## 1999-03-12

# CIVIL GPS SERVICE INTERFACE COMMITTEE,

# INTERNATIONAL INFORMATION SUBCOMMITTEE

## Minutes from the 7^th^ European IISC-meeting in Sweden on 3-4 December 1998

Lotti Jivall, Bo Jonsson and Martin Lidberg, National Land Survey of
Sweden

## INTRODUCTION

The seventh European meeting of the International Information
Sub-Committee (IISC) of the Civil GPS Service Interface Committee
(CGSIC) was held on 3-4 December 1998 in Gavle, Sweden and was hosted by
the National Land Survey of Sweden. The agenda for the meeting can be
found in Annex 1.

The purpose of the meeting was to address the Plans and Policies for
GPS, and discuss the issues concerning GPS, GLONASS and other Satellite
Based Augmentation Systems. Briefings on Services, Projects, Studies and
Applications of satellite techniques were presented. Industrial aspects
of Satellite Based Navigation and Positioning Systems and Services,
Applications and User requirements were also addressed.

103 participants, see Annex 2, attended the meeting and came from the
following 15 nations: Belgium, Czech Republic, Denmark, Finland,
Germany, Latvia, Monaco, Netherlands, Norway, Poland, Russia, Sweden,
United Kingdom, and the United States of America.

The meeting was divided into the following four working sessions:

-   Policies and Status of Satellite and Augmentation Systems, Session
    chair: Capt. James Doherty, US Coast Guard Navigation Center

-   GPS Industry, Session chair: Mike Swiek, US GPS Industry Council

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-   Transport applications, Session chair: Mike Savill, Northern
    Lighthouse Board, Scotland

-   Non-Transport applications, Session chair: Bo Jonsson, National Land
    Survey of Sweden

Additionally there were Opening and Closing Sessions, Technical Tours at
National Land Survey combined with a GPS receiver exhibition, a poster
display, a GPS receiver exercise and also a buffet. On December 5th a
Technical Tour was arranged to the GPS radio beacon station Nynashamn
and to the SWEPOS station Lovo

## OPENING SESSION

The Deputy Director General **Stig Jönsson**, National Land Survey of
Sweden welcomed all the participants to Gavle. He gave a very short
overview of the tasks of the National Land Survey and the on-going
GPS-activities. Finally he stressed the importance of the information
exchange at the CGSIC- and IISC-meetings for the development of the GPS
activities in Sweden and wished all participants a successful meeting in
Gavle

The chair of the International Information Subcommittee **Mike Savill**
welcomed the participants to the seventh European meeting of
International Information Subcommittee. He recognised the contribution
of the Swedish Land Survey to the Civil GPS Service Interface Committee
and their work to arrange, organise and host this meeting.

He also acknowledged the direct support of this meeting from the US
Authorities and the European Community and then introduced the following
representatives:

-   Joe Canny, chair of the Civil GPS Service Interface Committee, US
    Department of Transportation (DOT).

-   Jim Doherty, deputy chair of the Civil GPS Service Interface
    Committee, US Coast Guard

-   Rebecca Casswell, executive secretary of the Civil GPS Service
    Interface Committee, US Coast Guard

-   Hank Skalski, US Department of Transportation liaison to the Air
    Force Space Command

-   Fiona McFadden, The European GNSS Secretariat in Brussels

-   Mike Swiek, the US GPS Industry Council

Mike Savill said that independently of the on-going formal BI-lateral
discussions between the US, Europe, Japan and Russia there is a need to
maintain contacts at an informal level between civil users in different
countries concerned with the deployment and operation of GPS, GNSS and
GLONASS. Therefore it is natural at this meeting of the United States
IISC to allude to other topics such as GNSS1, GNSS2 and GLONASS.

The IISC is in progress of restructuring and George Weber from the
Federal Agency for Cartography and Geodesy, Frankfurt recently became
one of the four regional vice chairs who cover Europe, North America,
Japan and the Far East. Regrettably George Weber, the European region
vice chair, was unexpectedly unable to attend this meeting and he asked
Mike Savill to convey his sincere apologies and best wishes for a
successful and objective meeting.

Finally Mr Savill said that the representatives of the CGSIC and IISC
would be grateful for any feedback, suggestions or ideas on how to
further improve the effectiveness of the IISC and that he looked forward
to a most successful objective meeting in a most appropriate location.

Captain **Jim Doherty**, deputy chair of the Civil GPS Service Interface
Committee gave a short update for the Civil GPS Service Interface
Committee. He reviewed the committee structure and how the CGSIC
supports the Interagency GPS Executive Board (IGEB). The committee has
over 500 members from 56 countries. The CGSIC has been very useful in
pushing for answers to issues, such as the 1024th week rollover. In
addition, the membership assists the US government to compile user
requirements for the next generation of satellites.

## 3. SESSION 1: POLICIES and STATUS of SATELLITE and AUGMENTATION SYSTEMS 

Joe Canny gave an update of the **DOT Policy and Planning on** GPS. The
Interagency GPS Executive Board decided in March 1998 to add a 2nd civil
signal to L2 and a 3rd signal on the Block IIFs that can support
Safety-of-Life needs. Options for the 3rd signal are still examined and
the decision is delayed, but there will not be any negative impact
because the acquisition of the next group of IIFs is also delayed.

Japan and US have agreed on a joint statement for co-operation in the
use of GPS. Negotiations are going on between US and Europe concerning
GPS/GNSS related issues.

The funding structure for the sustainment of constellation,
augmentations and enhancements is being considered by IGEB in order to
avoid jeopardising of the GPS modernisation. The Department of
Transportation in consultation with the Department of Defence (DOD) is
carrying out an evaluation of the vulnerability of the US transportation
infrastructure reliance on GPS. The FAA (Federal Aviation
Administration) is working on an independent GPS/WAAS risk assessment
for civil aviation.

Finally Mr. Canny reported on the preparations for the World Radio
Conference in 2000 (WRC 2000) concerning the protection of the L-band
from non-ARNS systems and on the nation-wide US DGPS network.

**GNSS: The European Viewpoint,** was presented by Fiona McFadden. The
European GNSS approach consists of the two phases GNSS1 and GNSS2. The
European Tripartite Group (ETG), consisting of Eurocontrol, European
Space Agency (ESA) and European Commission (EC), collaborates on the
development of the European GNSS. The European GNSS Secretariat is
co-ordinating the GNSS activities.

The GNSS1 concept consists of GPS, GLONASS, Satellite Based Augmentation
Systems (SBAS), Ground Based Augmentation Systems (GBAS) and User
Equipment Hybridisation & Processing (ABAS). In Europe the SBAS
component is EGNOS (the European Geostationary Navigation Overlay
System), in US WAAS (the Wide Area Augmentation System) and in Japan
MSAS (Multi - Satellite Augmentation System).

The GNSS2 concept consists of a full civilian navigation system and
there are three approaches for the realisation of this system: joint
development by all players, one or more major partners for Europe, or
independent development by Europe. The GNSS2 FORUM is working during the
time period July -- December 1998 in order to support the EC decision
making process. EC and ESA studies are also addressing technical issues.
Decision on the option to be pursued will be taken in early 1999.

Vadim Zohlnerov, Deputy Director of the Russian Institute of Navigation
presented **GLONASS: Status and Prospects.** Currently thirteen GLONASS
satellites are in operation.

Concerning most recent GLONASS development, the correction of the
National Standard of UTC (SU) has been conducted. This operation allowed
to reduce a difference between UTC (SU) and GLONASS system down to 1
µsek. The new reference book on PZ-90 presents a new recommended
coordinate transformation between PZ-90 and WGS-84.

The current economic situation certainly effects GLONASS maintenance and
future development. Nevertheless, GLONASS has a high priority in Russia
aerospace development. Despite the current difficulties, the Russian
Government gives support to the GLONASS program based on already
published official documents. The main purpose of the Federal support
program for the use of the GLONASS is to forge development of user
navigation equipment in Russia. Those enterprises, which were able to
recruit foreign partners for joint works on combined GPS/GLONASS
receivers, were the most successful.

There are GLONASS issues that are subject of continuos discussion and
development. GLONASS will improve if the following main issues are
resolved:

\- protection of frequency band from the recently introduced new system
of mobile satellite communications

\- integration of international standard concerning GLONASS use

\- update of the GLONASS constellation to the new generation GLONASS-M
satellites without harming the existing constellation and navigation
characteristics of the system

\- improving reliability and accuracy of timing and positioning

**The Status of the Global Positioning System (GPS) Constellation** was
presented by Hank Skalski. There are twenty-seven operational GPS
satellites on orbit. During 1999 two launches are planned for April 22nd
and during September.

The civilian GPS users are notified about the health and planned
maintenance of the GPS constellation via:

\- Notice Advisory to NAVSTAR Users (NANU)

\- Notice to Airmen (NOTAM

\- Broadcast Notice to Mariners (NM)

\- Satellite Navigation message

Previously there have not been any official directives for reporting and
controlling removal of a satellite from service, but now the 2nd space
operations squadron has explicit guidance.

The \"Guardian Tiger Team\" with civil representation from US Coast
Guard and Federal Aviation Administration has developed guidelines for
the dissemination of information to civil users about the health and
planned maintenance of the GPS constellation e. g. new NANU format,
fixed NANU types, the distribution process for NOTAMs.

Hank Skalski also presented **GPS Modernization and Operational
Issues.** GPS Modernisation enhances GPS to meet Civil Safety-of-Life
and Economic Needs. Key issues are: improved accuracy, availability and
integrity, together with improved protection from interference and to
ensure backward compatibility with existing user equipment.

Modernisation has the two main components: 1) system enhancements and 2)
operational improvements. System enhancements proposals include more
(30+) satellites, improved radiated power, improved timing signal,
augmentations, improved user equipment, integrity channel, 2nd and 3rd
civil signals. Operational improvements are e. g. interference reporting
and resolution, user notification. Interference can happen both
intentional (e. g. jamming) and non-intentional (e. g. out-of-band). The
USCG Navigation center (NAVCEN) and the FAA National Maintenance
Co‑ordination Centre (NMCC) share the civil reporting responsibilities,
while the military reporting responsibility is with the US Space
Command.

**EGNOS -- the European Satellite Augmentation to GPS and GLONASS** was
presented by Rafael Lucas, ESA, Directorate of Applications, GNSS
Programs. EGNOS (the European Geostationary Navigation Overlay System)
will provide a ranging signal, integrity information and Wide Area
Differential corrections in order to improve accuracy, integrity,
continuity, availability and safety. EGNOS has a multimodal mission, i.
e. Aviation, Maritime, Road and Rail, but is driven by aeronautical
requirements. The Wide area Corrections will enhance the accuracy to
7-10 meters VNSE (Vertical Navigation System Error) for GPS and 4-6
meters VNSE for GPS+GLONASS for precision approach over the territory of
the European Civil Aviation Conference (ECAC) countries.

The fundamentals of EGNOS are the ground segment, the space segment, the
user segment and the support segment. The ground segment consists of
Ranging and Integrity Monitoring Stations (RIMS), Mission and Processing
& Control Centres (MCC), Navigation Land Earth Stations (NLES) and EGNOS
Wide Area Network (EWAN). Geostationary satellites (e. g. INMARSAT III,
AORE/IOR and ARTEMIS) with navigation payloads are the space segment.
Aeronautical, maritime and land user equipment will be developed.

The goal is to have global interoperability between GPS, GLONASS, EGNOS,
WAAS and MSAS.

The following three EGNOS Operational milestones can be noted:

![](media/image1.png)- Test bed. Ranging, Ground Integrity Channel (GIC)
and Wide Area corrections are available from mid 1998.

\- AOC (Advanced Operational Capability). Ranging, Ground Integrity
Channel and Wide Area Corrections will be operational in year 2002.
EGNOS will be used as primary means for En-route, Non-Precision Approach
(NPA), IPV and CAT-I

\- FOC, (Full Operational Capability). AOC + ground/space redundancy
will be available in 2005.

Börje Forssell, Norwegian University of Science & Technology presented
**EUROFIX a Cheap Alternative for Dissemination of DGPS Corrections.**
The concept of EUROFIX is to broadcast DGPS data and integrity
information by modulation of the LORAN-C signal. The Technical
University of Delft (Netherlands) proposed the concept and experimental
transmissions have been done from the Sylt station since 1997.

EUROFIX providers could broadcast accurate DGPS corrections via existing
LORAN-C/Chayka stations (RTCM SC 104) and cover almost the entire
continental Europe and North America. EUROFIX has been shown to offer
excellent DGPS accuracy (\< 3 meter) and integrity. Networked DGPS
performance can be obtained with two or more stations. DGPS can
continuously calibrate LORAN-C/Chayka and the calibrated LORAN-C bridges
GPS coverage gaps.

The benefits of EUROFIX are cost-effective DGPS correction and integrity
services, long range (\<1000 km), emergency broadcast possible, multiple
stations for networked DGPS, easy integration of DGPS and LORAN-C and
dual-rated stations allow increased data rate.

**Nation-wide Differential Global Positioning System (NDGPS) in US** was
presented by Captain Jim Doherty. Leveraging DOD\'s \$12 billion
investment in GPS and DOT´s 40 million in DGPS, the U.S. will soon
blanket the nation with the most accurate and reliable navigation system
the country has ever had. It will be much more than a navigation system,
when it is installed it will be used in a wide array of other
applications as surveying, weather modelling and precise farming.

The Nation-wide DGPS will have the accuracy 1-3 meters in real-time and
5 centimeter using post-processing. The time to an alarm of a
mal-functioning satellite will be 2-5 seconds and the availability
99.999%.

The planning of NDGPS began in January 1997 and the network is based on
a co-operation between a number of governmental agencies, e. g. DOT/OST,
US Coast Guard, Federal Highway Administration, Federal Aviation
Administration.

NDGPS is designed to an international, non-proprietary standard, the
signal will be free and the concept is currently used in 31 countries.
Each NDGPS station will have a maximum operation range of 400 km. DOT
will convert the stations in the Ground Wave Emergency Network (GWEN)
and 67 NDGPS sites will be obtained excluded the present maritime
DGPS-stations. The NDGPS --network will be used for e. g. positive train
control, intelligent transportation system, State&Local government
activities. The benefits to cost ratio is estimated to 152:1

## 4. SESSION 2: GNSS INDUSTRY

Thomas Rehn, the chair of SGIC, presented the **Scandinavian GNSS
Industry Council (SGIC)**, which is a Swedish association of companies
promoting and producing products and systems for satellite positioning
and navigation. The objectives of SGIC are to promote commercial
development of GPS and communicate to industry, User groups and
Authorities. These objectives are achieved by SGIC Internet Website,
arranging seminars, conferences and workshops, attending international
activities on the behalf of the membership, distributing collected
relevant information to members and co-operating with organisations with
complementary objectives. SGIC membership is open both for commercial
companies and agencies and for educational institutions, which are
related to GNSS activities

A number of GNSS products and GNSS services were presented by the GNSS
industry:

**SAAB Dynamics** Lincs -- the data link of the 21st century and
NINS/NILS -- an autonomous navigation and landing system

**Seatex A/S** A combined GPS/GLONASS Position Reference System for DP
(Dynamic Position system) Operations

**Geo++** GNSS-SMART: A technique for Wide Area cm-RTK (Real-Time
Kinematic positioning)

**Volvo** GPS applications at Volvo

**Navdata** IMOS -- a central Integrity MOnitoring System

**Agcom AB** A Local Area RTK (Real-Time Kinematic positioning) System
based on GPS/GLONASS technology

**Teracom** Nation-wide DGPS (Differential GPS) and RTK (Real-Time
Kinematic positioning) Services using the FM radio network

## 5. SESSION 3: TRANSPORT APPLICATIONS

**Fleet management for trucks at Skandia Transport**

An overview of a system for management of 40 trucks at the Swedish
company Skandia Transport was shown. The system, which has been in
operation for one year, consists of the three main components:
GPS-equipment in the vehicles, wireless network with MOBITEX and a
control centre. The use of the system has shown a lot of advantages.

**The Swedish/Finnish radio beacon network**

The first two public DGPS-stations (March 1991) in the world for
maritime navigation belong to the Finnish and Swedish DGPS-networks. The
Finnish network has now five stations in operation + one Estonian
station and the Swedish network consists of eight stations. Tests have
been performed along the Swedish coast to study the conditions for
coverage of double radio beacons.

**Technology leaps to solve air congestion and accommodate traffic --
growth in the 21^st^ century - GPS and data links for Communication,
Navigation and Surveillance.**

The air traffic growth in the territory of the European Civil Aviation
Conference (ECAC) countries requires an efficient Air Traffic Management
in the future. A self-organising air traffic system based on the data
link VDL Mode 4 and GPS allows "free flight" without air traffic
control. Each vehicle can see all other within a certain area and can
choose its own flight way. GPS is used both for positioning and time.

## GPS in the National Rail Administration

The Swedish Rail Administration has used GPS for Control networks since
1989 and has performed some tests with RTK and DGPS for geodetic
measurements along railways. The tests with RTK showed to low accuracy
and insufficient number of available satellites, while the DGPS-tests
turned out to give satisfactory results.

## GPS for fleet management of ambulances

The fleet management system consists of a database with geographical
information combined with the data link MOBITEX and an alarm handling
system. Next year all SOS ambulances in Sweden will report their
locations, determined by GPS, to the management system and soon there
will be a similar fleet management system for fire - brigades as well.
This system will shorten the time before the assistance arrives to those
in distress

## Pilot mounted GPS concept

Mounting the GPS-antenna on the helmet of the pilot and the GPS-receiver
together with a computer in the pilot's leg pocket makes a very flexible
system when using GPS in different aircrafts. The Swedish Defence
Materiel Administration uses this concept for test and verification of
radar systems.

## Some results on long wave DGPS corrections dissemination in the Czech Republic.

The Czech Technical University has been running a DGPS station, equipped
with three receivers, for one year. DGPS corrections are broadcasted in
real time both via the VHF R (B) DS channel and a LF channel. The
corrections are also stored for post-processing. Tests with the
broadcasted DGPS-corrections have been performed at different places in
central Europe.

## The Nordic Institute of Navigation

The Nordic Institute of Navigation is a Norwegian organisation which has
300 members, most of them in Norway. The main task of the Institute is
to follow the development in navigation. The following conferences will
be arranged 1999: MARE 99 in Gothenburg 21-22 April and NORNA 99, on a
Viking Line ferry 23-25 November

## 6. SESSION 4: NON-TRANSPORT APPLICATIONS

## GPS in the Swedish National Forest Inventory

The National Forest Inventory use GPS for location of field spots. The
positioning is done by post-processed differential GPS. Permanent GPS
stations in the SWEPOS network is used as reference stations. Real time
DGPS are not used because many field spots are located where reliable
DGPS corrections are not available. The experience is good, but reliable
positions are not achieved for about 12% of the field plots.

## GPS in Swedish Agriculture

GPS is used for several tasks such as field boundary surveys, soil
sampling, crop scouting, and precision agriculture. Data from yield
sensor and GPS equipment on the harvester are used to produce yield
maps. These maps, combined with data from soil sampling and possibly
crop scanning, determine the amount of fertiliser to be applied on each
spot of the field in a variable fertiliser application. There are about
100 users of yield mapping systems in Sweden today.

## GPS telemetry in wildlife research in Sweden

An animal mounted GPS equipment has been developed and is used on moos,
reindeer, and roe deer in Sweden. The purpose of the positioning part of
the research is to find out why the animals move as they do. Positions
can be downloaded remotely from the equipment, without disturbing the
animal. This system has not been tested on bears. Tests in Canada show
that bears sometimes drop their equipment because of fights and bite.

## Use of GPS for cadastral surveying

DGPS is used for locating and setting out property boundaries in
forested areas. Today the method is cost effective for finding old
boundaries and setting out new ones. But more user-friendly equipment,
less weight and more reliable transmission for the DGPS corrections are
required.

## GPS based height reference system in Poland and Europe

An overview of European GPS campaigns was given. There are 18 different
national height systems in Europe. The GPS campaigns EUREF BAL in 1993
and EUVN in 1997 (European Unified Vertical Network) aimed to get the
relation between these different height systems.

## Five Years of Continuous Observations in the SWEPOS Network

Horizontal movements in the crust caused by the post glacial rebound can
be determined with formal errors at the 0.1 mm/year level, using the
SWEPOS network. The water vapour content, in the troposphere above each
station is estimated, as a by-product, in the positioning computation.
The accuracy in timing can be increased from 100ns today using one
satellite at a time, to 30ns for common view (two stations tracking the
same satellite), and further improved to ≤1ns using the carrier phase.

## Use of GPS for aerial photography

For aerial photography in Sweden GPS is used to navigate within the
photo strips, to enable automatic exposures of the camera at predefined
exposure positions and to determine the position of the airborne camera
at the time of the exposure. The DGPS service EPOS is used for
navigation in Sweden, while absolute GPS are used overseas.

Post-processed GPS are used to get accurate camera co-ordinates for use
in the aerial triangulation, which reduces the need for ground control.

## GPS applications in the field of archaeology and cultural environment

During 1998, several archaeological field teams have been equipped with
simple GPS receivers and the DGPS service EPOS. The mission has been to
identify and position archaeological and cultural sites in the county of
Gavleborg. GPS is good, but needs to be cheaper, more accurate,
particularly in height, and easier to handle.

## 7. POSTERS

## A simple way of transforming coordinates between geodetic reference frames

A simple method has been developed which makes it possible to introduce
a rigorously defined global reference frame without being forced to
abandon the plane grid system in use. The method utilizes the Transverse
Mercator projection and can replace the 7-parameter transformation in
most everyday work within surveying and mapping.

## Results and Achievements of the Long-term Co-operation in Geodesy and Geodynamics Gained by the Sixteen CEI (Central European Initiative) Countries

The Central European Initiative (CEI) has sixteen member states and the
objective of CEI includes initialisation of scientific, economic and
cultural co-operation between the countries of the Central Europe. The
CEI Working Group on Science and Technology has an Earth Science
Committee, which has the three sections Geology, Geophysics and Geodesy.
The report shows the results and achievements of the co-operation in
geodesy and geodynamics in central Europe.

## 8 NATIONAL REPORTS

## GPS in Latvia: Past, Present and Future, 1994-1998

The GPS-campaign EUREF.BAL92 in 1992 was the beginning of large-scale
works for the establishment of a geodetic network in Latvia using GPS.
In the report the GPS work and its application during the period
1994-1998, which have been conducted by Latvian specialists of the
National Surveying Centre of State Land Service, are considered. The
National Surveying Centre was established in 1994.

## GPS Applications and Developments in Poland

Poland contributes to the IGS network (International Geodynamics
Service) with three permanent GPS stations and to the EUREF network with
five stations. The Warsaw University of Technology works as an analysis
center for a Regional network, a part of the EUREF network and he
CERGOP/EXTENDED SAGETT project. The GPS Information Center continues its
work and international/national seminars/conferences on GPS have been
conducted.

## 9 CLOSING of the MEETING

Mr. Frantisek Vejrazka, University of Prag invited to the eight European
IISC-meeting in Prag, Czeh Republic in December 1999.

Proceedings from the sixth European IISC-meeting in Warsaw, December
1997 is available from Mr. Janusz Zielinski, Polish Academy of Sciences,
Warsaw.

Mr Mike Savill thanked all speakers for their contributions to this
meeting and the audience for their participation. On the behalf of the
participants he expressed thanks to National Land Survey for hosting
this meeting, to Mrs. Lena Boberg for her assistance with all practical
details and to Bo Jonsson and his staff for the arrangement of this
meeting.

Finally Mr Savill wished all a safe journey home and said that he is
looking forward to the next meeting in Prag in December next year.

## 9. ACTIVITIES in the EVENING of DECEMBER 3rd

One of the aims of the activities on the evening of December 3rd at the
canteen of the National Land Survey (NLS) was to create opportunities
for information exchange between the participants of the IISC- meeting
in a relaxed atmosphere. An other aim was to stimulate information
exchange between the GNSS industry and the GNSS users.

A practice in transforming coordinates between different reference
systems was conducted using GPS receivers, supplied by the Magellan
company, Sunnyvale, US and Agcom AB, Sweden. A set of coordinates for a
waypoint was supplied in the Swedish reference system (RT 90) and the
task was to walk to that one of the three stations outside NLS which had
the given coordinates in (RT 90) using the GPS receiver. The
GPS-receiver shows the coordinates in the global reference system (WGS
84) and therefore the given coordinates must be transformed in the
GPS-receiver. A small \"reward\" was given to the persons who arrived to
the \"correct\" spot, which was marked with candles.

The Technical tour at the National Land Survey had the following
\"stations\": the control center of the SWEPOS^®^ network, GPS in aerial
photography and historical maps.

The following companies and organisations participated in the
exhibition: Agcom, Ashtech Europe, Enator Telub, Navdata, Noab,
Scandinavian GNSS Industry Council, Spectra Precision, Swedesurvey,
Swedish Maritime Administration, SWEPOS, Teracom.

## 10. TECHNICAL TOUR on DECEMBER 5th

Seventeen persons participated in the Tecnical Tour, which started in
the morning of December 5th from Crystal Plaza Hotel in Stockholm.

The first stop was the DGPS radio beacon in Nynashamn, south of
Stockholm. Nyshamn is one station in the network of eight DGPS radio
beacons, which is based on the \"IALA-standard\" (International
Association of LightHouse Authorities) and operated by the National
Maritime Administration.

After a stop for a small lunch the tour reached the SWEPOS-station Lovo,
west of Stockholm. The SWEPOS network consists of twenty-one stations
and is designed and financed of a co-operation group of Swedish
governmental agencies and companies. National Land Survey operates
SWEPOS.

The tour ended in the afternoon at Crystal Plaza Hotel in a snowy
Stockholm.