IGS Antenna Working Group

Last modification: 01 Nov 2017

IGS antenna files
This file summarizes information concerning the various IGS antenna files available
at ftp://ftp.igs.org/pub/station/general/. Each receiver antenna type in use within theIGS network should be contained in three different files (satellite antennas are onlycontained in the first two of them):

rcvr_ant.tab: naming convention*.atx: phase center corrections
antenna.gra: reference points and dimensions

Phase center corrections are provided in the Antenna Exchange Format (ANTEX)
which is defined in a separate format specification. Information on the other files canbe found in the respective headers. A general description of all files is given below:1)

rcvr_ant.tab
purpose/content: IGS naming conventions for GNSS equipment (receivers,antennas, radomes, satellite antennas); only valid names to be used in IGS sitelogs, RINEX headers, SINEX files, etc.
responsibility: IGS Central Bureau
contact: support@igs.org
requirements for new entries:geodetic equipment relevant to the IGS and users of IGS products withcm-level capabilities

unique hardware model

unique descriptionunchangeable namingconsideration of format specifications

agreement with naming of calibration institutions, if possible

 authorization of manufacturer, if possible
checklist: https://kb.igs.org/hc/en-us/articles/204200287-Checklist-for-RequestingAdditions-to-rcvr-ant-tab2)

igs14_wwww.atx (wwww = GPS week of the last file change)(latest version is symbolically linked to the generic filename igs14.atx forconvenience)
purpose/content: absolute IGS phase center corrections for satellite andreceiver antennas; to be used with the IGS14 terrestrial reference frame which is
closely related to, but not identical with ITRF2014 because the latter is based on
igs08.atx antenna phase center corrections
responsibility: IGS Antenna Working Group
contact: awg@igs.org, arturo.villiger@aiub.unibe.ch
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IGS Antenna Working Group

Last modification: 01 Nov 2017

requirements for new entries (receiver antennas):
antenna name contained in rcvr_ant.tabdefinitions of antenna reference point (ARP) and north reference point(NRP) contained in antenna.gra

consistent phase center offsets (PCOs) and variations (PCVs)

consideration of ANTEX format specifications (e.g., IGS sign convention)

availability of zenith- AND azimuth-dependent calibration values down tothe horizon (with a resolution of at least 5 and 10 degrees, respectively)availability of consistent calibration values for multiple GNSS (at least GPSand GLONASS)in order to guarantee high accuracy for low elevations, the antenna should
be tilted during the calibration procedure

addition of calibrations not matching the above criteria is only possible in a
few exceptional cases (e.g., if a calibration for a combination of an antenna
with a specific radome became available whose effect was ignored within
the IGS before then)replacement of existing values is only allowed in a few exceptional cases(e.g., major model update, reference frame change, etc.) in cooperation
with the IGS Reference Frame Working Group

radome calibrations can only be added for combinations that are not (yet)in use within the IGS (otherwise the addition is a matter of a replacement,
as the calibration for the antenna without the radome was used within theIGS before then)Geo++ GmbH only permits its type mean calibrations to be published in thepublic domain for the antenna types used within the IGS and EPN
networks; calibrations for other antenna types are generally not openly
availableantenna manufacturers are encouraged to provide type mean calibrations
for all their models using one of the available calibration services

where to get approvable calibrations?
(list will be extended as soon as additional institutions meet the requirements)
Geo++ GmbH
http://www.geopp.de/gnpcv-absolute-antenna-calibration-type-correction

Leibniz Universität Hannover, Institute of Geodesy
http://www.ife.uni-hannover.de/antenna-calibration.html

Senatsverwaltung für Stadtentwicklung Berlin, GNSSLandeskalibriereinrichtung
http://www.stadtentwicklung.berlin.de/geoinformation/landesvermessung/landeskalibriereinrichtung/de/kalibrierung_gnss.shtml


University of Bonn, Institute of Geodesy and Geoinformation
http://www.gib.uni-bonn.de/forschung/bew_obj/antennenmesskammer

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IGS Antenna Working Group

Last modification: 01 Nov 2017

procedure for newly launched satellites:antenna name contained in rcvr_ant.tab

as soon as launch date, satellite designations (PRN/SVN number,slot/GLONASS number, etc.) and COSPAR ID are known, a rounded block
mean PCO is added together with the corresponding block mean PCVs, ifavailable

in the case of a new antenna/block generation, manufacturer values haveto be applied for the PCO together with zero PCVs

no earlier than six months after the satellite launch, the block mean PCO isreplaced by an individual offset value from the combination of weekly IGSAnalysis Center SINEX solutions



PCVs for new satellite antenna type: procedure tbd.

intended procedure for major model update:3)

compilation of an unofficial file containing the best possible receiverantenna corrections (regardless of any consistency problems) and updated
satellite antenna PCVs

reprocessing campaign of the IGS Analysis Centers with receiver antennacorrections kept fixed

estimation of consistent satellite antenna z-offsets with the latest reference
frame kept fixed

release of the complete antenna phase center model together with thecorresponding reference frame

antenna.gra
purpose/content: antenna reference point (ARP) definition, north reference point(NRP) definition, physical antenna dimensions
responsibility: IGS Central Bureau
contact: support@igs.org
requirements for new entries:4)

antenna name contained in rcvr_ant.tabauthorization of manufacturer, if possibleeither an antenna drawing or the necessary information for the creation ofthe drawing have to be provided

antex14.txt
purpose/content: ANTEX format definition, IGS antenna file naming convention,
IGS sign convention for PCOs and PCVs
responsibility: IGS Antenna Working Group
contact: awg@igs.org, arturo.villiger@aiub.unibe.ch

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IGS Antenna Working Group

Last modification: 01 Nov 20175)

Old IGS phase center corrections files (no longer maintained)igs08_wwww.atx (wwww = GPS week of the last file change)(latest version is symbolically linked to the generic filename igs08.atx forconvenience)
purpose/content: absolute IGS phase center corrections for satellite andreceiver antennas; to be used with the IGS08/IGb08 terrestrial reference frame
which is closely related to, but not identical with ITRF2008 because the latter isbased on igs05.atx antenna phase center corrections
file is no longer maintained!

igs05_wwww.atx (wwww = GPS week of the last file change)(latest version is symbolically linked to the generic filename igs05.atx forconvenience)
purpose/content: absolute IGS phase center corrections for satellite andreceiver antennas; to be used with the IGS05 terrestrial reference frame which isaligned to, but not identical with ITRF2005 that is based on relative antennaphase center corrections
file is no longer maintained!

igs_01.atx
purpose/content: relative IGS phase center corrections for satellite and receiverantennas (former IGS antenna model igs_01.pcv converted into the ANTEXformat)
file is no longer maintained!

igs_01.pcv
purpose/content: relative IGS phase center corrections for receiver antennas
only (former IGS format)
file is no longer maintained!

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