

VLBI group of Kashima Space Research Center. Thus the title was changed to Kashima VLBI 

Correlators. Corresponding to the change of title, the view of description was expanded from KSP 

correlation system to overall correlator related activity at Kashima/CRL. 

The KSP correlation system (Kiuchia, 1999) is capable to process 4 stations 6 baselines tapebased VLBI data simultaneously. The data rate per station is 64 Mbps, 128 Mbps, or 256 Mbps 

with 16 channels 1 bit sampled data. We have other 6 one-baseline correlator units for real-time 

VLBI of the KSP (Kiuchib et al., 1999), although it was not used after the shutdown of KSP. Then, 

for upgrading processing capability of correlation system at Geographical Survey Institute (GSI) 

from 3 baselines to 6 baselines, 3 correlation units and one recorder interface units were loaned to 

GSI. 

2. Experiments Processed by KSP System 

Figure 1 shows the view of operation room of KSP correlation system. 

Figure 1. Operation room of KSP correlation system 

The names of experiments processed by the KSP correlator in 2003 are as follows: 

JADE series: Geographical Survey Institute (GSI) has been organizing domestic geodetic VLBI 

experiments with its own stations. Additionally GSI accepts any stations to join the exper132 IVS 2003 Annual Report 
Communications Research Laboraton- Kashima VLBI Correlators 

iments in omnibus style. This type of experiments are named JADE series and it is useful 

for Universities to determine their antenna coordinates in the ITRF and to perform geodetic 

study with single antenna. One of the cases is llm antenna in Gifu University. However, correlation processing facility is limited at GSI and ClU. Then correlation processing between 

Gifu and other stations were performed with KSP correlator at Kashima. 

SYOWA series: National Institute of Polar Research (NIPR), GSI, and National Astronomical 

Observatory (NAOJ) have been organizing a series of VLBI experiments to measure the 

Antarctica plate motion. Hobart, HartRAO, and Japanese Syowa VLBI stations were joined. 

The data observed at Hobart and HartRAO were originally recorded by S2 recorder, then 

the data are copied to K4 tapes at Mitaka. And several sessions of this series of experiments 

were processed by KSP correlator in Kashima. 

3. Giga-bit Correlators GICO-I and GICO-I1 

Correlation processor with 1 giga-bps system (Nakajima et al. 2001) was developed in combination with 1 Gbps VLBI data recorder GBR-1000. And the next upgraded giga-bit correlator 

GICO-I1 (Nakajimaa et al., 2000), which has 2 correlator chip sets accepting 2 Gbps data stream, 

was developed and it has been used for the fist real-time giga-bit VLBI system on GALAXY 

network three years before (Nakajimab et al., 2000). These giga-bit VLBI system was used for 

verification of capability for geodetic VLBI application in 2003 (Takeuchi et al., 2003). Giga-bit 

VLBI system is displayed in Figure 2. 

Figure 2. The Giga-bit VLBI system. The system in the left tall rack is GICO-I and that in the right short 

rack is GICO-11. 

I 4. Software Correlators 

PC-based data VLBI system named “K5 system” has been developed (Kondo et al., 2003). 

The data compatibility between K5 and Mark 5 has been confirmed in some recording modes and 

intercontinental e-vlbi experiment for UT1 measurement has been performed on Kashima-Haystack 

baseline (Koyama et al., 2003; Whitney and Koyama 2003). The K5 VLBI system is composed of 4 

PCs with each I€’-VLBI sampler board. One IP-VLBI sampler board has 4 channels with various 

IVS 2003 Annual Report 133 I 
Kashima VLBI Correlators Communications Research Laboratory 

sampling modes. The IP-VLBI board has also been used for VLBI experiments for spacecraft 

navigation (Ichikawa et a1.,2003). The detail of the spacecraft observation will be discussed in the 

IVS General Meeting in 2004. Giga-bit sampler with VSI interface is also under development and 

corresponding high speed FX type software correlator has been also developed for the GIGA bit 

sampling data (Kimura and Nakajima. 2002, Kimura et al., 2003). This software correlator has 

flexibility to choose any lag number and is optimized to perform any number of baselines of Gigabit data within a constant time interval, when the same number of PCs with observation stations 

are used for processing. Another activity in software correlator is “VLBI@HOME” project (Figure 

3), which performs correlation processing with screen saver mode. It is a kind of approach for 

distributed correlation processing like a SETIQHOME. VLBI data might be processed on many 

office PCs in the darkness of midnight in near future. 

Figure 3. Logo mark of VLBIQhome. 

5. Staff 

0 Tetsuro Kondo is responsible for overall operations and performance, and he is developing 

software correlator for geodetic purpose. 

0 Yasuhiro Koyama is in charge of correlation processing system and working for e-VLBI on 

intercontinental baseline. 

0 Junichi Nakajima is in charge of giga-bit VLBI system. 

0 Mamoru Sekido is in charge of KSP correlation system and working for VLBI application for 

spacecraft navigation. 

0 Shinobu Arimura is in charge of routine correlation processing operation with KSP correla0 Moritaka Kimura is working for development of hardware giga-bit correlator and a high speed 

tors. 

giga bit software correlator. 

0 Hiroshi Takeuchi is working for development of VLBI correlation system in screen saver 

mode. 

134 IVS 2003 Annual Report 
Communications Research Laboratory Kashima VLBI Correlators 

References 

[l] Ichikawa R., Sekido M., Osaki H., Koyama Y., Kondo T, and NOZOMI VLBI group, VLBI application 

for spacecraft navigation (NOZOMI) Part I -Overview-: IVS CRL-TDC News No. 22, pp.10-11, 2003 

[2] Kiuchi" H., Kondo T., and Sekido M.: Correlation Processing System, J. of Comm. Res. Lab. Vol. 46, 

pp.47-54, 1999. 

[3] Kiuchib H., Kondo T., Sekido M., Koyama Y., Imae M., Hoshino T., and Uose H.: Real-Time VLBI 

Data Tkansfer and Correlation System, J. of Comm. Res. Lab. Vol. 46, pp.83-90,1999. 

[4] Kimura M., and Nakajima J., The implementation of the PC based Giga bit VLBI system: IVS CRZTDC News No. 21, pp.31-33, 2003 

[SI Kimura M., Nakajima J., Takeuchi H., and Kondo T., 2-Gbps PC Architecture and Gbps data pre 

cessing in KS/PC-VSI IVS CRL-TDC News No. 23, pp.12-13,2003 

[6] Kondo T., Koyama Y., and Os& H., Current Status of the K5 Software Correlator for Geodetic VLBI 

IVS CRL-TDC News No. 23, pp.18-20,2003 

[7] Koyama Y., Kondo T., and Osaki H., Rapid UT1-UTC estimation from Westford-Kashima e-VLBI 

experiment, IVS CRL-TDC News No. 12, pp.69,2003 

[8] Nakajima". J., Koyama Y., Sekido M.,Ichikawa R., and Kondo T.: Approved upgrade of the Gbit VLBI 

system expansion, IVS CRL-TDC News No. 17, pp.25,2000 

[9] Nakajimab. J., Koyama Y., Kondo T., -do M., Takahashi Y., Kawai E., Okubo H., Kiuchi H., 

Kawaguchi N., Kimura M., Fujisawa K., and Kobayashi H.: Optical Linked VLBI in Japan,IVS CRLTDC News No. 16, pp.1518,2000 

[lo] Nakajima. J., Koyama Y., Sekido M., Kurihara N., Kondo T., Kimura M., and Kawaguchi N.: 1-GBPS 

VLBI, THE FIRST DETECTION OF FRINGES, Ezpen'mental Astronomy Vol. 11, pp.57-69,2001. 

1111 Takeuchi H.,Nakajima J., Kimura M., Koyama Y., and Kondo T., Geodetic VLBI experiments Using 

VSEbased Giga-bit VLBI System, IVS CRL-TDC News No. 23, pp.2325,2003 

[12] Whitney A., and Koyama Y., Kashima-Westford UT1 RRsults via e-VLBI in Less Than 24 Hours, IVS 

Newsletter Issue 6, pp.7, 2003 

IVS 2003 Annual Report 135 
Tsukuba VLBI Correlator Geographical Survey Institute, Japan 

Tsukuba VLBI Correlator 

Morito Machida, Masayoshi Ishimoto, Shinobu Kurihara, Kazuhiro Takashima 

Abstract 

This is a report of activities at the Tsukuba VLBI Correlator in 2003. 

1. General Information 

The Tsukuba VLBI Correlator is located at Geographical Survey Institute(GS1) in Tsukuba, 

Ibaraki, Japan. The facility holds the K-4 (KSP) correlation system for processing geodetic VLBI 

experiments. It consists of three correlator units, three tape drive units housed in auto tape changers and a HP workstation to control the system and run Interactive CALC/SOLVE (NASA/GSFC). 

The workstation also provides a working area for executing correlation software, Oxtail Version 

2.0, which was updated in March 2003 as described in the previous Annual Report. 

Figure 1. Diagram of K-4 (KSP) correlation system at the Tsukuba VLBI Correlator 

2. Correlation Processing 

We extended the operational time due to the increased demand for geodetic correlation. During 

2003, 11 domestic experiments, 28 intensive sessions and some fringe tests have been processed 

at the Tsukuba VLBI Correlator. The JADE (Japanese Dynamic Earth observation by VLBI) 

series are set monthly by GSI for monitoring plate motions and maintaining the International 

136 IVS 2003 Annual Report 
Geographical Survey Institute, Japan Tsukuba VLBI Correlator 

Terrestrial Reference Rame in Japan. GSI’s original VLBI network (GARNET or GSI Advanced 

- Radiotelescope &work) stations regularly take part in the JADE experiments, and other stations 

with K-4 recording system can join JADE to determine their antenna positions. Due to that the 

capacity is not enough to process the data from all participating stations at once, we correlated only 

the data from the GARNET stations and the Mizusawa station at the Tsukuba VLBI Correlator, 

and the data from other participating stations were correlated by Gifu University or CRL at the 

KSP-VLBI Correlation Center of Kashima Space Research Center under an agreement between 

CRL and GSI. In 2003, it took several months to get all data put together into Mark I11 databases 

with several non-GARNET stations joined in JADE, and we handled as follows. As preliminary 

stage, we processed the GARNET and Mizusawa station’s data and made databases to check the 

quality of the results. After these databases were submitted to IVS, we reprocessed all baselines 

by adding the data of the other stations that were sent later from the KSP-VLBI Correlator at 

Kashima. We resubmitted it informing the reprocessing to IVS analysts, because correlators 

normally submit databases to IVS only once. 

Intensive sessions for determining UT1 were observed by the single baseline between TSUKUB32 

and WETTZELL nearly weekly from April through December, 2003. At each session, we took 5-7 

days to receive the data from WETTZELL and 1 day to complete the correlation processing and 

the primary solution. After the database was submitted to IVS, the final analysis were done at 

University of Bonn. We were confident that UT1 was determined with consistency by comparing 

our results to the WETTZELLKOKEE baseline. The WETTZELLKOKEE baseline is orthogonal to TSUKUB32-WETTZELL baseline and the intensive sessions of the WETTZELLKOKEE 

single baseline is being carried out 4 times a week with Mark 5 recording systems. The results 

of these two baselines generally agreed each other in each experiment even though two different 

recording systems were used. 

In the JADE experiments, no fringe had been detected on the baselines to SINTOTU3 in the 

GSI VLBI network since August, 2002. We tried to get to the reason for it in various ways and 

found that there was about -5 msec of gross time deviation on the local time system, which was 

caused by unlocking 1 pps signal in the GPS timing receiver. We tried to do fringe test with setting 

the stations’s clock offset -5.165 msec and finally succeed in fringe detection. Some of previous 

JADE experiments such as JADE0206 were reprocessed with the offset and new databases were 

resubmitted to IVS. 

In the intensive sessions, because of equipment failures, we lost the data of several sessions, 

which were not taken into account of 28 sessions. 

3. Global Solution 

The set of coordinates of GSI VLBI stations is to be a basis for defining the framework in the 

geodetic datum of Japan. However, the GSI VLBI stations except TSUKUB32 are not members 

in the major IVS network stations that the positions and velocities have been determined on 

a worldwide scale with global solutions using the CALC/SOLVE etc. The JADE experiments 

that these GSI VLBI local stations take an active role do not have the advantage of estimating 

EOP, because the baselines are not intercontinental. Consequently, the weights of these stations 

are set too low on the conventional global solutions on a regular basis such as for EOP. In this 

circumstances, we have approached to determine these local station position/velocity with few mm 

precision in our research activities in 2003. Preliminary results (Table 1) can be reviewed on the 

IVS 2003 Annual Report 137 
Tsukuba VLBI Correlator Geographical Survey Institute, Japan 

web (http://vldb.gsi.go.jp/sokuchi/vlbi/solutions/). 

Table 1. Station position with global solution by GSI 

I I I 

0.022 I 0.020 I 0.021 1 

4. Related Topics 

In the process of correlation and primary solution, we often found our station’s problems 

affected the quality of results such as clock breaks and unstable thermal environments. To improve 

the quality of data obtained from the stations, we checked the data each time after experiments 

and fed back the information to the stations each time when a defect occurred (Figure 2). 

We upgraded the management system of D1 tape, which was introduced in July 2002, with a 

handy barcode reader to reduce tape librarian’s burden. 

The geodetic department of GSI will be reorganized from April 2004. The GSI VLBI group 

will belong to a newly established space geodetic division. 

5. Staff 

0 K. Takashima : Operation manager (GSI). 

0 M. Machida : technical staff (GSI). 

0 M. Ishimoto : technical staff, intensive setups (GSI). 

~ 

138 IVS 2003 Annual Report 
Geographical Survey Institute, Japan Tsukuba VLBI Correlator 

0 S. Kurihara : technical staff, global solution analyst (GSI). 

0 K. Sakamoto : operator in charge of routine correlation processing (Space Engineering De0 T. Nishino : operator in charge of routine correlation processing (Space Engineering Develvelopment Co., Ltd). 

opment Co., Ltd). 

I Primary solution 

1 Global analysis 

Figure 2. Water-fall model for VLBI operations at GSI 

6. Plan for 2004 

From April 2004 to March 2005, GSI is planning 12 JADE experiments. Because GSI is shifting 

the recording system of GSI network stations toward the disk-based K-5 recording system in early 

2004, we will need a K-5 compatible correlation system to deal with the K-5 data at Tsukuba. 

We are considering to increase the number of UT1 intensive sessions in 2004. The sessions on 

Saturday will be observed with the K-4 recording system as usual. The weekday’s sessions are 

expected to be run by Mark 5/K-5. It seems that introducing the K-5 system to the Tsukuba 

VLBI Correlator would be useful in land surveying as well as in navigations with on-line data 

transfers. The current tape based correlator has the ability to process 3 baselines for 3 stations 

simultaneously. It could be still usable for JADE experiments to confirm the data by the K-5 

system. We are planning to expand it to process 6 baselines for 4 stations simultaneously for more 

efficient correlating processing. 

References 

[l] S. Kurihara, K. Takashima, T. Tanabe, H. Kawawa, K. Miyagawa: IVS Intensive VLBI Experiments 

for UT1 determination between Tsukuba and Wettzell, Journal of the Geographical Survey Institute 

2003 Vol. 102, 310, 2003.(in Japanese) 

IVS 2003 Annual Report 139 
Washington Correlator U. S. Naval Observatory 

Washington Correlator 

Kerry A. Kingham 

Abstract 

This report summarizes the activities of the Washington Correlator for the year 2003. The Washington Correlator provides 136 hours of processing per week, primarily supporting Earth Orientation 

and astrometric observations. In 2003 the major programs supported includes the IVS-R4, IVS-INT, 

IVS-R1, IVS-T and CRF. Four Mark 5 playbacks were added. 

1. Introduction 

The Washington Correlator (WACO) is located at and staffed by the U. S. Naval Observatory 

(USNO) in Washington, DC, USA. The correlator is sponsored and funded by the National Earth 

Orientation Service (NEOS) which is a joint effort of the USNO and NASA. Dedicated to processing 

geodetic and astrometric VLBI observations, the facility spent 100 percent of its time on these 

experiments. All of the weekly IVS-R4 sessions, all of the daily intensives, and several IVS-R1 

sessions were processed at WACO. The remaining time was spent on reference frame and astrometry 

sessions. The facility houses a Mark 4 Correlator. 

2. Correlator Operations 

The two Washington Correlator Mark 5P (prototype) units were upgraded to Mark 5As in 

April. Four additional Mark 5A playbacks were added in October. At the end of the year, the 

Washington Correlator had 6 Mark 5A playbacks on-line. The Correlator Facility also conditioned 

68 “A” 8-packs. 

During the year, the main theme was the increase in Mark 5 operational experience. By 

November, up to 4 stations in IVS experiments were recording with the Mark 5s using 8-packs of 

various sizes. The Intensives continued to use single disks and celebrated the first full year of Mark 

5 Intensives in November. The increase in the use of Mark 5 for recordings had a direct impact on 

the processing factors. Due to the “perfect” playback, lack of tape positioning, and the need for 

less operator intervention, the average processing factor dropped from 3.9 to 1.5. Unfortunately, 

this will not allow more experiments to be processed by the correlator because staff shortages will 

prohibit setup and review. 

The correlator facility operates 136 hours per week, and is fully loaded at this level. 

Table 1 lists the experiments processed during 2003. 

3. Staff 

The Washington Correlator is under the management and scientific direction of the Earth 

Orientation Department of the U.S. Naval Observatory. USNO personnel continue to be responsible 

for overseeing the scheduling and processing. During the period covered by this report, a private 

contractor, NVI, Inc., supplied a contract manager and correlator operators. Table 2 lists staff 

and their duties. 

~ 

140 IVS 2003 Annual Report 
I 

t 

U. S. Naval Observatory Washington Correlator _._. 

52 

1 

14 

6 

3 

3 

3 

3 

5 

200 

Table 1. Experiments processed during 2003 

NS-R4 experiments 

CONT 

CRF (Celestial Reference F’rame) 

APSG (Asia Pacific) 

OHIGGINS 

R&D 

SURVEY 

IVS-T (Terrestrial Reference Frame) 

IVS-R1 

Intensives 

Staff 

Dr. Kerry Kingham (USNO) 

Bruce Thornton (NVI) 

Harvis Macon (NVI) 

Roxanne Watkins (NVI) 

Dwayne Sneed (NVI) 

Joseph Granderson (NVI) 

Kenneth Potts (NVI) 

Steven Springer (NVI) 

Lawrence Dorsey (NVI) 

Valerie Bockarie (NVI) 

Table 2. Sa 

Duties 

VLBI Correlator Project Scientist, 

responsible for the scientific integrity of correlated data, 

hardware and software maintenance and upgrades, 

and computer system administration. 

Also responsible for process scheduling and 

evaluation of correlated data. Overseea session 

setups and prepasses and evaluates station performance. 

Operations Manager, 

responsible for correlator operator scheduling, 

daily operations, and tape shipping. 

Intensive processing and review. 

Lead Correlator operator, 

NEOS-A and Intensive setups. 

Tape Librarian 

Correlator Operator 

Correlator Operator 

Correlator Operator 

Part-time Correlator Operator 

Part-time Correlator Operator 

Part-time Correlator Operator 

4. Outlook 

The Washington Correlator expects to add more Mark 5 playback units to the correlator in 

the next year. The increased use of Mark 5 should increase the efficiency and and quality of the 

processing. 

IVS 2003 Annud 141 

Bundesamt fiir Kartographie und Geodiisie BKG Data Center 

BKG Data Center 

Volkmar Thorandt, Reiner Wojdziak 

Abstract 

This report summarizes the activities and background information of the IVS Data Center for the 

year 2003. Included are information about functions, structure, technical equipment and staff members 

of the BKG Data Center. 

1. BKG Data Center Functions 

The BKG (Federal Agency for Cartography and Geodesy) Data Center is one of the three IVS 

Primary Data Centers. It archives all VLBI related data of IVS components and provides public 

access for the community. The BKG Data Center is connected to the OPAR and CDDIS Data 

Centers by mirroring the OPAR and the CDDIS file stocks several times per day. The following 

sketch shows the principle of mirroring: 

GSFC 

Figure 1. Principle of mirroring 

IVS components can choose one of these Data Centers to put their data into the IVS network 

by using its incoming area which each of them has at its disposal. The BKG incoming area is 

protected and the users need to obtain username and password to get access (please contact the 

Data Center staE). 

An incoming script is watching this incoming area and checking the syntax of the files sent by 

IVS components. If it is 0.k. the script moves the files into the data center directories; otherwise 

the files will be sent to a badfile area. Furthermore the incoming script informs the responsible 

st& at Data Center by sending +mails about its activities. The incoming script is part of a 

technological unit which is responsible for managing the IVS and the Operational Data Center 

and to carry out first analysis steps in an automatic manner. All activities are monitored to 

IVS 2003 Annual Report 145 
BKG Data Center Bundesamt fiir Kartographie und Geodkie 

guarantee data consistency and to control all analysis steps from data incoming to delivering of 

analysis products to IVS. 

Public access to the BKG Data Center is available through FTP: 

ftp. leipzig . if ag.de 

uid: anonymous 

pw: e-mail address 

cd vlbi 

respectively 

WWW: http://uuu.leipzig.ifag.de/VLBI 

Structure of BKG IVS Data Center: 

vlbi/ 

ivs-ierd 

ivs-pilot 2000/ 

ivs-pilot 2001/ 

ivs-pi lot bl/ 

ivs-pilottro/ 

ivscontrol/ 

ivsdat a/ 

ivsdocument s/ 

ivsproduc t s/ 

: root directory 

: VLBI products for IERS 

: directory for special investigations 

: directory for special investigations 

: directory for baseline time series 

: directory for tropospheric time series 

: controlfiles for the data center 

: VLBI observation files 

: IVS documents 

: analysis products 

(earth orientation, terrestrial and celestial frames, 

troposphere) 

2. Technical Equipment 

HP Workstation (HP UX 10.20 operating system) and Linux Server 

disk space: 190 GBytes (Raid system) 

internet rate: 34 MBit/sec 

backup: automatic tape library 

3. StafF Members 

Volkmar Thorandt (coordination, data analysis, data center, volkmar.thorandt@bkg.bund.de) 

Reiner Wojdziak (data center, web design, reiner.wojdziak@bkg.bund.de) 

Dieter Ullrich (data analysis, data center, dieter.ullrich@bkg.bund.de) 

Gerald Engelhard t (data analysis, gerald .engelhard t 63 bkg. bund.de) 

146 IVS 2003 Annual Report 
Kashima . Space Research Center, Communications -. Research Laboratory Data Center at CRL 

IVS 2003 Annual Report 147 

Data Center at Communications Research Laboratory 

Yasuhiro Koyama 

Abstract 

The Data Center at Communications Research Laboratory archives and releases the databases 

and analysis results processed at the Correlation Center and the Analysis Center at Communications 

Research Laboratory. Regular VLBI sessions with the Key Stone Project VLBI Network were the 

primary objects of the Data Center. These regular sessions continued until the end of November 2001. 

In addition to the Key Stone Project VLBI sessions, Communications Research Laboratory has been 

conducting geodetic VLBI sessions for various purposes and these data are also archived and released 

by the Data Center. 

1. Introduction 

The IVS Data Center at the Communications hearch Laboratory (CRL) archives and releases 

the databases and analysis results processed by the Correlation Center and Analysis Center at 

CRL. Major parts of the data are from the Key Stone Project (KSP) VLBI sessions [l] but other 

regional and international VLBI sessions conducted by CRL are also archived and released. Since 

routine observations of the KSP network terminated in the end of November 2001, there were no 

additional data for the KSP regular sessions since 2002. In 2003, thrw geodetic VLBI sessions were 

carried out and processed. The analysis results in the SINEX (Solution Independent Exchange) file 

format and other form of data formats are available from the WWW and FTP servers. Database 

files generated with the Mark I11 database file format are available upon request and will be sent 

to the users in DDS tape cartridges. Database files of non-KSP sessions, i.e. other domestic and 

international geodetic VLBI sessions, are also available from the FTP server. Table 1 shows the 

list of WWW and FTP server systems maintained by the Data Center at CRL. 

Table 1. URL of the WWW and FTP server systems. 

Service UFU 

KSP WWW pages http://ksp.crl.go.jp/ 

IVS WWW mirror pages 

FTP ftp://ftp.crl.go.jp/pub/dk/ivs/ 

http : //ivs . crl .go. jp/mirror/ 

The maintenance of these server machines has been moved from the VLBI research group of 

the CRL to the common division for the institutional network service of the laboratory in 2001 to 

improve the network security of these systems. 

2. Data Products 

2.1. KSP VLBI Sessions 

The KSP VLBI sessions were performed with four KSP IVS Network Stations at Kashima, 

Koganei, Miura, and 'lhteyama on a daily or bi-daily (once every two days) basis until May 1999. 
Data Center at CRL Kashima Space Research Center, Communications Research Laboratory 

The duration of each session was about 23.5 hours. Within the period, daily observations were 

performed from March 1 until April 1, 1999 to obtain continuous VLBI data series for various 

investigations such as studies about the atmospheric delay models and for the improvements of 

the data analysis technique. The high-speed ATM (Asynchronous Transfer Mode) network line 

to the Miura station became unavailable in May 1999 and real-time VLBI observations with the 

Miura station became impossible. After this time, the real-time VLBI sessions were performed 

with three stations at Kashima, Koganei, and Tateyama. Once every six days (every third session), 

the observed data were recorded to the K4 data recorders at three stations and the Miura station 

participated in the sessions with the tape-based VLBI technique. In this case, the observed data 

at three stations except for the Miura station were processed in real-time and the analysis results 

were released promptly after the observations completed. A day later, the observed tapes were 

transported from Kashima, Miura, and Tateyama stations to Koganei station for tape-base correlation processing of the full six baselines. After the tape-base correlation processing completed, 

the data set produced with the real-time VLBI data processing was replaced by the new data set. 

In July 2000, unusual site motion of the Tateyama station was detected from the KSP VLBI 

data series, and the frequency of the sessions was increased from bi-daily to daily since July 22, 

2000. The daily sessions were continued until November 11, 2000, and the site motion of the 

Tateyama and Miura stations were monitored in detail. During the period, it was found that 

Tateyama station moved about 5 cm to the northeast direction. Miura station also moved about 3 

cm to the north. The unusual site motions of these two stations gradually settled and the current 

site velocities seems to be almost the same as the site velocities before June 2000. By investigating 

the time series of the site positions, the unusual site motion started from sometime between the 

end of June 2000 and the beginning of July 2000. At the same time, volcanic and seismic activities 

near the Miyakejima and Kozushima Islands began. These activities are believed to have caused 

the regional crustal deformation near the area, and the unusual site motions at Tateyama and 

Miura are explained by the event. 

2.2. Other VLBI sessions 

In addition to the KSP regular VLBI sessions, domestic and international geodetic VLBI 

sessions have been conducted by CRL in cooperation with Geographical Survey Institute (GSI) 

and other organizations. These sessions are listed in Table 2. The observed tapes of these sessions 

were correlated by using the K-4 correlator and the software correlation programs (K-5 correlator) 

at CRL either at Koganei or at Kashima. 

In 2003, two e-VLBI sessions (evlbi4 and tsev6) were performed for two hours each with 

Kashima 34m and Westford stations with cooperation with Haystack Observatory. The purpose 

of these experiments were to demonstrate rapid turnaround processing of the international VLBI 

observations by using e-VLBI technique. Especially, we have demonstrated that the UT1-UTC 

can be estimated within one day from the observations from the session tsev6 performed on June 

27, 2003 [2]. Two K5 test session, i.e. U03031 and JD0306, were performed to evaluate the performance of the newly developed K5 VLBI system and Gigabit VLBI system. In the U03031 session, 

the K5 VLBI system and the Gigabit VLBI system were used in parallel with the K4 VLBI system at Kashima 11-m and Koganei 11-m stations. On the other hand, the JD0306 is one of the 

routine domestic VLBI sessions coordinated by the Geographical Survey Institute. Kashima 11-m, 

Tomakomai 11-m, Gifu 11-m, and Yamaguchi 32-m stations participated in the JD0306 session in 

148 IVS 2003 Annual Report 
Kashima Space Fksearch Center, Communications Research Laboratory Data Center at CFU 

Table 2. Geodetic VLBI sessions conducted by CFU 

Year exp. names sessions 

1999 K4 Tie K4TIE1, K4TIE2 

2000 Japan Tie JPNTI2, JPNTI3, JPNTI4, JPNTI5, JPNTI6 

GIFT GIFT01 , GIFT02 

2001 Japan Tie JPNTI7 

HOKT HOKTOl 

2002 HOKT HOKT02 

CUTE CUTEO1, CUTEO2, CUTIN3 

Usuda USUDAl 

2003 CUTE CUTE04 

K5 Test U03031, JD0306 

e-VLBI evlbi4, tsev6 

Nozomi 34 sessions 

Havabusa 10 sessions 

addition to the regular GSI VLBI sites at Tsukuba 32-m, Chichijima 11-m, and Aira 11-m. K5 

VLBI system was used at five stations and Gigabit VLBI system was used at two stations. Results 

from different VLBI systems were compared and it was confirmed that the K5 VLBI system and 

Gigabit VLBI system have expected performance [3]. 

Figure 1 show the number of geodetic VLBI sessions and number of did observed delays used 

in the data analysis for each year. 

Figure 1. Number of sessions (left) and observed delays (right) used in the data analysis for each year up 

to the year 2003. 

3. F’uturePlans 

Although the regular VLBI sessions with the KSP VLBI network finished in 2001, the IVS 

Data Center at CRL will continue its service and will archive and release the analysis results 

IVS 2003 Annual Report 149 I 

I 
Data Center at CRL Kashima Space Research Center, Communications Research Laboratory 

accumulated by the Correlation Center and Analysis Center at CRL. In addition, a number of 

VLBI sessions are planned to be conducted in the year 2004 and these data will be archived and 

released to the public users. 

In April 2004, Communications Research Laboratory will be integrated with the Telecommunications Advanced Organization of Japan (TAO) and the new institute will be established. The 

name of the institute will be National Institute of Information and Communications Technology 

and the VLBI activities in the CRL will be continued under the new institute. 

References 

[l] Special issue for the Key Stone Project, J. Commun. Res. Lab., Vol. 46, No. 1, March 1999 

[2] Yasuhiro Koyama, Tetsuro Kondo, Hiro Osaki, Alan R. Whitney and Kevin A. Dudevoir, Rapid Turn 

Around EOP Measurements by VLBI over the Internet, Proceedings of the XXIII General Assembly 

of the International Union of Geodesy and Geophysics (June 30-July 11, 2003, Sapporo, Japan) (in 

press) 

[3] Koyama, Y., T. Kondo, H. Osaki, K. Takashima, K. Sorai, H. Takaba, and K. F’ujisawa, IVS CRL 

TDC News, No. 23, Nov. 2003, pp. 26-30 

150 IVS 2003 Annual Report 
NASA Goddard Space Flight Center CDDIS Data Center 

IVS 2003 Annual Report 151 

CDDIS Data Center Summary for the 2003 IVS Annual Report 

Carey No11 

Abstract 

This report summarizes activities during the year 2003 and future plans of the Crustal Dynamics 

Data Information System (CDDIS) with respect to the International VLBI Service for Geodesy and 

Astrometry (IVS). Included in this report are background information about the CDDIS, the computer 

architecture, staffing supporting the system, archive contents, and future plans for the CDDIS within 

the IVS. 

1. Introduction 

The Crustal Dynamics Data Information System (CDDIS) has supported the archive and 

distribution of Very Long Baseline Interferometry (VLBI) data since its inception in 1982. The 

CDDIS is a central facility providing users access to raw and analyzed data to facilitate scientific 

investigation. A large portion of the CDDIS holdings of GPS, GLONASS, laser ranging, VLBI, 

and DOFUS data are stored on-line for remote access. Information about the system is available 

via the web at the URL http://cddisa.gsfc.nasa.gov. The current and future plans for the system’s 

support of the IVS are discussed below. 

2. System Description 

The CDDIS archive of VLBI data and products are accessible to the public via anonymous ftp 

access. 

2.1. Computer Architecture 

The CDDIS is operational on a dedicated UNIX server which has over 540 Gbytes of on-line 

magnetic disk storage (470 Gbytes in RAID storage); approximately 25 Gbytes are devoted to 

VLBI activities. The CDDIS is located at NASA GSFC and is accessible to users 24 hours per 

day, seven days per week. 

2.2. Staffing 

supports all CDDIS activities (see Table 1 below). 

Currently, a staff consisting of one NASA civil service employee and 2.5 contractor employees 

3. Archive Content 

The CDDIS has supported GSFC VLBI coordination and analysis activities for the past several 

years through an on-line archive of schedule files, experiment logs, and data bases in several formats. 

This archive has been expanded for the IVS archiving requirements. 

The IVS data center content and structure is shown in Table 2 below (a figure illustrating 

the flow of information, data, and products between the various IVS components was presented 

in the CDDIS submission for the 2000 TVS annual report). In brief, an incoming data area has 
CDDIS Data Center NASA Goddard Space Flight Center 

Name 

Ms. Carey No11 

Table 1. CDDIS Staff 

Posit ion 

CDDIS Manager 

Dr. Maurice Dube 

Ms. Ruth Kennard 

Ms. Laurie Batchelor 

Head, CDDIS contractor staff and senior programmer 

Request coordinator 

Data technician (part-time) 

been established on the CDDIS host computer, cddisa.gsfc.nasa.gov. Operations and analysis 

centers deposit data files and analyzed results using specified file names to appropriate directories 

within this filesystem. Automated archiving routines, developed by GSFC VLBI staff, peruse the 

directories and migrate any new data to the appropriate public disk area. These routines migrate 

the data based on the file name to the appropriate directory as described in Table 2. Index files 

in the main subdirectories under ftp://cddisa.gsfc.nasa.gov/pub/vlbi are updated to reflect data 

archived in the filesystem. Furthermore, mirroring software has been installed on the CDDIS host 

computer, as well as all other IVS data centers, to facilitate equalization of data and product 

holdings among these data centers. At this time, mirroring is performed between the IVS data 

centers located at the CDDIS, the Bundesamt fr Kartographie und Geodsie in Leipzig, and the 

Observatoire de Paris. 

The public filesystem in Table 2 on the CDDIS computer, accessible via anonymous ftp, consists 

of a data area, which includes auxiliary files (e-g., experiment schedule information, session logs, 

etc.) and VLBI data (in both data base and NGS card image formats). A products disk area has 

also been established to house analysis products from the individual IVS analysis centers as well 

as the official combined IVS products. A documents disk area contains format, software, and other 

descriptive files. 

4. Data Access 

During 2003, over 100 user organizations accessed the CDDIS on a regular basis to retrieve 

VLBI related files. Nearly 17K VLBI-related files were downloaded per month from the archive. 

5. Future Plans 

The CDDIS staff will continue to work closely with the IVS Coordinating Center staff to ensure 

that our system is an active and successful participant in the IVS archiving effort. A new Linux 

server was procured in 2002; additional RAID disks and a dedicated DLT tape backup system 

were also purchased. The CDDIS staff plans to make this new system operational by the end of 

2003. 

152 IVS 2003 Annual Report 
NASA Goddard Space Flight Center CDDIS Data Center 

vlbi/ ivsdat a/db / y yy y 

vlbi/ivsdata/ngs/ y yyy 

vlbi/ivsdata/aux/yyyy/ssssss 

Table 2. XVS Data and Product Directory Structure 

VLBI data base files for year yyyy 

VLBI data files in NGS card image format for year 

YYYY 

Auxillary files for year yyyy and se ssion ssssss; these 

files include: log files, wx files, cable files, schedule 

vlbi/ivsdocuments 

I files, corre1ator notes 

Product Directories 

IVS document files (solution descriptions, etc.) 

vlbi/ivsproducts/crf 

vlbi / ivsproducts/eopi 

vlbi/ivsproducts/eops 

vlbi/ivsproducts/ trf 

vlbi/ivsproducts/trop 

vlbi / ivsproduc ts / ivs-iers 

vlbi/ivsproducts/ivs-pilot 2000 

vlbi / ivsproduct s / ivs-pilot200 1 

vlbi/ivsproducts/ivs-pilotbl 

CRF solutions 

EOP-I solutions 

EOP-S solutions 

TRF solutions 

Troposphere solutions 

IVS contributions to the IERS 

IVS Analysis Center pilot project (2000) 

IVS Analysis Center pilot project (2001) 

IVS Analysis Center pilot project (baseline) 

IVS Analysis Center pilot project (troposphere) 

IVS 2003 Annual Report 153 
Italy CNR Data Center Istituto di Radioastronomia-Bologna 

Italy CNR Data Center Report 

M. Negusini 

Abstract 

This report summarizes the situation of the Italy CNR VLBI data center. It will give fundamental 

information about the structure of the center, its locations, and its activities. 

1. Introduction 

The Italy CNR VLBI data center is the joint effort of: 

a) the Istituto di Radioastronomia (Institute of Radio Astronomy IRA) of the Consiglio 

Nazionale delle Ricerche (CNR) located in Bologna, where the research activity is carried out, 

both in radio astronomy and geodesy, and the two VLBI antennas in Medicina (near Bologna) and 

Noto (in Sicily) are managed, 

b) and in its section located in Matera at the Center of Spatial Geodesy (of the Italian Space 

Agency), where the main research activity in geodesy is carried out, and a VLBI antenna, a laser 

ranging telescope, a permanent GPS receiver and a PRARE antenna are located. 

At the moment, the main analysis activity and storage is concentrated in Matera, where we 

store and analyze single databases, using CALC/SOLVE software. We are using f-solve regularly 

updated. The IRA has started to store VLBI geodetic databases from 1989, but the databases 

archived in Bologna mostly contain data including European antennas, starting fiom 1987. In particular most of the databases present here have VLBI data with at least three European antennas. 

However we are also storing all the databases with the Ny-Alesund antenna data. During 2002 

and 2003, we have stored in Matera all the 2000-2003 databases available on the IVS data centers. 

All the databases have been processed and saved with the best selection of the parameters for the 

final arc solutions. 

In some cases we have introduced the wet delay coming from GPS into the European databases 

(at present only for EUROPE experiments for the years 1998 and 1999), as if it was produced by 

a WVR. Also these databases are available and stored with a different code from the original 

databases. For this we have produced a modified version of DBCAL, available to external users. 

In Matera we have stored part of the databases and all the superfiles and we are performing 

there global solutions, too. 

2. Computer Availability and Routing Access 

In Bologna the main computer is a HP 785/B2600 workstation. The internet address of this 

computer is boira3.ira.cnr.it and the databases are stored in different directories and in different 

disks as well. The complete list of directories where databases are stored is the following: 

1 = /datal/mk3/datal 

2 = /datal/mk3/data2 

4 = /data6/dbase6 

6 = /data5/dbase5 

5 = /data4/dbase4 

154 IVS 2003 Annual Report 
Istituto di Radioastronomia-Bologna Italy CNR Data Center 

7 = /data7/dbase7 

8 = /data8/dbase8 

9 = /data9/dbase9 

10= /geo/data 

11= /geo/1999 

12= /geo/2000 

The username for accessing the database at the moment is geo. The password can be requested 

by sending an e-mail to tomasi@ira.cnr.it. 

In Matera the main computer is an Hp282 computer with internet name hpj.itis.mt.cnr.it. 

The databases are stored in different directories and the full list follows: 

1 = /datal/mk3/datal 

2 = /datal/mk3/data2 

6 = /data5/dbase5 

5 = /data4/dbase4 

7 = /data8/dbase8 

8 = /datalO/dbaselO 

9 = /datal3/dbasel3 

10 = /datal4/dbasel4 

/data2/super 

/datalO/super 10 

/data9/super9 

/data8/super8 

The super files are stored in different directories: 

The list of superfiles is stored in the file /data6/solve_files/SUPCAT. The area for data storage 

has been enlarged to 250 gigabytes with the installation of a new server. The data can be accessed 

using the username geo, and the password can be requested from tomasi@ira.cnr.it. 

IVS 2003 Annual Report 155 
Paris Observatory (OPAR) Data Center Observatoire de Paris, SYRTE/UMR 8630 

Paris Observatory (OPAR) Data Center 

Najat Essai'fi 

Abstract 

This report summarizes the OPAR Data Center activities over 2003. Included are informations 

about functions, architecture, status, future plans and staff members of OPAR Data Center. 

1. OPAR Data Center Functions 

The Paris Observatory (OPAR) has provided since 1999 a Data Center for the International 

VLBI Service for Geodesy and Astrometry (IVS). The OPAR as well as CDDISA and BKG is 

one of the three IVS Primary Data Centers. Their activities are done in close collaboration for 

collecting files (data and analysis files), and making them available to the community as soon as 

they are submitted. 

The three data centers have a common protocol and each of them : 

0 has the same directory structure (with the same control file), 

0 has the same script, 

0 is able to receive all IVS files (auxilliary, database, products, documents), 

0 mirrors the other ones every three hours, 

0 gives free FTP access to the files. 

CDDIS 

(USA) 

I i 

& L 

I 

OPAR 

I 

(FRANCE) 

I 

7 I 

7 

This protocol gives the IVS community a transparent access to a data center through the same 

directory, and a permanent access to files in case of a data center breakdown. 

2. Architecture 

To be able to put a file in a Data Center, operational and analysis centers have to be registered 

by the IVS Coordinating Center. The file names have to conform to the name conventions. A script 

156 IVS 2003 Annual Report 
Observatoire de Paris, SYRTE/UMR 8630 Paris Observatory (OPAR) Data Center 

checks the file and puts it in the right directory. The script undergoes permanent improvement 

and takes into account the IVS components’ requests. 

The structure of IVS Data Centers has evolved since 2002, one primary directory has been 

added: 

ivscontrol/ 

ivsdocument s/ 

ivsdat a/ 

a=/ 

db/ 

w/ 

sinex/ 

ivsproducts/ 

eopi/ 

cops/ 

crf / 

trf/ 

daily-sinex/ 

ivs-iers/ 

ivs-pilot2000/ 

ivs-pilot2001/ 

ivs-pilottro/ 

ivs-pilotbl/ 

: provides the control files needed by the data center 

(session code, station code, solution code. . . : provides documents and descriptions about IVS products 

: provides files related to the observations: 

: 

: observation files in data-base CALC format 

: observation files in NGS format 

: observation files in SINEX format 

: provides results from Analysis Center: 

: Earth Orientation Parameters, intensive sessions 

: Earth Orientation Parameters, sessions of 24h 

: Celestial Reference Frame 

: Terrestrial Reference Frame 

: Time series solutions in SINEX format of Earth 

: provides products for IERS Annual Report 

: provides products of 2000 for special investigations 

: provides products of 2001 for special investigations 

: provides tropospheric time series 

: provides baselines files 

awtilliary files (schedule, log.. .) 

orientation and site positions 

3. Current Status 

The OPAR data center is operated actually on a PC located at Paris Observatory, and running 

the Linux red hat 8.0 operating system. To make all IVS products available on-line, the disk 

storage capacity was significantly increased and the server is equipped now with a 120 Gb disc 

storage for VLBI activities. 

The OPAR server is accessible 24 hours per day, seven days per week through Internet connection with 2Mbit/s rate. Users can get the IVS products by using the FTP protocol. Access to 

this server is kee for users. 

FTP access: 

ivsopar .obspm.fr 

username : anonymous 

password : your +mail 

cd vlbi (IVS directory) 

4. Futureplans 

The OPAR staff will continue to work with the IVS community and in close collaboration with 

the two others Primary Data Centers in order to provide public access to all VLBI related data. 

IVS 2003 Annual Report 157 
Paris Observatory (OPAR) Data Center Observatoire de Paris, SYFtTE/UMR 8630 

To ensure better access to the OPAR Data Center the staff is studying Some computer system 

enhancements, including a RAID disk system. 

5. StafF Members 

Staff members who are contributing to Data Center and OPAR Analysis for IVS are listed 

0 Najat Essaifi, Data Base manager. 

0 Anne-Marie Gontier, responsible for GLORIA analysis software. 

0 Martine Feissel, scientific developments. 

0 Daniel Gambis, interface with IERS activities. 

below : 

6. Contact Information 

To obtain informations about the OPAR data center please contact : 

Najat Essaifi 

Observatoire de PARIS 

61, Avenue de l’observatoire 

75014 Paris - FRANCE 

Phone : 33 1 40 51 22 33 

Fax : 33 140 51 22 91 

E-mail : essaifi@hpvlbi.obspm.fr 

158 IVS 2003 Annual Report 

Sobolev Astronomical Institute of St. Petersburg University Saint-Petersburg University Analysis Center 

Analysis Center of Saint-Petersburg University 

Maria Kudryasbova 

Abstract 

This report briefly summarized the activity of the Analysis Center of Saint Petersburg University 

during 2003. Changes which happened in our solution and staff are described. 

IVS 2003 Annual Report 161 

1. Introduction 

Analysis Center of Saint Petersburg University is involved in processing of intensive sessions 

from 1998. Since 2000 it also derives Earth Orientation Parameters (x,y coordinates of pole, UT1- 

UTC, nutation offsets) by processing NEOS-A, R1, R4 sessions. OCCAM software is used in the 

Analysis center in order to obtain our solutions. Unfortunately, this year our solution have not be 

included in combined IVS solution due to some problems which we had with Terrestrial Reference 

Frame. 

2. Staff 

This year a new member was involved in the process of data handling. 

Veniamin Vityazev - Director of Astronomical Institute of Saint-Petersburg University, PhD., 

Maria Kudryashova - Research assistant of Astronomical Institute of Saint-Petersburg UniverJulia Sokolova - Student of Saint-Petersburg University. Processing of VLBI data. 

Prof. General coordination and support of activity at the Astronomical Institute. 

sity. Processing of VLBI data. 

3. Description of Solutions 

Currently we continue to contribute UT1-UTC values obtained by processing Intl observational program. Our time series (spuoooO2.eopi) contains 1161 estimates since Sept. 1, 1997. All 

estimated parameters (UT1-UTC, offset for wet delay, offsets and rates of station clocks) have been 

adjusted using least square technique. Troposphere gradients were not estimated in this solution. 

The MBH2000 nutation model is used as a priori one. 

Also, we continued processing of 24hour session in order to compute five EOP. In March, 2003 

name of our solution spuoooO2.eops which contained all 24hour VLBI sessions since 1994 have 

been changed to spu0002i.eops. This change has been done in order to distinguish this time series 

from our new solution spu0002m.eops. The only difference between this time series is an a priory 

nutation model. To compute spu0002m.eops we applied MBH 2000 model. As for spuOOO2i.eops 

time series, IAU 1980 nutation model have been used. Detailed description of analysis strategy 

and estimated parameters is given in [l]. OCCAM software v.5.0 have been used for obtaining 

these solutions. 

The EOP time series spuOOO2i.eops was replaced by series spuOOO3i.eops in Aug, 2003. There 

are few differences between the solutions. In order to obtain spuOOO3i.eops new version of OCCAM 

package v.5.1 is used. This version of the software allows us to estimate corrections for station 
Saint-Petersburg University Analysis Center Sobolev Astronomical Institute of St. Petersburg University 

spu0002i.eops 

OCCAM version 5.0 

TRF fixed to ITRF2000 

time span Jan., 1994 - Aug., 2003 

number of sessin 545 

coordinates under NNR and NNT conditions. Some stations (for instance, Tigoconc) have unstable coordinates so we estimate their location for every session in which this station takes part. 

Also, new Terrestrial Reference Frame (VTRF 2003, see [2]) was implemented for computation 

spuOOO3i.eops. 915 NEOS-A, R1 and R4 sessions with about 24-hour measurements duration were 

analyzed in order to calculate spu0003i.eops. This series covers time span between Jan. 1, 1989 

and 31 Dec., 2003. 

All parameters have been adjusted using Kalman filter technique. Troposphere gradients are 

treated as a constant parameters. Main differences between this two series are summarized in the 

table 1 for clarity. 

spu0003i.eops 

5.1 

not fixed. VTRF'2003 is used as a priory TRF 

Jan., 1989 -now 

915 

I ~~ 

trop.grad 1 estimated as stoch.param. I estimated as constant param. 

References 

[l] Kudryashova, M., Vityazev, V., Analysis center of St. Petersburg University In: International VLBI 

Service for Geodesy and Astrometry 2002 Annual Report, NASA/TP-2003-211619, N. R. Vandenberg 

and K. D. Baver (eds.), 221-224, 2002. 

[2] Nothnagel, A., VTRF2003: a conventional VLBI Terrestrial Reference Frame, available at 

http: / /giub .geod.uni-bonn .de/vlbi/IVS- AC /vtrf2003/vtrf2003 .html 

162 IVS 2003 Annual Report 
Geoscience Australia Geoscience Australia Analysis Center 

Geoscience Australia Analysis Center 

Oleg Titov, Ramesh Govind, Clement Ogaja 

Abstract 

This report gives an odew about activity of the Geoscience Australia IVS Analysis Center during 

the 2003 year. 

1. General Informat ion 

The Geoscience Australia IVS Analysis Center is located in Canberra. In 2003 the Center 

physically moved to new location in Symonston building. At the new structure the Space Geodesy 

Analysis Center became a part of Minerals and Geohazard Division. 

2. Component Description 

Currently the GA IVS Analysis Center contributes five EOPs for IVS-R1 and IVS-R4 networks. 

The EOP time series from 1983 to 2003 are available. Also the CRF catalogues using a global set 

of VLBI data from 1980 to 2003 are regularly submitted. 

3. Staff 

0 Dr. hesh Govind - Director of the Space Geodesy Analysis Center 

0 Dr. Oleg Titov - project officer 

0 Dr. Clement Ogaja - project officer 

4. Current Status and Activities 

Global homogeneous solution has been done using the new facilities of OCCAM. VLBI data 

comprising 2985 daily sessions from 12-Apr-1980 till 13-Oct-2003 have been used to compute the 

global solution AUS2003b. This includes 2,707,712 observational delays from 645 radiosources 

observed by 58 VLBI stations. Weighted root-mean-square of the solution is about 0.645 cm 

(about 21 picosec). 

Using the "R approach all radiosource coordinates were estimated as global parameters without separation into stable and unstable ones. Station coordinates were also estimated using "Ft 

and NNT constraints. The long-term time series of the station coordinates have been established 

to estimate the corresponding velocities for each station. Due to a limited amount of observations 

the velocities have been estimated for 52 stations only. 

New version of the OCCAM (v6.0) software is being prepared in collaboration with scientists 

from Vienna (Technical University of Vienna), Munich (DGFI) and Saint-Petersburg (IAA). It 

will include updated system of reductions, three adjustment methods, latest advanced mapping 

functions, etc. 

Also the GA Analysis Center continues the regular submission of EOPs to the IVS/IERS and 

IVS 2003 Annual Report 163 
Geoscience Australia Analysis Center Geoscience Australia 

works on the development of long-term time series for the EOP, station coordinates and comparison 

of techniques (VLBI, SLR, GPS) for EOP and ITRF adjustment. 

Long-term comparison of results from co-located VLBI, GPS and SLR stations contributing 

to the IVS, IGS, ILRS have been carried out to assess the consistency between the techniques. 

Seasonal variations of baseline lengths as well as individual site radial components were considered 

over long time periods. Spectral analysis of the baseline time series revealed the existence of both 

annual and semiannual terms. The estimates of the signal amplitudes and phases as well as relative 

rates were computed for 19 independent co-located baselines and cross-validated (Fig.1). 

A subsequent estimation was done to determine the seasonal effects at the individual sites. For 

instance, the annual terms indicated that the northern hemisphere sites rise in the first part of 

the year and lower in the second part (Fig.2). Similarly, it was shown that sites in the southern 

hemisphere are lowered in the first part of the year (Fig.3). 

14 1 

I 12 VLBl 

** 

0 

- 

10 0 GPS 

A SLR 

-8 

-Linear ~LBI) 

-Linear (GPS) $6 

4 

2 

0 

0 5000 10000 15000 

Baselength [km] 

Figure 1. Amplitude vs baseline length of annual signature for 19 baselines from cdocated sites. 

5. Future Plans 

0 comparison of the individual ICRF solutions available through the IVS website 

0 combined estimation of the EOPs using VLBI, SLR and GPS data 

0 cooperation with the Australian National University (ANU), Australian National Telescope 

Facility (ANTF) and University of Tasmania on development of VLBI for the southern 

hemisphere 

164 IVS 2003 Annual Report 
Geoscience Australia Geoscience Australia Analysis Center 

- 

E 

L 

E 

f 

Q: 

10 

5 

0 

-5 

-10 I I I 

0 0.2 0.4 0.6 0.8 1 1.2 

Epoch bad 

Figure 2. Annual signatures from co-located sites at Matera. 

15 

10 

- 

E5 

3 -5 

0 L 

u 

-10 

-15 

-20 ! I I I I I I 

0 0.2 0.4 0.6 0.8 1 1.2 

Epoch baa 

Figure 3. AMU~ signatures from cdocated sites at Hobart. 

~ 

IVS 2003 Annual Report 165 
Bordeaux Observatory Analysis Center Observatoire de Bordeaux 

Bordeaux Observatory Analysis Center Report 

Patrick Charlot, Antoine Bellanger, Alain Baudry 

Abstract 

This report summarizes the activities of the Bordeaux Observatory Analysis Center during the 

year 2003. On the analysis side, we have completed processing of five years of NEOS-A/IVS-R4 data 

(1999-2003) and obtained preliminary results for the temporal evolution of the source positions over 

this period. On the research side, our major achievements include the organisation and scheduling of 

a third experiment as part of our ICRF densification project in the northern sky, and evaluation of 

astrometric suitability for additional sources at S, X, K and Q bands. Plans for the year 2004 follow 

the same analysis and research lines. 

1. General Information 

The Bordeaux Observatory Analysis Center is located in Floirac, near the city of Bordeaux, 

in the southwest of France. It is funded by the University of Bordeaux and the CNRS (National 

Center for Scientific Research). 

Our work is focused on the maintenance, extension, and improvement of the celestial reference 

frame. In particular, we lead an observing program on the European VLBI Network (EVN) to 

densify the International Celestial Reference Frame (ICRF) [l] and conduct research related to the 

effect of source structure in geodetic VLBI data [2]. Additionally, we develop routine analyses of 

IVS data with the aim of studying the ICRF source position stability and the physical phenomena 

that can affect this stability. 

VLBI analyses are conducted with the MODEST software, developed and maintained by the 

Jet Propulsion Laboratory [3]. It is installed on a Compaq DS20 workstation along with the AIPS 

and DIFMAP imaging software. 

As a result of reorganisation of the University network, the Observatory www address and all 

email adresses for people at the Observatory changed in June 2003. These are now: 

nameQobs.u-bordeauxl.fr 

I httD://uuv.obs.u-bordeauxl.fr 1 

2. Scientific Staff 

Our group is composed of the following three individuals, who are involved part or full time in 

0 Patrick Charlot (50%): overall responsibility for Analysis Center work and data processing. 

He is the PI of the ICRF densification project on the EVN. He is also involved in radio source 

imaging and has a major interest in studying source structure effects in geodetic VLBI data. 

0 Antoine Bellanger (100%): engineer with background in statistics and computer science. His 

main role is to conduct initial data processing and develop analysis tools as needed. In the 

future, he will also maintain a web site dedicated to our analysis activities. 

0 Alain Baudry (10%): radioastronomy expert. He is involved in the ICRF densification project 

IVS analysis and research activities, as described below: 

and has interest in radio source imaging. 

166 IVS 2003 Annual Report 
Observatoire de Bordeaux Bordeaux Observatory Analysis Center 

3. Analysis and Research Activities during 2003 

During the past year, our level of activity has been stable. On the analysis side, we have 

completed initial processing of all NEOS-A and NSR4 sessions conducted between 1999 and 2003 

and have started to analyze the 2003 IVS-R1 sessions. Additionally, we have derived preliminary 

time series of source positions based on this data set. Figure 1 shows an example of such "arc" 

positions (monthly estimates) for the source 0229+131. These results will be refined in the future 

while we keep on analyzing new sessions as they become available. 

Right kcenen (ms) Declination (mas) 

c N 0 

+ + 

m m m N s;s N 

0 

*.- !E 

$0 $- 

* 

N 12O 

I 

110 

+ 

I 

0.- 

I 

2000 2002 2004 2000 2002 2004 

Epoch Epoch 

Figure 1. Mmated monthly coordinates for the source 0229+131 between 1999 and 2003. 

On the research side, we have pursued further our observing program for densifying the ICRF 

in the northern sky. As described in [l], the aim of this project is to add 150 new sources at 

carefully selected sky locations to fill the "empty" regions of the frame and improve the overall 

source distribution. Following our initial two experiments in 2000 and 2002 (each observing 50 new 

sources) [4, 51, an additional third experiment was carried out on October 27, 2003, to complete 

this project. The network used for the latter comprised seven telescopes from the European VLBI 

Network (EVN) along with three external non-EVN geodetic stations that agreed to join this 

project. The participating telescopes are listed in Table 1. The data from this experiment have 

just been correlated with the Bonn Mark IV correlator. Final fringe-fitting, data export, and 

astrometric analysis should be conducted shortly. 

Table 1. Network used in third ICRF densification experiment. 

EVN telescopes I Non-EVN telescopes 1 

Effelsberg Algonquin Park 

Ny Alesund 

Onsala 

Hartebeestoek 

Urumqi 

Shawhai 

IVS 2003 Annual Report 167 
Bordeaux Observatory Analysis Center Observatoire de Bordeaux 

Another achievement is the evaluation of astrometric suitability for an additional 60 ICRF 

sources based on newly-available X- and S-band maps in the Radio Reference Frame Image 

Database. Structure indices were derived according to the average structural delay effects for 

these sources following our standard scheme [6]. Overall, structure indices are now available for 

450 ICRF sources, about 75% of the total number of ICRF sources [7]. Analysis of the structure 

index distribution shows that 57% of the sources in this sample have a structure index value of 

either 1 or 2 at X band, indicating compact or very compact structure. At S band, structural 

effects are less significant (89% of the sources have a structure index value of either 1 or 2), a 

consequence of the fact that the S-band structure corrections are scaled down as a result of the 

dual-frequency group-delay calibration applied to eliminate propagation effects in the ionosphere. 

Additionally, we have also evaluated the astrometric suitability of 108 ICRF sources at K band 

(24 GHz) and Q band (43 GHz) based on data acquired by the VLBA K-Q Survey collaboration [8] 

in May, August and December 2002. The major goals of this project are to extend the ICRF in 

the 24-43 GHz range and to enhance VLBI phase-referencing at high frequency by increasing 

the number of calibrators available at these frequencies. As reported in [7], comparison of the 

structure index distribution at K and Q bands with that at the standard X band frequency is 

striking, indicating a larger portion of structure index values of 1 as observing frequency increases 

(32% at 8 GHz, 56% at 24 GHz, and 71% at 43 GHz). Hence, these initial results already suggest 

that the astrometric suitability of the sources is significantly better at 24 GHz and 43 GHz than 

at the standard 8 GHz geodetic observing frequency. 

4. Outlook 

During the year 2004, our plans include the following: 

Refine our “arc position” analysis of the 1999-2003 NEOS-A and IVS-R4 sessions to monitor 

the temporal evolution of the source coordinates, and keep on analyzing the new IVS 2004 

sessions as they become available. 

Finish up post-processing and analysis for all three ICRF densification experiments, and 

compare the derived astrometric positions with those from the VLBA Calibrator Survey. 

Continue to evaluate the astrometric suitability of the ICRF sources as new maps become 

available at S, X, K and Q bands, and make the corresponding structure indices and structure 

correction images available through our web page. 

Assess more precisely the impact of massive source structure modeling in astrometric data 

analysis by repeating our previous test on the RDV data 191 after identification of the most 

appropriate structural reference feature for each source. 

Start processing RDV experiments in cooperation with the USNO team to monitor the Xand S-band structural evolution of the ICRF sources and extend the time basis of the current 

image data base. 

Redesign our web page1 to make multi-epoch and multi-frequency structure indices and 

false color structure correction images publicly available, along with results of source position 

stability, for possible use by IVS operation and analysis centers. 

’ http://www.obs.u-bordeaux1 .fr/public/radio/PCharlot/structure.html 

IVS 2003 Annual Report 
Bordeaux Observatory Analysis Centa Obserwtoire -- de Bordeaux 

I 

References 

[l] Charlot, P., Viateau, B., Baudry, A., Ma, C., Fey, A. L., Eubanks, T. M., Jacobs, C. S., Sovers, 

0. J.: 2000, A Proposed Astrometric Observing Program for Densifying the ICRF in the Northern Hemisphere, rVS 2000 General Meeting Proceedings, Eds. N. R. Vandenberg and K. D. Baver, 

[2] Charlot, P.: 2002, Modeling Radio Source Structure for Improved VLBI Data Analysis, IVS 2002 

General Meeting Proceedings, Eds. N. R. Vandenberg and K. D. Baver, NASA/CP-2002-210002, p. 233- 

242. 

231 Sovers, 0. J., Jacobs, C. S.: 1996, Observation Model and Parameter Partials for the JPL VLBI 

Parameter Estimation Software "MODEST"-1996, JPL Publication 83-39, Rev. 6, August 1996. 

[4] Charlot, P., Viateau, B., Baudry, A.: 2001, Bordeaux Observatory Analysis Center Report, International VLBI Service for Geodesy and Astrometry 2000 Annual Report, Eds. N. R. Vandenberg and K. 

D. Baver, NASA/TP-2001-209979, p. 203-206. 

[5] Charlot, P., Bellanger, A., Baudry, A.: 2003, Bordeaux Observatory Analysis Center Report, International VLBI Service for Geodesy and Astrometry 2002 Annual Report, Eds. N. R. Vandenberg and K. 

D. Baver, NASA/TP-2003-211619, p. 228-231. 

[6] Fey, A. L., Charlot, P.: 2oO0, VLBA Observations of Radio Reference Frame Sources. III. Astrometric 

Suitability of an Additional 225 Sources, ApJS, 128, 17-83. 

[7] Charlot, P.: 2003, Extended Emission Structure in Extragalactic Sources, IAU XXV General Assembly, Joint Discussion 16: The International Celestial Reference System, Maintenance and Future 

Realizations, Eds. R. Gaume, D. D. McCarthy and J. Souchay (in press). 

[8] Jacobs, C. S., Jones, D. L., Lanyi, G. E., Lowe, S. T., Naudet, C. J., Resch, G. M., Steppe, J. A., 

Zhang, L. D., Ulvestad, J. S., Taylor, G. B., Sovers, 0. J., Ma, C., Gordon, D., Fey, A. L., Boboltz, 

D. A., Charlot, P.: 2002, Extending the ICRF to Higher Radio Frequencies, WS 2002 General Meeting 

Proceedings, Eds. N. R. Vandenberg and K. D. Baver, NASA/CP-2002-210002, p. 350-354. 

[9] Sovers, 0. J., Charlot, P., Fey, A. L., Gordon, D.: 2002, Structure Corrections in Modeling VLBI 

Delays for RDV Data, IVS 2002 General Meeting Proceedings, Eds. N. R. Vandenberg and K. D. 

Baver , NASA / CP- 2002-2 10002, p . 243-247. 

NASA/CP-2000-209893, p. 168-172. 

IVS 2003 Annual Report 169 
Matera CGS VLBI Analysis Center Centro di Geodesia Spaziale (CGS) - Telespazio 

Matera CGS VLBI Analysis Center 

Roberto Lanotte, Giuseppe Bianco 

Abstract 

This paper reports the VLBI data analysis activities at the Space Geodesy Center (CGS) at Matera 

from January 2003 through December 2004 and the contributions that the CGS intends to provide for 

the future as an IVS Data Analysis Center. 

1. Introduction 

The Matera VLBI station became operational at the Space Geodesy Center (CGS) of the 

Italian Space Agency (ASI) in May 1990. Since then it is active in the framework of the most 

important international programs. VLBI data analysis activities are performed at CGS for a 

better understanding of the tectonic motions with specific regards to the European area. The 

CGS, operated by Telespazio on behalf of ASI, provides full scientific and operational support 

using the main space geodetic techniques: VLBI, SLR, LLR and GPS. 

2. Analysis Activities in 2003 

The VLBI data analysis activities at the CGS in the year 2003 were directed towards the 

realization of a global VLBI analysis, named cgs2004a, using the CALC/SOLVE software (developed at the GSFC). The cgs2004a will be included in the IVS solutions “pool” and its main 

characteristics are: 

a Data span: 

1980.04.11 - 2003.10.30 

a Estimated Parameters: 

- Celestial Frame: 

right ascension and declination as global parameters for 554 sources and as local parameters for 17 sources. 

- Terrestrial Frame: 

Coordinates and velocities for 44 stations as global parameters and as local parameters 

for 66 stations. 

- Earth Orientation: 

Unconstrained X pole, Y pole, UT1, Xp rate, Yp rate, UT1 rate, dpsi and deps. 

The CGS is contributing to the IVS project “Tropospheric Parameters”. 

3. Future Plans 

a Participate in the IVS pilot project “Time series of baseline lengths“ 

a Continue and improve the realization of global VLBI analysis. 

Continue to participate in IVS analysis projects. 

170 IVS 2003 Annual Report 
Centro di Geodesia Spaziale (CGS) - Telespazio __ Matera CGS VLBI Analysis Center 

4. Staff at CGS contributing to the IVS Analysis Center 

- Dr. Giuseppe Bianco, Responsible for CGS, AS1 (primary scientific/technical contact). 

- Dr. Cecilia Sciarretta, Responsible for scientific activities, Telespazio. 

- Dr. Roberto Lanotte, Geodynamics data analyst, Telespazio. 

171 
CRL Analysis Center Kashima Space Research Center, Communications Research Laboratory 

Analysis Center at Communications Research Laboratory 

Ryuichi Ichikawa, Mamoru Sekido, Hiroo Ohsaki, Yasuhiro Koyama, Tetsuro Kondo 

Abstract 

This report summarizes the activities of the Analysis Center at the Communications karch 

Laboratory (CRL) for the year 2003. By using the newly developed PC-based data acquisition and 

data processing system (K5 VLBI system), we performed the international eVLBI sessions twice and 

we demonstrated a rapid estimation of UT1-UTC less than one day after the observations on June 27, 

2003. We also performed more than 30 VLBI experiments for the two Japanese spacecraft, NOZOMI 

and HAYABUSA from September 2002 until November 2003. These VLBI experiments are aimed to 

establish positioning technology for interplanetary spacecrafts in realtime. 

1. General Information 

The CRL analysis center is located in Kashima, Ibaraki Japan. It is operated by the Radio 

Astronomy Applications Group, Kashima Space Research Center of CRL. VLBI analyses at CRL 

are being mainly concentrated on experimental campaigns for developing new techniques such as 

differential VLBI (DVLBI) for spacecraft orbit determination and e-VLBI measurements for realtime EOP determination. In addition we are now preparing to perform a feasibility experiment 

of GPS and VLBI data transmission using a satellite communication link through the TCP/IP 

protocol from the South Pacific to Japan. We are also conducting a water vapor radiometer 

(WVR) observation in Kashima and a numerical simulation of atmospheric parameters (equivalent 

zenith wet delay and linear horizontal delay gradients) estimated by ray-tracing through the nonhydrostatic numerical weather prediction model (NHM). 

2. Staff 

The staff members who are contributing to the Analysis Center at the CRL are listed below: 

0 Kondo Tetsuro, Responsible for overall operations and performance. 

0 Koyama Yasuhiro, Development of data analysis software for geodetic experiments. 

0 Sekido Mamoru, Development of data analysis software for DVLBI. 

0 Ohsaki Hiro, Development of data analysis software for DVLBI. 

0 Ichikawa Ryuichi, Development of data analysis software for DVLBI and atmospheric modeling. 

3. Current Status and Activities 

3.1. Geodetic VLBI Experiments 

Two geodetic VLBI sessions were carried out to evaluate the performance and functions of the 

K5 VLBI system [Koyama et a1.,(2003a)[l]]. The first session was performed for about 24 hours 

from January 31, 2003 using Kashima34-Koganei baseline. The second experiment was performed 

for about 24 hours from July 14, 2003 using five VLBI stations at Kashima (34m), Tsukuba (32m), 

172 IVS 2003 Annual Report 
Kashima Space Research Center, Communications Research Laboratory CRL Analysis Center 

Tomakomai (llm), Gifu (llm), and Yamaguchi (32m). The example of the results are shown in 

Table 1. The comparison of the RMS residuals of delay and delay rates suggests the performance 

of the K5 systems is better than the K4 systems. 

Table 1. Comparison of Kashima 11 - Koganei 11 baseline lengths estimated fkom the data obtained with 

K4 and K5 system on Jan. 31,2003. 

No. of valid data Baseline Length RMS Residual ~ 

(mm) Delay(psec) Rate(&/=) 

K4 112 109099657.0f6.7 76 136 

K5 159 109099641.2f3.2 33 92 

3.2. Real-time EOP Measurements 

We performed a test e-VLBI session for two hours from 16:00 UT on March 25, 2003 with 

the Kashima-Westford baseline [Koyama et al.,(2003b)[2]]. The 34m antenna VLBI station at 

Kashima and the 18-m antenna station at Westford were used for the observations. This was the 

fourth test in the series of e-VLBI test observations. During the previous tests, successful detections 

of the fringes from the e-VLBI observations were demonstrated and the software developments have 

been continued with the data sets obtained. The estimated UT1-UTC value is shown in the Table 

2 as well as the values published in the IERS Bulletin B. 

? 

Table 2. Estimated value of UT1-UTC from the Kashima-Westford e-VLBI session and reported values 

from IERS Bulletin B 183, May 2, 2003. 

Epoch (UT) UT1-UTC(psec) 

e-VLBI 20:OO on Mar. 25 -338727.0f23.9 

IERS 00:OOonMar.25 -337951 

IERS 00:OO on Mar. 26 -338610 

The next e-VLBI session was performed for two hours beginning at 13:00 UT on June 27, 2003. 

The observation mode, codguration of the observing system, and the baseline were identical 

to the previous e-VLBI session performed in March, 2003. The purpose of the session was to 

demonstrate how fast the UT1-UTC can actually be estimated from the international eVLBI 

session. 

Table 3 shows the actual time sequence of the observations, file transfers, and data processing 

during the e-VLBI session. As shown in Table 3, the UT1-UTC was estimated within 21 hours 

and 20 minutes after the session finished. Thus the rapid estimation of EOP in less than one day 

was successfully demonstrated by the international e-VLBI observations and data analysis. 

3.3. Differential VLBI 

Precise spacecraft positions (510 nrad) can be obtained with differential spacecraft-quasar 

VLBI (DVLBI) observations that directly measure the angular position of the spacecraft relative 

IVS 2003 Annual Report 173 
CRL Analysis Center Kashima Space Research Center, Communications Research Laboratory 

TIME(UT) 

Time 

Event 

Event 

22:oo 

0o:oo 

-04:20 

-08:lO 

-20:30 

Observations Start 

Observations End 

File extraction and transmission 

From Kashima to Westford: 

From Westford to Kashima: 

File Conversion (Mark5 to K5) 

Software Correlation 

l07Mbps (41.54GByte in 51m 35s) 

44.6Mbps (41.54GByte in 2hr 04m 02s) 

-21:20 1 Bandwidth Synthesis Processing, Database Generation, Data Analysis 

to nearby quasars. We performed more than 30 VLBI experiments for the two Japanese spacecraft, 

NOZOMI (“Hope”) and HAYABUSA (“Falcon”) from September 2002 until November 2003 [see 

Ichikawa et al., 2003[3] and Sekido et al., 2003[4] in detail]. These VLBI experiments are aimed to 

establish positioning technology for interplanetary spacecraft in realtime. 

The final products obtained from the NOZOMI VLBI experiments were available with approximately 30 hours latency as shown in Figure 1. On the other hand, the removable data hard disks 

at other stations (Tomakomai, Tsukuba, Yamaguchi, and Algonquin) 

Thus, the latency to product the group delays using these station data 

were mailed to Kashima. 

were up to several days. 

production of data 

for ISAS 

analysis 

(-3 hour) 

Figure 1. Schematic image showing NOZOMI VLBI data flow and analysis 

Preliminary results demonstrate that the VLBI delay residuals are consistent with R&RR 

observables. However, the rms scatter between them is relatively large up to several tens of 

174 IVS 2003 Annual Report 
Kashima Space ____ Research ~- Center, Communications Research Laboratory CRL Analysis Center 

nanoseconds. We are now evaluating our VLBI group delays by comparing with the R&RR results 

more deeply. 

We are now preparing to perform another VLBI experiment. One of the candidate targets is 

HAYABUSA, which was developed to investigate asteroids. HAYABUSA was launched on May 

9, 2003 [JAXA, 2003][5]. The first HAYABUSA VLBI experiment was successfully carried out 

November 26, 2003. We are now evaluating the obtained HAYABUSA group delays by comparing 

with the R&RR results. 

3.4. Evaluation of Atmospheric Model 

Observations of atmospheric slant delay using water vapor radiometer (WVR) nearby the 

Kashima 11-m antenna are carried out for detecting and characterizing water vapor variations. 

We are also evaluating atmospheric parameters (equivalent zenith wet delay and linear horizontal 

delay gradients) and positioning errors derived from slant path delays obtained by ray-tracing 

through the non-hydrostatic numerical weather prediction model (NHM) with 1.5 km horizontal 

resolution. 

4. F'uturePlans 

During the year 2004 the plans of the Analysis Center at CFtL include: 

0 Several international and domestic VLBI experiments for real-time EOP determinations using 

0 Development of analysis software for spacecrafts positioning using phase delay observables 

0 Improvement of processing speed and efficiency for VLBI data correlation using multipm 

0 Comparisons of the tropospheric parameters derived from VLBI, GPS, WVR and nonIn addition KSP data sets are still available at the UlU http://ksp.crl.go.jp/index.html. General 

http: //www2.crl .go.j p/ ka / rad ioastro/ i ndex. htm I. 

the eVLBI and K5 systems (both IP-VLBI system and PC/VSI system). 

cessor and high speed network 

hydrostatic numerical weather prediction data. 

information about VLBI activities at the CFU is provided at 

References 

[l] Koyama et al., Evaluation of the K5 system in geodetic VLBI experiments, IVS CRL/TDC News, No. 

23, pp 26-30,2003. 

[2] Koyama et d., Rapid Turn Around EOP Measurements by VLBI over the Internet, IUGG proceedings, 

2003. 

[3] Ichikawa et al., An evaluation of VLBI observations for the positioning of the NOZOMI Spacecraft 

and the future direction in research and development of the deep space tracking using VLBI, IVS 

CRL/TDC News, No.23, pp 31-33, 2003. 

[4] skido et al., VLBI Application for Spacecraft Navigation (NOZOMI) -follow-up on Model and Analysis, lVS CRL/TDC News, No.23, pp 3435, 2003. 

[SI JAXA web site, http://www.musesc.isas.jaxajp/English/index.html, 2003. 

I 

~~ 

IVS 2003 Annual rteport 175 
DGFI Analysis Center DGFI, Deutsches Geodatisches Forschungsinstitut 

DGFI Analysis Center Annual Report 2003 

Voiker Tesmer, Hansjorg Ku tterer, Hermann Drewes 

Abstract 

This report summarizes the activities of the DGFI Analysis Center in 2003 and outlines the planned 

activities for the year 2004. 

1. DGFI Analysis Center Operation 

The German Geodetic Research Institute (Deutsches Geodatisches Forschungsinstitut, DGFI) 

is an autonomous and independent research institution located in Munich. It is supervised by 

the German Geodetic Commission (Deutsche Geodatische Kommission, DGK) at the Bavarian 

Academy of Sciences. The research covers all fields of geodesy and includes the participation in 

national and international research projects as well as functions in international bodies. 

The long-term research programme of DGFI is based on the general theme “Fundamentals of 

Geodetic Reference Systems”. The definition of geodetic reference systems is studied and methods 

for their realisation with modern space geodetic techniques are developed. Geodetic observations 

are analysed, approaches for the data processing are set up, tested and exemplarily applied (see 

DGFI web server http : //ww . dgf i . badw . de). 

DGFI contributes to the International VLBI Service (IVS) as an Analysis Center to improve the 

space-geodetic observation technique Very Long Baseline Interferometry (VLBI) and the analysis 

of its observations, respectively, by participating in pilot projects and by research projects which 

are mainly concerned with the modelling of VLBI observations. 

2. Activities in 2003 

1. Refinement of the stochastic model of VLBI observations 

Up to now, improvements of modelling the observations of “Very Long Baseline Interferometry (VLBI)” are mainly achieved by refining the functional representation of the geometricalphysical properties of the observations. Further progress in this field requires big efforts and 

is not possible with any precision. In contrast, the stochastic properties of the observations 

(which comprise functionally not representable influences) have not been handled thoroughly. 

The refinement of the stochastic VLBI model considered here is based on two principal ideas: 

(1) Discrepancies between the functional model and the observations can be understood at 

least approximately as variances of the observations. (2) Deficits of the functional model 

which affect several observations more or less systematically might be interpreted as covariances (correlations) between observations. For this reason, the deficits of the stochastic 

model of VLBI observations were studied in order to set up a more adequate structure of 

the variance-covariance matrix of the observations. The associated unknown variance and 

covariance components were estimated according to the MINQUE principle. 

The most significant improvements of the conventional stochastic VLBI model were found 

to be related to the observing stations (site-specific effects) and the elevation angles (tropospheric effects) (see Tesmer, 2003). Although standard VLBI solutions can be improved by 

the refined stochastic model for the observations, its potential is not yet exhausted. 

~~ 

176 IVS 2003 Annual Report 
DGFI, Deutsches Geodiitisches Forschungsinstitut DGFI Analysis Center 

2. 

3. 

4. 

Parameter constraints in VLBI data analysis 

It is common practice in VLBI parameter estimation to model two types of parameters. On 

the one hand there are classical target parameters such as station coordinates and Earth 

orientation parameters. On the other hand there are additional parameters like, e.g., the 

coefficients of the piecewise linear functions for the troposphere and the clocks as well as 

the offsets of the horizontal tropospheric gradients per station. In order to stabh the 

estimation, prior information on the additional parameters is added by means of pseudoobservations (soft constraints). For assessing the impact of these constraints on the VLBI 

results, several aspects were studied such as the bias of the parameters, the respective contribution of the constraints to the estimation, and the consistency of observed data and prior 

information. Numerical results were derived from the NEOS-A sessions of 2000 and 2001 

using the VLBI software OCCAM 5.0 (Least Squares Method). 

Typically, the induced parameter bias is visible in the results but it is not significant. However, in sessions with extended gaps of observation data the results can be strongly iduenced. 

The contribution of the constraints to the estimated parameters (in terms of partial redundancies calculated for the constraints) is rather moderate in the standard case but becomes 

dominant in case of increased weights, in particular for the gradient ofhets. This is underlined by results for the statistical consistency of the constraints and the observed data. 

Particular care must be taken in case of weakly configured networks, which can be due to 

temporary losses of observations on single VLBI sites. For details see Kutterer (2003). 

CONTO2 VLBI normal equations for a rigorous combination with GPS 

From 16th to 31st of October 2002, the CONTOB VLBI observation campaign, which was 

initiated by the IVS, was carried out. This campaign is especially suitable for the combination 

of VLBI observations with those of other spacegeodetic techniques. 

In order to provide the optimum conditions for combining VLBI and GPS as rigorously as 

possible, much care was taken to set up VLBI normal equations with models and estimated 

parameters which are adapted to those of the used GPS normal equations. The following 

models or parameter representations had to be verified or modified, respectively, in the VLBI 

software OCCAM: solid Earth tides, pole tide, ocean loading, tropospheric delay, subdaily 

EOP variations, daily a-priori EOP values and their interpolation as well as the nutation 

model. The VLBI observation data were additionally reformatted from 24h blocks, beginning 

at 18 h UTC to blocks beginning at 0 h UTC in order to avoid a potential error source. The 

normal equations were supplied in the SINEX 1.0 format. First CONT02 combination results 

of VLBI and GPS data are for example reported in Thaller et al. (2003). 

IVS OCCAM working group 

The software OCCAM which is used at DGFI to analyse VLBI observations is continudy 

improved by a group of scientists from Geoscience Australia (Canberra, Australia), the Vienna University of Technology (Vienna, Austria), the St. Petersburg University, the Institute 

of Applied Astronomy (both St. Petersburg, Russia) and DGFI. As the groups concentrate 

on different research fields, an official version (currently 6.0) of the source code is kept which 

reflects the common interest. This version is updated if needed. The group met twice on 

the occasion of international scientific meetings (4th IVS Analysis meeting in Paris, France; 

Les Joumk 2003, St. Petersburg, Russia) in order to defme and to partially elaborate the 

source code changes. DGFI’s most important contributions to the new version of OCCAM 

IVS 2003 Annual Report 177 
DGFI Analysis Center DGFI, Deutsches Geodatisches Forschungsinstitut 

are an advanced outlier rejection routine (Kutterer et al., 2003) and a first version of a refined 

stochastic model for VLBI observations (see Tesmer, 2003). There is also a new interface for 

the conversion of OCCAM internal normal equations into a DOGS-CS readable format. 

3. Staff 

The personnel of DGFI involved in the IVS Analysis Center during 2003 did not change w.r.t. 

2002, notably Hermann Drewes, Hansjorg Kutterer and Volker Tesmer. Volker Tesmer was funded 

externally by the German research association ‘Deutsche Forschungsgemeinschaft (DFG)’ under 

the contract DR 143/11-1. 

4. Plans for 2004 

The primary contributions will be to participate in further Pilot Projects of IVS. Additionally, 

DGFI will take part in the IVS VLBI2010 Working Group. In the medium term, DGFI aims 

to become an operational IVS Analysis Center, which would imply a commitment to regularly 

contribute to the official IVS products. Other research goals will be: 

0 Further improvement of the VLBI software OCCAM 

0 Simultaneous and consistent determination of a TRF, a CRF and the EOP in one solution 

using minimum datum constraints 

0 Combined estimation and comparative analysis of geodetic target parameters from VLBI 

and GPS observations 

5. References 

Kutterer, H.: The Role of Parameter Constraints in VLBI Data Analysis. In: Schwegmann, 

W., Thorandt, V. (eds): Proc. 16th Working Meeting on European VLBI for Geodesy and Astrometry, Bundesamt fiir Kartographie und Geodkie, Fkankfurt/Leipzig, 171-180, 2003 

Kutterer, H., R. Heinkelmann, V. Tesmer: Robust Outlier Detection in VLBI Data Analysis. 

In: Schwegmann, W., Thorandt, V. (eds): Proc. 16th Working Meeting on European VLBI for 

Geodesy and Astrometry, Bundesamt fur Kartographie und Geodkie, Fkankfurt/Leipzig, 247-256, 

2003 

Thaller, D., R. Schmid, M. Rothacher, V. Tesmer, D. Angermann: Rigorous Combination of 

VLBI and GPS Using the CONT02 Campaign. Submitted to the IAG Proc. of the XXIII. IUGG 

General Assembly, Sapporo, 2003 

Tesmer, V.: Refinement of the Stochastic VLBI Model: First Results. In: Schwegmann, W., 

Thorandt, V. (eds): Proc. 16th Working Meeting on European VLBI for Geodesy and Astrometry, 

Bundesamt fur Kartographie und Geodkie, Fkankfurt/Leipzig, 207-218, 2003 

178 IVS 2003 Annual Report 
Forsvarets forskningsinstitutt (FFI) (Norwegian Defence Research Establishment) ~. FFI Analysis Center 

FFI Analysis Center 

Per Helge Andersen 

Abstract 

FFI’s contribution to the IVS as an analysis center will focus primarily on a combined analysis at the 

observation level of data from VLBI, GPS and SLR using the GEOSAT software. This repd shortly 

summarises the current status of analyses performed with the GEOSAT software. FFI is currently 

Analysis Center for IVS and ILRS, Technology Development Center for IVS, and Combination Ftesearch 

Center for IERS. 

1. Introduction 

Recently, a number of colocated stations with more than one observation technique have been 

established. In principle, all instruments at a given colocated station move with the same velocity 

and it should be possible to determine one set of coordinates and velocities for each colocated 

site. In addition, a constant eccentricity vector from the reference point of the colocated station 

to each of the individual phase center of the colocated antennas is estimated using constraints in 

accordance with a priori information given by the ground surveys. One set of Earth orientation 

parameters (EOP) and geocenter coordinates can be estimated from all involved data types. The 

present dominating error source of VLBI is the water content of the atmosphere which must be 

estimated. The introduction of GPS data with a common VLBI and GPS parameterization of 

the zenith wet delay and atmospheric gradients will strengthen the solution for the atmospheric 

parameters. The inclusion of SLR data, which is independent of water vapour, give new information 

which will help in the de-correlation of atmospheric and other solve-for parameters and lead to 

more accurate parameter estimates. These, and many more advantages with the combination of 

independent and complementary space geodetic data at the observation level, are fully accounted 

for with the GEOSAT software developed by FFI during the last 17 years. 

2. StafF 

Dr. Per Helge Andersen - Research Professor of Forsvarets forskningsinstitutt (FFI) and Institute of Theoretical Astrophysics, University of Oslo. 

3. Combination of VLBI, GPS, and SLR Observations at the Observation Level 

Only test analyses performed in 2003. 

The GEOSAT software is presently undergoing extensive development. Some of the changes 

are explained in our technical development report. 

IVS 2003 Annual Report 179 
GIUB/BKG Analysis Center Geodatisches Institut der Universitat Bonn 

The GIUB/BKG VLBI Analysis Center 

Axel Nothnagel, Gerald Engelhardt, Volkmar Thorandt, Markus Vennebusch, 

Dorothee Fischer 

Abstract 

The activities at the GIUB/BKG VLBI Analysis Center for the year 2003 consist of routine computations of Earth orientation parameter (EOP) time series and a number of research topics in geodetic 

VLBI. At BKG the new interactive graphic tool REPA [l] was developed for the VLBI Analysis Software Calc/Solve (21. In 2003 the VLBI group at BKG has started regular submissions of tropospheric 

parameters for the IVS-R1 and IVS-R4 sessions, and generating of daily SINEX (Solution INdependent Exchange format) files for IVS. Quarterly updated solutions were computed for the IVS products 

Terrestrial Reference Frame (TRF) and Celestial Reference Frame (CRF). At GIUB analysis activities concentrated on investigations concerning the Wettzell - Tsukuba K4 UT1 Intensive series and on 

combinations of VLBI data using SINEX files. 

1. General Information 

The GIUB/BKG VLBI Analysis Center has been established jointly by the Bundesamt fur 

Kartographie und Geodikie (BKG), Leipzig, and the Geodetic Institute of the University of Bonn 

(GIUB). Both institutions closely cooperate in the field of geodetic VLBI maintaining their own 

analysis groups in Leipzig and Bonn. The responsibilities include data analysis and software development. BKG is responsible for the computation of EOP time series and tropospheric parameters 

of the IVS-R1 and IVS-R4 sessions, the generating of daily SINEX files, and quarterly updated 

global solutions for the TRF and the CRF. 

On May 9-10, 2003 the 16th Working Meeting on European VLBI for Geodesy and Astrometry 

was organized by the BKG and took place at the BKG branch at Leipzig [3]. 

2. Data Analysis 

At BKG the Mark 5 VLBI data analysis software system Calc/Solve, release of September 25, 

2003 [2], is currently used for VLBI data processing. In addition, the older Mark 4 version, release 

of May 15,2003 and an independent program environment for the Calc/Solve software are available. 

The latter is used for the pre- and post-interactive part of the EOP series determination. The Mark 

4 Calc/Solve software under Fortran77 is installed on a HP9000/280/1 workstation with an HPUX10.20 operating system and the Mark 5 software under Fortran90 on another HP workstation 

with an HP-UX1l.OO operating system. 

0 Processing of correlator output 

The BKG group continued the generation of calibrated databases for the sessions correlated 

at the MPIfR/BKG Mark 5 Astro/Geo Correlator at Bonn (e.g. R1, T2, OHIG, EURO) and 

submitted them to the IVS Data Centers for distribution. 

0 IVS EOP time series 

The EOP time series bkg00003, bkg00004, and bkg00005 computed from 24 hour VLBI 

sessions were replaced by the series bkg00006 with all 24 hour sessions since 1984 suitable for 

EOP determination. The main differences to the older series are the use of a new a priori TRF 

180 IVS 2003 Annual Report 
Geodattisches Institut der Universitat Bonn GIUB/BKG Analysis Center 

I 

~~~ 

IVS 2003 Annual Report 181 

called VTFW2003 [4] estimating TRF and CFW parameters in the global solution together 

with the EOP. From the beginning of 1984 to the end of 2003 altogether 2894 sessions of 

24hour observing time were processed. 

The EOP time series bkgint02 computed from the UT1 intensive sessions was replaced by 

the series bkgintO3. The new one is generated with fixed TRF (VTRF2003) and hed CRF 

derived from the global BKG solution for EOP determination. 1074 UT1 intensive sessions 

with about 1 hour measurement duration were analysed for the period between Jan. 1,1999 

to Dec. 31, 2003. 

For the IVS products TFW and CRF quarterly updated solutions were computed. There 

are no Werences in the solution strategy compared to the continuously computed EOP 

time series bkg00006. The results of the radio source positions were submitted to IVS in 

IERS format. The TRF solution is available in SINEX format, version 2.1, with station 

coordinates, velocities, and covariance matrix. 

0 Quarterly updated solutions for submission to IVS 

3. Research Topics 

0 Development of a new graphic tool for the Calc/Solve software 

The new interactive graphic tool REPA [l] has been implemented into the latest Calc/Solve 

releases. Both Fortran77 and Fortran90 versions are available. So it will be possible to 

transfer the program to LINUX. =PA allows the user to manage all necessary manipulations 

on VLBI observations and can create various plots of the baselines in the data base. The 

program can solve ambiguities for all baselines of a database in one step automatically. As 

of now the program is useful only for the data type "Group Delay and Rate". 

After the completion of the IVS Pilot Project - Tropospheric Parameters the VLBI group of 

BKG has started regular submissions of tropospheric parameters to IVS (wet and total zenith 

delays, horizontal gradients) for all IVS-R1 and IVS-R4 sessions since Jan. 1, 2002. The 

tropospheric parameters are directly extracted and transformed into SINEX for tropospheric 

estimates from the results of the solution for the EOP time series bkg00006. It is planned to 

submit long time series of tropospheric parameters &om 1984 on. 

The BKG VLBI group has started the regular submissions of daily SINEX files as base solutions for the planned IVS time series of baseline lengths and for combination techniques. In 

addition to the global solutions independent session solutions are computed for the parameter 

types station coordinates, EOP, and nutation parameters. 

Currently the IVS Analysis Centers at BKG and at GSFC regularly produce datum-free 

normal equation matrices of VLBI sessions while the USNO Analysis Center is testing its 

output. Thus, for selected epochs three different SINEX files (V. 2.0) are available which are 

used for extensive testing of the combination procedures on the basis of the DGFI DOCS-CS 

software. First efforts concentrate on the combination of earth orientation parameters (EOP) 

only. In a second step it is intended to combine TRFs as well. More details can be found in 

the proceedings of the Third NS General Meeting, Ottawa, Canada, February 9 - 11, 2004. 

0 IVS Product - Tropospheric Parameters 

0 Daily SINEX files 

0 Investigations of Solve SINEX Output for Combination 
GIUB/BKG Analysis Center Geodatisches Institut der Universitat Bonn 

0 Correlations between estimated parameters 

The investigations of correlations between estimated parameters have been continued now 

concentrating on a detailed analysis of the observation equations by singular-value decomposition. 

In 2003 thirty-one 1-hour sessions were observed in the Tsukuba-Wettzell K4 Intensive UT1- 

UTC Project. At Bonn the sessions have been analyzed in great detail. The main task is 

a consistent integration of the results in other series like the Wettzell-Kokee Park MK5 

UT1-UTC series. Figure 3 depicts the series based on differences w.r.t. the IERS C04 series 

together with the Wettzell - Kokee Park results using identical analysis strategies. 

0 Analysis of Tsukuba-Wettzell K4 UT1-UTC Intensive Observations 

UT1-UTC from Intensives relative to quadratic interpolation of C04 

0.15 

0.10 

P 

._ 2 0.05 

E 

- ._ 

I 

d 0 

q -0.00 

? 

2. 

P 

F -0.05 

lNTl (Wettzell - KO& Park) 

-0.10 * INTZ (Wettzell - Tsukuba) 

-0.1 5 

52750 52800 52850 52900 52950 53000 

MJD 

Figure 1. Residuals of Tsukuba - Wettzell and Kokee Park - Wettzell UT1-UTC Intensive Series w.r.t. 

IERS C04 

Questions on reference frames and analysis strategies have been investigated in view of a 

consistent integration of this series in other UT1 observing series. Apriori polar motion 

series and nutation modeling play an important role in the analysis. More details can be 

found in the proceedings of the Third IVS General Meeting, Ottawa, Canada, February 9 - 

11, 2004. 

182 IVS 2003 Annual Report 
GeocEtisches Institut der Universitfit Bonn I_ _. ~ 

GIUB/BKG Analysis Center 

4. Personnel 

Gerald Engelhardt 

Dorothee Fischer 

Axel Nothnagel 

Christoph Steinforth 

Volkmar Thorandt 

Dieter Ullrich 

Markus Vennebusch 

Wier Wojdziak 

Table 1. Personnel at GIUB/BKG Analysis Center 

BKG 

GIUB 

GIUB 

GIUB 

BKG 

BKG 

GIUB 

BKG 

++49-341-5634438 

++4422&732623 

++49-228733574 

++49-228732623 

++49-341-5634285 

++44341-5634328 

++4422&7335?0 

++44341-5634286 

geraldengelhardt @ bkg. bund.de 

dorothee.fischer @mi-bonn.de 

nothnagel@uni-bonn.de 

steinforth@uni-bonn.de 

volkmar .thorandt@bkg.bund.de 

dieter.ullrich@bkg.bund.de 

vennebusch@uni-bonn.de 

reiner.wojdziak@bk.bund.de 

References 

[l] Thorandt V., Engelhardt G. (2003): Residual Plotting and Ambiguity Resolution (REPA), In: Proceedings of the 16th Working Meeting on European VLBI for Geodesy and Astrometry, held at Leipzig, May 

09-10,2003, edited by W. Schwegmann and V. Thorandt, Bundesamt fiir Kartographie und GWie, 

Fr.ankfurt/Leipzig, 2003. 

[2] GSFC, NASA (2003): &lease of Mark-5 VLBI Analysis Software Calc/Solve from Sep. 25,2003 (webreference: http://gemini.gsfc.nasagav/solve). 

[3] Proceedings of the 16th Working Meeting on European VLBI for Geodesy and Astrometry, held at 

Leipzig, May 0410, 2003, edited by W. schwegmann and V. Thorandt, Bundesamt fiir Kartographie 

und Geodkie, Frankfurt/Leipzig, 2003. 

[4] VTRF2003: A Conventional VLBI Reference F'rame, Jun. 30, 2003 (web-reference: 

http://giub.geod.uni-bo~.de/vlbi/IVSAC/vtrfL003/vtrf2003.html) . 

IVS 2003 Annual Report 183 
GSFC Analysis Center NASA Goddard Space Flight Center 

GSFC VLBI Analysis Center 

David Gordon, Chop0 Ma, Dan MacMillan, Leonid Petrov, Karen Baver 

Abstract 

This report presents the activities of the GSFC VLBI Analysis Center during 2003. The GSFC 

Analysis Center analyzes all IVS sessions, makes regular IVS submissions of data and analysis products, 

and performs research and software development activities aimed at improving the VLBI technique. 

1. Introduction 

The GSFC VLBI Analysis Center is located at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. It is part of a larger VLBI group which also includes the IVS Coordinating Center, 

the Core Operation Center, a Technology Development Center, and a network station. The analysis 

center participates in all phases of geodetic and astrometric VLBI analysis, software development, 

and research aimed at improving the VLBI technique. 

2. Activities 

2.1. Analysis Activities 

The GSFC analysis group routinely analyzes all Mark 4 IVS sessions using the Calc/Solve 

system, and performs the AIPS post correlation analysis (phase calibration and fringe fitting) 

and the Calc/Solve analysis of the VLBA-correlated RDV sessions. It submits updated session 

EOP files and daily Sinex solutions for all IVS sessions to the IVS data centers immediately after 

analysis. Timeliness goals are 3 working hours after correlator release for Intensive submissions, 

and 1 working day for 24-hr Mark 4 submissions. The group submits analyzed databases to IVS for 

all INTOl NEOS Intensive, R1, RDV, CONT02, R&D, and APSG sessions. During 2003, the group 

processed and analyzed 168 24-hr sessions (49 R1, 53 R4, 6 RDV, 5 CONT02, 13 T2, 12 CRF, 6 

OHIG, 12 R&D, 5 EURO, 4 APSG, and 3 SURVEY sessions), 179 1-hr INTOl NEOS Intensive 

sessions, and 29 INTO2 Intensive sessions. The group also generates and submits quarterly updated 

TRF and CRF solutions to the IVS data centers using all suitable VLBI sessions. 

2.2. Research Activities 

The GSFC analysis group performs research aimed at improving VLBI analysis and modeling 

techniques, improving tropospheric and other geophysical modeling, improving the measurement 

and understanding of Earth orientation, maintaining and refining the celestial and terrestrial reference frames, and other related scientific investigations. The primary research activities undertaken 

during 2003 include the following: 

0 Mass loading: Observed VLBI site position variations have significant contributions at seasonal frequencies. To explain these variations, st& investigated the effect of various mass 

loading signals on crustal displacements measured by VLBI. Specifically, the effects of hydrological loading, atmospheric pressure loading, and non- tidal ocean loading were considered. 

Applying loading models for these three effects reduced annual vertical site amplitudes for 

184 IVS 2003 Annual Report 
NASA Goddard Space Flight Center GSFC Analysis Center 

-70% of the most frequently used VLBI sites by up to 2-3 111111, where the total observed 

amplitudes were generally 3-6 mm. Use of these models also improves baseline length repeatabilities except for some northern latitude sites where it is suspected that the snow 

component of the hydrologic model is not correct. 

0 Atmospheric pressure loading: Detailed investigations of atmospheric pressure loading were 

carried out. A rigorous procedure for computing atmospheric pressure loading was developed. 

A model for atmospheric tides was included. For all VLBI and SLR stations, the 3-D 

displacements due to atmospheric pressure loading were computed using the 6hr surface 

pressure fields from the National Centers for Environmental Prediction (NCEP). The error 

budget of the pressure loading time series was quantitatively estimated and the errors were 

found to be below 15%. The loading series were validated by comparing them with a dataset 

of 3.5 million VLBI observations for the period of 1980-2003. It was shown that, on average, 

only 5% of the amount of power present in the loading time series was not also present in 

the VLBI data. For the first time, horizontal displacements caused by atmospheric loading 

have been detected. Correction for atmospheric loading in VLBI produces a significant 

improvement in baseline length repeatabfity, except for the annual component. A paper on 

pressure loading was presented at the GPS meeting in Luxembourg in April 2003 (see Petrov 

and Boy, http://arXiv.org/abs/physics/O4Qll17), and a refereed paper (see Petrov and Boy, 

http://arXiv.org/abs/physics/O3l1096) was submitted to and accepted by JGR, to appear 

in 2004. On 18 March 2003, an atmospheric pressure loading service for VLBI and SLR was 

established. Series of 3-D displacements due to atmospheric pressure loading for all VLBI 

and SLR stations are updated daily. They are available at http://gemini.gsfc.nasa.gov/aplo. 

0 IMF: The impact of using an isobaric mapping function on VLBI analysis was investigated. 

The use of the NCEP Numerical Weather Model (NWM) to provide in situ atmosphere information for atmosphere delay mapping functions was evaluated using VLBI data spanning 11 

years. Parameters required by the IMF mapping functions were calculated from the NWM 

and incorporated into Calc/Solve. Compared with the NMF mapping functions, the application of IMF in global solutions demonstrates that the hydrostatic IMF mapping function, 

IMFh, provides both significant improvement in baseline length repeatability and noticeable 

reduction in the amplitude of the residual harmonic site position variations at semidiurnal 

to long-period bands. For baseline length repeatability, the reduction in the observed mean 

square deviations achieves 80% of the maximum expected for the change from NMF to IMF. 

On the other hand, the wet IMF mapping function, IMFw, as implemented using the NCEP 

data, results in a slight degradation of baseline length repeatability, probably due to the large 

grid spacing used by the NWM. A paper on this subject was presented at the GPS meeting 

in Luxembourg in April 2003 (see Niell and Petrov, http://arXiv.org/abs/physics/0401118). 

0 Antenna thermal deformation: Antenna thermal expansion and contraction can contribute 

significantly to a site’s annual vertical variations, with amplitudes as large as 3-4 mm. A 

simple model based on antenna dimensions and material expansion coefficients was applied 

in the VLBI analysis, along with the mass loading models. For many sites, the thermal 

expansion correction helps to reduce the annual vertical amplitudes. 

0 Quasar proper motions: When proper motions are estimated in the VLBI standard solutions, 

about 100 quasars are found with position uncertainties less than 50 pas/yr and apparent 

proper motions greater than 50 pas/yr. The weighted RMS of apparent proper motion is 

IVS 2003 Annual Report 185 
GSFC Analysis Center NASA Goddard Space Flight Center 

about 30 pas/yr in both right ascension and declination, which is significant compared to 

the ICRF noise floor given that the observed proper motions are from 1-2 decades of observing. For many sources, structure effects are certainly responsible for much of the observed 

apparent proper motion, and structure corrections are desirable. Based on analysis of the 

coherence of the pattern of observed proper motion over the sky, attempts are being made to 

estimate the galactic rotation rate. A presentation on this topic was made at the VLBA Tenth 

Anniversary Meeting, in Socorro, New Mexico, in June 2003 (see http://arXiv.org/abs/astroph/0309826). 

0 Gilcreek post-seismic behavior: Analysis of the time series of VLBI horizontal positions at 

Fairbanks shows that, over the year following the Denali fault earthquake of November 2002, 

the site velocity averaged -20 and -8 mm/yr faster to the South and East, respectively, in 

comparison to the long-term rate prior to the earthquake. The position variation roughly 

follows an exponential transient decay with a time constant of 2-3 months. Another year 

of data may be needed to determine whether the horizontal rates have returned to their 

pre-earthquake values. 

0 CONT02 analysis: Analysis of the CONT02 sessions showed that the baseline length precision 

is at the level of the best VLBI sessions and polar motion offset and rate estimates agree 

with those from GPS at the level of their formal uncertainties. The variance of subdaily EOP 

residuals (160-200 pas for X, Y, and UTI) to tidal models are not significant compared to the 

formal uncertainties of the subdaily estimates. This variance is similar to that for previous 

CONT campaigns. However, the subdaily EOP residuals do show modulated diurnal, semidiurnal, and 2-day variations. 

0 Antenna fixed axis tilt analysis: A Solve user-partial was used to estimate the tilts of all 

antennas with axis offsets in the RDV sessions. This study confirmed the tilt of the Pietown 

antenna, as first determined by NRAO using the pointing data. The pointing data shows 

a slowly increasing tilt, starting around 1991, and amounting to -3.75 arc-minutes at 206 

degrees azimuth, as of May 2003. Solve gives a tilt of -2.6 arc-minutes at 202 degrees 

azimuth, at an averaged epoch of -2000.0. Factoring in the difference in epochs, this is 

excellent agreement. The motion determined for Pietown is anomalous, showing an excess 

velocity of some 2 - 2.5 mm/yr to the SW, compared to Fort Davis, Los Alamos, and Kitt 

Peak, and cannot be explained by the geology of the region. Pietown’s increasing tilt, of -.3 

arc-min/yr, translates into -1.5 mm/year of motion to the SSW, if due to settling at the 

base of the antenna, and more if the settling/tilting is occuring deeper under the antenna. 

Thus, Pietown’s anomalous motion may be entirely due to local settling effects. 

0 High frequency CRF: Members of the analysis group are working with JPL, USNO, NRAO, 

and others, to extend the celestial reference frame to higher frequencies by using the VLBA 

at K and Q bands (-24 and -43 GHz). The primary goal is to build up a reference frame 

for use in planetary spacecraft navigation at Ka band (-33 GHz). Three sessions were analyzed during the year, a K-band survey and two K/Q sessions, using AIPS and Calc/Solve. 

Combined with two K/Q sessions from the previous year, the CRF determined shows declination dependent offsets from the X/S CRF, indicative of ionospheric effects. Though 

non-simultaneous, the K and Q observations were interpolated to obtain ionosphere corrections. Though these corrections add considerable noise to the solutions, they also appear to 

reduce the declination dependent errors. 

186 IVS 2003 Annual Report 
NASA Goddard Space Flight Center GSFC Analysis Center 

2.3. Software Development 

The GSFC group develops and maintains the Calc/Solve analysis system. Updates were re 

leased approximately bimonthly in 2003. Work in 2003 concentrated on the development of a 

Linux compatible version of Calc/Solve. Extensive upgrading of Calc for compliance with the 

IERS Conventions (2003) was begun and will be finished in 2004. 

3. Staff 

Members of the analysis group (and their areas of activity) include: Dr. Chop0 Ma (CFU?, 

TRF, EOP, and K/Q CRF analysis; IERS representative), Dr. Dan MacMillan (CFU?, TRF, EOP, 

mas loading, antenna deformation, proper motion, and post-seismic studies), Dr. David Gordon 

(database analysis; RDV and K/Q ClU? analysis; Calc development), Dr. Leonid Petrov (CRF, 

TRF, EOP, mass loading analysis; Calc/Solve development), Ms. Karen Baver (R4 and Intensives 

analysis, software development), and Ms. Cindy Villiard (data processing). 

4. FuturePlans 

Plans for the next year include: Finishing the update of Calc for compliance with the IERS 

Conventions (2003); finishing and releasing the first Linux version of Calc/Solve; participation in 

a third set of VLBA calibrator survey sessions; participation in additional K/Q observations and 

reference fiame development; and further research aimed at improving the VLBI technique. 

5. Publications 

Fomalont, E. B., L. Petrov, D. S. MacMillan, D. Gordon, C. Ma, "The Second VLBA Calibrator 

Petrov, L., C. Ma, "Study of Harmonic Site Position Variations Determined by VLBI", J. 

Survey: VCS2", Astronomical Journal, 126, 2562-2566, 2003. 

Geophys. Res., 108, No. B4, 2190, 2003. 

IVS 2003 Annual Report 187 
Haystack Analysis Center MIT Haystack Observatory 

MIT Haystack Observatory Analysis Center Report 

Arthur Niell 

Abstract 

The data from twenty years of the NCEP numerical weather model have been used to calculate 

the IMF hydrostatic mapping function for several sites distributed in latitude from -66" to +78". 

Comparison of heights estimated with the NMF hydrostatic mapping function demonstrates that using 

NMFh results in height errors at annual and semi-annual periods with amplitudes as large as approximately 8 mm and 4 mm, respectively, when data down to 5" are included. The errors are smallest at 

the equator and increase towards the poles. 

1. Geodetic Research at the Haystack Observatory 

The MIT Haystack Observatory is located approximately 50 km northwest of Boston, Massachusetts. Geodetic analysis activities are directed primarily to improving the accuracy of the 

estimation of atmosphere delay and thus reducing errors in the geodetic analysis. This work, along 

with operating the geodetic VLBI correlator and with supporting operations at the Westford, 

GGAO, Gilmore Creek, and Kokee Park geodetic sites, is supported by NASA through a contract 

with the Goddard Space Flight Center. 

2. Periodic Errors in Atmosphere Models 

New atmosphere mapping functions have been developed at MIT Haystack Observatory [4] 

and at Vienna University of Technology [2] that are based on Numerical Weather Models which 

provide in situ values for the atmosphere state variables of temperature, humidity, and pressure. 

These more accurate mapping functions then allow evaluation of the errors in previous generations 

of mapping functions. 

The NMF hydrostatic mapping function [3] depends only on day of year, latitude, and height 

above sea level. The time dependence is simply an annual sinusoid with a fixed phase for all 

sites. Thus, if the phase or amplitude is wrong, or if there are higher order harmonics in the true 

mapping function, estimates of the local height and zenith atmosphere delay made using NMFh 

will have errors at those periods. 

The IMF hydrostatic mapping function [4] has as the primary input parameter the 200 hPa 

geopotential height (hereafter referred to as 2200) above the VLBI site. Values of this parameter 

from the National Center for Environmental Prediction (NCEP) on a global 2.5" by 2.0" grid for 

0, 6, 12, and 18 UT .of each day from 1980 through the present are stored at the Goddard Space 

Flight Center. The values of z200 have been interpolated to the location of eight VLBI sites and 

three other locations in order to provide a comparison with NMFh. The surface pressure at each 

site was also obtained in order to calculate the atmosphere hydrostatic delay at 5". 

In order to convert the path delay at 5" into a height error, a simulation was used to obtain 

the scaling error of path delay change to height change. This simulation used a twenty-four hour 

GPS observing schedule, which may not give exactly the same results as current VLBI sessions, 

but is consistent (within 25 percent) with similar previous evaluations for VLBI data. 

The predicted height error for the Fairbanks site is shown in Figure 1. The sum of the annual 

and semi-annual terms of the series, as calculated by a Fourier transform, is superimposed. The 

188 IVS 2003 Annual Report 
MIT Haystack Observatory Haystack Analysis Center 

error is minimum in the winter and maximum in the late summer. This is consistent with the 

other sites in the northern hemisphere included in this evaluation. The error has the opposite sign 

in the southern hemisphere. 

The amplitudes of the annual and semi-annual errors for the eleven sites are shown in Figure 

2. 

A significant implication of this result is that using the more accurate mapping functions will 

reduce the annual height change (and baseline length change) that is characteristic of the degree-1 

deformations recently studied by [l]. 

3. Outlook 

Preliminary results of using IMF for analysis of the ensemble of VLBI data from 1980 through 

late 2002 confirm the expected reduction of periodic variation in baseline lengths 151. The necessary 

parameters for [2] have been extracted from the ECMWF by Johannes Boehm and can be similarly 

tested. 

Possible improvement could be obtained by raytracing the profiles of the NWMs, but this may 

require more computing capability than is currently available in the geodetic VLBI community. 

In the meantime, both IMF and VMF provide atmosphere parameterization that is more accurate 

than some other error sources for daily solutions. 

Future work will address the form of the wet mapping function as determined from much higher 

resolution numerical weather models. 

References 

111 Blewitt, G., D. Lavallee, P. Clarke, and K. Nurutdinov: A New Global Mode of Earth Deformation: 

[2] Boehm, J. and HSchuh: Vienna Mapping Functions in VLBI Analyses, Geophys. Res. Letters, 2004. 

[3] Niell, A.E.: Global mapping functions for the atmosphere delay at radio wavelengths, J. Geophys. Res., 

[4] Niell, A.E.: Improved atmospheric mapping functions for VLBI and GPS, Earth, Planets, and Space, 

[5] Niell, A. E., and L. Petrov, Using a Numerical Weather Model to Improve Geodesy, 2004 [available at 

Seasonal Cycle Detected, Science, 294,2342-23455, 2001. 

101, B2, 3227-3246, 1996. 

52, 699-702,2OoO. 

http:/arXiv.org/abs/physics/0401118] 

IVS 2003 Annual Report 189 
Haystack Analysis Center MIT Haystack Observatory 

fair 

30. 

1998.0 - 2003.0 

Figure 1. Height error for Fairbanks for 1998.0 - 2003.0 due to using NMFh, by comparison with IMFh, for 

5' minimum elevation. 

spectral comps of ZHD*(NMFh - IMFh) (1980-2oO2) 

n 

E 

E 

4 

E 

W 

1 

a 

(d 

c) .3 * 

I + annual 101 

8 

+ 

I x semi-annual 

+ 

,.- 0 

- .I._ - - 

-50 0 50 0' 

latitude 

Figure 2. Amplitudes of the annual and semi-annual terms of the height error resulting from using NMFh 

compared to IMFh for 5" minimum elevation. 

190 IVS 2003 Annual Report 
Institute of Applied Astronomy of Russian Academy of Sciences (IAA) IAA Analysis Center 

IVS 2003 Annual Report 191 

IAA VLBI Analysis Center Report 2003 

Zinovy Mdkin, Elena Skurikhina, Vadim Gu banov, Yuriy Rusinov, George Krasinsky, 

Nadia Shuygina 

Abstract 

The report contains a brief overview of IAA activity as IVS Analysis Center in 2003 and the plans 

for nearest future. 

1. General Information 

The IAA Analysis Center (IAA AC) is located at the Institute of Applied Astronomy of 

the Russian Academy of Sciences in St. Petersburg, Russia. The main fields of the activity 

include EOP service, computation of station and radio source coordinates, geodynamical investigations, comparison and combination of EOP, TRF and CRF realizations, development and 

comparison of models and software for processing VLBI observations. The IAA AC web page 

http : //m. ipa.nu. ru/PAGE/DEPFUIVD/GEO/ac-vlbi/ is supported. 

Three groups at the IAA contribute to IAA AC activity: 

1. Lab of Space Geodesy and Earth Rotation (LSGERgroup, contact maZ~in@quasar.ipa.nw.ru): 

Dr. Zinovy Malkin (Head, 30%), Elena Skurikhina (100%). The main tasks of this group are determination of longtime EOP series, station and radio source coordinates, comparison and combmation of space geodesy products. The group also maintains EOP service, space geodesy observations 

and various data bases. The group explores OCCAM and GROSS software. 

2. Group of processing of VLBI observations with the QUASAR software (former Lab of New 

Methods in Astrometry and Geodynamics, QUASAR group, contact gubanov@quasar.ipa. nw.ru): 

Prof. Vadim Gubanov (Head, NO%), Iraida Vereshagina (Kozlova) (loo%, left IAA in October 

2003), Yuriy Rusinov (50%). The main task of this group is determination of EOP, station and 

source coordinates and other astrometric and geophysical parameters using QUASAR software 

with emphasis on investigation of stochastic parameters (EOP, troposphere, clocks). 

3. Lab of Ephemeris Astronomy (LEA group, contact nuf@quusar.ipa.nw.ru): Prof. George 

Krasinsky (Head, lo%), Nadia Shuygina (20%). The main IVS related activity of this group is the 

investigations in Earth sciences and dynamical astronomy based on processing VLBI observations, 

and combining VLBI, satellite, radar and optical observations at the observational level, using 

ERA software. 

2. Analysis Activities 

2.1. LSGER Group 

The activities of the LSGER group in 2003 included: 

0 Development of the OCCAM and GROSS software used for processing of the VLBI observations. Main improvements made during the period are implementation of a new atmospheric 

loading model (data provided by GSFC is used), new TRF realization VTRF2003 with up 

dates for stations SVETLOE and GGAO, new FCN model. Many other changes with no 

significant systematic effect were made. 
IAA Analysis Center Institute of Applied Astronomy of Russian Academy of Sciences (IAA) 

Station 

ALGOPARK 

FORTLEZA 

GILCREEK 

HARTRAO 

HRAS 085 

KAUAI 

KOKEE 

MATERA 

MOJAVE12 

NRA020 

NRA085 3 

NYALES20 

RICHMOND 

WESTFORD 

WETTZELL 

0 Continued operational processing of the “24h” and intensive VLBI sessions, submitting the 

results to the IERS and IVS. Processing of the intensive sessions is fully automated. New 

EOP series iaao0307.eops and iaai0307.eopi were started. At the moment, the eops series 

contains 2792 estimates of pole coordinates, UT1 and nutation, and the eopi series contains 

4618 estimates of UT1. 

0 24-yeax session station coordinates, baseline lengths, and tropospheric parameters (ZTD, 

gradients) time series are obtained. Analysis of the results is in progress. In particular, ZTD 

series (one value for each session) is analyzed. Long time ZDT behavior can be described as 

combination of seasonal term and linear drift. Some results are presented in Table 1. The 

comparison with meteodata series is also made [4]. 

Table 1. Parameters of WZD time series. 

Nobs 

429 

622 

929 

459 

480 

345 

859 

382 

447 

173 

374 

328 

646 

830 

1584 

Time span 

1992.4-2003.8 

1993.3-2003.8 

1984.5-2003.8 

1986.0-2003.8 

1980.5-1990.8 

198 7.5-1 994.2 

1993.4-2003.8 

1990.7-2003.8 

1983.4-1992.6 

1995.1-2000.4 

1989.2-1996.6 

1994.7-2003.7 

1984.0-1992.6 

1984.0-2003.8 

1981.3-2003.8 

Bias, 

mm 

84.8f 2.5 

250.6f1.7 

52.0f 1.1 

95.3f3.2 

84.3f5.2 

80.7f3.1 

89.8f1.2 

99.3f2.4 

54.0f3.5 

72.9f4.5 

92.9f2.7 

40.0f1.2 

201 .lf3.9 

83.9f2.8 

81.5fl.2 

Drift, 

mm/year 

-1.4f0.8 

-1.0f0.6 

0.7f0.2 

2.1f0.5 

2.1 f 1.8 

2.35 1.7 

0.3f0.4 

0.7f1.3 

-2.9f4.3 

2.5f1.4 

1.9f0.4 

5.5f1.5 

1.7f0.5 

-0.1f0.2 

-0.2f0.6 

Ann. amp., 

mm 

60.9f0.9 

56.4f2.4 

42.3f 1.3 

58.3f3.3 

5.2f4.1 

27.3f2.8 

19.1f1.7 

42.3f2.7 

13.3f3.3 

33.2f4.9 

44.4f4.2 

28.3f1.5 

46.5f4.0 

18.0f3.2 

27.4f1.4 

0 24-year session station coordinates time series in the SINEX format is prepared for the IVS 

Baseline Length Pilot Project. 

0 Investigation of nutation series available in the IVS data base was continued. Corrections 

to the IAU2000 precession in longitude and obliquity have been estimated, and a new FCN 

model is proposed [2]. 

was continued [3]. 

8500 X band NGS files and more than 10,000 X and S databases are stored. 

0 Comparison of European baseline length variations derived from VLBI and GPS observations 

0 Support of IAA data base of VLBI observations and products. At the moment more than 

2.2. QUASAR Group 

In 2003 software QUASAR was prepared for processing all observations made during 1979-2003 

to improve terrestrial and celestial reference systems and EOP [l]. New database of observations 

in the QUASAR format was created. The special features of this database are: 

192 IVS 2003 Annual Report 
t 

Institute of Applied Astronomy of Russian Academy of Sciences (IAA) IAA Analysis Center 

1. Using special graphic system of QUASAR, the diurnal trends of clock for all stations were 

reduced to general quadratic model. 

2. The series, containing more than 2000 observations (e.g. VLBA, BB023), were shared in several subseries, each containing less than 2000 observations. This allows us to process observations 

with limited computing resources. 

All observations had preliminary processing, new evaluations of autocovariance functions of 

stochastic signals such as WTD fluctuation, clock instability, and UT1 variation were obtained. It 

was proved that the Least Squares Collocation (LSC) method gives estimates of signals that are 

stable with respect to uncertainty of their a priori covariance functions. The efficiency of database 

correction is demonstrated inFigure 1. One can see that two subseries of CONT94 program give 

very close LSC-estimates of WTD coinciding with the direct WVR measurements. 

10 

5 

0 

20 21 22 23 24 25 26 

Figure 1. LSC-estimation of WTD at Oda with comparison of two subseries (thick and thin lines) and 

WVR-measurements (bullets). 

During January-September 2003 estimates of total tropospheric path delay were submitted to 

the IVS Troposphere Pilot Project. 

2.3. LEA Group 

A combined analysis of VLBI and SLR measurements at the observation level is carried out 

for improving the accuracy and time resolution of EOP. Both SLR and VLBI observations are 

processed by the same software ERA, using the same astronomical constants and models for 

different kinds of measurements. 

At the first stage condition equations for VLBI and SLR observations are obtained from independent processing of each technique. For VLBI measurements zenith component of troposphere 

delay and its gradients are adjusted as stochastic signals for each day of observation. Both CCF 

ordinates of quasars and site coordinates are not improved in this solution. For SLR data we 

used laser ranges to geodetic satellites LAGEOS (Ll), LAGEOS 2 (L2), and Etalon 1&2 (E). The 

short arc technique with the arc length of 7 days is applied to all the SLR measurements to adjust 

orbital parameters along with radiation pressure coefficient, and along track acceleration, which 

are considered as non-stochastic. 

At the second stage the SLR and VLBI condition equations are mixed to determine corrections to parameters mentioned above along with five Earth rotation parameters. Kalman filtering 

procedure is used to solve the system of condition equations. Combining SLR and VLBI measureIVS 2003 Annual Repart 193 
IAA Analysis Center Institute of Applied Astronomy of Russian Academy of Sciences (IAA) 

ments on one day arcs makes it possible to improve the standard deviations of pole coordinates 

in comparison with those obtained by each technique separately. Table 2 illustrates corrections 

to the Earth orientation parameters w.r.t. the EOP(IERS)C04 and their formal uncertainties obtained from different sets of observations for daily intervals. Applying Kalman filtering method 

also allows us to derive EOP variations with subdiurnal periods. 

Table 2. Corrections to EOP(C04) and formal uncertainties obtained from different sets of observations. 

3. Outlook 

Plans for the coming year include: 

0 Improvement of algorithms and software for processing of VLBI observations. In particular, 

0 Continue regular computation of EOP series, station coordinates, and troposphere parame0 Obtain a preliminary results of global analysis of the VLBI data with QUASAR software. 

0 Continue investigations of VLBI EOP, station coordinates, and troposphere delays series. 

0 Continue to support data base of VLBI observations and products. 

implement the IMF and/or VMF mapping function(s). 

ters with OCCAM software. Submit the results to IVS and IERS. 

References 

Gubanov, V. Project: Global analysis of 1979-2003 VLBI data. Presented at the Journeks 2003, St. Petersburg, Russia, Sep 22-25, 2003. 

Malkin, Z. M. Comparison of VLBI nutation series with the IAU2000A model. Presented at the Journeks 

2003, St. Petersburg, Russia, Sep 22-25, 2003. 

Skurikhina, E., N. Panafidina, Y. Sokolova. GPS and VLBI Baseline Length Variations Presented at the 

Journeks 2003, St. Petersburg, Russia, Sep 22-25, 2003. 

Skurikhina, E. Long time ZTD series for some stations. To be presented at the 3rd IVS General Meeting, 

Ottawa, Canada, Feb 9-11, 2004. 

194 IVS 2003 Annual Report 
Istituto di Radioastronomia-Eblogna Italy CNR Analysis Center 

Italy CNR Analysis Center Report 

M. Negusini 

Abstract 

This report mmmarks the work of the Italy CNR VLBI Analysis Center. It will give fundamental 

information about the structure of the center, its locations, and its activities. 

1. Introduction 

The Italy CNR VLBI data center is the joint effort of: 

a) the Istituto di Radioastronomia (Institute of Radio Astronomy IRA) of the Consiglio 

Nazionale delle Ricerche (CNR) located in Bologna, where the research activity is carried out, 

both in radio astronomy and geodesy, and the two VLBI antennas in Medicina (near Bologna) and 

Noto (in Sicily) are managed; 

b) and in its section located in Matera at the Center of Spatial Geodesy (of the Italian Space 

Agency), where its main research activity in geodesy is carried out, and a VLBI antenna, a laser 

ranging telescope, a permanent GPS receiver and a PRARF3 antenna are located. 

The IRA has started to analyze VLBI geodetic databases from 1989, using a CALC/SOLVE 

package on the HplOOO at the Medicina station. In the following years that software was installed 

on an HP360 workstation and later on an HP715/50 workstation. We have analyzed here mostly 

databases with some European baselines, generally at least three. Most of the databases have 

been reprocessed in Bologna (using CALC and SOLVE). We are now using CALC9.1 and f-solve 

for data analysis. However, we are also storing all the databases with the Ny-hsund antenna 

data. During 2002 and 2003, we have stored in Matera all the 2000-2003 databases available on 

the IVS data centers. All the databases have been processed and saved with the best selection 

of the parameters for the final arc solutions. At present, the main analysis activity and storage 

is concentrated in Matera, where we store and analyze single databases, using CALC/SOLVE 

software. We are using F-solve regularly updated. 

2. Data Analysis and Results 

The main computer in Bologna is HP 785/B2600 workstation and its internet address is 

boira3.ira.cnr.it. At present we have installed and tested on this machine the Mark-5 VLBI Analysis Software Calc/Solve under Fortran90 compiler. In Matera the main computer is an HP282 

workstation with internet name hpj.itis.mt.cnr.it. Here, we have installed f-solve (with a center 

name of ITISCNR,) and we are using it for the analysis of single experiments and also for global 

solutions in order to compute the positions and velocities of European stations. 

Until June 2003, we continued to participate in the IVS Pilot Project -Tropospheric Parameters, 

dedicated to test and evaluate future provision of additional operational products by IVS. Regular 

submissions of tropospheric parameters (wet and total zenith delays, horizontal gradients) of all 

IVS-R1 and IVS-R4 24hr VLBI sessions were solicited. Starting with July 2003 the combined 

tropospheric estimates are regular IVS products within the TROP Project and our Analysis Center 

continued the submission of the estimated tropospheric parameters on a regular basis. In order 

IVS 2003 Annual Report 195 
Italy CNR Analysis Center Istituto di Radioastronomia-Bologna 

to fulfill the request of the project, we modified the CALC/SOLVE software, so that it is able to 

produce the Sinex files containing the tropospheric parameters in the suitable format. 

Moreover, we imported and analyzed all the other 2000-2003 databases available on the IVS 

data centers, in order to compute the tropospheric parameters. We are carrying out a comparison 

between the VLBI tropospheric estimates and the GPS-derived troposphere for the co-located 

sites. 

We are continuing to work using external tropospheric zenith path delays in order to improve 

the repeatability of the VLBI geodetic results. We are inserting the wet zenith path delays in the 

VLBI databases as if this information had been derived using a water vapor radiometer. These 

data have been inserted into the VLBI databases using an updated version of DBCAL. We are 

testing the results on the IVS-R1 and IVS-R4 databases. 

196 IVS 2003 Annual Report 
Institute of Geodesy and Geophysics/University of Technology. Vienna IGG Analysis Center 

Vienna IGG Special Analysis Center Annual Report 2003 

Harald Schuh, Johannes Boehm, Thomas Hobiger 

Abstract 

Since July 2003 the combined tropospheric parameters determined at IGG (Schuh and Boehm, 2003 

[4]) are regular n'S products provided by the IVS Data Centers one month after the availability of each 

new session database. Additionally. a forthcoming project within IVSTROP has been initialized that 

is dealing with the combination of long time series of tropospheric parameters derived from VLBI for 

climate studies. The IGG has continued its research on the determination of ionospheric parameters 

from VLBI data. 

1. General Information 

The IVS Special Analysis Center at the Department of Advanced Geodesy of the Institute 

of Geodesy and Geophysics (IGG) is part of the University of Technology, Vienna. It is mainly 

engaged in atmospheric research (troposphere and ionosphere) and the development of the VLBI 

software package OCCAM. 

Figure 1. Members of the IVS AC at IGG, Vienna (from left G. Estermann, S. Todorova: H. Sehuh, 

J. Boehm, and T. Hobiger). The picture was taken at the Working Meeting on European VLBI in Leipzig, 

Germany. 

2. Staff 

Personnel at IGG associated with the IVS Special Analysis Center in Vienna are Harald Schuh 

(Head of Department of Advanced Geodesy. Member of IVS Directing Board) and the research 

assistants Johannes Boehm and Thomas Hobiger. While Johannes Boehm is mainly concentrating 

on tropospheric resarches, Thomas Hobiger focuses on the ionosphere. They are supported by 

several student assistants. 

IVS 2003 Annual Report 197 
IGG Analysis Center Institute of Geodesy and Geophysics/University of Technology, Vienna 

3. Current Status and Activities 

10.2,- 

Modification of the VLBI software package OCCAM 

Together with Oleg Titov (Geoscience Australia), chairman of the 'OCCAM Group', and 

several other scientists from various countries, IGG is involved in the development of the 

OCCAM software. In particular, it is in charge of the classical least-squares approach using 

the Gauss-Markov model. In 2003, new tropospheric mapping functions based on data 

from numerical weather models have been implemented (Isobaric Mapping Functions IMF 

(Niell, 2001 [3]) with a priori hydrostatic gradients, and the Vienna Mapping Functions VMF 

(Boehm and Schuh, 2004 [l])). 

IVS Tropospheric Parameters: IVS-TROP 

Since July 2003 the combined tropospheric parameters determined at IGG (Schuh and 

Boehm, 2003 [4]) are regular IVS products provided by the IVS Data Centers one month after 

the availability of each new session database. The combination is done with submissions revceived from seven IVS Analysis Centers and it includes a detailed statistical analysis. Additionally, a forthcoming project within IVS-TROP was initialized that is dealing with the combination of long time series of tropospheric parameters for climate studies. More information 

about IVS-TROP can be found at the webpage http : //www. hg. tuwien. ac . at/"ivstrop . 

Vienna Mapping Functions VMF 

El 

10.19 

10.18 

10.17 

10.16 

10.15 

10.14 

10.13 

10.12 

- 

- 

- 

- 

- 

- 

- 

- 

10.11 I I I I I I 

1980 1985 1990 1995 2000 2005 

Figure 2. Hydrostatic mapping functions from NMF and VMF for an elevation angle of 5 degrees 

at Wettzell since 1984. 

198 IVS 2003 Annual Report 
4. FbturePlans 

Institute of Geodesy and Geophysics/Uniwrsity of Technology, Vienna - IGG Analysis Center 

In 2003, much effort was put into the development of new tropospheric mapping functions 

based on data from numerical weather models. On the one hand data fiom the ECMWF 

(European Centre for Medium-Range Weather Forecasts) was used to determine the parameters of the Isobaric Mapping Functions IMF (Niell, 2001 [3]), on the other hand the Vienna 

Mapping Functions VMF (Boehm and Schuh, 2004 [l]) were developed at IGG. Figure 2 

shows the comparison of the VMF with the NMF (Niell, 1996 [2]) at station Wettzell, Germany since 1984. More information about the mapping functions based on data from the 

ECMWF can be found at http://wu.hg.tuvien.ac.at/'ecmuf . 

In March 2003 a project entitled "VLBIonos", funded by the Austrian Science Fund (FWF) 

was launched. The project aims at the determination of ionospheric parameters by VLBI 

and comparsion with other techniques like GPS or Topex/Poseiden. 

It is a well known fact that in geodetic VLBI the observations are performed at two distinct 

fiequencies (2.3 and 8.4 GHz) in order to determine ionospheric delay corrections. This allows us to gain information from VLBI observables about the sum of electrons (total electron 

content - TEC) along the ray path through the ionosphere. Because VLBI is a differential 

technique only the differences in the behavior of the propagation media over the stations 

determine the leading signs and the absolute values of the observed ionospheric delays. However, there is an instrumental delay offset per baseline that shifts the measurements by a 

constant value. This offset is thought to be independent of the azimuth and elevation in 

which the ante- point and this allows us to separate the ionospheric parameters for each 

station from the ionospheric offsets per baseline in a least-squares adjustment process. First 

tests using Fourier coefficients up to 4th order plus a constant value and a linear trend rep 

resenting the vertical TEC (VTEC) were already made by Kondo (1991, [5]). Slant TEC 

(STEC) values are converted into VTEC values by a mapping function. The disadvantage 

of this approach is the assumption that these values are assigned to the station coordinates 

but not to the geographical coordinates of the intersection point of the ray path and the 

infinite thin ionospheric layer. Some problems may occur due to the apparent negative TEC 

values corresponding to the trigonometric approach. This effect can be avoided by a second approach developed at IGG using piecewiselinear functions having only positive values. 

This functional model was improved further to an adaptive piecewiselinear approach which 

fits the length of each time interval to the density of the observations. Figure 3 shows a 

comparison between the results obtained by VLBI and by different GPS analysis centers for 

24 hours at Fortaleza, Brasil. In addition to the functional model a stochastical model was 

developed, that takes the elevation angle of each observation into account. The precision of 

the estimated values is about 2-3 TEC units (TECU). These results agree within 3-10 TECU 

with other techniques like GPS (Hobiger, 2003 [6]). 

0 Determination of ionospheric parameters - Vienna TEC Model (VTM) 

For the year 2004 the plans of the IVS Special Analysis Center at IGG include: 

0 Further development of OCCAM, e.g. the estimation of radio source coordinates, 

0 Research on new tropospheric gradient models that are based on numerical weather data, 

0 Participation in the new IVS Pilot Project - Baseline Lengths, 

IVS 2003 Annual Report 199 
IGG Analysis Center Institute of Geodesy and Geophysics/University of Technology, Vienna 

FORTALEZA, Jan. 16'h 2001 90 r 

- GPS -CODE 

GPS - ESA 

GPS - JPL 

80 

70 

60 

- 

3 

Po 

E 40 

30 

20 

10 

O' -5 0 5 10 15 time [UT] 

Figure 3. VTEC over the station Fortaleza, Brasil, comparison between VLBI (Vienna TEC Model - thick 

line; Kondo approach - thick dotted line) and individual GPS solutions (from IGS). 

0 Combination and analysis of long time series of tropospheric parameters with respect to 

climate variations, 

0 Determination of total electron content (TEC) maps from VLBI. 

References 

Boehm, J., and H. Schuh: Vienna Mapping Functions in VLBI analyses, Geophys. Res. Lett., 31, 

L01603, doi:10.1029/2003GL018984,2004. 

Niell, A.E.: Global mapping functions for the atmosphere delay at radio wavelengths, J. Geophys. Res., 

Niell, A.E.: Preliminary evaluation of atmospheric mapping functions based on numerical weather 

models, Phys. Chem. Earth, 26, 475-480, 2001. 

Schuh, H., and J. Boehm: Determination of Tropospheric Parameters Within the new IVS Pilot Project, 

In: Proceedings of the 16th Working Meeting on European VLBI for Geodesy and Astrometry, held 

at Leipzig, May 9-10,2003, edited by W. Schwegmann and V. Thorandt, Bundesamt fur Kartographie 

und Geodiisie, Frankfurt/Leipzig, 257 - 264, 2003. 

Kondo T.: Application of VLBI data to measurements of ionospheric total electron content, Journal 

of the Communications Research Laboratory, Vol. 38, No. 3, 613-622, Tokyo, Japan, 1991. 

Hobiger T., J. Boehm, S. Todorava, and H. Schuh: The project "VLBIonos" - how VLBI contributes to 

ionospheric research In: Proceedings of the 16th Working Meeting on European VLBI for Geodesy and 

Astrometry, held at Leipzig, May 9-10, 2003, edited by W. Schwegmann and V. Thorandt, Bundesamt 

fur Kartographie und Geodasie, Fkankfurt/Leipzig, 291 - 298, 2003. 

101B2, 3227-3246,1996. 

200 IVS 2003 Annual Report 
Jet Propulsion Laboratory, California Institute of Technology JPL Analysis Center 

JPL VLBI Analysis Center IVS Annual Report for 2003 

Chris Jacobs 

Abstract 

This report describes the activities of the JPL VLBI Analysis Center for the year 2003. We continue 

to do celestial reference frame, terrestrial referenw frame, and sjncecraft navigation work using the 

VLBI technique. ?facking the two Mars Exploration Rova spacecraft was the highlight for the year. 

We continued improvements in the first sub-milliarcsecond global celestial reference frames at K-band 

(24 GHz) and Q-band (43 GHz). The K-band catalog more than doubled in size from 108 to 230 

SOUrceS. 

1. General Information 

The Jet Propulsion Laboratory (JPL) analysis center is located in Pasadena, California. Like 

the rest of JPL, it is operated by the CaliforniaInstitute of Technology under contract to NASA. 

JPL has had a VLBI analysis group since about 1970. Our work is focussed on supporting space 

craft 

1. 

2. 

3. 

navigation. This includes several components: 

Radio Eteference Frame (RRF) and Terrestrial Reference Frame (TFW) are efforts which 

provide infrastructure to support spacecraft navigation and Earth orientation measurements. 

Time and Earth Motion Precision Observations (TEMPO) measures Earth orientation parameters based on single baseline semi-monthly measurements. These VLBI measurements 

are then combined with daily GPS measurements as well as other sources of Earth orientation information. The combined product is used to provide Earth orientation for spacecraft 

navigation use. 

Delta differenced One-way Range (ADOR) is a differential VLBI technique which measures 

the angle between a spacecraft and an angularly nearby extragalactic radio source. This 

technique thus complements the radial information from spacecraft doppler and range measurements by providing planeof-sky information for the spacecraft trajectory. 

2. Technical Capabilities 

The JPL Analysis Center acquires its own data and supplements it with data from other 

centers. The data we acquire is taken using NASA’s Deep Space Network (DSN). 

1. Antennas: Most of our work uses 34m antennas located near Goldstone California, Madrid 

Spain, and Tidbinbilla Australia. These include the following Deep Space Stations (DSS): 

the ‘High Efficiency’ subnet comprised of DSS 15, DSS 45, and DSS 65 (see fig. 1) which has 

been the most often used set of antennas for VLBI. More recently, we have been using the 

DSN’s beam waveguide antennas: DSS 13, DSS 24, DSS 25, DSS 26, DSS 34, DSS 54 and 

DSS 55. DSS 26 and DSS 55 were used for VLBI for the first time in 2003. Less frequent use 

is made of the DSN’s 70m network (DSS 14, DSS 43, DSS 63). Typical system temperatures 

are 35K. Antenna efficiencies are typically well above 50% at X-band. 

~~ 

IVS 2003 Annual Report 201 
JPL Analysis Center Jet Propulsion Laboratory, California Institute of Technology 

Figure 1. This figure shows the three high-efficiency antennas in the subnet: Goldstone is in the center; 

Robledo, Spain is in the lower left; Tidbinbilla, Australia is on the lower right. These antennas were designed 

to have an optimum efficiency at X-band (8.4 GHz), which was to become the standard downlink frequency 

for solar-system exploration. An important secondary objective was to have a reasonable efficiency at Kaband (32 GHz) thereby allowing for possible future use at the next highest band allocated for deep space 

communications. The subnet was completed in 1986 in time for the Voyager encounter with Uranus. 

2. Data acquisition: The DSN sites have standard MkIV VLBI data acquisition systems. In 

addition we have a JPL-unique system called the VLBI Science Recorder (VSR) which has 

digital “video converters” and records directly to hard disk. The data is later transferred via 

network to JPL for correlation processing. We have purchased Mark 5 recorders and expect 

to install them within the coming year. 

3. Correlators: The JPL Block I1 VLBI correlator handles the TEMPO and RRF correlations 

of Mark IIIA format tapes. The ADOR data from the VSR systems are correlated using the 

SOFTC software correlator running on UNIX or VMS workstations. 

4. Solution types: We run several different types of solutions. For ADOR spacecraft tracking 

we make narrow field (x 10’) differential solutions. The TEMPO solutions typically have a 

highly constrained terrestrial (TRF) and celestial frame (CRF) as a foundation for estimating 

Earth orientation parameters. The RRF solves for a full TRF and CRF which is later used 

by TEMPO and ADOR. Experimental CRF work this year has focussed on modelling source 

structure. 

IVS 2003 Annual Report 202 
Jet Propulsion Laboratory, California Institute -. of Technology JPL Analysis Center 

3. StafF 

Our staff are listed below with a brief indication of areas of concentration within the VLBI 

effort at JPL. Note that not all of the staff listed work on VLBI exclusively as our group is involved 

in a number of projects in addition to our VLBI work. 

Jim Border: ADOR 

0 Sid Dains: Field support of VLBI experiments at Goldstone. 

0 Chris Jacobs: RRF and TRF 

0 Peter Kroger: ADOR 

0 Gabor Lanyi: ADOR, WVR, RRF, and TRF 

0 Steve Lowe: Software correlator, fringe fitting software 

0 Walid Majid: ADOR 

0 SumitaNmdi: ADOR 

0 Chuck Naudet: WVR, Mark IV support, and RRF 

0 Jean Patterson: ADOR 

0 Ojars Sovers: RRF and TRF. Maintains MODEST analysis code. 

0 Alan Steppe: TEMPO and TRF. 

0 L.D. Zhang: RRF 

4. Current Status and Activities 

This year’s highlight was the support of navigation for the two Mars Exploration Rovers. The 

Mars atmosphere entry point was hit to within a few hundred meters. In preparation for the 2005 

Mars mission, JPL is leading a collaboration with Goddard Space Flight center, the U.S. Naval 

Observatory, National Radio Astronomical Observatory, and the Bordeaux Observatory to extend 

the ICRF to K-band (24 GHz) and Q-band (43 GHz) (e.9. Jacobs et d, 2004). Figure 2 shows the 

current K-band CW which has more than tripled from 65 to 230 sources since last year’s report. 

A-WVR The advanced Water Vapor Radiometer (A-WVR) developed for the Cassini gravitational wave experiment, continues to be used in research applications. This device can calibrate 

water vapor induced delays with fractional stability of roughly a few parts in 1015 over time scales 

of 2,000 to 10,000 seconds. 

5. FuturePlans 

We are also in the planning stage for developing a Ka-band (32 GHz) realization of the ICFW. 

All this work is motivated by the anticipation that spacecraft navigation will require a 32 GHz 

reference frame within a few years. 

Mark 5 recorders: In 2003 we acquired Mark 5 hard disk recording systems which we hope to 

integrate into the Deep Space Network over the next year as we continue to move away from tape 

based recording. 

IVS 2003 Annual Report 203 
JPL Analysis Center Jet Propulsion Laboratory, California Institute of Technology 

K12345 

Distribution of 230 Sources 

Right Ascension (hours) 

~~ _I 

^_I ri" _L 

nrad + 

nrad 0 

nrad A 

nrad 0 

Figure 2. Celestial Reference Frame at K-band (24 GHz). There are 230 sources spread over the sky north 

of -30 deg declination. The label K12345 indicates that the frame is based on data from the 5 sessions of 

an ongoing program of observations. The shading and symbols in the legend indicate the formal declination 

precision. Note the highest precision is toward the north with precision lessening towards the south by as 

much as a factor of xtwo. This is a result of using the VLBA which is a northern array. The dotted line 

indicates the ecliptic plane. The central solid curved line indicates the galactic plane. 

6. Acknowledgements 

The research described in this paper was in part performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space 

Administration. 

References 

[l] c. S. Jacobs, P. Charlot, D. Gordon, G. E. Lanyi, C. Ma, C. J. Naudet, 0. J. Sovers, L. D. Zhang, 

and the KQ VLBI Survey Collaboration, 'Extending the ICRF to Higher bdio Frequencies: 24 & 43 

GHz,' Proceedings of IAU GA XXV Joint Discussion 16, R. Gaume & J. Souchay eds., U.S. Naval 

Observatory, Washington D.C., 2004. 

204 IVS 2003 Annual Report 
Main Astronomical Obsavatorv. National Academv of Sciences of Ukraine Andvsis Center at MA0 

IVS Analysis Center at Main Astronomical Observatory of 

National Academy of Sciences of Ukraine 

Sergej Bolotin, Yaroslav Yatskiv 

Abstract 

This report suLnrnafizes the activities of VLBI Analysis Center at Main Astronomical Observatory 

of National Academy of Sciences of Ukraine in 2003. 

1. Introduction 

The VLBI Analysis Center was established in 1994 by Main Astronomical Observatory (MAO) 

of the National Academy of Sciences of Ukraine as a working group of the Department of Space 

Geodynamics of MAO. In 1998 it started its IVS membership as an IVS Analysis Center. The AC 

MA0 is located in Central building of the observatory in Kiev. 

The primary goal of the activity of the Center is the development of the VLBI data processing 

software STEELBREEZE. From 2003 we started submissions of VLBI data analysis results to IVS. 

2. Technical Description 

The computer of the Analysis Center is a Pentium-4 1.9 GHz CPU box with 256M RAM 

and a 160 Gb HDD. It is running under Linux/GNU Operating System and is used for software 

development and VLBI data processing. 

Main Astronomical Observatory has a 56 kbps link for Internet connection. 

The STEELBREEZE software is written in the C + + programming language and uses Qt widget 

library. STEELBREEZE makes Least Square estimation of different geodynamical parameters with 

the Square Root Information Filter (SFUF) algorithm (see [l]). 

The software analyzes VLBI data (time delay) of single and multiple sets of sessions. The time 

delay is modeled according to the IERS Conventions (2003) [2], plus additional models (tectonic 

plate motion, nutation models, wet and hydrostatic zenith delays, mapping functions, etc). The 

software makes estimations of the following parameters: Earth orientation parameters, coordinates 

and velocities of a selected set of stations, coordinates of a selected set of radio sources, clock 

function and wet zenith delay. 

3. StafF 

The VLBI Analysis Center at Main Astronomical Observatory now consists of two members: 

Prof. Yaroslav Yatskiv: Head of the Department of Space Geodynamics, performs general coordination and support of activity of the Center. 

Ph.D. Sergei Bolotin: Senior research scientist of the Department of Space Geodynamics, responsible for the software development and data processing. 

IVS 2003 Annual Report 205 
Analysis Center at MA0 Main Astronomical Observatory, National Academy of Sciences of Ukraine 

4. Current Status and Activities in 2003 

This year production of two types of solutions has been started. The first type of solution, 

“global”, is based on the all available VLBI data which are suitable for determination of TRF, 

CRF and EOP and consists of estimated coordinates and velocities of stations, coordinates of radio 

sources and a series of Earth rotation parameters. In the second one, “operational”, only sessions 

from latest several years are used and Earth rotation parameters estimated in VLBI data analysis. 

The “global” solution was obtained in the end of 2003 and submitted to IVS. Almost all suitable 

VLBI observations conducted since 1979 till September 2003 were analyzed. The IERS Conventions 

(2003) [2] models have been applied in the analysis. In additional, atmospheric pressure loading 

ephemerides [3] have been used to model site displacements. Obtained TRF consists of coordinates 

of 106 and velocities of 67 stations of observations. The CRF consists of coordinates of 1571 radio 

sources. In the analysis 2654 estimates of EOP have been obtained. 

The “operational7’ solution is produced and submitted to IVS on a weekly basis since November. 

It is based on VLBI observations conducted since 2000 and analysis procedure is similar to the 

“global” one (except applying atmospheric pressure loading). In this solution only coordinates of 

stations and Earth rotating parameters are estimated. 

5. Plans for 2004 

MA0 Analysis Center will continue to take part in operational EOP determination as well as 

The development of the software STEELBREEZE will be continued next year also. 

updating the solutions of TRF and CRF from VLBI analysis of full dataset of observations. 

Acknowledgments 

The work of our Analysis Center would be impossible without activities of other components 

of IVS. We are grateful to all contributors of the Service. 

References 

[l] Biermann, G.J., 1977, Factorization Methods for Discrete Sequential Estimation, V128, Mathematics 

[2] McCarthy, D.D. (ed.), IERS Conventions (2003), IERS Technical Note 32, Observatoire de Paris, Paris. 

[3] L. Petrov, J.-P. Boy, 2003: Study of the atmospheric pressure loading signal in VLBI observations, J. 

in Science and Engineering Series, Academic Press. 

Geophys. Res., 10.1029/2003JB002500, Vol. 109, No. B?, 2004 

206 IVS 2003 Annual Report 
Observatoire de Paris, SYRTE/UMR 8630 Paris Observatory Analysis Center (OPAR) 

Paris Observatory Analysis Center-OPAR: Report on Activities, 

January - December 2003 

A.-M. Gontier, M. Feissel-Vernier 

Abstract 

In 2003 the OPAR Analysis Center activities focused, on the one hand, on the compliance of 

GLORIA software with the IAU 2000 resolutions. Various tests were performed to compare different 

ways of implementing the classical expression of the transformation from a geocentric frame to a celestial 

one. On the other hand, we analyse the impact of the celestial frame stability on the monitoring of the 

EOP. 

1. Implementation of IAU 2000 Resolutions in VLBI Analysis 

The analysis of an Earth based observation of celestial objects requires an astrometric model 

to express the transformation from a geocentric terrestrial frame to a geocentric celestial one. One 

of the resolutions adopted by the XXIV General Assembly of the IAU (Manchester, August 2000) 

recommends the use of a new approach referring to the non-rotating origin on the equator of date, 

proposed by Guinot in 1979 [lo], and using the Celestial coordinates of the CIP [3], instead of 

the classical transformation which refers to the equinox of date and uses classical precession and 

nutation quantities. In GLORIA software the update of the new paradigm and the classical one, 

based on the IAU 2000 A model for precession-nutation was made and compare together last year 

[7], [8]. Different ways of implementing the classical transformation have been investigated and 

tested with GLORIA this year. 

Based on Chapter 5 of IERS Conventions 2003 [ll], we have implemented two different ways 

of computing the Greenwich Sideral Time GST: 

0 version a: implementation of the numerical relation between GST and the Earth rotation 

angle 8 referred to the Celestial Ephemeris Origin ([ll] chapter 5, equation 35) which includes 

an update of the “equation of the equinoxes”. 

0 version b: modification of the current relationship between Greenwich Mean Sideral Time 

(GMST) and UT1 [l] to include dGMST ([ll] chapter 5, equation 37 with a constant term 

of 14600pas) due to the correction in the precession rate, together with an update of the 

“equation of the equinoxes” (1111 chapter 5, second line of equation 35). 

In order to study the impact of the frame bias at 52000 (especially the equinox o&t dao), we 

have also implemented a so-called VLBI version. It includes the usual precession parameter ([ll] 

chapter 5, equation 31), Herring’s routine for nutation “IAU2000A.f“ [ll] and the computation of 

GST using version b together with equation 47 of [4]. 

Various tests have been performed to verify the level of agreement between those three classical 

versions using the 1999 NEOS sessions. The analyses showed differences less than 0.5pas on polar 

motion, 0.lps on UT1 with a slope of 3ps/century between the a version and the others. For 

d$ sine, de the differences are less than 0.5pas between a and b version but could reach 3.5pas 

between a and the VLBI version. For the EOP the mean value of the standard errors is about 

53pas. 

IVS 2003 Annual Report 207 
Paris Observatory Analysis Center (OPAR) Observatoire de Paris, SYRTE/UMR 8630 

5 1 I I I I 1 I I 1 I I 

- X-pole Y-pole Universal time 

8 1M)uas ~ - 1oouas - - 1muas C 4- 

53 

.- tu 

c 

- 22: 5. $1 0 L+;'= I% 1 1 *- I>. : 0 -?+Ouas %I 

-0 0 

8 

0 -z z -0 7 

0 I I I I I I I I I I 1 I 

2. Improved EOP Determination 

5 

- 4 c 

3 '$ 

C 

:;: 

0 

Figure 1. Stability of pole coordinates and universal time over 1990-2002 according to source selection. All 

sources: green(1ight); stable sources only: blue (dark). 

In addition to the fact that the Allan variance is always lower when using the stable sources 

only, a striking feature for x-pole is that the use of the stable sources cancels the random walk 

208 IVS 2003 Annual Report 
Observatoire de Paris, SYRTE/UMR 8630 Paris Observatory Analysis Center (OPAR) 

noise appearing beyond one-year sampling time when using all sources. The reference to the stable 

sources ensures or strengthens white noise in the long term for the measurement of polar motion. 

The measurement of universal time involves the stability of both the terrestrial and the celestial 

reference frames. The possible influence of the terrestrial frame on the remaining random walk 

signature beyond one year should be investigated. 

Nutation is the motion of the Earth’s axis in space in response to the torque exerted by the 

Moon, Sun and planets. The state of the art model recommended by the IAU in 2000 [13], is based 

on i) the modelling of the astronomical external torque at the 0.1 pas accuracy level 1141 [15], ii) 

the modelling of the response of the non rigid Earth to this external torque, and iii) the VLBI 

observations relative to extragalactic directions materialized by the quasars. When observed at the 

current level of precision (a fraction of a milliarcsecond), no object is really point-like. Apparent 

motions, if existing, may be related to the existence of jets originating in the sources. Such motions 

may give rise to time varying inhomogeneities in the celestial reference frame that, in turn, could 

mimic nutation signals. 

Studying the influence on nutation of the variable torque exerted by the atmosphere and the 

ocean, Dehant et al. [5] showed that apparent variability in the celestial frame can lead to changes 

in estimates of precession or long period nutation coefficients at a level comparable to that of the 

variable nutation excited by the Earth’s fluid layers (a few tens of pas). 

Figure 2 shows the celestial frame effect on precession and obliquity rate and on the 18.6 year 

nutation term. The precession and obliquity rates changed by 20 pas/year and the 18.6 year 

prograde component by 30 pas. 

(a) Precession and oblqurty rate (b) Prograde 18.6 years (b) Retrograde 18.6 years 

I I I I I I 

I I I 

-20 

-40 

-60 

-+ 

Def + Cand 

-1 00 w dPsi/dt (uada) 

Def + Cand + DefiQing 

9- + 

Stable sources 11 @ 

Allsources 

In phase 

I All sources 

- 50 

-0 

- -50 

I I I I I 1 I I I I I I 

-60 40 -20 0 0 50 100 0 50 100 

Figure 2. Precession and obliquity rate corrections (left graph) and prograde and retrograde corrections to 

the 18.6 year nutation term in pas (right graph). 

3. Summary 

The update of the GLORJA software to comply with the IAU 2000 resolutions was made. 

The comparisons between the different implementations of the classical transformation showed an 

agreement better than 4pas on estimated EOP. 

M. Feissel-Vernier [6] proposed a source selection scheme based on time series analysis of source 

coordinates that gives the possibility to detect unstable sources. The consideration of the stable 

IVS 2003 Annual Report 209 
Paris Observatory Analysis Center (OPAR) Observatoire de Paris, SYRTE/UMR 8630 

sources strengthens white noise in the long term for the measurements of polar motion. The impact 

on UT1 is less sensible as the measurement involves also the stability of the terrestrial frame. The 

improved stability and internal consistency of the frame impacts positively the determination of 

Earth orientation parameters. 

References 

[l] S. Aoki, Guinot, B., Kaplan, G.H., Kinoshita, H., Mc Carthy, D.D. & Seidelmann, P.K., 1982. The 

[2] J.A. Barnes, 1967. NBS Report 9284. 

[3] N. Capitaine, 1990. Celest. Mech., 29, 335-360. 

[4] N. Capitaine, Wallace, P.T., McCarthy, D.D., 2003. Expressions to implement the IAU 2000 definition 

[5] V. Dehant, Feissel-Vernier, M., de Viron, O., Ma, C., Yseboodt, M., & Bizouard, C., 2003. JGR, 108 

B5, 2275. 

[6] M. Feissel-Vernier, 2003. Selecting stable extragalactic compact radio sources from the permanent 

astrogeodetic VLBI program. A&A, 403, 105. 

[7] A.-M. Gontier, 2002. An implementation of IAU 2000 resolutions in VLBI analysis software. IERS 

Technical Note 29, eds. Capitaine et al., Verlag BKG Frankfurt, 71-75. 

[8] A.-M. Gontier, Feissel-Vernier, M., Essaifi, N., 2003. Paris Observatory Analysis Center OPAR: Report 

on Activities, January - December 2002, International VLBI Service for Geodesy and Astrometry 2002 

Annual Report, NASA/TP-2003-211619, N.R. Vandenberg and K.D. Baver eds., p.273-276. 

[9] A.-M. Gontier, & Feissel-Vernier, M., 2003. Contribution of stable sources to ICRF improvements, in 

IAU XXV, Joint Discussion 16, 22 july 2003, Gaume, Mc Carthy and Souchay eds., in press. 

[lo] B. Guinot, 1979. In Time and the Earths Rotation, eds. D.D. McCarthy and J.D. Pilkington, D. Reidel 

[ll] IERS Conventions (ZOOO), http://maia.usno.navy.mil/conv2003.html 

[12] Ma, C., 2003. Private communication. 

[13] P.M., Mathews, Herring, T.A., & Buffett, B.A., 2002. JGR, 107, 1029. 

[14] J., Souchay, & Kinoshita, H., 1996. A&A, 312, 1017. 

[15] J., Souchay, & Kinoshita, H., 1997. A&A, 318, 639. 

New Definition od Universal Time. A&A, 105, 359-361. 

Of UT1. A&A, 406, 1135-1149. 

Publ., 7-18. 

210 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO) Analysis Center 

The IVS Analysis Center at the Onsala Space Observatory 

Rudiger Haas, and Ham-Georg Scherneck 

Abstract 

We give a brief overview of the activities of the IVS Analysis Center at the Onsala Space Obsentatory 

during 2003. Some examples of achieved results and ongoing analyses related to earth rotation, loading 

phenomena, and atmospheric research are preaented. 

1. Introduction 

The IVS Analysis Center at the Onsala Space Observatory (OSO) is active in research concentrating on a number of particular topics that are relevant to space geodesy and geosciences. These 

research topics are important for geodetic VLBI and are investigated using VLBI observations and 

corresponding analysis programs. In the following we will briefly address some of these topics and 

present some examples of performed and ongoing analyses. For the future we plan to continue 

VLBI related research along those lines, concentrating on particular research topics. There are no 

plans at OS0 for a routine analysis of global VLBI data in a service sense. 

2. Earth Rotation Variations and ENSO 

We analysed the combined IVS time series of earth orientation parameters [l] to study ElNiiio/Southern Oscilation (ENSO). The IVS UT1 values were processed similar to the description in [2] and using the effective atmospheric angular momentum functions as calculated from 

NCEP/NCAR reanalyses [3]. The resulting excess length-of-day (dLOD) values are shown in Figure 1 together with the Multivariate ENSO Index (MEI) [4]. There is a clear correlation between 

the two time series and both clearly show the ENSO events during the last 23 years. 

1.51 I I I I I I I I I I I I I I I I I I I I I I I I 1 4 

1 -2 h 

E X 

0.5 -0 4 

--2% 

9 .- c 

- 

00 

rn 

- > 

-0.5 -4 

Figure 1. Lower blue curve, left scale: Excess in length of day (dLOD) in ms derived from combined IVS 

EOP values [l]. Top red curve, right scale: Multivariate ENSO index (MEI) [4]. Both time series clearly 

show the ENSO events during the last 23 years. 

IVS 2003 Annual Report 21 1 
Onsala Space Observatory (OSO) Analysis Center Onsala Space Observatory (OSO) 

3. High-frequency EOP During CONT02 

We analysed the CONT02 VLBI observations and determined polar motion and UT1 values 

with a time resolution of 1 hour. Figure 2 displays the time series and their corresponding spectra. 

Variations with 12 hour and 24 hour periodicity are detectable both in polar motion and UT1. A 

variation with an 8 hour period is detected marginally above the significance limit in Yp. Further 

investigations are ongoing. 

-1 ' 

-1.5' " ' ' ' ' ' ' ' ' ' ' ' ' ' ' 

16 18 20 22 24 26 28 30 

days in October 2002 

I" 

1 oo IO1 1 o2 

period in hours 

UTI 

I 

-1.5 -I/ 

16 18 20 22 24 26 28 30 

days in October 2002 

1 o2 

1 oo 

1 oi

1 od ; 1 o1 1 o2 

period in hours 

1. 

0.5 . 

0. 

-0.5 ' 

-1 . 

16 18 20 22 24 26 28 30 

days in October 2002 

I 'I ' 48'hr. ' 

I , 241hr. ! 

1 o2 ,12,hr. p, , 

I., , , , ,t 1 o-~ I 

1 oo IO' 1 o2 

period in hours 

Figure 2. Polar motion and UT1 for CONT02. Upper plots in red: time series of Xp (left column), Yp 

(middle column) and UT1 (right column) with a time resolution of 1 hour. Lower plots in blue: spectra of 

the above time series. Periods of 8, 12, 24, and 48 hours are indicated with red vertical lines. 

4. Ocean Tide Loading and Atmospheric Loading 

The automatic ocean tide loading provider [5] has been maintained during 2003. On the website 

http://www.oso.chalmers.se/-loading users can chose between 11 different ocean tide models that 

are available to calculate ocean tide loading parameters for site positions that can be specified 

interactively. The parameters are provided in several formats, and are sent to the user via e-mail. 

Time series of atmospheric loading predictions that are based on global convolution of atmopheric pressure fields are available for most of the VLBI databases since 1990 on the website 

ht t p: / / www .oso.chalmers.se/ - hgs/apload/apload. ht ml. 

5. European Crustal Motion 

The analysis of the purely European geodetic VLBI observations has continued and results for 

crustal motion have been published in 2003 [SI. 

212 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO) Analysis Center 

0- 

6. Atmospheric Parameters at Onsala During CONT02 

Additionally to the CONTO2 VLBI observations we performed simultaneous observations with 

the Onsala IGS permanent GPS equipment, two water vapor radiometers (WVR), and a rain 

radar (FtR) at the observatory. The water vapor radiometer Astrid was operated in sky mapping 

mode, while the water vapor radiometer Konrad followed the VLBI observation schedule and 

was perfoming tipcurve measurements during slewing times of the VLBI telescope. Figure 3 

shows preliminary results for the zenith wet delay (ZWD) derived from observations with the four 

collocated techniques. These prelimiary results show a reasonably good agreement between the 

ZWD derived from the different techniques and have been communicated the EGSAGU-EUG 

Joint Assembly 2003 [7] and the 16th Working Meeting on European VLBI for Geodesy and 

Astrometry [8]. However, the rain radar measurements indicate that there are still some WVRdata that were influenced by rain and should be removed from the time series. Furthermore, there 

are still some unexplained biases and thus the investigations are continuing. 

.. 1 .. . * 

L- IY I I Y I .it1 I< I 

:* 

i 

WVR-K 

WVR-A 

VLBI 

GPS 

7. Trends in Tropospheric Water Vapor at Onsala 

We investigated trends in the tropospheric water vapor content based on ZWD data determined 

from observations with the three collocated techniques VLBI, GPS, and WVR at Onsda and 

radiosondes (Rs) at Landvetter airport 37 km away fiom the observatory. Data for more than 23 

years are available from VLBI, WVR and RS, while GPS data are available since 1993. Each of 

the techniques has specific advantages and disadvantages in terms of stability and time resolution. 

Therefore, a combination of the results of the individual techniques appears to be a promising 

approach. We developed strategies to assess trends in tropospheric water vapor and to combine 

the results of the four independent techniques in order to determine robust results that can be 

useful for climate related research [9]. 

IVS 2003 Annual Report 213 
Onsala Space Observatory (OSO) Analysis Center Onsala Space Observatory (OSO) 

8. Activity in the IVS Pilot Project - Tropospheric Parameters 

We continued our activity in the IVS Pilot Project - Tropospheric Parameters. Tropospheric 

parameters for all VLBI stations observing in the IVS R1 and R4 networks were submitted to 

the IVS. Figure 4 shows histograms of the ZWD for four stations that are located in different 

climate zones: Ny-hesund - polar, Wettzell - temperate, Hartrao - dry, Fortaleza - tropical. A 

dependence of the amount of water vapor on the climate zone is obvious. 

5 20050rl~moKl IEljl

2 40 5 100 $ 40 I) 150 

100 

50 

0 

0 200 400 0 200 400 0 200 400 0 200 400 

ZWD (mm) ZWD (mm) ZWD (mm) ZWD (mm) 

Figure 4. Histograms of zenith wet delay (ZWD) values for four stations located in four different climate 

regions. The histograms include results from the IVS R1 and R4 experiments during 2002 and 2003. 

References 

[l] Steinforth, C., and Nothnagel, A.: Official IVS EOP results, Combined series IVS03Q3 

[2] Gipson, J. M., and Ma, C.: Signature of El Nino in length of day as measured by VLBI. IERS(1998) 

[3] Salstein, D. A., and Rosen, R. D.: Global momentum and energy signals from reanalysis systems. 

[4] Wolter, K.: Multivariate ENS0 Index (MEI) webpage http://www.cdc.noaa.gov/-kew/MEI/mei.html 

[5] Scherneck, H.-G., and Bos, M.: Ocean Tide and Atmospheric Loading. In: N. R. Vandenberg and 

K. D. Baver (Eds.): IVS 2002 General Meeting Proceedings, NASA/CP-2002-210002,205-214, 2002. 

[6] Haas, R., Nothnagel, A., Campbell, J., and Gueguen, E.: Recent crustal movements observed with the 

European geodetic VLBI network: Geodetic analysis and results. Journal of Geodynamics, 35(4-5), 

doi: 10.1016/S0264-3707(03)00003-6,2003. 

[7] Haas, R., Gradinarsky, L., Elgered, G., and Johansson, J.: Studying atmospheric properties at the 

Onsala Space Observatory during the CONT02 experiment. Geophys. Res. Abstr., Vol. 5, 09604,2003. 

[8] Elgered, G., and Haas, R.: The Geodetic VLBI Network Station at the Onsala Space Observatory 

- Activities During 2002. In: W. Schwegmann and V. Thorandt (Eds.): Proc. of the 16th Working 

Meeting on European VLBI for Geodesy and Astrometry, Bundesamt fur Kartographie und Geodbie, 

61-66, 2003. 

[9] Haas, R., Elgered, G., Gradinarsky, L., and Johansson, J.: Assessing Long Term Trends in the Atmospheric Water Vapor Content by Combining Data From VLBI, GPS, Radiosondes and Microwave 

Radiometry. Proc. of the 16th Working Meeting European VLBI for Geodesy and Astrometry, W. 

http://giub.geod.uni-bonn.de/vlbi/IVS-AC/combi-all/HTML/start .html 

Technical Note No 26. 

Preprints, 7th Conf. on Climate Variations, American Meteorological Society, Boston, MA, 344-348. 

I 

I Schwegmann and V. Thorandt (eds.), Bundesamt fur Geodikie und Kartographie, 279-288,2003. 

IVS 2003 Annual Report 

1
SHAO, Chinese Academy of Sciences Shanghai Astronomical Observatory Analysis Center 

Shanghai Astronomical Observatory Analysis Center Report 

Jinling Li 

Abstract 

Our activities in the calender year 2003 are involved in the coordination of the VLBI observations 

for the Asia-Pacific Space Geodynamics (APSG) program, data archives and reduction and application 

studies. Our plans for the calender year 2004 will be mainly focused on the application of VLBI to the 

positioning of spacecraft. 

1. General Informat ion 

As one of the research groups of the Center for Astrogeodynamics Research, Shanghai Astre 

nomical Observatory (SHAO), we focus our activities on studies of Radio Astrometry and Celestial 

Reference Frames. Facilities for us to analyze the astrometric and geodetic VLBI observations are 

the HF' C180 Workstation, several sets of personal computers with advanced technical specifications, as well as several sets of SUN Workstations in the computer division of SHAO. We use 

CALC/SOLVE system in the routine VLBI data reduction. The members involved in the IVS activities are Jinling Li, Guangli Waug, Bo Zhang, Li Guo, Nianchuan Jian, Ming Zhao and Zhihan 

Qian. 

2. Current Activities 

2.1. Observation Coordination and Data Reduction 

Our group continue the coordination of the VLBI experiments as well as the observation 

archives and reduction for the Asia-Pacific Space Geodynamics (APSG) program. In October of 

2003 two 24h VLBI sessions were carried out. We also participated in some IERS/IVS campaigns 

aimed at comparisons of reference frames and/or Earth Rotation Parameters. We contributed to 

IERS several sets of global solutions from VLBI data reduction. 

2.2. Modelling the Residual Clock Behavior in VLBI Data Reduction 

Based on the observations and simulated data, the feasibility of the periodic function modelling 

(P-model) of the residual clock behavior in the routine VLBI data reduction was discussed. Two 

global solutions of 1,567 VLBI sessions from 1990 to 2001 were performed corresponding to the 

continuous piecewise linear modelling (N-model) and the P-model of the residual clock behavior. 

It is shown that compared with the N-model the number of unknowns in the solution could be evidently decreased and so the degree of freedom increased when the P-model was used. Though the 

formal errors of the coordinates of stations and sources as well as the Earth Orientation Parameter 

are on the same level, it is slightly better to model the residual clock behavior by the P-model 

than the N-model. The formal errors of coordinates could be decreased for more than 80% of the 

stations and 70% of the radio sources (Figure 1 and Figure 2). 

IVS 2003 Annual Report 215 
Shanghai Astronomical Observatory Analysis Center SHAO, Chinese Academy of Sciences 

I -1 

A=N-P 

mean(A6J=0.01 (mm) 

mean(A6y)=0.01 (mm) 

mean(A6>=0,03(mm) 

-0 05 0 J 0 20 40 BO 80 

sequence number of stdims 

Figure 1. A comparison of the formal errors of the - 

station coordinates between the P- and N-model of 

the residual clock behavior 

A=N-P Difference in as vs a Difference in as vs S 

I 4.. * . -. -. 

NMI m 

I I I 

0 100 200 300 -50 0 50 

Right ascension (deg.) Declination (deg.) 

Figure 2. A comparison of the formal errors of the 

radio source coordinates between the P- and N-model 

of the residual clock behavior 

2.3. Solutions and Analysis of EOP High Frequency Variation 

To get the solutions of the EOP high frequency variation in a piecewise manner, we could use 

piecewise continuous linear modelling with constraints on the change of the rate between connected 

pieces. By doing so the solutions to the rates could be strongly correlated with each other and the 

real change in the rate may be concealed. We have tried to solve for the means of EOP within 

every piece without any constraints. Comparisons show that if the data points are sufficient the 

constraints are not necessary. Figure 3 shows our solutions to the high frequency variation of EOP 

and its wavelet analysis. Y mmp.(mas) UTI-TAI (msec) 

2, , too, 

0 

0 200 400 

Epoch (hour) 

4 4 

8 8 

16 16 

32 32 

64 64 

128 128 

256 256 

0 200 400 0 200 400 

Epoch (hour) Epoch (hour) 

Figure 3. An example of the solutions and analysis of the high frequency variation of EOP 

216 IVS 2003 Annual Report 
__- SHAO, Chinese Academy of Sciences Shanghai Astronomical Observatory Analysis Center 

I 

c 

I 

2.4. Some Other Activities Related with the Chinese CHANGE Project 

The angular resolution in spacecraft positioning by the intended Chinese VLBI network was 

analyzed in order to provide some quantitative reference specifications to the feasibility demonstration and the program design of the Chinese CHANGE project. 

Table 1 liits the angular resolution estimations by shifting the spacecraft geocentric distance, 

the constraint of range, the configuration of station network and the type of observations. The 

spherical coordinates of the spacecraft are cr = 105" and 6 = 35". In Table 1, the site code 

from 1 through 7 represent respectively the VLBI stations of SHANGHAI, URUMQI, KUNMING, 

BEIJING, KASHIMA, SVETLOE and HAFCTEBEESTHOEK, a, and a6 represent respectively 

the angular resolution in the right ascension and declination, uCorr" is the correlation coefficient 

between the two estimations. From Table 1 it could be concluded that (1) either T or i could be 

used independently in the spacecraft positioning, if T and i observations are used in combination 

in the positioning the precision of the resulting angular resolution is better than only using one 

of the two types observations; (2) if only i observations are used without the range constraint, 

the angular resolution in right ascension and declination are strongly correlated with each other 

and 50 result in a low precision of estimation; (3) in the combination use of T and i observations 

the latter contributes to a very limited extent to the improvement of the precision; (4) the range 

constraint obviously improves the angular resolution; (5) the intended Chinese VLBI network is 

longer in east-west baseline than in north-south, the corresponding longitudinal angular resolution 

is better than the latitudinal; (6) if the Chinese network is supplemented with some international 

stations when tracking the spacecr&, the angular resolution could be improved significantly. 

Taking into consideration the inclination angles among the lunar orbit, equatorial and ecliptic 

planes, Figure 4 and Figure 5 demonstrate the estimation of angular resolutions for the intended 

Chinese network only and for the Chinese network supplemented by some international stations. 

The target distance is 380,000km, only delay observations are used with lkm range constraint and 

uT = Ins. The comparison of the two figures shows that with the supplement of international stations the sky coverage with high resolution is extended and the resolution is improved significantly. 

Figure 4. Angular resolution estimation with Ins delay observation 380, OOOkm target lkm range constraint 

and four (1 to 4) tracking stations 

IVS 2003 Annual Report 217 
Shanghai Astronomical Observatory Analysis Center SHAO, Chinese Academy of Sciences 

Table 1. Angular resolution estimation from VLBI observables 

r = 180,OOOlcm Without constraint llcm range constraint 

Site code Data type Angular resolution(mas) Angular resolution(mas) 

ua ag Corr ua 06 Corr 

1 to 4 7 18.0 21.1 0.16 17.2 19.2 0.33 

i 4290.8 21556.2 -0.99 533.7 413.4 -0.34 

7, i 17.2 19.1 0.33 17.2 19.1 0.33 

1 to 7 7 6.5 4.4 -0.09 6.3 4.4 -0.10 

i 134.1 485.3 -0.46 129.2 274.6 -0.44 

7, i 5.3 4.4 -0.09 5.2 4.4 -0.09 

r = 380,000h Without constraint llcm range constraint 

Site code Data type Angular resolution(mas) Angular resolution(mas) 

ucr a6 Corr ua 06 Corr 

1 to 4 7 18.4 21.5 0.16 17.5 19.5 0.34 

i 5119.4 19386.1 -0.99 539.7 347.3 -0.36 

7, i 17.6 19.6 0.32 17.5 19.5 0.34 

1 to 7 7 6.7 4.4 -0.08 5.0 4.4 -0.12 

i 128.0 379.9 -0.42 125.4 124.7 -0.71 

7, i 5.9 4.4 -0.08 4.9 4.4 -0.12 

Figure 5. Angular resolution estimation with Ins delay observation 380, OOOkm target lkm range constraint 

and seven (1 to 7) tracking stations 

3. Plans for the Calendar Year 2004 

We will continue to deliver our efforts on the coordination of the APSG program as well as on 

the response to various IERS and IVS campaigns of regional and global VLBI data analysis. We 

will focus most of our efforts on the application of VLBI to the positioning of spacecraft. 

218 IVS 2003 Annual Report 
United States Naval Observatory USNO VLBI Analysis Center 

U.S. Naval Observatory VLBI Analysis Center 

David A. Boboltz, Alan L. Fey, David M. Hall, Kerry A. Kingham 

Abstract 

This report summarizes the activities of the VLBI Analysis Center at the United States Naval 

Observatory for calendar year 2003. Over the courae of the gear, Analysis Center personnel analyzed 

biweekly diurnal experiments with designations IVSRl and NSR4 for use in-house and continued 

timely submission of IVSR4 databases for distribution to the IVS. In addition, Analysis Center personnel analyzed and submitted databases for Celestial Reference Frame (CRF) experiments: CRF-17 

through CRF-24, CRF-MS7, and CRF-DS5 through CRF-DS9. During the 2003 calendar year, the 

USNO Analysis Center produced two periodic global Terrestrial Reference Fhme (TRF) solutions with 

designations usn2003a and usn2003b. Earth orientation parameters based on these solutions, updated 

by the did (IVSR1 and IVSR4) experiments, were submitted to the IVS. The VLBI Analysis Center personnel at USNO completed ICRF Extension 2, and produced global CRF solutions designated 

crf2003a and crt2003b. This report also describes activities planned for the 2004 calendar year. 

1. Introduction 

The USNO VLBI Analysis Center is supported and operated by the United States Naval 

Observatory (USNO) in Washington, DC. The primary services provided by the Analysis Center 

are the analysis of diurnal experiments, the production of periodic global Terrestrial Reference 

Frame (TRF) and Celestial Reference Frame (CRF) solutions, and the submission to the IVS 

of session-based Earth orientation parameters (EOP-S) based on USNO global TFU? solutions. 

Analysis Center personnel maintain the necessary software required to continue these services to 

the IVS including periodic updates of the GSFC CALC/SOLVE software package. In addition 

to operational VLBI analysis, USNO personnel engage in research aimed at developing the next 

generation ICFU?. Information on USNO VLBI analysis activities may be obtained at: 

http://rorf.usno.navy.mil/vlbi/. 

I 

I 

2. Current Analysis Center Activities 

2.1. Experiment Analysis and Database Submission 

During the 2003 calendar year, personnel at the USNO VLBI Analysis Center continued pre 

cessing of diurnal (WS-R1 and IVSR4) experiments for use in internal USNO global TRF and 

CRF solutions. USNO is also responsible for the timely analysis of the WS-R4, and the resulting 

databases are submitted within 24 hours of correlation for dissemination by the IVS. In addition, 

Analysis Center personnel continue to be responsible for the analysis and database submission for 

the periodic IVS-CRF experiments. The primary goal of these experiments is the densification of 

ICRF sources in the Southern Hemisphere. In 2003, USNO scheduled and analyzed 14 CFU? experiments including CRF-17 through CRF-24, CRF-MS7, and CRF-DS5 through CRF-DS9. The 

analyzed databases were submitted to the IVS for dissemination to the community. 

IVS 2003 Annual Report 219 I 

1 
USNO VLBI Analysis Center United States Naval Observatory 

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 

MJD - 2450083 (Jan 01 1979) 

- 20 2 w.r.m.s. = 0.2390342355 E 

VI 10 

z 

v 

E 

I 

0 

z 

cc 

3 

6 

x -20 

0 

-10 

0 

a 

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 

MJD - 2450083 (Jan 01 1979) 

Figure 1. Differences between pole positions estimated from the usn2003b TRF solution and the IERS-C04 

time series. A weighted least squares linear fit to the data and the weighted RMS are shown in the upper 

right corner of each plot. 

2.2. Global TRF Solutions and EOP Submission 

USNO VLBI Analysis Center personnel continued to produce periodic global TRF solutions 

(usn2003a and usn2003b) over the course of the 2003 calendar year. All USNO global TRF solutions 

including the most recent solution may be found at: 

http: //rorf .usno .navy.mil/solutions/. 

Session-based Earth orientation parameters derived from these TRF solutions were compared 

to those derived from GSFC periodic TRF solutions and with the IERS-C04 time series prior to 

submission to the IVS. Figure 1 shows an example of the comparison information available at the 

220 IVS 2003 Annual Report 
United States Naval Observatorv USNO VLBI Analvsis Center 

Name 

David A. Boboltz 

Alan L. Fey 

David M. Hall 

Kerry A. Kingham 

web site mentioned above. In this figure, differences in pole position estimates derived from the 

usn2003b solution and the IERSC04 time series are plotted. 

EOP-S based on the global TRF solutions were continuously updated with new data from the 

IVSRl/R4 experiments prior to the introducition of the next global solution. These updated 

EOP-S files were submitted to the IVS twice weekly within 24 hours of the experiment correlation. 

Analysis Center personnel also worked to produce suitable SINEX format files based on the 24hr 

experiments for the IVS Pilot Program to produce a combination for a Time Series of Baseline 

Lengths by the group at UBOnn. 

Responsibilities 

Quarterly global TFU? solutions, solution comparisons, web page design and administration, VLBI data analysis. 

Quarterly global CRF solutions, solution comparisons, web page design and administration, VLBI data analysis. 

VLBI data analysis and database submission, IVS EOP submission. 

Correlator interface, VLBI data analysis 

2.3. Global CRF Solutions and ICRF-Ext.2 

During the calendar year 2003, personnel at the USNO VLBI Analysis Center completed work 

on Extension 2 of the ICW, and a paper reporting the results has been submitted. The primary 

objective of ICRF-Ext.2, is to provide positions for extragalactic radio sources observed since the 

definition of the ICRF (July 1995) and its first extension (April 1999) and to refine the positions of 

candidate and other sources using additional observations. The data added to the ICFU? in ICWExt.2 spanned May 1999 through May 2002 and was obtained from both geodetic and astrometric 

observing programs coordinated through the IVS. Approximately 1.2 million new observations 

from approximately 400 sessions were added along with 50 new sources. For the first time, data 

from the Very Long Baseline Array (VLBA) experiments with the designation RDV were included. 

The 30 station RDV experiments added over 652,000 delay observations (-20% of the total number 

of delays) to the solution. 

During 2003, Analysis Center personnel continued work on global CRF solutions including 

crf2003a and crf2003b. These solutions were compared to the current ICRF. As an example, 

Figure 2 shows the differences between USNO CRF2003b source positions and the corresponding 

ICRF-Ext.2 positions. 

3. StafF 

The staff of the VLBI Analysis Center is drawn from individuals who work at the USNO. The 

staff and their responsibilities are: 

4. Future Activities 

For the upcoming year January 2004-December 2004, USNO VLBI Analysis Center personnel 

plan to accomplish the following activities: 

0 Continue the processing of biweekly IVS-R1/R4 experiments for use in internal TRF and 

IVS 2003 Annual Report 221 
USNO VLBI Analysis Center United States Naval Observatory 

CRF2003B minus ICRF-Ext.2 

360 330 300 270 240 210 180 150 120 90 60 30 0 

Right Ascension (degrees) 

Plot contains 212 sources with >= 0 observations and f.e. <= 0.100E+24 arcseconds 

ofey 22-Jon-2004 16:lS 

Figure 2. Differences in the source positions as derived from the USNO CRF2003b solution and the ICRFExt.2 solution. Plotted are all 212 defining sources of the ICRF. The dotted line represents the galactic 

equator. The differences are due primarily to the fact that the ICRF defining source positions have not 

changed since the definition of the ICRF. 

CRF global solutions. 

Continue the submission of databases for IVS-R4 experiments for dissemination by the IVS. 

Continue the analysis and database submission for all IVS-CRF experiments. 

Continue the production of periodic global TRF solutions and the submission of EOP-S 

estimates to the IVS updated by the IVS-Rl/R4 experiments. 

Begin the submission of Sinex format files based on USNO databases for dissemination by 

the IVS. 

Begin the submission of EOP-I estimates based on the intensive experiments to the IVS. 

Begin the analysis of intensive experiments for use in USNO internal EOP-I time series 

estimates. 

Continue the production of periodic global CRF solutions. 

Make additional astrometric observations in the Southern Hemisphere in collaboration with 

ATNF partners. 

222 IVS 2003 Annual Report 
U. S. Naval Observatory USNO Analysis Center for Source Structure 

I 

USNO Analysis Center for Source Structure Report 

Alan L. Fey, David A. Boboltz, Ralph A. Gaume, Kerry A. Kingham 

Abstract 

This report summarizes the activities of the United States Naval 0bse.rvatory Analysis Center for 

Source Structure for calendar year 2003. International Celestial Reference F'rame (ICRF) source were 

observed using the Very Long Baseline Array (VLBA) at 24 GHz and 43 GHz as part of a program 

to extend the ICRF to higher radio kequencies. Experiments BR079C and BL115A were calibrated 

and imaged. A program to measure apparent jet velocities from the motions of source components 

using 8.4 GHz VLBA images continued. A total of 60 sources have been analyzed to date. A Southern 

Hemisphere imaging and astrometry program for maintenance of the ICRF continued. Imaging of 69 

southern hemisphere ICFU? sources at 8.4 GHz was completed. Activities planned for the year 2004 

include continued model fitting and imaging of ICFW sources at standard and higher frequencies as 

well as continued research into the effects of intrinsic source structure on astrometry. 

1. Analysis Center Operation 

The Analysis Center for Source Structure is supported and operated by the United States Naval 

Observatory (USNO). The charter of the Analysis Center is to provide products directly related to 

the IVS determination of the "definition and maintenance of the celestial reference frame." These 

include, primarily, radio frequency images of ICRF sources, intrinsic structure models derived from 

the radio images, and an assessment of the astrometric quality of the ICRF sources based on their 

intrinsic structure. 

The web server for the Analysis Center is hosted by the USNO and can be accessed by pointing 

your browser to 

http: //rorf .usno.navy.mil/ivssaac/ 

The primary service of the analysis center is the Radio Reference Frame Image Database 

(RRFID), a web accessible database of radio frequency images of most ICRF sources with declination greater than about -30 degrees. Source structure information is provided in the form of 

synthesis images and source models suitable for evaluating sources for astrometric and/or geodetic 

use and for long-term monitoring of sources. The RRFID contains 3060 Very Long Baseline Array 

(VLBA) images of 452 sources at radio frequencies of 2.3 GHz and 8.4 GHz. The RItFID can be 

accessed from the Analysis Center web page or directly at 

http://unr.usno.navy .mil/RRFID/ 

A recent addition to the WID are VLBA images of ICRF sources at radio frequencies of 

24 GHz and 43 GHz. The WID contains 578 images of 230 sources at these frequencies. 

2. Current Activities 

2.1. VLBA High Frequency Imaging 

VLBA observations to extend the ICRF to K-band (24 GHz) and Q-band (43 GHz) continued in 

2003. These observations are part of a joint program between the National Aeronautics and Space 

Administration, the USNO, the National Radio Astronomy Observatory (NRAO) and Bordeaux 

IVS 2003 Annual Report 223 
USNO Analysis Center for Source Structure U. S. Naval Observatory 

0 0 N :: N 

P“ v) s 

- - - Mean: 0.46 mop 

Median: 0.28 mas 

P‘“ 

a 

::o 

c e‘“ 

Meon: 0.76 mas 

Median: 0.61 mas 

Meon- 1.68 mos 

Median: 1.23 mos 22 2z 

z’ 5 2 

0 Lo 0 

0 0 0 

0 1 2 3 4 0 1 2 3 4 

compment Angulor Separation from Core (mos) Component Angular Separation from Core (mas) Component Angulor Seporotion from Core (mas) 

Figure 1. Distribution of Gaussian component angular separation from the assumed core component for the 

28 common sources observed on 2002 Jan 16 and 2002 May 15 at a) 8.4 GHz, b) 24 GHz and c) 43 GHz. 

The core is defined as the model component fitted to the image having the smallest angular size. 

Observatory. The long term goals of this program are to 1) develop higher frequency reference 

frames for improved deep space navigation, 2) extend the VLBA calibrator catalog at K/Q-band, 

3) provide the benefit of the ICRF catalog to new applications at these higher frequencies, and 

4) study source structure variation at K/Q-band in order to improve the astrometric accuracy. 

During the calender year 2003, two VLBA high frequency experiments (BR079C and BL115A) 

were calibrated and imaged. 

Gaussian component models fitted to selected images show that the sources are generally more 

compact as one goes from the ICRF frequency of 8.4 GHz to 24 GHz. This result, shown in 

Figure 1, suggests that reference frames defined at higher radio frequencies will be less susceptible 

to the effects of intrinsic structure than the ICRF. 

The distribution of “Structure Index” calculated from the first epoch of K/Q-band images 

(Charlot 2002, private communication) is shown in Figure 2. Also shown are values for the 28 

sources observed in RDV31 at X-band which overlap with these sources. Note the shift toward 

lower values as the frequency of observation increases. 

qz----j a) 8.4 GHz 

VI W 

0.- 30 

m 

? 

L 

L 

01 

n 

Z 

0 

1 

1234 

VI 

0 

m 

0 

0 

VI W 

30 

m or? 

? 

0 

1 234 

Structure Index Structure Index Structure Index 

Figure 2. Distribution of “Structure Index” for sources at a) 8.4 GHz, b) 24 GHz, and c) 43 GHz. A total 

of 65 sources were observed at 24 and 43 GHz on 2002 May 15 (BR079A). Also shown are the values for 

the 28 overlap sources observed at 8.4 GHz on 2002 Jan 16 (RDV31). 

2 24 IVS 2003 Annual Report 
U. S. Naval Observatory USNO Analysis Center for Source Structure 

The BL115A experiment was conducted as a 24 GHz survey in order to obtain a better idea of 

the number of ICRF sources detectable at this frequency. Of the 249 sources observed, there were 

sdicient data to image a total of 184 sources. As an estimate of the compactness of the sources 

a core fraction, defined as the ratio of core flux density to total flux density, was calculated. Core 

flux density is defined as the CLEAN-ed flux density in an image contained within one synthesized 

beam. The total flux density is defined as the total CLEAN-ed flux density (i.e., the sum of 

all CLEAN model components). The distribution of source core fraction versus source total flux 

density is shown in Figure 3. As can be seen in this figure, the weaker sources appear to be more 

compact (but this may just be a selection effd). 

01 I I1 

0.2 0.5 1 2 5 10 

Source Flux Density (Jy) 

Figure 3. The distribution of source core fraction (ratio of core flux density to total flux density) versus 

source total flux density. Core flux density is defined as the CLEAN-ed flux density in an image contained 

within one synthesized beam. The total flux density is defined as the total CLEAN-ed flux density (i.e., the 

sum of all CLEAN model components). 

2.2. Motions of Source Components 

VLBA observations for maintenance of the celestial and terrestrial reference frames have been 

carried out since about 1994. Since 1997, these VLBA RDV observations have been part of a 

joint program between the USNO, Goddard Space Flight Center (GSFC) and the NRAO. Images 

produced from VLBA RDV observations are made available through the RRFID. 

A joint program between Whitier College and the USNO to measure apparent jet velocities 

from the motions of source components using WID data at 8.4 GHz was initiated by Piner et al 

(2002, AAS, 200, 4501). To date, a total of 60 sources have been analyzed (Piner et al. 2003, 

AAS, 203, 9207). Results show that the distribution of apparent component speeds peaks at low 

apparent speed for all components is 4.8~. 

1 

I values (near IC, where c is the speed of light) but extends to values as high as 30c. The average 

I 

I IVS 2003 Annual Report 225 
USNO Analysis Center for Source Structure U. S. Naval Observatory 

Name 

Alan L. Fey 

David A. Boboltz 

Ralph A. Gaume 

Kerry A. Kingham 

2.3. ICRF Maintenance in the Southern Hemisphere 

The USNO and the Australia Telescope National Facility (ATNF) are collaborating in a continuing VLBI research program in Southern Hemisphere source imaging and astrometry using 

USNO, ATNF and ATNF-accessible facilities. These observations are aimed specifically toward 

improvement of the ICRF in the Southern Hemisphere. Plans include strengthening the ICRF in 

the Southern Hemisphere by a) increasing the reference source density with additional S/X-band 

bandwidth-synthesis astrometric VLBI observations, and b) VLBI imaging at 8.4 GHz of ICRF 

sources south of 6 = -20". 

VLBI images for a total of 69 Southern Hemisphere ICRF sources were made at a frequency of 

8.4 GHz using the Australian Long Baseline Array (Ojha, et al. 2004, in preparation). The images 

were used to calculate a core fraction, i.e., the ratio of core flux density to total flux density, 

for all observed sources. The resulting distribution, with a mean value of 0.83, suggests that 

most sources are relatively compact. However, just over half the observed sources show significant 

extended emission in the form of multiple compact components. These sources are probably poorly 

suited for high accuracy reference frame use unless intrinsic structure can be taken into account. 

Many of the observed sources have never been previously imaged at milliarcsecond resolution. 

Responsibilities 

Primary scientific contact, Web and data base design and content, 

Webmaster, Web server administration, VLBA data analysis (imaging), structure analysis 

VLBA data analysis (imaging), structure analysis 

Liaison to the ICRF Product Center of the IERS 

Web and data base design and content, Webmaster, Web server administration, geodetic data analysis (imaging), Mark 4 interface to 

imaging software, structure analysis 

3. Staff 

The staff of the Analysis Center is drawn from individuals who work at the USNO. The staff 

and their responsibilities are: 

4. Future Activities 

The Analysis Center currently has a program of active research investigating the effects of 

intrinsic source structure on astrometric position determination. Results of this program are 

published in the scientific literature. 

The following activities for 2004 are planned: 

0 Continue imaging and analysis of VLBA 2.3/8.4 GHz experiments 

0 Continue imaging and analysis of VLBA 24/43 GHz experiments 

0 Make additional astrometric and imaging observations in the Southern Hemisphere in collaboration with ATNF partners 

226 IVS 2003 Annual Report 

York University and SGL/CRESTech Canadian TD Center 

I 

Canadian VLBI Technology Development Center 

Anthony Searle, Calvin Klatt, Mario B6rutd 

Abstract 

The Canadian Technology Development Center has developed an "end-to-end" geodetic VLBI S~S 

tem built on S2 equipment. The development of this system has led to an operational IVS network. 

Development work continues to streamline operations and improve S2 instrumentation. 

1. Introduction 

The Canadian VLBI Technology Development Center is a collaborative effort of the Space 

Geodynamics Laboratory (SGL), the Geodetic Survey Division of Natural Resources Canada 

(GSD/NRCan) and the Dominion Radio Astrophysical Observatory (DRAO) of the Herzberg 

Institute for Astrophysics of the National Research Council of Canada, (DRAO/HIA/NRC). 

2. S2 VLBI Geodesy 

The S2 VLBI observation program continued in 2003 as the operational "E3" IVS observing 

network. The "E3" Network consists of Algonquin, Yellowknife, the Canadian Transportable VLBI 

Antenna (CTVA), Kokee observatory, and the Bansportable Integrated Geodetic Observatory 

(TIGO) located in Concepcion Chile. Yellowknife and Kokee were not scheduled to observe in 

all twelve sessions, but split the year to ensure a four-station network for all sessions. The small 

network size limited the contribution to EOP determination. 

3. S2 VLBI Data Acquisition System (SZDAS) 

The S2 VLBI data acquisition system is being jointly developed by SGL and GSD. The S2-DAS 

is designed to accommodate up to four VLBA/Mark IV-type single sideband baseband converters 

(BBCs), each with a local oscillator (LO) independently frequency switchable under computer 

control. The objective of the development of the S2-DAS is to enable high sensitivity group delay 

measurements without appealing to a more costly parallel IF/baseband sub-system. 

A sixth network DAS has been prepared for use at the Svetloe antenna, and is expected to be 

in place in the spring of 2004. 

The DAS Operating System (DASOS) has seen extensive development in the past few years. 

Further software development continues to improve robustness and efficiency. New algorithms for 

automatic gain control and status monitoring are currently being tested and will be included in 

the next official release. Due to reduced personnel at SGL, hardware support for the S2-DAS was 

moved to the laboratories at GSD. 

4. S2 VLBI Correlator 

The Canadian Correlator is a six station correlator (expandable to ten stations) using S2 

playback terminals and is designed to handle S2 frequency switched bandwidth synthesis data. 

~ ~~~ 

IVS 2003 Annual Report 229 
Canadian TD Center York University and SGL/CRESTech 

Recent activity has focussed on the development of visualization and statistical analysis software 

to enhance system performance monitoring. 

Maintenance of the playback terminals was completed in early 2003. A large backlog of VSOP 

observations was given priority as the HALCA mission came to an end. Correlator staff was cut 

to one person as a result of the end of HALCA operations. It is expected that the S2 correlator 

will apply to become an IVS Correlator in 2004. 

5. Canadian Transportable VLBI Antenna (CTVA) 

The CTVA is a 3.6m radio telescope acquired to facilitate densification of the terrestrial reference frame in remote regions. The antenna will be collocated with GPS elements of the Canadian 

Active Control System (CACS) to provide fiducial station positions. The GSD is responsible for 

CTVA system development. 

Figure 1. CTVA positioned in St. John's, Newfoundland. 

The CTVA spent all of 2003 in St. John's, Newfoundland. During the spring of 2003, the 

Kvarz CH1-75 maser received a new crystal oscillator, as a short term replacement the CTVA was 

able to produce results using a passive maser. CTVA uses a group of local university and college 

students for all observing operations. 

As an operational antenna in an IVS network, the CTVA will apply to become an IVS Network 

Station in 2004. 

6. S2 Geodetic Experiment Scheduling, Operations and Analysis 

Due to the small size of the E3 network contributions to EOP determination were limited. 

Results of the few &station E3 sessions were presented at the April 2003, IVS Analysis workshop 

230 IVS 2003 Annual Report 
York Universitv and SGL/CRESTech Canadian TD Center 

in Paris. With the larger network, E3 results were shown to be comparable to the R4 network. 

This work included simulations that indicated a 5-station S2 network that included Svetloe could 

produce EOP uncertainties that are at the level of the IVS R4 network. These results have lead 

to the inclusion of Svetloe in the E3 Network in 2004. 

The analysis component of the Canadian Technology Development Center will apply to become 

an IVS Analysis Center in 2004. b 

I IVS 2003 Annual Report 231 
Technology Development Center at CRL Kashima Space Research Center, Communications Research Laboratory 

Technology Development Center at CRL 

Tetsuro Kondo 

Abstract 

Communications Research Laboratory (CRL) has led the development of VLBI technique in Japan 

and has been keeping high activities in both observations and technical developments. This report 

gives a review of the Technology Development Center (TDC) at CRL and summarizes recent activities. 

1. TDC at CRL 

Communications Research Laboratory (CRL) has published the newsletter “IVS CRL-TDC 

News” twice a year in order to inform the world about the development of VLBI related technology 

in Japan as an IVS Technology Development Center. The newsletter has been published twice 

a year. One of them is published as proceedings of the symposium held at the Kashima Space 

Research Center every autumn. The newsletter is available through the Internet at following URL 

http:/ /www.crl.go.jp/ka/radioastro/tdc/index.html. 

2. Staff Members of CRL TDC 

Table 1 lists the staff members at CRL who are involved in the VLBI technology development 

center at CRL. 

Table 1. Staff Members of CRL TDC as of December, 2003 (alphabetical). 

Name (Last, First) 

Ichikawa, Ryuichi 

Kawai, Eiji 

Kimura, Moritaka 

Kondo, Tetsuro 

Koyama, Yasuhiro 

Kuboki, Hiromitsu 

Nakajima, Junichi 

Osaki, Hiro 

Sekido, Mamoru 

Takeuchi, Hiroshi 

Works 

Delta VLBI 

Antenna system 

Giga-bit e-VLBI 

e-VLBI 

e-VLBI, analysis softwares 

Antenna system 

Giga-bit e-VLBI 

FS9, e-VLBI 

Delta VLBI 

Antenna system, and e-VLBI 

3. Recent Activities 

3.1. Geodetic VLBI using K5/VSSP system[’] 

The first 24-hour geodetic observation using the K5/VSSP (IP-VLBI) system was carried out 

on the Kashima-Koganei baseline on January 31, 2003. Observations were also carried out by using 

the K4 system and the gigabit VLBI system in parallel with the K5 system for system verification 

232 IVS 2003 Annual Report 
Kashima Space Research Center, Communications Research Laboratory Technology Development Center at CRL 

K4Z5 

I I I I I I 

t 1 

Offrrt = 176 ppct 

RMS = 72.7 pnc 

0 5 10 15 jo 

Houn born 09:OO UT on Jan 31.2003 

RS-Gm 

z7000 7 

-t 1 

25ooo- Offset = 26071 pstc 

REds = 171 3 prec 

5 10 15 m 

Houn from 09 00 UT onJan 31.2003 

-0 

Figure 1. Differences of group delays obtained from K4, K5, and gigabit VLBI systems. 

by comparing each result. Fig. 1 shows results of differences of group delays observed by each 

system. An offset seen in the comparison result between K4 and K5/VSSP denotes the difference 

of the instrumental delay of each system. The standard deviation of data variation is consistent 

with that predicted from signal to noise ratio. It is therefore concluded that the K5/VSSP has no 

fatal defect. Long term variations of the scale of several hours or more seen in the results between 

K5 and gigabit system (GBR) are considered as the characteristics of the gigabit system against 

the change of ambient temperature. The K4 and the K5/VSSP systems are multi-channel (i.e., 

band splitting) systems while the gigabit system is a single channel (i.e., full band) system. In the 

case of multi-channel system, phase calibration signals injected in each channel cancels out delay 

variations commonly appearing in the both systems such as the effect of temperature variations. 

Long term variations are usually treated as a clock behavior in a baseline analysis, 50 that it does 

not affect positioning accuracy seriously. 

I 

, 

3.2. US-Japan e-VLBI for a Rapid UT1 

We attained the shortest record of time to obtain UT1 in collaboration with MIT Haystack 

Observatory team. We succeeded in UT1 measurement in less than 24 hours from the observation 

start by means of eVLBI conducted on the Kashima (K5)-Westford (Mark 5) baseline on June 25, 

2003. Times required for observations, data transfer, format conversion, correlation processing, 

and UT1 analysis (including bandwidth synthesis) were 2 hours, 4 hours, 4 hours, 12 hours, and 1 

hour, respectively. 

3.3. Delta e-VLBI for Spacecraft Po,itioni~~~31~4~~51~6] 

We carried out a series of delta VLBI observations of "NOZOMP, a Japanese spacecraft exploring Mars, under cooperation with the VLBI community in Japan using the K5/VSSP system 

during the period just before the last earth swing-by (June 19, 2003) to cruise to Mars. Measurements of group delay were carried out and it was confirmed by a closure test that an accuracy 

of nanosecond order was achieved. Although the baseline lengths are not long (a few hundreds 

kilometers) the accuracy of spacecraft positioning of 300 mas was attained in spite of the use of 

low intensity and narrow-band (< IMHz) signals. To improve this accuracy ten times or more, we 

ZVS 2003 Annual Report 233 
Technology Development Center at CRL Kashima Space Research Center, Communications Research Laboratory 

are developing a technique to observe phase delay and to connect it between observation scans. 

(falcon)” that is a Japanese spacecraft launched in May, 2003 and aims at the sample return from 

an asteroid. 

Technology development of e-VLBI for spacecraft positioning is continued using the “HAYABUSA 

3.4. K5/PC-VSI Gigabit VLBI 

Using a VSI interface board (PC-VSI 2000DIM) developed in the last fiscal year, we succeeded 

in direct acquisition of 1 Gbps data with the Linux file system. Data acquisition of 2 Gbps rate 

is possible with this interface board. As the K5/PC-VSI system adopts a general-purpose PC and 

file system, it shows a remarkable affinity for the Internet compared with the Mark 5 system. A 

series of e-VLBI experiment (ftp data transfer after an observation) with the Metsahovi Radio 

Observatory (MRO), Finland was conducted as in the last fiscal year. Observations with 2 Gbps 

were carried out in June, 2003 and fringes were successfully detected by using a software correlator 

(Fig. 2). 

Development of a 16-ch sampler (ADS2000) (Fig. 3) that substitutes for DFC2000 goes well 

and is almost finished. 

ADS2000 16ch X 64Msps 

ADS1000 lch x 1024Msps A Sourcc:NRAO150 

Figure 2. 2 Gbps fringes observed 

on Kashima - Metsahovi baselline using 

K5/PC-VSI system. 

Figure 3. Ks/PC-VLBI system: PCs with PCVSI board (2TB server), a giga-bit A/D sampler (ADSlOOO), and a 16ch x 64Msps sampler 

(ADS2000). 

3.5. Practical Use of Software ~orrelator[81[9] 

Two types of software correlator have been developed at CRL. One is a software correlator 

dedicated to geodetic VLBI data processing. Real-time processing of 10 Mbps data is possible now 

by a PC. It was already used practically for the processing of “No~omi~’ VLBI observation data 

and of 24-hour geodetic VLBI session data. 

The other type of software correlator is dedicated to the processing of gigabit VLBI data. 

Real-time processing of 100 Msps (mega-samples per sec) is possible now. Network distributed 

processing system aiming at the real-time processing of 1 Gsps data is under development. 

234 IVS 2003 Annual Report 
Kashima Space Research Center, Communications Research Laboratory Technology Development Center at CRL 

Figure 4. Logomark of NICT. 

4. Coming Reorganization from CRL to NICT 

Under the "Reorganization and Rationalization Plan of Special Public Institutions" adopted at 

a Japanese Cabinet meeting held in December 2001, CRL and the Telecommunications Advance 

ment Organization of JAPAN (TAO) will be reorganized as the National Institute of Information 

and Communications Technology (NICT) on April 1, 2004. Fig. 4 shows the new logomark of 

NICT. 

References 

Koyama, Y., T. Kondo, H. Osaki, K. Takashima, K. Sorai, H. Takaba, and K. Fujisawa, Evaluation of 

the K5 system in geodetic VLBI experiments, IVS CRL-TDC News, No.23, pp.26-30, Nov. 2003. 

Koyama, Y., T. Kondo, and H. Osaki, Rapid UT1-UTC estimation from Westford-Kashima e-VLBI 

experiment, IVS CRL-TDC News, N0.22, pp.6-9, June 2003. 

Ichikawa, R, M. Swkido, H. Osaki, Y. Koyama, T. Kondo, and NOZOMI VLBI group, VLBI application for spacecraft navigation (NOZOMI) Part I -Overview-, IVS CRL-TDC News, N0.22, pp.10-11, 

June 2003. 

Ichikawa, R., M. =do, H. Osaki, Y. Koyama, T. Kondo, T. Ohnishi, M. Yoshikawa, and NOZOMI 

DVLBI group, An evaluation of VLBI observations for the positioning of the NOZOMI Spacecraft and 

the future direction in research and development of the deep space tracking using VLBI, IVS CRL-TDC 

News, No.23, pp.31-33, Nov. 2003. 

Sekido, M., R. Ichiiwa, H. Osaki, T. Kondo, and Y. Koyama, VLBI application for spacecraft navigation (NOZOMI) Part II -Delay Model and Analysis-, IVS CRL-TDC News, N0.22, pp.12-15, June 

2OO3. 

Sekido, M., R. Ichikawa, H. Osaki, T. Kondo, Y. Koyama, M. Yoshikawa, and NOZOMI VLBI Ob 

servation Group, VLBI Application for Spacecraft Navigation (NOZOMI) -follow-up on Model and 

Analysis-, IVS CRL-TDC News, No.23, pp.34-35, Nov. 2003. 

Kimura, M., J. Nakajimal, J. Ritakari, and A. Mujunen, First detection of 2-Gbps wideband fringes 

between two PCbased VLBI systems, IVS CRZ-TDC News, N0.22, pp.5, June 2003. 

Kondo, T., Y. Koyama, and H. Osaki, Current status of the K5 software correlator for geodetic VLBI, 

IVs CRL-TDC News, No.23, pp.18-20, Nov. 2003. 

Kimura, M., J. Nakajima, H. Takeuchi, and T. Kondo, 2-Gbps PC architecture and Gbps data processing in K5/PCVSI, IVS CRL-TDC News, No.23, pp.12-13, Nov. 2003. 

IVS 2003 Annual Report 235 
FFI TD Center Forsvarets forskningsinstitutt (FFI) (Norwegian Defence Research Establishment) 

FFI Technology Development Center - Software Development 

Per Helge Andersen 

Abstract 

FFI’s contribution to the IVS as a Technology Development Center will focus primarily on the 

development and validation of the GEOSAT software for a combined analysis at the observation level 

of data from VLBI, GPS and SLR. This report shortly summarises the latest improvments of the 

GEOSAT software. FFI is currently Analysis Center for IVS and ILRS, Technology Development 

Center for IVS, and Combination Research Center for IERS. 

1. The GEOSAT Software 

The advantages of the combination of independent and complementary space geodetic data at 

the observation level is discussed in Andersen ([ 11). The models of GEOSAT are listed in Andersen 

([2]). The most important changes implemented in 2003 are described in the following. 

A new major software component of GEOSAT has been developed for 3D raytracing through 

the atmosphere. A complete 3D atmospheric model provided daily by ECMWF is input to the 

software. Based on the available tracking (VLBI, GPS, or SLR) for that specific date a set of tables 

for each active station is automatically generated with information about the time delay in the 

different elevation and azimuth directions. Also statistical information concerning the variability 

of relevant parameters are extracted from the ECMWF data. This information is used in the estimation filter as time-dependent parameter constraints. No mapping functions are used anymore. 

Different interpolation schemes are under testing. A new model/parameterization for the atmospheric delay is under consideration in GEOSAT. The status is that some individual VLBI-only 

sessions have been analyzed. A clear reduction in a posteriori residuals is observed. The Grueger 

model is default for the MW refractive index and the Ciddor model is default for the optical or 

near optical wavelengths. The Ciddor model has been tested against Ciddor’s own software. 

The pressure loading tables provided by Leonid Petrov is used by GEOSAT. For stations not 

included in this table a simple pressure scaling model is used where the load scale parameter is 

automatically estimated in the analysis. A grid of reference pressure values has been derived by 

averaging the surface pressure levels provided by NCEP during the last 20 years. 

A model for thermal deformation of the VLBI antenna construction has been included. Thermal 

coefficients and thermal time delays can be estimated. 

The station eccentricity file has been checked in great detail and updated with all the most current log files of VLBI, GPS, and SLR. The eccentricity information is treated as a new observation 

type in GEOSAT in addition to the VLBI, GPS, and SLR observation types. 

The GEOSAT software calculates one set of station coordinates and velocities for a reference 

marker at a colocated station in addition to the eccentricity vector to each different antenna 

reference point. The software has been extended so that observations from several active VLBI 

systems, GPS receivers and SLR systems all will contribute to the estimation of the parameters 

for the station reference marker. The instruments could be operating either simultaneously or in 

different time windows. 

The IERS 2003 Conventions has been fully implemented including the new EOP parameteriz at ion. 

IVS 2003 Annual Report 
Forsvarets forskningsinstitutt (FFI) (Norwegian Defence Research Establishment) FFI TD Center 

The absolute GPS satellite antenna phase center table published by Rothacher recently has 

All relevant partial derivatives has been verified against numerical partial derivatives. 

In the global processing of several years of data the stable sources listed by Feissel et al. are 

automatically estimated as constants while the others are estimated as random walk parameters or 

session parameters. A set of defining stations satieing certain criteria is automatically estimated 

as constants where the other stations are estimated as constants during a certain interval (between 

one day and one month). 

been implemented as an a priori model. The parameters will be estimated during the analysis. 

1 

2. F'uturePlans 

We plan to implement an orbital overlap scheme for automatic evaluation of the orbit quality (GPS, LAGEOS). Observations from the GALILEO navigation system wil be applied when 

available. Only minor changes in GEOSAT are required for this extension. 

3. Staff 

Dr. Per Helge Andersen - Research Professor of Forsvarets forskningsinstitutt (FFI) and Instii tute of Theoretical Astrophysics, University of Oslo. 

References 

[l] Andenen, P. H. Multi-level arc combination with stochastic parameters. Journal of Geodesy 

[2] Andersen, P. H. High-precision station positioning and satellite orbit determination. PhD 

(2000) 74: 531-551. 

Thesis, NDFtE/Publication 95/01094. 

IVS 2003 Annual Report 237 
G S FC Technology Development Center NASA Goddard Space Flight Center 

GSFC Technology Development Center Report 

Ed Himwich, John Gipson, Raymond Gonzalez, Nancy Vandenberg 

Abstract 

This report summarizes the activities of the GSFC Technology Development Center for 2003. The 

report forecasts activities planned for the year 2004. The GSFC Technology Development Center (TDC) 

develops station software including the Field System (FS), scheduling software (SKED), hardware 

including tools for station timing and meteorology, scheduling algorithms, operational procedures, and 

provides a pool of individuals to assist with station implementation, check-out, upgrades, and training. 

1. Technology Center Activities 

The GSFC IVS Technology Development Center (TDC) develops hardware, software, algorithms, and operational procedures. It provides manpower for station visits for training and up 

grades. There are other technology development areas at GSFC covered by other IVS components 

such as the GSFC Analysis Center. 

The current staff of the GSFC TDC consists of Nancy Vandenberg, Ed Himwich, Chuck Kodak, 

Raymond Gonzalez, John Gipson, and Willam Wildes. 

The remainder of this report covers the status of the main areas of development that are 

currently being pursued. 

2. Field System 

During this period some new features were released in FS version 9.6: 

1. 

2. 

3. 

4. 

5. 

6. 

support for Mark 5A recorders 

support for the ATNF LBA DAS (provided by J. Quick, HartRAO) 

support for MET3 meteorological sensors with stand-alone logging independent of the FS 

available 

improved TAC support with stand-alone logging independent of the FS available 

numerous improvements in the new system temperature scheme including improved robustness 

numerous small bug fixes and improvements were added 

The new FS Linux Distributon 5 was released. This was developed with the assistance of J. 

Quick (HartRAO). This new distribution is based on the Debian “woody” distribution and includes 

up to date versions of various packages and, most importantly, current security patches. 

A new PC configuration for FS operations was defined. The most significant change in the 

configuration is that now three IDE hard disks are used instead of two SCSI disks. The change to 

IDE was possible because performance of the kernel IDE driver has improved significantly. Because 

of the cost savings in the change to using IDE drives, it is now feasible to have three disks. This 

allows a more robust “rotating” back-up scheme to be used. 

238 IVS 2003 Annual Report 
NASA Goddard Space Flight Center GSFC Technology Development center 

In the next year, several other improvements are expected, among these are: (1) integrated 

support for Mark 5A recorders including support for schedules written for Mark 5A systems, (2) 

integration of S2 DAS support (to be provided by M. Bbrub6, NRCanada), (3) &vue will become the 

primary user interface for the FS (this will allow simultaneous use of remote and local FS consoles), 

(4) support for station specific detectors in the new ONOFF program, and (5) an ANTTAB file 

generation script will be included. 

3. SKED and DRUDG 

The GSFC Technology Development Center is responsible for development, maintenance, and 

documentation of the SKED and DRUDG programs. These two programs operate as a pair for 

preparation of the detailed observing schedule for a VLBI session and its proper execution in the 

field. In the normal data flow for geodetic scheduling, first SKED is run at Operation Centers to 

make the .skd file that contains the full network observing schedule. Then the stations use the 

.skd file as input to DRUDG for making the control files and procedures for their station. During 

2003 many changes were made to both SKED and DRUDG. 

SKED had the following features added to it: 

1. SRCFLR. This allows a user to specify a target number of observations for the first N sources 

in the source list. For example, you could specify that you wanted the first 10 sources to 

each have at least 1.5% of the total number of observations. This option is useful if you have 

some sources in a session that you want to observe. For example, the RDV experiments have 

a set of core sources, and a set of sources that are scheduled periodically. It is important 

that when the later sources are scheduled that they be observed. 

2. SRCDIST. This option imposes soft constraints on the number of observations per source. 

There are four modes: NONE, UPTIME, EVEN, SQRT. 

(a) NONE imposes no constraint. 

(b) UPTIME tries to have the number of observation per source be proportional to the 

total uptime of the source. This will emphasize sources that are visible by most of the 

network. 

(c) EVEN tries to make the number of observations per source be the same for all sources. 

(d) SQRT tries to make the number of observations per source be proportional to the square 

root of the uptime. This smooths out the distribution of observations. 

3. FILL IN MODE. In a given scan typically some of the antennas will stop observing before 

others. If FILL IN MODE is turned on, SKED monitors the idle time to see if it can squeeze 

in additional observations during this idle time. 

4. BEST N. Sked was modified to choose the BEST-N sources based on observing strength and 

station geometry for a given experiment. This obviates the need for a scheduler to choose 

these sources by hand. 

Another option that was partially implemented during the latter part of 2003 was the imple1. Observe all sources frequently enough to monitor their flux density. 

mentation of an automatic source-monitoring program. There are several goals to this program: 

IVS 2003 Annual Report 239 
GSFC Technology Development Center NASA Goddard Space Flight Center 

2. Increase the number of sources used in scheduling geodetic experiments. 

3. Make the selection of the sources automatic. 

We developed a database containing a list of all the sources observed by the various member 

institutions of IVS since the inception of geodetic VLBI in 1979. For each experiment and each 

source this database contains information on the number of observations scheduled, the number 

of observations correlated, and the number of good observations. This database can be queried by 

SKED to select sources that have not been observed recently. 

Several changes were made to DRUDG to support the increasing use of Mark 5 recorders. 

These included the addition of two new modes: 

1. Mark 5A piggy back mode allows stations to record simultaneously on tapes and Mark 5A 

recorders. The tape recorder is attached to the first output of the formatter, and the Mark 

5A modules are attached to the second output. 

2. Mark 5A mode allows stations to record using the Mark 5A modules as the primary recorder. 

The Mark 5A modules are attached to both outputs of the formatter. 

3. Mark 5A pig-wire mode allows stations to record using the Mark 5A recorders as the primary 

recorder when these are attached to the second output of the formatter (same as for piggyback 

mode). 

In all of the above modes the schedules are first generated by SKED as if the experiments were 

going to be recorded on tape. Then the recorder type is changed in DRUDG. This is necessary 

because SKED is not yet Mark 5 aware. Another reason for doing it this way is that number 

of Mark 5A units increased over the course of the year. Scheduling the experiments to use tape 

seemed to be prudent. You could always change the schedule to use disk at the stations. The 

converse operation is more problematic, because SKED allocates time for tape change. If the 

experiments were scheduled to use Mark 5A recorders this time would not be allocated. 

One of the primary goals for next year include making SKED Mark 5 aware. 

240 IVS 2003 Annual Report 
MIT Haystack Observatory Haystack TDC 

Haystack Observatory Technology Development Center 

Alan Whitnex David Lapsley 

Abstract 

VLBI technology development at Haystack Observatory continues to focns on VLBI data recording and transport. With the completion of the Mark 5A disk-based data-recording system and its 

subsequent widespread deployment (-80 units now in operation), engineering eI€& are now focused 

on developing the Mark 5B, which uses the same platform and media a6 Mark SA, but whicb will 

comply with the VSI speciiication. Additionally, a major program continues to focus on e-VLBI development, including the development of VSI-E, new protocols and algorithms, paformance testing and 

monitoring, and the beginnings of routine e-VLBI transfers. 

1. Mark 5B VLBI Data System 

The Mark 5B VLBI data system is now being developed at MIT Haystack Observatory- It is 

based on the same physical platform, uses the same disk-modules as the Mark 5A, and supports the 

same maximum data rate of 1024 Mbps. However, the Mark 5B will incorporate a VSI standard 

interface and command set. The Mark 5B system may be used with a Mark 4 or VLBA dataacquisition rack with the use of simple interface electronics connecting directly to the Mark 4 or 

VLBA samplers, eliminating the need for an external formatter. For existing VLBA systems using 

VLBA formatters, the current recording limit is 512 Mbps due to formatter limitations; the use of 

a Mark 5B connected to the sampler outputs will allow the recording of 1024 Mbps. For existing 

Mark 4 systems, the Mark 5B will allow connection of all 14 BBCs to two Mark 5Bs for a total 

aggregate data rate of 1792 Mbps. A backwards compatibility path will be provided to allow 

disks recorded on the Mark 5B system to be replayed on a Mark 5A system with the output in 

VLBA tapetrack format. This will allow existing Mark 4 correlators to process Mark 5B data. 

An upgrade to existing Mark 5A systems will be made to implement this compatibility path. 

In addition, the Mark 5B is being designed to emulate all critical functionality of the Mark 

4 Station Unit, so that the Mark 5B may be directly connected to a Mark 4 correlator through 

a simple interface without the use of a Mark 4 Station Unit. This will allow existing Mark 4 

correlators to inexpensively expand the number of stations they support. Prototype Mark 5B 

systems are expected to be available in late 2004. 

2. e-VLBI Development 

Haystack Observatory continues to develop the e-VLBI technique with a broad spectrum of 

0 VSI-E draft: After many months of fine tuning, the first VSI-E draft specification was distributed for discussion within the community. After a general consensus at the VLBI workshop in Dwingeloo that the RTP based framework would provide many advantages to the 

VLBI community, networking and astronomy researchers have been working to come up with 

a strawman solution that will be acceptable to both communities: meeting the requirements 

framework provides signaling, control, framing and statistics support and is an extension to I IVS 2003 Annual Report 241 

, efforts, including: 

1 

1 of the application while doing so in a manner that is efficient and network “friendly”. The 
Haystack TDC MIT Haystack Observatory 

the Internet standard RFC3550. It also provides flexibility in that it allows users to choose 

the transport protocol that most suits their networking environment (e.g. UDP, TCP or 

other variants). 

0 New connections to Wettzell and Kokee: Wettzell has recently installed a new E3 (34 Mbps) 

link to the University of Regensberg, which connects to the German Federal Network (DFN) 

and then the pan-European GEANT research network. Researchers at Wettzell, Hawaii and 

Haystack have been actively involved in testing this link and are looking forward to being able 

to utilize it to support Intensive experiments using e-VLBI. In Hawaii, a new OC3 link has 

been installed on Kauai between PMRF and Kokee Park. This has increased the bottleneck 

bandwidth from - 5 Mbps to - 80 Mbps. A series of experiments are planned that will use 

this bandwidth for the support of Intensive experiments. 

0 Regular data transfer from Kashima: Starting in October 2003, data from all of the sessions 

at the Kashima 34 m antenna have been recorded in K5 format and transferred to Westford 

via e-VLBI. The data were converted to Mark 5 format and then stored on Mark 5 disk 

pack before being sent for correlation on Mark 4 correlators. Thanks to the efforts of many 

people at CRL, USNO and Haystack the data were transferred successfully and fringes were 

detected for two of the experiments transferred so far. Sessions CRF22, CRF23 and T2023 

were all transferred using e-VLBI. The data were transferred from Kashima to Westford 

using BBFTP and special software to automate the transfer to a performance server at 

Haystack and then to a Mark 5 8-pack. The main purpose of this transfer was to verify the 

feasibility and automation software. The data rates for the sessions were relatively low, as 

the path they were traversing was bandwidth limited. It is expected that in the near future 

the path bandwidth will be significantly increased as part of a network upgrade. Session 

CRF22 involved the transfer of 442 GB of data at 11.02 Mbps using 4 parallel TCP streams. 

Session CRF23 involved the transfer of 489 GB of data at 11.8 Mbps using 4 parallel TCP 

streams. Session T2023 involved the transfer of 543 GB of data at 33.6 Mbps using 8 parallel 

TCP streams. 

0 Automated data transfers: As part of an ongoing effort, work is continuing on the development of toolkits for helping to automate the transfer of VLBI data across Wide Area 

Networks. This effort has resulted in tools that allow users to efficiently transfer large volumes of data between Mark 5 units and PCs across LANs as well as MANS. 

0 DRAGON: Researchers at Haystack have recently started a new project, the Dynamic Resource Allocation through GMPLS over Optical Networks (DRAGON) in collaboration with 

the University of Maryland Mid-Atlantic Crossroads (MAX), Univ. of S. California Information Sciences Institute, George Mason Univ., NASA/GSFC and USNO, and industry partner 

Movaz Networks. This project features e-VLBI as one of its premier applications and will 

provide advanced optical switching infrastructure for supporting e-VLBI experiments. 

0 Performance and testing: Haystack has been working in close collaboration with Internet2 

on the development of an automated performance tool, BGPerf. Ali Lotia and Charles Yun 

from Internet2 have developed a tool that automates the secure initiation and tear-down 

of “iperf” flows (“iperf” is a widely used network bandwidth measurement and estimation 

tool). Network performance tests with BGPerf are ongoing. BGPerf automates logging and 

timestamping of results, secure initiation of connections between clients and servers and 

242 IVS 2003 Annual Report 
MIT Haystack Observatory Haystack TDC 

resource usage limitation. It will soon include support for a database back end, multiple 

performance tools and parsing of output files to extract higher order performance results. 

Haystack has also developed a performance site for monitoring qualitative performance using 

existing tools such as MRTG, Smokeping, etc. 

0 Measurement and protocol testing: Network performance characterization and protocol testing between various eVLBI sites around the world continues. Tests within the United States, 

Japan, South America and Europe are ongoing. Recent results have demonstrated 360 Mbps 

disk-to-disk throughput using advanced transfer protocols and servers located in Tokyo, 

Japan and at Haystack. 

0 EGAE: Researchers at Haystack continue to work on the Experiment Guided Adaptive Endpoint (EGAE). This protocol will provide the interface between a VSI data acquisition system 

and the network. It will implement the RTP-based VSI-E protocol. Current experiments 

include looking at the suitability of various transport protocols (e.g. TCP, High speed TCP, 

SABUL, TSUNAMI, etc.) for use within this framework and how best to integrate these 

protocols into the EGAE. 

Figure 1. e-VLBI display at Internet2 meeting in Indianapolis, October 2002. 

0 Internet2 e-VLBI demonstration: An e-VLBI demonstration was given at the Internet2 Fall 

members meeting in October 2003 in Indianapolis. The demonstration was highly successful 

in raising awareness of VLBI and e-VLBI. In the demonstration area, a large display was 

constructed which described VLBI, e-VLBI, participants in VLBI and the application of 

VLBI to astronomical and geodetic applications. Two Mark 5 units were located in the 

IVS 2003 Annual Report 243 
Haystack TDC MIT Haystack Observatory 

demonstration area, both connected via optical fiber into a dedicated 1 Gbps stream that 

was connected into Abilene via a shared 10 Gbps trunk. Three laptop computers were 

used to display animations obtained from VLBI observations, video footage of the Westford 

telescope taken during a geodetic observing session and a real-time display of the application 

transport statistics. A demonstration was given of the transfer of VLBI data between the 

US and another International site using prototype RTP software. A demonstration was 

also given of the transfer of VLBI data between two Mark 5 systems located in the US. 

A maximum throughput of 207 Mbps was achieved. Demonstrators were also able to test 

memory to memory transfers between various sites and achieve a maximum TCP throughput 

of 460 Mbps using FAST TCP, 180 Mbps using TCP Reno and 400 Mbps using High Speed 

TCP. Sincere thanks go to the following institutions for their help and participation in this 

demonstration: 

- Arecibo Observatory, National Astronomy and Ionosphere Center of Cornel1 University, 

- Australia Telescope National Facility, Commonwealth Scientific and Industrial Research 

- Communications Research Laboratory, Kashima, Japan 

- Goddard Geophysical and Astronomical Observatory, Goddard Space Flight Center, 

- Joint Institute for VLBI in Europe, The Netherlands 

- MIT Haystack Observatory, Westford, MA 

- Smithsonian Astrophysical Observatory (Submillimeter Array), Mauna Kea, HI 

Puerto Rico 

Organisat ion, Sydney, Australia 

NASA, Greenbelt, MD 

244 IVS 2003 Annual Report 
Institute of Applied Astronomy Russian Academy of Sciences IAA Technology Development Center 

Institute of Applied Astronomy Technology Development Center 

Alexander Ipatov, Nikolay Koltsov, Andrey Mikhailov, Sergey Smolentsev 

Abstract 

The domain of IAA TDC includes the development of sotbare and hardware for Russian VLBI 

network QUASAR. This report describes IAA activities in this direction. 

1. General 

Technology Development Center is responsible for all parts of the Russian VLBI network and 

consists of separate laboratories developing hardware and software for this project. Now the 

32 m radio telescope in Svetloe is participating in international VLBI network observations and 

in domestic radioastronomical and VLBI observations. Radio telescope in Zelenchukskaya is participating in domestic radioastronomical and VLBI observations. At the Badary radio telescope 

the construction work is finished, the installation of the hardware and putting the telescope into 

operation will be done. 

2. Technical/Scient%c 

2.1. Timekeeping and Frequency 

The creation of the new phase calibrator “antenna unit” was finished in 2003. This devise has 

two pulses out for S and X bands receivers. Steprecovery diode is used for producing short pulses. 

Pulse performance: Duration = 50 ps, Amplitude = 1.2 V. 

Demultiplexer is similar to the original version documented in Mark I11 manual, but special 

Electronic module of the phase calibrator is installed into 54°C thermostat. The complex 

HYBFUD was used here. 

testing of the phase calibrator will be fulfilled in 2004. 

2.2. VLBI Data Acquisition System 

In 2003 the IAA Technology Development Center finished construction of the data acquisition 

system (DAS) for the S2-RT recording terminal. 

This DAS includes main module and up to 3 added modules. Each of modules contains distributor for 2 input IF signals (100-1OOO MHZ), 2 base band converters (BBCs), control unit and 

power-supply unit. So DAS may include from 2 up to 8 BBC’s, each of them contains video channels for upper and lower side bands and output 2-bit samplers. The digital signals levels meter 

controls levels of input IF signals and video signals. There are filters for selection of the harmonic 

phase calibration signals. DAS contains the 32 MHz clock and 1 PPS synchronizer for S2-RT. 

Computer with RS-232 interface controls DAS. 

Parameters of this DAS are showed in table 1. 

First module of new DAS produced in 2002 was tested in the Svetloe and Zelenchukskaya 

I observatories. In 2003 DAS of 4 modules (8 BBCs) for the SZ-RT recording terminal was produced 

IVS 2003 Annual Report 245 

I 
IAA Technology Development Center Institute of Applied Astronomy Russian Academy of Sciences 

Number of modules 

Number of base band converters 

Connection of base band converters to IF’ inputs 

Sidebands 

Image reiection 

Table 1. Parameters of the new DAS 

from 1 up to 4 

from 2 up to 8 

electronic switch 

upper and lower 

more then 26 dB 

Intermediate frequency range I 100-1000 MHz 

Number of IF inDuts 12 

vu 

Bandwidths 

IF attenuator’s range on distributor inputs 

IF attenuator’s range on base band converter’s input 

Number of digitizer bits 

0.25; 2; 8 and 16 MHz 

2 

(3-18 dB 

0-15 dB 

Attenuation step 

Phase noise of local oscillator 

Error of signal level measure 

1 dB 

0.1% 

less then 1.2 degree rms 

Clock Erequency for signal’s record 

Number of two-bits output streams 

Max Total Output Data Rate 

Module Dimension 

(Fig. 1). Now it is being tuned and tested by IAA TDC. We are planning to install new DAS at 

the Badary observatory in summer or in autumn 2004. 

v 

32 MHz 

up to 16 

1 Gbit/s 

300 x 445 x 465 mm 

2.3. The Software 

The investigations were made to improve the pointing accuracy of the antenna in Svetloe. The 

periodic nonlinearity errors of antenna position encoders were found previously during antenna 

calibration procedures. The amplitude of these errors is about 20-25 arcseconds, i.e. approximately 

10% of half power beam width on X-band. It may affect the results of observations on X-band 

and certainly prevents the quality observations on the shorter antenna wavelength 1.35 cm. After 

testing of encoders we came to conclusion that this problem is the result of a deficiency in the 

encoder’s design and elimination of nonlinearity is impossible. 

The special method of measurement of such errors was developed to solve the problem. The 

method doesn’t use any other equipment except the encoder itself and the antenna control system. 

The nonlinearity errors of encoders were measured in full range of antenna position angles. These 

results are used in antenna control software for correction of the errors. 

The software was updated for this purpose. The testing of antenna pointing with the correction 

of nonlinearity errors indicates that the accuracy became significantly better and is within few 

arcseconds. 

The important result of the pointing accuracy improvement is better antenna performance on 

the 1.35 cm band. First session of automatic pointing measurement was successfully carried out 

in this band using Field System software. 

246 IVS 2003 Annual Report 
Institute of Applied Astronomy Russian Academy of Sciences IAA Technolog Development Center 

1, 2, 3, 4 - DAS modules; 5 - control PC; 6 - oscilloscope for phase calibration signal 

monitorng; 7, 8, 9 - SZRT modules. 

Figure 1. 8-channel DAS with SZRT recording terminal 

IVS 2003 Annual Report 247 
IAA Technology Development Center Institute of Applied Astronomy Russian Academy of Sciences 

Stotsky 

Prof. Nikolay 

3. Technical Staff 

Researcher Radio holography 

Chief the Laboratory VLBI and +7-812-235-3316 nec@ipa.rssi.ru 

For all the IAA address (8, Zhdanovskaya st., St. Petersburg, 197110, Institute of Applied 

Astronomy (IAA) RAS, Russia, Director Andrey Finkelstein, FAX +7-812-230-7413) is valid. 

Koltsov 

Dr. Sergey 

Table 2. Technical Staff 

Signals Conversion radiometric 

Registration registration system 

Vice Director Time keeping +7-812-275-4415 smolen@ipa.rssi.ru 

Prof. Alexander I Main Scientific I Radio Physics I +7-812-235-3216 I stotskii@ipa.rssi.ru 

Smolent sev I Frequency standard I 

Salnikov 

Dr. Edward 

Korkin 

Dr. Irina 

Ipatova 

Dr. Vyacheslav 

Mardyshkin 

Mr. Andrey 

Mikhailov 

Dr. Dmitry 

Ivanov 

Dr. Leonid 

Fedotov 

Communication and Communication 

Computer Systems Computers 

Main Scientific Dish metal f7-812-230-7415 korkin@ipa.rssi.ru 

Researcher constructions 

Senior Scientific Receivers f7-812-230-6496 ipatova@ipa.rssi.ru 

Researcher Antenna 

performance 

Chief the Receivers Receivers +7-812-230-6496 vvm@iaa.nw.ru 

Laboratory Refrigerators 

Antenna 

performance 

Scientific FS software + 7-8 12-230-6496 agm@ipa.nw .ru 

Researcher Radio telescope 

Chief the Laboratory Time keeping f7-812-230-7416 labtf@ipa.rssi.ru 

Time and Frequency Frequency standart 

Senior Scientific BBC channels +7-812-235-3316 fedotov@ipa.rssi.ru 

Researcher 

control system 

4. Outlook 

In the new IVS year we are planning: 

0 to include the VLBI site Svetloe into routine geodetic VLBI observations using Mark 5 

facilities, 

0 to include the VLBI site Zelenchukskaya into routine geodetic VLBI observations using 

VLBA4 - Mark 5 facilities. 

248 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO), TDC 

The IVS Technology Development Center at the Onsala Space 

Observatory 

Gunnar Elgered 

Abstract 

The main activity during the yeas 2003 has been to assess the stability of the Water Vapor Radiometers 

(WVRs) usually operating at the Onsala Space Observatory. The method of calculating the Allan 

variance has been applied to data acquired before and after an upgrade of the Astrid WVR. We find 

the exercise meaningful and plan for repeated measurements optimized for monitoring of the WVR 

performance in terms of noise characteristics. 

1. Introduction 

In our Technology Development Center Report for the year 2002 we presented a s-y 

describing a new control and data acquisition system for the Astrid WVR El]. We started to operate 

the upgraded instrument in early 2003. After a few weeks of tuning of critical timing parameters 

and correcting software the instrument was acquiring data continuously with a reasonable degree 

of reliability from March 2003. 

Ideally the instrument characterization shall be carried out with the antenna beam pointing 

at a stable object in terms of emission comparable to typical sky brightness temperatures. Since 

such data are not available and especially not from the past, we decided to investigate if WVR 

observations made during stable atmospheric conditions could be used. 

This work has been carried out by Alejandro Alvarado and Park Pakniat within the frame 

of a Master Thesis project [2]. They have studied many WVR data sets obtained during different 

atmospheric conditions using different data acquisition schedules. I will here just highlight some 

interesting results. 

2. Preliminary Results 

The normal data acquisition sequence used by the WVRs at Onsala is to scan the whole sky 

through continuous azimuth and elevation scans. This type of data are not ideal to use in order 

to assess instrument stability over short time scales, simply because the atmospheric variabilitycomparing observations in Merent directions-% too large. Since it is the instrument stability that 

we want to study it is important to minimize the influence of the atmospheric signal. Therefore, 

we decided to focus on data taken in the zenith direction during clear days. 

An example from one of the most stable time series acquired in 2003, and the corresponding 

Allan variances, are shown in Figure 1 for the 21.0 GHz channel. The results for the 31.4 GHz 

channel are presented in Figure 2. The concept of Allan variance was developed for the characterization of frequency standards [3] but has ais0 been used to evaluate radiometer stability 

In general the minimum Allan variance has been reduced when comparing the data acquired 

in 2003 compared to those from the year 2000. The optimum integration times have also been 

reduced. The sky brightness temperatures observed in the year 2000 data are however significantly 

higher, especially at 21.0 GHz. It is likely that also atmospheric variability is contributing to the 

[41- 

IVS 2003 Annual Report 249 
Onsala Space Observatory (OSO), TDC Onsala Space Observatory (OSO) 

- 

I I 

observations in 031023a,21 GHz 

16 !’ I 1 I I I 

$ Y 10.’ o6 

------_-______ x l< -----_ -----__ 

-----__ 

11.5 1 

-1 

11 

[Kl 

10.5 

I‘ 

Figure 1. Time series of zenith measurements of the sky brightness temperature at 21.0 GHz (top plot). 

The Allan variance curve (bottom plot) is calculated from the first few hours (middle plot) showing a rather 

stable sky brightness temperature (from [2]). 

Allan variance for the short time scales and the comparison between the two years is of course 

also then affected by the different atmospheres. In any case, the results obtained indicate that the 

new data acquisition system of the Astrid WVR is working well. In addition to the stable time 

series presented here we have also note that a certain type of spurious data (outliers), seen in the 

31.4 GHz time series from year 2000, do not appear in the 2003 data. 

3. Future 

We are investigating if some special type of measurements, perhaps only of the internal reference loads, should be scheduled regularly in the future for the monitoring of the quality of the 

instrument. In fact it may even be worthwhile to make a similar type of analysis of our X/S-band 

receiver output during selected time periods between our geodetic VLBI experiments. 

250 IVS 2003 Annual Report 
Onsala Space Observatory (OSO) Onsala Space Observatory (OSO), TDC 

observations m 031023a. 31 GHz 

20 I I I I I I 

I 

- P 

I 

I 

I 

I I I I I I 

0 0.5 1 1 .s 2 2.5 3 3.5 51 

4 x 10 

A sekctedintervalin031023aats1GH2 

12 

ilQ 

11 

00:moz 03:35:41 

lo3.’ 

10‘ 

- 

ld3,5 

103,9 

too 10’ 

integration time [sec] 

Figure 2. Time series of zenith measurements of the sky brightness temperature at 31.4 GHz (top plot). 

The Allan variance curve (bottom plot) is calculated from the fist few hours (middle plot) showing a rather 

stable sky brightness temperature (from [2]). 

References 

[l] Elgered, G., and B. Stoew, IVS Technical Development Center Onsala Space Observatory, in Internutiond VLBI 

Service for Geodesy and Astrometry 2002 Annual Report, NASA/TP-2003-211619, eds. N. R. Vandenberg and 

K. D. Baver, pp. 311-313, 2003. 

[2] Alvarado, A., and P. Pakniat: Assessment of Water Vapour Radiometer Stability at 21 and 31 GHz, Masters 

Thesis, Department for Radio and Space Science, Chalmers University of Technology, in press, 2004. 

[3] Allan, D.W.: Statistics of Atomic Frequency Standards, Proc. IEEE, 5#(2), 221-230, 1966. 

[4] Rau, G., RSchieder, and B.Vohwinke1 Characterization and Measurement of Radiometer Stability, Pmc. 14th 

European Microwave Conf., pp. 248-253, Sept. 10-13, Liege, Belgium, 1984. 

IVS 2003 Annual Report 251 

i 

Terms OfReference 

IVS Terms of Reference 

1. Summary 

1.1. Charter 

The International VLBI Service for Geodesy and Astrometry (IVS) is an international collaboration of organizations which operate or support Very Long Baseline Interferometry (VLBI) 

components. IVS provides a service which supports geodetic and astrometric work on reference 

systems, Earth science research, and operational activities. 

IVS is an official Service of the International Association of Geodesy (IAG). 

1.2. Objectives 

IVS fulfills its charter through the following objectives. The primary objective of IVS is to 

foster VLBI programs as a joint service. This is accomplished through close coordination to 

provide high-quality VLBI data and products. 

The second objective of IVS is to promote research and development activities in all aspects 

of the geodetic and astrometric VLBI technique. This objective also supports the integration of 

new components into IVS. The further education and training of VLBI participants is supported 

through workshops, reports, electronic network connections, and other means. 

The third objective of IVS is to interact with the community of users of VLBI products and to 

integrate VLBI into a global Earth observing system. WS interacts closely with the International 

Earth Rotation Service (IERS) which is tasked by the IAU and IUGG with maintaining the 

international celestial and terrestrial reference frames and with monitoring Earth rotation. 

To meet these objectives, IVS coordinates VLBI observing programs, sets performance standards for VLBI stations, establishes conventions for VLBI data formats and data products, issues 

recommendations for VLBI data analysis software, sets standards for VLBI analysis documentation, and institutes appropriate VLBI product delivery methods to ensure suitable product quality 

and timeliness. IVS closely coordinates its activities with the astronomical community because of 

the dud use of many VLBI facilities and technologies for both astronomy and astrometry/geodesy. 

IVS accepts observing proposals for research and operational programs that conform to the 

IVS objectives. 

1.3. Data Products 

VLBI data products contribute uniquely to these important determinations: 

0 definition and maintenance of the celestial reference frame 

0 monitoring universal time (UT1) and length of day (LOD) 

0 monitoring the coordinates of the celestial pole (nutation and precession) 

These results are the foundation of many scientific and practical applications requiring the use 

of an accurate inertial reference frame, such as high-precision navigation and positioning. IVS 

provides, through the collaborative efforts of its components, a variety of significant VLBI data 

products with differing applications, timeliness, detail, and temporal resolution, such as: 

~ 

IVS 2003 Annual Report 255 I 

I 
Terms of Reference 

all components of Earth orientation parameters at regular intervals 

terrestrial reference frame 

VLBI data in appropriate formats 

VLBI results in appropriate formats 

local site ties to reference points 

high-accuracy station timing data 

surface meteorology, tropospheric and ionospheric measurements 

All VLBI data products are archived in IVS Data Centers and are publicly available. 

1.4. Research 

The VLBI data products are used for research in many related areas of geodesy, geophysics, 

UT1 and polar motion excitation (over periods of hours to decades) 

solid Earth interior research (mantle rheology, anelasticity, libration, core modes, nutacharacterization of celestial reference frame sources and improvements to the frame 

tidal variations (solid Earth, oceanic, and atmospheric) 

improvements in the terrestrial reference frame, especially in the vertical (scale) component 

climate studies 

and astrometry, such as: 

tion/precession) 

To support these activities, there are ongoing research efforts whose purpose is to improve and 

extend the VLBI technique in such areas as: 

improvements in data acquisition and correlation 

refined data analysis techniques 

spacecraft tracking (Earth-orbiting and interplanetary) 

combination of VLBI data and results with other techniques 

2. Permanent Components 

IVS acquires VLBI data, correlates the data, analyzes the data to produce geodetic, astrometric, 

and other results, and archives and publicizes data products. IVS accomplishes its goals through 

the types of permanent components described in this section. IVS will accept proposals at any 

time for a permanent component. Such proposals will be reviewed by the Directing Board. The 

seven types of IVS permanent components are: 

Network Stations 

Operation Centers 

Correlators 

256 IVS 2003 Annual Report 
Terms of Reference 

Analysis Centers 

Data Centers 

Technology Development Centers 

0 Coordinating Center 

IVS acquires VLBI data, correlates the data, analyzes the data to produce geodetic and astrometric results, and archives and publicizes data products. IVS accomplishes its goals through the 

operational components described below. 

2.1. Network Stations 

The IVS observing network consists of high performance VLBI stations. 

0 Stations can be dedicated to geodesy or have multiple uses (including astronomical obsemStations comply with performance standards for data quality and operational reliability set 

VLBI data acquisition sessions are conducted by groups of Network Stations that are distions or satellite tracking applications). 

up by the Directing Board. 

tributed either globally or over a geographical region. 

2.2. Operation Centers 

ation Center activities include: 

The IVS Operation Centers coordinate the routine operations of one or more networks. Oper0 planning network observing programs, 

establishing operating plans and procedures for the stations in the network, 

supporting the network stations in improving their performance, 

0 making correlator time available at an IVS Correlator, 

0 generating the detailed observing schedules for use in data acquisition sessions by IVS Netposting the observing schedule to an IVS Data Center for distribution and to the CoordinatIVS Operation Centers follow guidelines from the Coordinating Center for timeliness and schedule 

file formats. Operation Centers cooperate with the Coordinating Center in order to define: 

work Stations, 

ing Center for archiving. 

the annual master observing schedule, 

the use of antenna time, 

tape availability and shipping, 

the use of other community resources. 

IVS 2003 Annual Report 257 
Terms of Reference 

2.3. Correlators 

The IVS Correlators process raw VLBI data and station log files following a data acquisition 

0 provide immediate feedback to the Network Stations about problems that are apparent in 

0 jointly maintain the geodetic/astrometric community’s tape pool, 

0 make processed data available to the Analysis Centers, 

0 regularly compare processing techniques, models, and outputs to ensure that data from 

session. Their other tasks are to: 

the data, 

different Correlators are identical. 

2.4. Analysis Centers 

The IVS coordinates VLBI data analysis to provide high-quality products for its users. The 

analyses are performed by Analysis Centers and by Associate Analysis Centers. 

Analysis Centers are committed to produce series of Earth Orientation Parameters (EOP) or 

series of individual EOP components, without interruption and at a specified time lag to meet IVS 

requirements. In addition, Analysis Centers produce station coordinates and source positions in 

regular intervals. 

The Analysis Centers place their final results in IVS Data Centers for dissemination to researchers and other users. They adhere to IVS recommendations for the creation of high-quality 

products and their timely archiving and distribution. Any deviations that an Analysis Center 

makes from IVS recommendations are properly documented. Analysis Centers provide timely 

feedback about station performance. In addition to these regular services, Analysis Centers may 

also perform any task of an Associate Analysis Center. 

Associate Analysis Centers are committed to regularly submit specialized products using complete series or subsets of VLBI observing sessions. The analysis is performed for specific purposes 

as recognized by the Directing Board such as exploitation of VLBI data for new types of results, 

investigations of regional phenomena, reference frame maintenance, or special determinations of 

Earth orientation parameters. The Associate Analysis Centers place their final results in IVS Data 

Centers for dissemination to researchers and other users. They adhere to IVS recommendations for 

the creation of high-quality products and their timely archiving and distribution. Any deviations 

that an Associate Analysis Center makes from IVS recommendations are properly documented. 

2.5. Data Centers 

The IVS Data Centers are repositories for VLBI observing schedules, station log files, and data 

products. Data Centers may mirror other Data Centers to make the distribution and maintenance 

of data more efficient and reliable. 

0 Data Centers are the primary means of distributing VLBI products to users. 

0 Data Centers work closely with the Coordinating Center and with the Analysis Centers to 

ensure that all the information and data required by IVS components are quickly and reliably 

available. 

Data Centers provide the following functions: 

258 IVS 2003 Annual Report 
Terms of Reference 

0 receive and archive schedule files from Operation Centers, 

0 receive and archive log files and ancillary data files from the Network Stations, 

0 receive and archive data products from the Analysis Centers, 

0 provide access and public availability to IVS data products for all users. 

2.6. Technology Development Centers 

The IVS Technology Development Centers contribute to the development of new VLBI technology. They may be engaged-in hardware and/or software technology development, or evolve new 

approaches that will improve the VLBI technique and enhance compatibility with different data 

acquisition terminals. They will: 

0 design new hardware, 

0 investigate new equipment, 

0 develop new software for operations, processing or analysis, 

0 generate new information systems, 

0 develop, test, and document prototypes of new equipment or software, 

0 assist with deployment, installation, and training for any new approved technology. 

0 After dissemination of the new hardware or software, the centers may continue to provide 

maintenance and updating functions. 

2.7. Coordinating Center 

The IVS Coordinating Center is responsible for coordination of both the day-teday and the 

long-term activities of IVS, consistent with the directives and policies established by the Directing 

Board. Specifically, the Coordinating Center monitors, coordinates, and supports the activities 

of the Network Stations, Operation Centers, Correlators, Data Centers, Analysis Centers, and 

Technology Development Centers. The Coordinating Center works closely with the Technology 

Coordinator, the Network Coordinator, and the Analysis Coordinator to coordinate all IVS activities. 

The primary functions of the Coordinating Center are to: 

0 coordinate observing programs approved by the Directing Board, 

0 maintain the master schedule of observing sessions, coordinating the schedule with astro0 foster communications among all components of the IVS, 

0 define the best use of community resources, 

0 develop standards for IVS components, 

0 provide training in VLBI techniques, 

0 organize workshops and meetings, including an annual IVS technical meeting, 

0 produce and publish reports of activities of IVS components, 

nomical observing programs and with IVS networks, 

IVS 2003 Annual Report 259 
Terms of Reference 

a maintain the IVS information system and archive all documents, standards, specifications, 

a provide liaison with the IERS, IAG, IAU, and other organizations, 

a provide the Secretariat of the Directing Board. 

manuals, reports, and publications, 

3. Coordinators 

Specific IVS activities for technology, network data quality, and data products are accomplished 

through the functions performed by three coordinators: a Network Coordinator, an Analysis Coordinator, and a Technology Coordinator. 

3.1. Network Coordinator 

The IVS Network Coordinator is selected by the Directing Board from responses to an open 

solicitation to all IVS components. The Network Coordinator represents the IVS Networks on the 

Directing Board and works closely with the Coordinating Center. The Network Coordinator is 

responsible for stimulating the maintenance of a high quality level in the station operation and 

data delivery. The Network Coordinator performs the following functions: 

a monitors adherence to standards in the network operation, 

a participates in the quality control of the data acquisition performance of the network stations, 

a tracks data quality and data flow problems and suggests actions to improve the level of 

The Network Coordinator works closely with the geodetic and astronomical communities who 

are using the same network stations for observations. The Coordinator takes a leading role in 

ensuring the visibility and representation of the Networks. 

performance, 

3.2. Analysis Coordinator 

The IVS Analysis Coordinator is selected by the Directing Board from responses to an open 

solicitation to the IVS Analysis Centers. The Analysis Coordinator is responsible for coordinating 

the analysis activities of IVS and for stimulating VLBI product development and delivery. The 

Analysis Coordinator performs the following functions: 

fosters comparisons of results from different VLBI analysis software packages and different 

analysis strategies, 

encourages analysis software documentation, 

participates in comparisons of results fiom different space geodetic techniques, 

monitors Analysis Centers’ products for high quality results and for adherence to IVS standards and IERS Conventions, 

ensures that analysis products from all Analysis Centers are archived and available for the 

scientific community, and 

forms the official products of IVS, as decided by the IVS Directing Board, using a suitable 

combination of the analysis results submitted by the Analysis Centers. 

260 IVS 2003 Annual Report 

~~ 
Terms of Reference 

The Analysis Coordinator works closely with the geodetic and astronomical communities who 

are using some of the same analysis methods and software. The Analysis Coordinator plays a 

leadership role in the development of methods for distribution of VLBI products so that the 

products reach the widest possible base of users in a timely manner. The coordinator promotes the 

use of VLBI products to the broader scientific community and interacts with the IVS Coordinating 

Center and with the IERS. 

3.3. Technology Coordinator 

The IVS Technology Coordmator is selected by the Directing Board from responses to an 

open solicitation to the IVS Technology Development Centers. The Technology Coordinator is 

responsible for coordinating the new technology activities of IVS and for stimulating advancement 

of the VLBI technique. The Technology Coordinator performs the following functions: 

0 maintains cognizance of all current VLBI technologies and ongoing development 

0 coordinates development of new technology among various IVS components 

0 helps promulgate new technologies to the geodetic/astrometric community 

0 strives to ensure the highest degree of global compatibility of VLBI data acquisition systems 

The Technology Coordinator works closely with the astronomical community because of the 

many parallels between the technology development required for both groups. 

4. Directing Board 

4.1. Roles and Responsibilities 

The Directing Board determines policies, adopts standards, and approves the scientific and 

operational goals for IVS. The Directing Board exercises general oversight of the activities of IVS 

including modifications to the organization that are deemed appropriate and necessary to maintain 

efficiency and reliabilityA specific function of the Board is to set scientific goals for the IVS observing program. The 

Board will establish procedures for external research programs and will review any proposals thus 

received. 

The Board may determine appropriate actions to ensure the quality of the IVS products and 

that the IVS components maintain the adopted standards. 

4.2. Membership 

the Directing Board, and members elected by the IVS components. The members are: 

The Directing Board consists of appointed members who serve ex officio, members elected by 

Appointed members ex officio: 

0 IAG representative 

0 IAU representative 

0 IERS representative 

0 Coordinating Center Director 

IVS 2003 Annual Mort 261 
Terms of Reference 

Through a reciprocity agreement between IVS and IERS the IVS serves as the VLBI Technique 

Center for IERS, and as such its designated representative(s) serve on the IERS Directing Board. 

In turn, the IERS Directing Board designates a representative to the IVS Directing Board. This 

arrangement is to assure full cooperation between the two services. 

Selected by Directing Board upon review of proposals from IVS Member Organizations: 

0 Technology, Network, and Analysis Coordinators (3 total) 

Elected by Directing Board upon recommendation from the Coordinating Center (see below): 

0 Members at large (3) 

Elected by IVS Components (see below): 

0 Correlators and Operation Centers representative (1) 

0 Analysis and Data Centers representative (1) 

0 Networks representatives (2) 

0 Technology Development Centers representative (1) 

Total number: 15 

The four appointed members are considered ex officio and are not subject to institutional 

restrict ions. 

The five members of the Directing Board who are elected by IVS Permanent Components must 

each be a member of a different IVS Member Organization. All elected members serve staggered 

four-year terms once renewable. 

At large members are intended to ensure representation on the Directing Board of each of the 

components of IVS and to balance representation from as many countries and institutions and IVS 

interests as possible. At large members serve 2-year terms once renewable. 

A Board member who departs before the end of his/her term is replaced by a person selected 

by the Directing Board. The new member will serve for the remainder of the original term. 

The three Coordinators are selected by the Directing Board on the basis of proposals from 

IVS Member Organizations. On a two-thirds vote the Directing Board may call for new proposals 

for any Coordinator when it determines that a new Coordinator is required. Coordinators are 

encouraged to give at least three months notice before resigning. 

4.3. Elections 

Election of Board members by the IVS components shall be conducted by a committee of three 

Directing Board members, the chair of which is appointed by the chair of the Directing Board. 

The committee solicits nominations for each representative from the relevant IVS components. For 

each position, the candidate who receives the largest number of votes from the Associate Members 

will be elected. In case of a tie the Directing Board will make the decision. 

4.4. Chair 

The chair is one of the Directing Board members and is elected by the Board for a term 

of four years with the possibility of reelection for one additional term. The chair is the official 

representative of IVS to external organizations. 

262 IVS 2003 Annual Report 
Terms of Reference 

4.5. Decisions 

Most decisions by the Board are made by consensus or by simple majority vote of the members 

present. In case of a tie, the chair shall vote but otherwise does not vote. If a twethirds quorum is 

not present, the vote shall be held later by electronic mail. A twethirds vote of all Board members 

is required to modify the Terms of Reference, to change the chair, or to change any of the members 

elected by the Directing Board before the normal term expires. 

4.6. Meetings 

The Board meets at least annually, or more frequently if meetings are called by the chair or at 

the request of at least three Board members. The Board will conduct periodic reviews of the IVS 

organization and its mandate, functions, and components. The reviews should be done every four 

years. 

5. Definitions 

5.1. Member Organizations 

Individuals associated with NS Member Organizations may become IVS Associate Members. 

I Organizations that support one or more IVS components are IVS Member Organizations. 

5.2. Affiliated Organizations 

IVS component, are IVS Afliliated Organizations. Affiliated Organizations express an interest in 

establishing and maintaining a strong working association with NS to mutual benefit. Individuals 

affiliated with IVS Affiliated Organizations may become IVS Correspondents. 

1 Organizations that cooperate with IVS on issues of common interest, but do not support an 

5.3. Associate Members 

Individuals associated with organizations that support an IVS component may become IVS 

Associate Members. Associate Members are generally invited to attend non-executive sessions of 

the Directing Board meetings with voice but without vote. Associate Members take part in the 

election of the incoming members of the Directing Board representing the IVS components. 

5.4. Corresponding Members 

IVS Corresponding Members are individuals on a mailing list maintained by the Coordinating 

Center. They do not actively participate in IVS but express interest in receiving NS publications, 

wish to participate in workshops or scientific meetings organized by IVS, or generally are interested 

in IVS activities. Ex officio corresponding members are the following: 

I 

1 

i 

0 IAG General Secretary 

0 President of IAG Section I1 - Advanced Space Technology 

0 President of IAG Section V - Geodynamics 

0 President of IAU Division I - Fundamental Astronomy 

IVS 2003 Annual Report 263 
Terms of Reference 

0 President of IAU Commission 19 - Rotation of the Earth 

0 President of IAU Commission 8 - Positional Astronomy 

0 President of IAU Commission 31 - Time 

0 President of IAU Commission 40 - Radio Astronomy 

0 President of URSI Commission J - Radio Astronomy 

Individuals ae accepted as IVS Corresponding Members upon request to the Coordinating Center. 

Last modified: 15 February, 2001 

264 IVS 2003 Annual Report 
Members 

Organization 

Geoscience Australia 

University of Tasmania 

Vienna University of Technology 

Centro de Radio Astronomia e Apliw$jes Espaciais 

SDace Geodvaamics Laboratom 

IVS Member Organizations 

Country 

Australia 

Australia 

Austria 

Brazil 

Canada 

(alphabetized by country) 

Geodetic Survey Division, Natural Resources Canada 

Dominion Radio Astrophysical Observatory 

Canada 

Canada 

Universidad de Concepcihn 

Universidad del Bio Bio 

Universidad Cathlica de la Santisima Concepcibn 

Instituto Geogriifico Militar 

Chinese Academy of Sciences 

I Canadian S~ace AE~CY I Canada I 

Chile 

Chile 

Chile 

Chile 

China 

Observatoire de Paris 

Observatoire de Bordeaux 

Deutsches Geodatisches Forschunminstitut 

France 

Fhlce 

Germany ~ ~~~ 

Bundesamt fiir Kartographie und Geodiisie 

Forschungseinrichtung Satellitengeodiisie, TU-Munich 

Geodetic Institute of the University of Bonn 

Istituto di Radioastronomia CNR 

Anemia Soaziale Italiana 

Germany 

Germany 

Germany 

Italy 

Italy 

Geographical Survey Institute 

Communications Research Laboratory 

National Astronomical Observatory of Japan 

Japan 

Japan 

Japan ~ ~~~~ ~~ 

National Institute of Polar Research 

Norwepjan Defence hearch Establishment Norway 

Japan 

IVS 2003 Annual Report 265 

Norwegian Mapping Authority 

Astronomical Institute of St.-Petersburg University 

Institute of Applied Astronomy 

Norway 

Russia 

Russia 

Hartebeesthoek Radio Astronomy Observatory 

Instituto Geogriifico Nacional 

Chalmers University of Technology 

Main Astronomical Observatory, National Academy of Sciences, Kiev 

Laboratory of Radioastronomy of Crimean Astrophysical Observatory 

NASA Goddard Space Flight Center 

U. S. Naval Observatory 

Jet Propulsion Laboratory 

South Africa 

Spain 

Sweden 

Ukraine 

Ukraine 

USA 

USA 

USA 
IVS Affiliated Organizations 

Organization 

Australian National University 

University of New Brunswick 

Max-Planck-Institut fur Radioastronomie 

(listed alphabetically by country) 

Country 

Australia 

Canada 

Germany 

Satellite Geodetic Observatory 

Korea Astronomy Observatory 

Joint Institute for VLBI in Europe (JIVE) 

Westerbork Observatory 

Central (Pulkovo) Astronomical Observatory 

Hungary 

Korea 

Netherlands 

Netherlands 

Russia 1 National Radio Astronomy Observatory I USA I 

266 IVS 2003 Annual Report 
Name 

Aedo, R~berto 

I TIGO 

Institution Country Email 

Universidad del Bio Bio/Project Chile roberto.aedo@tigo.cl 

-1 

Amagai, Jun 

Andersen, Per 

Helge 

Arias, Felicitas 

Communications Research Japan amagai@crl.go.jp 

Laboratory 

Norwegian Defence Research Norway per-helge.andersen@ffi.no 

Establishment 

Bureau International des Poids F’rance farias@si.bipm.fr 

et Mesures 

Baudry, Alain 

Bauernfiend, 

Erhard 

Observatoire de Bordeaux F’rance baudr y 63observ.u-bordeaux.fr 

Fundamentalstation Wettzell Germany erhard.baUernfeind@bkg.bund.de 

Baver, Karen 

Beck, Norman 

Berman, Per 

Raytheon/GSFC USA kdb@leo.gsfc.nasa.gov 

Natural Resources Canada Canada beck@nrcan.gc.ca 

Onsala Space Observatory Sweden berman@oso.ch&ers.se 

B6rub6, Mario 

Bianco, 

Giuseppe 

Natural Resources Canada Canada mario@geod.nrcan.gc.ca 

Agenzia Spaziale Italiana Italy bianco@asi.it 

Bielmeier, 

Ewald 

Boboltz, David 

Fundamentalstation Wettzell Germany ewald.bielmeier@bkg.bund.de 

U. S. Naval Observatory USA dboboltz@usno.navy.mil 

I mc@maia.usno.navy.mil I USA I 1 Carter, Merri U. S. Naval Observatory s11e I 

Bohm, Johannes 

Bolotin, Sernei 

NS 2003 Annual &port 267 

Intitute of Geodesy and Austria johannes.boehm@tuwien.ac.at 

Geophysics 

Main Astronomical Observatory Ukraine bolotin@mao.kiev.ua 

Booth, by 

Bougeard, 

Mireille 

Onsala Space Observatory Sweden roy@oso.chalmers.se 

Observatoire de Paris fiance mireille.bougeard@obspm.fr 

Boyer, William 

Brazeau, 

Svlvain 

NASA Goddard Space Flight USA wboyer @gemini .gsfc.nasa.gov 

Center 

Natural Resources Canada Canada brazeau@geod.nrcan.gc.ca 

Buretta, Tom 

Buttaccio, Salvo 

Campbell, 

James 

Cannon, Wayne 

Cappallo, Roger 

Carlson, Brent 

MIT Haystack Ob&tory USA tburetta@haystack.mit .edu 

Istituto di Radioastronomia Italy s.buttaccio@iracnr .it 

CNR 

Geodetic Institute of the Germany campbell@sn_geod-l .geod.uniUniversity of Bonn bonn.de 

Space Geodynamics Laboratory Canada wayne@sgl.crestech.ca 

MIT Haystack Observatory USA rcappallo@haystack.mit .edu 

Dominion Radio Astrophysical Canada bcarlson@drao.nrc.ca 

Observatorv 
Associate Members 

Name Institution 

Caskey, Steve GCGO VLBI 

Chao, Benjamin NASA Goddard Space Flight 

Center 

Charlot, Patrick Observatoire de Bordeaux 

Chen, Songlin Shanghai Astronomical 

Colomer , Instituto GeogrAfico Nacional 

Francisco 

0 bservator y 

Country E-mail 

USA oper@blizzard.gcgo.nasa.gov 

USA chao@bowie.gsfc.nasa.gov 

France charlot @observ.u-bordeaux.fr 

China slchen@center.shao.ac.cn 

Spain colomer@oan.es 

Colucci, 

Giuseppe 

Combrinck, 

Ludwig 

Telespazio SPA Italy colucci@asi.it 

Hartebeesthoek Radio South ludwig@bootes.hartrao.ac.za 

Astronomv Observatory Africa 

Corey, Brian 

Corneliusson, 

Fredrik 

:a 

MIT Haystack Observatory USA bcorey@haystack.mit .edu 

Onsala Space Observatory Sweden fredrikc@oso.chalmers.se 

Cox, Clyde 

Daniels, Mike 

Honeywell TSI USA kokee@pele.kpgo.hawaii.edu 

Natural Resources Canada Canada mike.daniels@gdim.geod.nrcan.gc 

de-Vicente, 

Pablo 

Dewdney, Peter 

Instituto GeogrSco Nacional Spain vicente@oan.es 

Dominion Radio Astrophysical Canada ped@drao.nrc.ca 

Observatory 

Diegel, Irv 

Digre, Helge 

Doi, Koichiro 

Dong, Yousuo 

Honeywell TSI USA irv.diegel@honeywell-t,si.com 

Norwegian Mapping Authority Norway helge.digre@statkart .no 

National Institute of Polar Japan doi@nipr .ac.jp 

Research 

Urumqi Astronomical China uao@mail.wl.xj .cn 

Observatory 

Drewes, 

Hermann 

Dube, Maurice 

268 IVS 2003 Annual Report 

Deutsches Geodatisches Germany drewes@dgfi.badw-muenchen.de 

Forschungsinstitut 

RaytheonlGSFC USA mdube@pop900.gsfc.nasa.gov 

Eberhart, Kyle 

Elgered, Gunnar 

Engelhardt, 

Gerald 

Engen, Bjorn 

EssaYfi, Naiat 

GCGO VLBI USA oper@blizzard.gcgo.nasa.gov 

Onsala Space Observatory Sweden kge@oso.chalmers.se 

Bundesamt fur Kartographie Germany gerald.engelhardt@bkg.bund.de 

und Geodasie 

Norwegian Mapping Authority Norway b jorn.engen@statkart .no 

Observatoire de Paris France najat .essaifi@obspm.fr 

Fan, Qingyuan 

Farley, Stephen 

Shanghai Astronomical China qyfan@center.shao.ac.cn 

Observatory 

Natural Resources Canada Canada farley @Reod.nrcan.gc.ca 

Feil, Georg 

Feissel, Martine 

Fey, Alan 

Space Geodynamics Laboratory Canada georg@sgl .crestech .ca 

IGN/ENSG-LAREG France feissel@ensg.ign.fr 

U. S. Naval Observatorv USA afev@usno.navy.mil -, 

Finkelstein, 

Andrey 

Institute of Applied Astronomy Russia amf@quasar.ipa.nw.ru 
Associate Members 

Name 

Fischer , Dorothee 

Inst it u t ion Country Email 

Geodetic Institute of the Germany dorothee.fischer@uni-bonn.de 

University of Bonn 

Fkolov, Vladimir 

Gambis, Daniel 

Game, Ralph 

Institute of Applied Astronomy Russia fvn@isida.ipa.rssi.m 

Observatoire de Paris France daniel.gambis@obspm.fr 

U. S. Naval Observatow USA r gaume@usno.navy.mil 

Gipson, John 

Gomez, Frank 

GomezGonzalez, 

JeSUS 

Gontier, 

Anne- Marie 

NVI, Inc./GSFC USA jmg@leo.gsfc.nasa.gov 

Raytheon/GSFC USA fggegemini .gsfc.nasa.gov 

Institute Geogrfic~ Nacional Spain gomez@oan.es 

Observatoire de Paris France anne-marie.gontier@obspm.fr 

Godez, 

Ra-ymond 

Gordon. David 

NVI, Inc./GSFC USA rgonzale@gemini.gsfc.nasa.gov 

Ra-vtheonlGSFC USA dm@leo.e;sfcaasa.gov 

Govind, hesh 

Grachev, Valery 

Geoscience Australia I Australia rmesh.govind@ga.gov.au 

Institute of Applied Astronomy I Russia gratch@isida.ipa.rssi.ru 

Haw. Havo 1 BKG/Proiect TIGO I Chile havo.hase@bke;.bund.de 

Gradinarsky, 

Lubomir 

Gubanov, 

Vadim 

Onsala Space Observatory Sweden lbg@oso.chalmers.se 

Institute of Applied Astronomy Russia gubanov@quasar .ipa.nw .N 

Gueguen, 

ErWm 

Haas, Riidiger 

Istituto di Radioastronomia Italy e.gueguen@ira.cnr.it 

CNR 

Onsala Smce Observatorv Sweden haas@oso.chalmers.se 

IVS 2003 Annual Report 269 

Hall, David 

Hammargren, 

Roger 

U. S. Naval Observatory USA dhall@usno.navy.mil 

Onsala Space Observatory Sweden roger@oso.chalmers.se 

Hanssen, Rune 

Harms, Matt 

Norwegian Mapping Authority Norway rune.hanssen@statk .no 

Honeywell TSI USA kokee@pele.kpgo. hawaii.edu 

Helldner, kif 

Hmwich, Ed 

~ ~~ 

Onsala Space Observarry Sweden helldner@oso.chalmers.se 

"I, hc./GSFC USA weh@vega.gsfc.nasa.gov 

Hinteregger, 

Hans 

Hobiger, 

Thomas 

Holland, David 

Hong, Ximyu 

Huang, Xinyong 

MIT Haystack Observatory USA hhinteregger @haystack.mit .edu 

Intitute of Geodesy and Austria thobiger@mars.hg.tuwien.ac.at 

Geophysics 

Norwegian Mapping Authority Norway david.holland@statk.no 

Shanghai Astronomical China xhong@center .shm,.ac.cn 

Observatory 

Shanghai Astronomical China xhuang@center .shao.ac.cn 

0 bservator y 

Ichikawa, 

Ryuichi 

Communications Research Japan richi@crl.go.jp 

Laboratory 
Associate Members 

Name Inst it ut ion 

Ipatov, Institute of Applied Astronomy 

Alexander 

hatova, kina Institute of ADDlied Astronomy 

Country E-mail 

Russia ipatov@ipa.rssi.ru 

Russia ipatova@isida.ipa.rssi.ru ~~ 

Ishimoto, 

Masayoshi 

Jacobs. Chris 

~~~ 

Geographical Survey Institute Japan vlbi@gsi.go.jp 

Jet ProDulsion Laboratory USA Chris ..iacobs @j pl . nasa.gov 

Jara, Cristobal 

Jenson, George 

Johansson. Jan 

BKG/Project TIGO Chile cristobal.jara@tigo.cl 

Natural Resources Canada Canada gejensen@nrcan.gc.ca 

Onsala SDace Observatory Sweden imj @oso.chalmers.se ~~ 

Johansson, 

Karl- Wke 

Johansson. Lars 

~~~ 

Onsala Space Observatory Sweden kaj @oso.chalmers .se 

Onsala Space Observatory Sweden leb@oso.chalmers.se 

Johnson, Heidi 

Johnston, 

Kenneth 

MIT Haystack Observatory USA hjohnson@haystack.mit .edu 

U. S. Naval Observatory USA kjj@astro.usno.navy.mil 

Kaufmann, 

Pierre 

Kawai, Eiji 

Kawawa, 

Hiroshi 

270 IVS 2003 Annual Report 

Centro de Mi0 Astronomia e Brazil kaufmann@usp. br 

Aplica$es Espaciais 

Communications Research Japan kawa@crl.go.jp 

Laboratory 

Geographical Survey Institute Japan vlbi@gsi.go.jp 

Kaydanovsky, 

Michael 

Kennard, Ruth 

Institute of Applied Astronomy Russia kmn@isida.ipa.rssi.ru 

Rayt heon / G SFC USA rkennard@pop900 .gsfc . nasa . gov 

Kilger, Richard 

Kim, Kelly 

Kimura, 

Moritaka 

Kingham, Kerry 

Klatt, Calvin 

Fundamentalstation Wettzell Germany richard.kilger@bkg.bund.de 

Honeywell TSI USA kokee@pele. kpgo. hawaii .edu 

Communications Research Japan yosh@crl.go.jp 

Laboratory 

U. S. Naval Observatory USA kak@cygx3.usno.navy.mil 

Natural Resources Canada Canada klatt@geod.emr.ca 

Kodak, Charles 

Koltsov, Nikolay 

Kondo, Tetsuro 

Korkin, Edward 

Koyama, 

Yasuhiro 

Kozin, Wada 

Kozlova, Iraida 

Honeywell TSI USA Charles .kodak@honeywell-tsi .com 

Institute of Applied Astronomy Russia nec@isida.ipa.rssi.ru 

Communications Research Japan kondo@crl.go.jp 

Laboratory 

Institute of Applied Astronomy Russia korkin@isida.ipa.rssi.ru 

Communications Research Japan koyama@crl.go. jp 

Laboratory 

Geographical Survey Institute Japan vlbi@gsi.go.jp 

Institute of Amlied Astronomy Russia via@quasar .ipa.nw .Tu 

Krasinsky, 

George 

Kronschnabl, 

Gerhard 

Institute of Applied Astronomy Russia kra@quasar.ipa.nw.ru 

Bundesamt fur Kartographie Germany gerhard.kronschnabl@bkg.bund.de 

und Geodasie 
Associate Members 

Name Institution 

Kuboki, Communications Research 

Hiromitsu Laboratory 

Kudryashova, Astronomical Institute of 

Maria St .-Petersburg 

Kurihara, Geographical Survey Institute 

Shinobu 

Kutterer, DGFI 

Hansjoerg 

LaFrance, Natural Resources Canada 

Jacaues 

Country Email 

Japan yosh@crl.go.jp 

Russia kudryashova@mercury.astro.spbu. 

Japan vlbi@gsi.go.jp 

Germany kutterer@dgfi.badw.de 

Canada lafrance@geod.emr.ca 

Lanotte, 

Roberto 

Li, Jinling 

Li, Sing 

Telespazio SpA IdY lanotte@hp835.mt .asi.it 

Shanghai Astronomical China jll@center.shao.ac.cn 

Observatory 

Shanghai Astronomical China bing@center.shao.ac.cn 

Observatory 

Li, Suqin 

Liang, Shiguang 

Urumqi Astronomical China uao,@mail.wl.xj.cn 

Observatory 

Shanghai Astronomical China sgliang@center.shao.a,c.cn 

Observatory 

Liu, Xiang 

Lizin, Igor 

Long, Jim 

Lonsdale, Colin 

Lucena, Antonio 

Ma, Chop0 

IVS 2003 Annual Report 271 

Urumqi Astronomical China uao@mail.wl.xj.cn 

Observatory 

Institute of Applied Astronomy Russia lizin@isida.ipa.rssi.ru 

Honeywell TSI USA jim.long@honeywell-tsi.com 

MIT Haystack Observatory USA clonsdale@haystack.mit .edu 

Centro de Mo Astronomia e Brazil macilio@roen.inpe. br 

Aplicaqiies Espaciais 

NASA Goddard Space Flight USA chopma-l@nasa.gov 

Center 

Maccaferri, 

Giuseppe 

Machida, 

Morito 

MacMillan, Dan 

Malkin, Zinovy 

Manabe, Seiji 

Mantovani, 

hanco 

Mardyshkin, 

Vyvacheslav 

Istituto di Radioastronomia Italy g.maccaferri@ira.cnr.it 

CNR 

Geographical Survey Institute Japan vlbi@gsi .go. jp 

NVI, Inc./GSFC USA dsm@leo.gsfc.nasa.gov 

Institute of Applied Astronomy Russia malkin @quasar. ipanw .ru 

National Astronomical Japan manabe@miz.nao.ac.jp 

Observatory of Japan 

Istituto di Radioastronomia Italy f.manto&@ira.cnr.it 

CNR 

Institute of Applied Astronomy Russia wm@isida.ipa.rssi.ru 

Mathias, 

William 

Matsuzaka, 

Shineru 

Natural Resources Canada Canada wmathias@nrcan.gc.ca 

Geographical Survey Institute Japan shigeru@gsi.go.jp 
Associate Members 

Name Institution 

McCarthy, U. S. Naval Observatory 

Dennis 

McCulloch, University of Tasmania 

Peter 

Country E-mail 

USA dmc@maia.usno.navy.mil 

Tasmania peter.mcculloch@utas.edu.au 

Michailov, 

Andrey 

Mitchell, 

Donald 

Muskens, Arno 

Nakajima, 

Junichi 

Nanni, Mauro 

Institute of Applied Astronomy Russia agm@isida.ipa.rssi.ru 

Honeywell TSI USA kokee@pele.kpgo.hawaii.edu 

Geodetic Institute of the Germany mueskens@mpifr-bonn.mpg.de 

University of Bonn 

Communications Research Japan nakaji@crl.go.jp 

Laboratory 

Istituto di Radioastronomia Italy m.nanni@ira.cnr.it 

CNR 

Negusini, Monia 

Newby, Paul 

Nicolson, 

George 

Niell, Arthur 

Novikov , Alexander 

Istituto di Radioastronomia Italy m.negusini@ira.cnr.it 

CNR 

Space Geodynamics Laboratory Canada paul@sgl .crestech .ca 

Hartebeesthoek Radio South george@bootes.hartra.ac.za 

Astronomy Observatory Africa 

MIT Haystack Observatory USA miell@ hay st ack.mit .edu 

Space Geodynamics Laboratory Canada sasha@sgl.crestech.ca 

Nikitin, Pave1 

Nilsson, Bjorn 

Noll, Carey 

Nothnagel, Axel 

Ogaja, Clement 1 Geoscience Australia I Australia I Clement.Ogaja@ga.gov.au I 

Laboratory of Radioastronomy Ukraine nikitin@crao.crimea.ua 

of Crimean 

Onsala Space Observatory Sweden bin@oso.chalmers.se 

NASA Goddard Space Flight USA noll@cddisa.gsfc.nasa.gov 

Center 

Geodetic Institute of the Germany nothnagel@uni-bonn.de 

University of Bonn 

Orfei, Sandro Istituto di Radioastronomia a.orfei@ira.cnr.it 1 CNR 

Osaki, Hiro 

Outhwaite, Bill 

Petrachenko, 

William 

Petrov, Leonid 

Pettersson, Lars 

Hans-Peter 

Plotz, Christian 

_- -_ 

Communications Research Japan yosh@crl.go.jp 

Laboratory 

Natural Resources Canada Canada wouthwai@nrcan.gc.ca 

Natural Resources Canada Canada biIlp@cass.drao.nrc.ca 

NVI, Inc./GSFC USA pet@leo.gsfc.nasa.gov 

Onsala Space Observatory Sweden larsp@oso.chdmers.se 

Norwegian Mapping Authority Norway plag@statkart .no 

Fundamentalstation Wettzell Germany christian.ploetz@bkg.bund.de 

Poirier, Michael 

Popelar, Josef 

272 IVS 2003 Annual Report 

MIT Haystack Observatory USA mpoirier@ haystack.mit .edu 

Natural Resources Canada Canada popelar@geod.emr .ca 
~ 

Rahimov, Ismail 

Redmond, Jay 

~ ~~ 

Institute of Applied Astronomy 

Honeywell TSI 

Reid, Brett 

Rekkedal, Svein 

University of Tasmania 

Norwegian Mapping Authority 

Remedi, 

Gonzalo 

Rioja, Maria 

- ~~ ~ 

Universidad del Bio Bio/Project 

TIGO 

Centro Astron6mico de Yebes 

&so, 

Domenico 

Rottmann, 

Izabela 

Telespazio SpA 

Geodetic Institute of the 

University of BOM 

Schemeck, 

HansGeorg 

Schliiter, 

Wolfgang 

Schuh, Harald 

Onsala Space Observatory 

Bundesamt fiir Kartographie 

und GeodGie 

Intitute of Geodesy and 

Geophysics 

Sciaxretta, 

Cecilia 

Searle, Anthonv 

Telespazio SPA 

Geodetic Survev Division 

Sekido, Mamoru 

ShafTer, David 

Communications Research 

Laboratory 

Radiometrics Inc. 

Shao, Minghui 

Shibuya, Kazuo 

Shu, Fengchun 

Urumqi Astronomical 

Observatory 

National Institute of Polar 

Research 

Shanghai Astronomical 

0 bservator y 

ABsociate Members 

Name I Institution 

Astronomv Observatow 

Country Email 

China qzh@center.shao.ac.cn 

South jon@bootes.hartrao.ac.za 

Africa ~~ 

Russia 

USA 

iar@ipa.rssi.ru 

jay.redmond@honeywell-tsi-corn 

Brett .Reid@utas.edu.au 

svein.rekkedal@statkaxttatkast.no 

Tasmania 

Norway 

Chile gonzalo.remedi@tigo.cl 

~ 

Spain rioja@oan.es 

Italy domenicodelr osso@telespazio.it 

Germany owsianik@mpifr-bonn.mpg.de 

Rusinov. Yuriv I Institute of A~~lied Astronomv Russia 

Russia 

rusinov@quasar.ipa.nw.ru 

Salnikov, Institute of Applied Astronomy salnikov@isida.ipa.rssi.ru 

Alexander 

Italy p.sarti@ira.cnr.it 

Schatz, hdamentalstation Wettzell 

Raimund 

Germany raimund.schatz@bkg.bund.de 

Sweden hgs@oso.chahers.se 

Wolfgang.Schlueter @bkg.bund.de 

Austria harald.schuh@tuwien.ac.at 

USA bruce.schupler @honeywellt,si.com 

walter.schwarz@ bkg. bund-de 

und Geodikie 

Italy cecilia@asi.it 

Canada asearle@NRCan.nc.ca 

Japan sekido@crl .go. jp 

USA dbs@nemini.nsfc.nasa.nov 

China uao@mail.wl.xj.cn 

Japan shibuya@nipr.a.c.jp 

~____ 

China sfc@center.shao.ac.cn 

NS 2003 Annual Report 273 
Associate Members 

Name 

Skurikhina, 

Elena 

Smolent sev , Seraev 

Institution Country E-mail 

Institute of Applied Astronomy Russia sea@quasar.ipa.nw.ru 

Institute of Applied Astronomy Russia smolen@isida.ipa.rssi.ru 

Smythe, DG 

Sobarzo, Sergio 

Sousa, Don 

Sovers, Ojars 

Stanghellini , Carlo 

Steinforth, 

Christoph 

MIT Haystack Observatory USA dsmythe@haystack.mit .edu 

BKG/Project TIGO Chile sergio.sobarzo@tigo.cl 

MIT Haystack Observatory USA dsousa@haystack.mit .edu 

Remote Sensing Analysis Inc. USA o jars@rsasys .com 

Istituto di Radioastronomia Italy c.stanghellini@ira.cnr.it 

CNR 

Geodetic Institute of the Germany steinforth@uni-bonn.de 

University of Bonn 

Steppe, Alan 

Stoew, Borys 

Stotsky, 

Alexander 

Takeuchi, 

Hiroshi 

Jet Propulsion Laboratory USA as@logos.jpl.nasa.gov 

Onsala Space Observatory Sweden boris@oso.chalmers.se 

Institute of Applied Astronomy Russia stotskii@isida.ipa.rssi.ru 

Communications Research yosh@crl.go.jp 

Laboratory 

Surkis, Igor 

Takashima, 

Kazuhiro 

Institute of Applied Astronomy Russia surkis@quasar.ipa.nw.ru 

Geographical Survey Institute Japan takasima@gsi.go.jp 

Tamura, National Astronomical 

Yoshiaki Observatory of Japan 

Tangen, Leif Norwegian Mapping Authority 

Morten 

Japan tamura@miz .nao.ac. jp 

Norway leif.morten.tangen@statkart .no 

Torres, Miguel di Radioastronomia 

Tateyama, 

Claudio 

Tesmer, Volker 

m.torres@ira.cnr.it 

Centro de Mi0 Astronomia e Brazil tateyama@craam.mackenzie.br 

Aplicqhs Espaciais 

DGFI Germany tesmer@dgfi.badw.de 

Thomas, 

Cynthia 

Thorandt, 

Volkmar 

Thornton , Bruce 

Titov, Oleg 

Titus, Mike 

Tomasi, Pa010 

274 

NVI, Inc./GSFC USA cct@gemini.gsfc.nasa.gov 

Bundesamt fur Kartographie 

und Geodasie 

U. S. Naval Observatory USA blt@casa.usno.navy.mil 

Geoscience Australia Australia Oleg.Titov@ga.gov.au 

MIT Haystack Observatory USA mtitus@haystack.mit.edu 

Istituto di Radioastronomia Italy tomasi@ira.cnr.it 

CNR 

Germany volkmar . t horand t @ b kg . bund. de 

~~~~ - 

IVS 2003 Annual Report 

'Tkigilio, 

Corrado 

Tsuji, Hiromichi 

Istituto di Radioastronomia Italy c.trigilio@ira.cnr.it 

CNR 

Geographical Survey Institute Japan vlbi@gsi.go.jp 
Name I Institution Country 

Japan 

I 

Tsutsumi , 1 Geographical Survey Institute 

Email 

vlbi@gsi.go-jp 

Takashi 

Tuccari, Gin0 

Ullrich, Dieter 

Vandenberg, 

Nt3UC.Y 

Vennebusch, Geodetic Institute of the 

University of Bonn 

Istituto di Radioastronomia 

CNFt 

Bundesamt fiir Kartographie 

und Geodtisie 

"VI, Inc./GSFC 

__ 

vespe, Agenzia Spaziale Italiana 

nancesco 

Villiard, Raytheon/GSFC 

Cynthia 

Vityazev, Astronomical Institute of 

Veniamin St .-Petersburg 

Germany 

Volvach, Laboratory of Radioastronomy 

Vytnov, Institute of Applied Astronomy 

Alexander 

dieter.ullrich@bkg.bund.de 

Wang, Guangli Shanghai Astronomical I ObservatoIY 

USA 

Wang, Na Ununqi Astronomical 

Observatory 

nrv@gemini.gsfc.nasa.gov 

China wgl@center.shao.ac.cn 

Wei, Wenren 

Whitney, Alan 

Shanghai Astronomical 

Observatory 

MIT Haystack observatory 

Italy 

China 

USA 

g.tucca,ri@ira.cnr.it 

wwr@center.Shao.ac.cn 

awhitney@haystack.mit.edu 

Wildes, William 

Wo jdziak, 

Reiner 

Xue, Zhouhe 

NASA Goddard Space Flight 

Center 

Bundesamt fiir Kartographie 

und GeodGie 

Shanghai Astronomical 

Observatory 

t.venturi@ira.cnr .it 

USA 

Germany 

China 

Italy 

wtw@wildbill.gsfc.na.gov 

reiner .wo jdziak@bkg .bund .de 

zhxue@center .shao.ac.cn 

vespe@asi.it 

Yang, Zhigen 

Yatskiv, 

Yaroslav 

Ye, Shuhua 

Yoshino, Taizoh 

cav@gemini.gsfc.nasa.gov 

Russia vityazw@venvi.usr.pu.ru 

Shanghai Astronomical 

Observatory 

Main Astronomical Observatory 

Shanghai Astronomical 

Observatory 

Communications Research 

Laboratory 

volvach@crao.crimea.ua 

Russia vytnov@isida.ipa.rssi.ru 

Japan yosh@crl.go.jp 

um@mail.wl.xj.cn 

uao@mail.wl.xj.cn 

yangz@center .shm.ac.cn 

Ukraine yatskiv@mao .kiev .ua 

China I ysh@center.shao.ac.cn 

I 

IVS 2003 Annual Report 275 
Associate Members ~ 

Country E-mail - 

China uao@mail.wl .xj.cn 

Name 

Yusup, Aili 

Zeitlhofler, Fundamentalstation Wettzell 

Zen, Yong Urumqi Astronomical 

Observatory 

Institution 

Urumqi Astronomical 

Observatory 

1 Zernecke, ~ 1 Fundiment alstation ~ett ze11

Rudolf 

Zhang, Ali Urumqi Astronomical 

0 bservatory 

Zhang, Jin Urumqi Astronomical 

uao@mail.wl.xj .cn 

I 

China I uao@maiI.wl .xj. cn 

China uao@mail.wl .xj.cn 

China zrx@center.shao.ac.cn 

276 IVS 2003 Annual Report 
IVS Permanent Components 

IVS Permanent Components 

(listed by types, within types alphabetical by component name) 

Network Stations 

Component Name Sponsoring Organization country 

Algonquin Radio Observatory Geodetic Survey Division, Natural Canada 

Resources Canada 

Fortaleza, Radio Observathrio Espacial do Centro de Rridio Astronomia e Apliqiks Brazil 

Nordes (ROEN) E5paciais 

Gilmore Creek Geophysical Observatory National Earth Orientation Service USA 

Goddard Geophysical and Astronomical NASA Goddard Space Flight Center USA 

Observatory 

Hartebeesthoek Radio Astronomy Hartebeesthoek Radio Astronomy South Africa 

Observatory Observatory _____ ~~ ~ ~ 

Hobart, Mt. Pleasant Radio Astronomy 

Kashima 34m antenna Communications Research Laboratory Japan 

Kashima llm antenna Communications Research Laboratory Japan 

Hobart, Mt. Pleasant Radio Astronomy Australia 

Observatory Observatory 

Koganei llm antenna 

~ _____ ~ ~~ ~~ ~~ 

Communications Research Laboratory Japan 

Kokee Park Geophysical Observatory 

~ ~ ~~ 

National Earth Orientation Service USA 

Matera Agenzia Spaziale Italiana Italy 

Medicina (Italy) Istituto di Radioastronomia CNR Italy 

Mizusawa National Astronomical Observatory of Japan 

Japan 

Noto (Sicily) Istituto di Radioastronomia CNR Italy 

Ny &and Geodetic Observatory Norwegian Mapping Authority Norway 

ERS/VLBI Station O’Higgins Bundesamt fiir Kartographie und Geodiisie Germany 

Onsala Space Observatory Chalmers University of Technology Sweden 

seshan Shanghai Observatory, Chinese Academy China 

of sciences 

Simeiz Laboratory of Radioastronomy of Crimean Ukraine 

Svetloe Radio Astronomy Observatory Institute of Applied Astronomy Russia 

Astrophysical Observatory 

~~~~~~ ~ ~~~ ~ ~ 

JARE Syowa llm antenna National Institute of Polar Research Japan ~ 

llansportable Integrated Geodetic Bundesamt fiir Kartographie und Geodiisie Germany 

Observatory (TIGO) 

Tsukuba VLBI Station Geographical Survey Institute Japan 

IVS 2003 Annual Report 277 
IVS Permanent Components 

Nanshan VLBI Station of Urumqi Shanghai Observatory, Chinese Academy China 

Astronomical Observatory (UAO) of Sciences 

Westford Antenna, Haystack Observatory NASA Goddard Space Flight Center USA 

Fundamentalstation Wettzell Bundesamt fur Kartographie und Germany 

Geodasie and Forschungseinrichtung 

Satellitengeodbie de Technischen 

Universitat Munchen 

Observat6rio Astron6mico Nacional - Instituto GeogrAfico Nacional Spain 

Yebes 

Yellowknife Geophysical Observatory Geodetic Survey Division, Natural Canada 

Resources Canada 

Operat - ion Centers 

I Component Name Sponsoring Organization Country ~ I Geodetic Institute Bonn Geodatisches Institut der Universitat Bonn Germany I 

 ORE Operation Center NASA Goddard Space Flight Center USA I ~~ I NEOS Operation Center National Earth Orientation Service USA I 

Correlators 

Component Name Sponsoring Organization Country 

Astro/Geo Correlator at the Bundesamt fur Kartographie und Germany 

Max-Planck-Institute for Radio Astronomy Geodikie and Geodatisches Institut der 

Universitat Bonn 

1 Kashima VLBI Correlators Communications Research Laboratory Japan I 

1 MIT Haystack Observatory Correlator NASA Goddard Space Flight Center USA I 

I Institute of Applied Astronomy Correlator Institute of Applied Astronomy Russia I 

1 Tsukuba VLBI Center Geographical Survey Institute Japan I 

1 Washington Correlator National Earth Orientation Service USA I 

278 IVS 2003 Annual Report 
t 

7 ~~ ~ 

Crustal Dynamics Data Information NASA Goddard Space Flight Center USA 

System (CDDIS) 

GeoDAF Agenzia Spaziale Italiana Italy 

Italy cm Istituto di Radioastronomia CNR Italy 

IVS Permanent Components 

Data Centers 

Component Name Sponsoring Organization country 

BKG, Leipzig Bundesamt fiir Kartographie und Geodbie Germany 

Communications Research Laboratory Communications Research Laboratory Japan 

Observatoire de Paris France I 

Analvsis Centers 

Component Name Sponsoring Organization country 

Astronomical Institute of St.-Petersburg Astronomical Institute of St.-Petersburg Russia 

University University 

GA IVS Analvsis Center Geoscience Australia Australia 

Bordeaux Observatorv Observatoire de Bordeaux France 

Centro di Geodesia Spaziale (CGS) Agenzia Spaziale Italiana Italy 

Communications Research Laboratory Communications Research Laboratory Japan 

DGFI Deutsches Geodatisches Forschungsinstitut Germany 

Forsvarets forskningsinstitutt (FFI) Norwegian Defence Research Norway 

Establishment 

GlUB-BKG Analysis Center Geodatisches Institut der Universitiit 

Bonn and Bundesamt fiir Kartographie 

und Geodiisie 

Goddard Space Flight Center NASA Goddard Space Flight Center USA 

Haystack Observatory NASA Goddard Space Flight Center USA 

Institute of Applied Astronomy Analysis Institute of Applied Astronomy Russia 

Center 

Italy CNR Istituto di Radioastronomia CNR Italy 

Institute of Geodesy and Geophysics 

(IGG) 

Vienna University of Technology Austria 

~ ~~ ~~ ~~ 

Jet Propulsion Laboratory Jet Propulsion Laboratory USA ~ ~ ~~ 

Main Astronomical Observatory National Academy of Sciences, Kiev Ukraine 

NAO J National Astronomical Observatory of Japan 

Japan 

Observatoire de Paris Observatoire de Paris France 

Onsala Space Observatory Chalmers University of Technology Sweden 

IVS 2003 Annual Report 279 
IVS Permanent Components 

Shanghai Observatory Shanghai Observatory, Chinese Academy China 

U. S. Naval Observatory U. S. Naval Observatory USA 

USNO Analysis Center for Source U. S. Naval Observatory USA 

Structure 

of Sciences 

Technology Development Centers 

Component Name Sponsoring Organization Country 

Canadian VLBI Technology Development Space Geodynamics Laboratory, Geodetic Canada 

Center Survey Division, Dominion Radio 

Astrophysical Observatory, Canadian 

Space Agency 

Communications Research Laboratory Communications Research Laboratory Japan 

Forsvarets forskningsinstitutt (FFI) Norwegian Defence Research Norway 

Goddard Space Flight Center NASA Goddard Space Flight Center USA 

MIT Haystack Observatory National Earth Orientation Service USA 

Institute of Applied Astronomy Institute of Applied Astronomy Russia 

Technology Development Center 

Establishment 

Onsala %ace Observatorv Chalmers University of Technology Sweden 

280 IVS 2003 Annual Report 
Contributing Institutions 

Addresses of Institutions of Authors Contributing to this Report 

(listed alphabetically by country) 

Geoscience Australia 

PO Box 378 

Canberra ACT 

2601 

Australia 

http://ga.gov.au 

Hobart, Mt. Pleasant Radio Astronomy Observatory 

School of Mathematics and Physics 

University of Tasmania 

Hobart 7001 

Australia 

GPO BOX 252-37 

Institute of Geodesy and Geophysics/University of Technology, Vienna 

Gusshausstrasse 27-29 

1040 Vienna 

Austria 

http: / /www .hg.tuwien.ac.at 

Centro de RMio Astronomia e Aplic.aq&s &paciais, CRAAE (Mackenzie, INPE, USP, UNICAMP) 

CRAAE 

Instituto Presbiteriano Mackenzie 

Rua da Consolaqiio 896 

01302-907 Siio Paul0 

SP 

Brazil 

http: //www .craae.mackenzie. br 

FUio Observat6rio Espacial do Nordeste, ROEN 

Estrada do Fio 6ooo 

Bairro Tupuili 

61760-000 Euskbio 

CE 

Brazil 

http://www.roen.inpe.br 

Geodetic Survey Division, Geomatics Canada, Natural Resources Canada 

615 Booth St. 

Ottawa 

Ontario 

Canada K1A OE9 

http://www .geod.nrc.gc.ca 

IVS 2003 Annual Report 281 
Contributing Institutions 

York University and SGL/CRESTech 

4850 Keele St. 

Floor 1 North York 

Ontario 

Canada M3J 3K1 

http: / /www.sgl.crestech.ca 

Bundesamt fiir Kartographie und GeodLie - TIGO 

Casilla 4036 

Correo 3 

Concepci6n 

Chile 

http://www.tigo.cl 

Universidad de Concepcih - TIGO 

Concepci6n 

Chile 

http://www.tigo.cl 

Universidad del Bio Bb - TIGO 

Concepci6n 

Chile 

http://www.tigo.cl 

Shanghai Astronomical Observatory, Chinese Academy of Sciences 

80 Nandan Road 

Shanghai 200030 

People’s Republic of China 

http:/ /center .shao.ac.cn/ 

Observatoire de Bordeaux 

BP 89 

33270 Floirac 

France 

http://www.obs.u-bordeaux1 .fr 

Observatoire de Paris, SYRTE/UMR 8630 

61 avenue de I’Observatoire 

75014 Paris 

France 

http://www.obspm.fr 

Bundesamt fur Kartographie und GeodLie 

Karl-Rothe- StraDe 10-1 4 

04105 Leipzig 

Germany 

http://www.leipzig.ifag.de 

IVS 2003 Annual Report 282 
Contributing Institutions 

Bundesamt fiir Kartographie und Geodikie - Fundamentalstation Wettzell 

Sackenrieder Str. 25. 

D-93444 Kotzting 

Germany 

http://www.wettzell.ifag.de 

I DGFI, Deutsches Geodatisches Forschungsinstitut Marstallplatz 8 

80539 Miinchen 

http: / /www .dgfi.badw.de - 

GerIIlany 

Geodatisches Institut der Universitat Bonn 

Nussallee 17 

Germany 

http://giub.geod.uni-bonn.de/vlbi 

D-53115 Bonn 

Max-Planck-Institute for Radioastronomy 

Auf dem Huge1 69 

53121 Bonn 

Germany 

http://www .mpifr-bonn.mpg.de 

Agenzia Spaziale Italiana 

Centro di Geodesia Spaziale 

C.P. Aperta 

Ctr.da Teriecchia 

75100 Matera 

http://www.asi.it 

Italy 

Istituto di Radioastronomia, Bologna , Via P. Gobetti 101 

40129 Bologna 

http: / /www .ira.cnr .it 

Italy i 

Istituto di Radioastronomia, Medicina 

C.P. 14 

40060 Vilafontana 

Bologna 

Italy I http://www.ira.cnr .it I 

Istituto di Radioastronomia del CNR, Stazione VLBI di Noto 

C.P. 141 

1-96017 Noto SR 

http://www .ira.noto.cnr .it 

Italy 

IVS 2003 Annual Report 283 
Contributing Institutions 

Geographical Survey Institute 

Kitasato 1 Tsukuba 

Ibaraki 

Japan 

http: //vldb.gsi.go.jp/sokuchi/vlbi/english/ 

Kashima Space Research Center, Communications Research Laboratory 

893-1 Hirai 

Kashima 

Ibaraki 314-0012 

Japan 

http://www.crl.go.jp/ka/index.html 

Forsvarets forskningsinstitutt (FFI) (Norwegian Defence Research Establishment) 

FFI/E 

Box 25 

2007 Kjeller 

Norway 

http: / /www .*.no/ 

Geodetic Institute, Norwegian Mapping Authority 

Kartverksveien 

H~nefoss 

Norway 

http://www.statkart.no 

The Institute of Applied Astronomy, Russian Academy of Sciences 

nab. Kutuzova 10 

St. Petersburg 

191187 

Russia 

http: / /www.ipa.nw.ru 

Sobolev Astronomical Institute of St. Petersburg University 

Universitetskii pr. 28 

Starii Peterhof 

St. Petersburg 

198504 

Russia 

http://www.astro.spbu.ru 

HartRAO, NRF 

PO Box 443 

Krugersdorp 

1740 

South Africa 

http://www.hartrao.ac.za 

284 IVS 2003 Annual Report 
Contributing Institutions 

Observatbrio Astronbmico Nacional 

Apartado 1143 

E28800 Alcalti de Hemes 

Spain 

http://www.m.es/ 

I Onsala Space Observatory (OSO) 

SEX39 92 

Onda 

Sweden 

http://www .oso.chalmers.se 

Experimental Branch of Sea Hydrophysical Institute of NAS of the Ukraine 

Katsively 

Yalta Crimea 98688 

Ukraine 

Lab of Radio Astronomy of Crimean Astrophysical Observatory 

RT-22 

Katsively 

Yalta Crimea 98688 

Ukraine 

http://www .crao.crimea.ua 

Main Astronomical Observatory, National Academy of Sciences of Ukraine 

Main Astronomical Observatory 

27 Akademika Zabolotnoho St. 

Kiev 

03680 

Ukraine 

http://www.mao.kiev.ua 

I 

Gilmore Creek Geophysical Observatory 

NOAA/NESDIS CDA Station 

GCGO/VLBI 

1300 Eisele Rd 

Fairbanks, Alaska 99712 

USA 

http://www.fcdas.noaa.gov 

Jet Propulsion Laboratory, California Institute of Technology 

Mail Stop 238-600 

4800 Oak Grove Dr. 

Pasadena, CA 91109 

USA 

http://www.jpl.nasa.gov 

IVS 2003 Annual 285 
Contributing Institutions 

Kokee Park Geophysical Observatory 

Kokee State Park 

P.O. Box 538 

Waimea, Hawaii 96796 

USA 

MIT Haystack Observatory 

Off Route 40 

Westford, MA 01886 

USA 

http://www.haystack.mit.edu-/ 

NASA Goddard Space Flight Center 

Code 926 

Greenbelt, MD 20771 

USA 

http:/ /lupus.gsfc.nasa.gov 

US. Naval Observatory 

3450 Massachusetts Ave. NW 

Washington, DC 20392 

USA 

http://www.usno.navy.mil 

~ 

286 IVS 2003 Annual Report 
List of Acronyms 

List of Acronyms 

AC 

ACU 

AGU 

AIPS 

ANU 

APSG 

APT 

ARIES 

ARO 

AS1 

ATA 

ATM 

ATNF 

BBC 

BIPM 

BKG 

CACS 

CAS 

CAY 

CDDIS 

CDP 

CGS 

CIP 

cms 

CNR 

CNRS 

CNS 

CORE 

CRAAE 

CRAAM 

CRESTech 

CRF 

CRL 

CSA 

CTVA 

CUTE 

DAR 

DAS 

DASOS 

DAT 

DeltaDOR 

DFG 

Analysis Center 

Antenna Control Unit 

American Geophysical Union 

Astronomical Image Processing System 

Australian National University (Australia) 

Asia-Pacific Space Geodynamics program 

Asia Pacific Telescope 

Astronomical Radio Interferometric Earth Surveying program 

Algonquin Radio Observatory (Canada) 

Agenzia Spaziale Italiana (Italian Space Agency) (Italy) 

Allen Telescope Array 

Asynchronous Transfer Mode 

Australia Telescope National Facility (Australia) 

Base-Band Converter 

Bureau Intemacional de Poi& et Mesures (France) 

Bundesamt fiir Kartographie und Geodbie (Germany) 

Canadian Active Control System 

Chinese Academy of Sciences (P.R. China) 

Centro Astron6mico de Yebes (Spain) 

Crustal Dynamics Data Information System (USA) 

Crustal Dynamics Project 

Centro di Geodesia Spaziale (Italy) 

Celestial Intermediate Pole 

Centre National d'Etudes Spatiales (France) 

Consiglio Nazionale delle Ricerche (Italy) 

National Center for Scientific Research (France) 

Communication, Navigation and Surveillance Systems, Inc. 

Continuous Observations of the Rotation of the Earth 

Center for Radio Astronomy and Space Applications (Brazil) 

Centro de MeAstronornia e Astrofkca Mackenzie 

Centre for Research in Earth and Space Technology (Canada) 

Celestial Reference Frame 

Communications Research Laboratory (Japan) 

Canadian Space Agency (Canada) 

Canadian Tkansportable VLBI Antenna 

CRL and University Telescopes Experiment (Japan) 

Data Acquisition Rack 

Data Acquisition System 

DAS Operating System 

Digital Audio Tape 

Delta Differenced One-way Range 

Deutsche Forschungsgemeinsch& (Germany) 

IVS 2003 Annual Report 287 
List of Acronyms 

DFN 

DGFI 

DGK 

DLR 

DOMES 

DORIS 

DRAGON 

DRAO 

DSIF 

DSN 

DSS 

DVLBI 

ECMWF 

EGAE 

EGS 

ENSG 

ENS0 

ENVIS AT 

EOP 

ERP 

EU 

e-VLBI 

EVN 

FCN 

FESG 

FFI 

FGS 

FS 

FTP 

FWF 

GA 

GALAXY 

GAPE 

GARNET 

GARR 

GARS 

GGAO 

GCGO 

GeoDAF 

GFZ 

GIUB 

GLONASS 

GLORIA 

GMST 

Deutsches ForschungsNetz (Germany) 

Deutsches Geodatisches ForschungsInstitut (Germany) 

Deutsche Geodatische Kommission (Germany) 

German Aerospace Center 

Directory Of MERIT Sites 

Doppler Orbitography by Radiopositioning Integrated on Satellite 

Dynamic Resource Allocation through GMPLS over Optical Networks 

Dominion Radio Astrophysical Observatory (Canada) 

Deep Space Instrumentation Facility 

Deep Space Network 

Deep Space Station 

Differential VLBI 

European Center for Medium Range Weather Forecasting 

Experiment Guided Adaptive Endpoint 

European Geophysical Society 

L’Ecole Nationale des Sciences Gbgraphiques 

El-Nifio/Southern Oscillation 

ENVIronment SATellite 

Earth Orientation Parameters 

Earth Rotation Parameters 

European Union 

Electronic VLBI 

European VLBI Network 

Free Core Nutation 

Forschungseinrichtung Satellitengeodikie (Germany) 

Forsvarets ForskningsInstitutt (Norwegian Defence Research Establishment) (NorForschungsgruppe Satellitengeodikie (Germany) 

Field System 

File Transfer Protocol 

Austrian Science Fund 

Geoscience Australia (Australia) 

Giga-bit Astronomical Large Array with cross connect 

Great Alaska and Pacific Experiment 

GSI Advanced Radiotelescope NETwork (Japan) 

Gruppo per 1’Armonizzazione delle Reti della Ricerca (Italy) 

German Antarctic Receiving Station (Antarctica) 

Goddard Geophysical and Astronomical Observatory (USA) 

Gilmore Creek Geophysical Observatory (USA) 

Geodetical Data Archive Facility (Italy) 

GeoForschungsZentrum (Germany) 

Geodetic Institute of the University of Bonn (Germany) 

GLObal NAvigation Satellite System 

GLObal Radio Interferometry Analysis 

Greenwich Mean Sideral Time 

way) 

288 IVS 2003 Annual Report 
List of Acronvms 

GPS 

GSD 

GSFC 

GSI 

GST 

GeoDAF 

HastRAO 

HTSI 

IAA 

IAG 

IAU 

ICRF 

IDS 

IERS 

IETF 

IGFN 

IGG 

IGN 

IGS 

ILRS 

IMF 

INPE 

IRA 

IRIS 

ISAS 

ITIS 

ITRF 

ITSS 

IUGG 

IVS 

JADE 

JARE 

JAXA 

JGR 

JIVE 

JPL 

KPGO 

KSP 

KSRC 

LAGEOS 

LAREG 

LBA 

LEA 

LLR 

LOD 

Global Positioning System 

Geodetic Survey Division of Natural Resources Canada (Canada) 

Goddard Space Flight Center (USA) 

Geographical Survey Institute (Japan) 

Greenwich Sideral Time 

Geodetical Data Archive Facility (Italy) 

Hartebeesthoek Iio Astronomy Observatory (South Africa) 

Honeywell Technology Solutions Incorporated (USA) 

Institute of Applied Astronomy (Russia) 

International Association of Geodesy 

International Astronomical Union 

Internatiod Celestial Reference Frame 

International DORIS Service 

International Earth Rotation Service 

Internet Engineering Task Force 

Italian Space Agency GPS Fiducial Network (Italy) 

Institute of Geodesy and Geophysics (Austria) 

Instituto Geogr5fm~ Nacional (Spain) 

International GPS Service 

International Laser Ranging Service 

Isobaric Mapping Function 

Instituto Nacional de Pesquisas Espaciais (Brazil) 

Istituto di WoAstronomia (Italy) 

International Radio Interferometric Surveying 

Institute of Space and Astronautical Science (Japan) 

Istituto di Tecnologia Informatica Spaziale (Italy) 

International Terrestrial Reference Frame 

(Raytheon) Information Technology and Science Services (USA) 

International Union of Geodesy and Geophysics 

International VLBI Service for Geodesy and Astrometry 

JApanese Dynamic Earth observation by VLBI 

Japanese Antarctic Research Expedition (Japan) 

Japan Aerospace Exploration Agency (Japan) 

Journal of Geophysical Research 

Joint Institute for VLBI in Europe 

Jet Propulsion Laboratory (USA) 

Kokee Park Geophysical Observatory (USA) 

Key Stone Project (Japan) 

Kashima Space Research Center (Japan) 

LAser GEOdynamic Satellite 

Laboratoire de Recherches en Gbdbie (France) 

Long Baseline Array (Australia) 

Lab of Ephemeris Astronomy (Russia) 

Lunar Laser Ranging 

Length Of Day 

IVS 2003 Annual Report 289 
List of Acronyms 

LSF 

LSGER 

MA0 

MBH 

MIT 

MLRO 

MOBLAS 

MODEST 

MPI 

MPIfR 

MRO 

MTLRS 

NAO 

NAOJ 

NASA 

NCAR 

NCEP 

NEOS 

NESDIS 

NGS 

NICT 

NIPR 

NMF 

NNR 

NNT 

NOAA 

NRAO 

NRCan 

NTT 

NVI 

OAN 

OPAR 

OPC 

os0 

POLARIS 

PRARE 

RAS 

RDV 

REPA 

RFI 

ROEN 

RRFID 

RTP 

SEFD 

SGL 

Large Scale Facility 

Lab of Space Geodesy and Earth Rotation (Russia) 

Main Astronomical Observatory (Ukraine) 

Mathews/Buffett/Herring Nutation Model 

Massachusetts Institute of Technology (USA) 

Matera Laser Ranging Observatory (Italy) 

MOBile LASer 

MODel and ESTimate 

Max-Planck-Institute (Germany) 

Max- Planck-Inst i t Ute for Radioas t ronomy (Germany) 

Metsaovi Radio Observatory (Finland) 

Modular Transportable Laser Ranging System 

National Astronomical Observatory (Japan) 

National Astronomical Observatory of Japan (Japan) 

National Aeronautics and Space Administration (USA) 

National Center for Atmospheric Research (USA) 

National Centers for Environmental Prediction (USA) 

National Earth Orientation Service (USA) 

National Environmental Satellite, Data, and Information Service (USA) 

National Geodetic Survey (USA) 

National Institute of Information and Communications Technology 

National Institute of Polar Research (Japan) 

Niell Mapping Function 

No-Net-Rotation 

No-Net-Translation 

National Oceanic and Atmospheric Administration (USA) 

National Radio Astronomy Observatory (USA) 

Natural Resources Canada (Canada) 

Nippon Telegraph and Telephone Corporation (Japan) 

NVI, Inc. (USA) 

Observatorio Astron6mico Nacional (Spain) 

Paris Observatory (France) 

Observing Program Committee 

Onsala Space Observatory (Sweden) 

POLar motion Analysis by Radio Interferometric Surveying 

Precision RAnge and Rangerate Experiment 

Russian Academy of Sciences (Russia) 

Research and Development sessions using the VLBA 

REsidual Plotting and Ambiguity resolution 

Radio Frequency Interference 

Wdio-Observat6rio Espacial do Nordeste (Brazil) 

Radio Reference Frame Image Database 

Real-Time Protocol 

System Equivalent Flux Density 

Space Geodynamics Laboratory (Canada) 

290 

~~ 

IVS 2003 Annual Report 

~~ ~~~ 
List of Acronyms 

SHAO 

SINEX 

SKA 

SLR 

SNAP 

SPbU 

SRTM 

STDN 

SWT 

TAC 

TAO 

TDC 

TECU 

TEMPO 

TIGO 

TOW 

TRF 

TUM 

UAO 

UDP 

URSI 

USNO 

UT1 

UTC 

vcs 

VERA 

VLBA 

VLBI 

VMF 

VSI 

VSOP 

VTEC 

VTM 

VTRF 

WAC0 

WVR 

www 

ZTD 

ZWD 

Shanghai Astronomical Observatory (China) 

Solution INdependent Exchange format 

Square Kilometer Array 

Satellite Laser Ranging 

Standard Notation for Astronomical Procedures 

Saint-Petersburg University (Russia) 

Shuttle Radar Topography Mission 

Satellite Tracking Data Network 

SW Technology (USA) 

Totally Accurate Clock 

Telecommunications Advanced Organization (Japan) 

Technology Development Center 

Total Electron Content Units 

Time and Earth Motion Precision Observations 

Transportable Integrated Geodetic Observatory (Germany, Chile) 

Technical Operations Workshop 

Terrestrial Reference Frame 

Technical University of Munich 

Urumqi Astronomical Observatory (China) 

User Datagram Protocol 

International Radio Science Union 

U. S. Naval Observatory (USA) 

Universal Time 

Coordinated Universal Time 

VLBA Calibrator Survey 

VLBI Exploration of Radio Astrometry 

Very Long Baseline Array (USA) 

Very Long Baseline Interferometry 

Vienna Mapping Functions 

VLBI Standard Interface 

VLBI Space Observatory Program 

Vertical Total Electron Content 

Vienna TEC (Total Electron Content) Model 

VLBI Terrestrial Reference Frame 

WAshington COrrelator (USA) 

Water Vapor Radiometer 

World Wide Web 

Zenith Total Delay 

Zenith Wet Delay 

IVS 2003 Annual Report 291 
I I OMB NO. 0704-0188 

Form Approved REPORT DOCUMENTATION PAGE 

4. TITLE AND SUBTITLE 5. FUNDING NUMBERS 

International VLBI Service for Geodesy and Astrometry 

920.1 

6. AUTHOR(S) 

Nancy R. Vandenberg and Karen D. Baver, Editors 

7. PERFORMING ORGANIZATION NAME@) AND ADDRESS (ES) 

Goddard Space Flight Center 

Greenbelt, Maryland 2077 1 

9. SPONSORING I MONITORING AGENCY NAME(S) AND ADDRESS (ES) 

National Aeronautics and Space Administration 

Washington, DC 20546-0001 

11. SUPPLEMENTARY NOTES 

N.Vandenberg, NVI, Inc.; K. Baver, Raytheon 

8. PEFORMING ORGANIZATION 

REPORT NUMBER 

2004-00749- 1 

10. SPONSORING I MONITORING 

AGENCY REPORT NUMBER 

TP-2004-2 12254 

12a. DlSTRlBUTlON I AVAILABILITY STATEMENT 1%. DISTRIBUTION CODE 

Unclassified-Unlimited 

Subject Category: 42 

Report available from the NASA Center for Aerospace Information, 

7121 Standard Drive, Hanover, MD 21076-1320. (301) 621-0390. 

This volume of reports is the 2003 Annual Report of the International VLBI Service for Geodesy and 

Astrometry (IVS). The individual reports were contributed by VLBI groups in the international 

geodetic and astrometric community who constitute the components of IVS. The 2003 Annual Report 

documents the work of these IVS components over the period January 1,2003 through December 3 1 , 

2003. The reports document changes, activities, and progress of the IVS. The entire contents of this 

Annual Report also appear on the IVS web site at http://ivscc.gsfc.nasa.gov/publications/ar2OO3. 

13. ABSTRACT (Maximum 200 words) 

14. SUBJECT TERMS 15. NUMBER OF PAGES 

Geodesy, astrometry, VLBI, geophysics, Earth orieintation, very long baseline interferometry, 

interferometry, radio astronomy, geodynamics, reference frames, terrestrial reference frame, 

celestial reference frame, length of day, Eaah system science, Earth rotation. 

296 

16. PRICE CODE 

17. SECURIN CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION 20. LIMITATION OF ABSTRAC 

OF REPORT OF THIS PAGE OF ABSTRACT 

Unclassified Unclassified Unclassified UL 

NSN 7540-01 -280-5500 Standard Form 298 (Rev. 2-89) Prescrlbed by ANSI Std. 239.18 

298-1 02 
INTERNATIONAL VLBl 

SERVICE FOR GEODESY 

AND ASTROMETRY 

IVS Coordinating Center 

NASA Goddard Space Flight Center 

Code 926 

Greenbelt, MD 20771 

htlp: //ivscc.gsfc. nasa.gov 

' ivsccOivscc.gsfc.nas.gov i 

i 

phone: 301 -61 4-5939 

fax: 30 1 -6 1 4-6099