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Acronym Glossary

The following is a glossary of common acronyms. Please email the IGS Central Bureau ( with any additions.
AAC Associate Analysis Center
AC Analysis Center
ACC Analysis Center Coordinator
AECL Atomic Energy Canada Ltd.
AFREF African Geodetic Reference Frame
AIUB Astronomical Institute of the University of Bern, Switzerland
AS anti-spoofing
ASI Agenzia Spaziale Italiana (Italian Space Agency)
AUCK existing IGS station in New Zealand
AWS automatic weather station
BAdW Bayerische Akademie der Wissenschaften, Germany
BEK Bayerische Kommission für die Internationale Erdmessung, Germany
BIFROST Baseline Inferences for Rebound Observations Sea Level and Tectonics (Scandinavian)
BIPM Bureau International des Poids et Mesures, France
BKG German Federal Agency for Cartography and Geodesy (Bundesamt für Kartographie und Geodäsie)
BPE Bernese Processing Engine
BRD broadcast ephemeris
BSW Bernese Software
CA coarse acquisition
CB (IGS) Central Bureau
CBIS Central Bureau Information System
CDDIS Crustal Dynamics Data Information System, USA
CEA Commissariat à l'Energie Atomique
CEGRN Central Europe GPS Reference Network
CEI CERGOP Central European Initiative, Central Europe Regional Geodynamics Project
CGS Matera Space Geodesy Center, Italy
CHAT existing IGS station in New Zealand
CICESE Centro de Investigación Científica y de Educación Superior de Ensenada, Mexico
CISAS Centro Interdipartimentale di Studi e Attivita' Spaziali
CLG Central Laboratory for Geodesy, Sofia
CNES Centre National d'Études Spatiales, France
COD Centre for Orbit Determination
CODE Center for Orbit Determination in Europe
CONGO  Cooperative Network for GIOVE Observation (DLR/GSOC)
COP Code predicted (orbit)
CPU central processor unit
CSR Center for Space Research, USA
DC Data Center
DCE data communication equipment
DEC Digital Equipment Corporation
DGFI Deutsches Geodätisches ForschungsInstitut (German Geodetic Research Institute)
DLR Deutsches Zentrum für Luft-und-Raumfahrt / German 
DORIS Doppler Orbitography and Radiopositioning Integrated by Satellite
DUBO Lac du Bonnet: a new Canadian deformation array site
DUT Delft University of Technology
EMP EMR predicted (orbit)
EMR Energy, Mines, and Resources; now Natural Resources Canada (NRCan)
EOP Earth orientation parameter
ERP Earth rotation parameter
ESA European Space Agency
ESOC European Space Operations Center
ESP ESA predicted (orbit)
ETRS European Terrestrial Reference System
EUR Europe
EUREF European Reference Frame
FAGS Federation of Astronomical and Geophysical Data Analysis Services
FGI Finnish Geodetic Institute
FLIN Flin Flon: a new Canadian deformation array site
GAGE Geodesy Advancing Geosciences and EarthScope
GB  (IGS) Governing Board
GDC Global Data Center
GEO Group on Earth Observations
GEOSS Global Earth Observing System of Systems
GFP GFZ predicted (orbit)
GFZ GeoForschungsZentrum (Research Center for Geosciences), Germany
GGOS Global Geodetic Observing System
GIA Geophysical Institute, University of Alaska
GIBS GPS Information and Observation System, Germany
GIM GIM International, a global magazine for geomatics
GIS Geographic Information Systems
GL Geosciences Laboratory
GLO Abbreviated acronym for GLONASS
GLONASS Globalnaya Navigatsionnaya Sputnikovaya Sistema (Global Navigation Satellite System). Russia
GLOSS Global Sea Level Observing Systems
GMST Greenwich mean sidereal time
GNAAC Global Network Associate Analysis Center
GNO GPS Networks and Operations Group (also GNOG), JPL
GNOS GPS Network Operating System, JPL
GNRT Generalized Near-Real Time, JPL
GNS Institute of Geological and Nuclear Sciences, New Zealand
GNSS Global Navigation Satellite System
GODC Geosciences Laboratory Operational Data Center
GOP Geodetic Observatory Pecny
GPS Global Positioning System
GRGS Groupe de Recherche de Géodésie Spatiale (Research Group in Space Geodesy), France
GSC Geological Survey of Canada
GSD Geodetic Survey Division, Canada
GSF Goddard Space Flight Center, USA
GSI Geographical Survey Institute, Japan
GSOC German Space Operations Center
GZ GEOZUP Company, Kaliningrad, Russia
IAA Institute of Applied Astronomy, Russia
IAG International Association of Geodesy
IAPSO International Association for the Physical Sciences of the Ocean
IAU International Astronomical Union
IBGE Instituto Brasileiro de Geografía e Estatistica, Brazil
ICET International Center for Earth Tides
ICG (United Nations) International Committee on GNSS
ICRF International Celestial Reference Frame
ICSU International Council of Science 
ICSU-WDS World Data System of the International Council for Science
IERS International Earth Rotation Service
IfAG Institute for Applied Geodesy, Germany
IfEN Institut für Erdmessung und Navigation
IFG EUREF Analysis Center
IFRTP Institut Français pour la Recherche et la Technologie Polaire
IGFN Italian GPS Fiducial Network
IGLPS-PP International GLONASS Pilot Project 
IGN Institut National de l'Information Géographique et Forestière (National Institute for Geographic Information and Forestry), France
IGNS Institute of Geological and Nuclear Sciences, New Zealand (see also GNS)
IGP IGS predicted (orbit)
IGR IGS rapid (orbit)
IGS International GNSS Service
IGS International GNSS Service, formerly the International GPS Service
IISC Indian Institute of Science, Center for Mathematical Modeling and Computer Simulation, Bangalore, India
IOC Initial Operating Capability
IOV In-Orbit Validation
IRKT GPS station in Irkutsk, Russia
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITRS International Terrestrial Reference System
IUGG International Union of Geodesy and Geophysics
JOZE IGS permanent GPS station Jozefoslaw, Poland
JPL NASA Jet Propulsion Laboratory, USA
JPP JPL predicted (orbit)
KMS National Survey and Cadastre of Denmark
LA long arc
LDC Local Data Center
LINZ Land Information of New Zealand
LLR lunar laser ranging
LNAAC Local Network Associate Analysis Center
LODR length of day (regularized)
LPT Bundesamt für Landestopographie, Switzerland
M-GEX Multi-GNSS Experiment
MADR GPS station in Madrid, Spain
MINQE Minimum Invariant Quadratic Estimate
MIT Massachusetts Institute of Technology
MSM Multiple Signal Message 
NASA National Aeronautics and Space Administration, USA
NAVSTAR Navigation System Timing and Ranging
NCL University of Newcastle, UK
NEOS National Earth Orientation Service
NEQ normal equation
NGA National Geospatial–Intelligence Agency (USA)
NGS National Geodetic Survey (USA)
NIMA National Imagery and Mapping Agency (formerly Defense Mapping Agency), USA
NKG Nordic Geodetic Commission
NLS National Land Survey of Sweden
NOAA National Oceanic and Atmospheric Administration, USA
NRCan Natural Resources Canada
NRL Naval Research Laboratory
NUVEL-NNR Northwestern University velocity model, no net rotation
OCA Observatoire de la Côte d'Azur
OLG Observatory Lustbühel Graz, Austria
PAD Packet Assembler-Disassembler
PBO United States Plate Boundary Observatory GPS Network 
PGC Pacific Geoscience Centre, Canada
PM polar motion
PNT position, navigation, and timing
PP Pilot Project
PPP Precise Point Positioning
PRN pseudo random number
PSTN Public Switched Telephone Network
QZSS Quasi-Zenith Satellite System, Japan
RDC Regional Data Center
RIGTC Research Institute of Geodesy, Topography, and Cartography
RINEX Receiver-Independent Exchange format
rms root mean square
RNAAC Regional Network Associate Analysis Center
ROB Royal Observatory of Belgium
RTCM Radio Technical Commission for Maritime Services
RTK Real-time Kinematic 
RTS Real-time Service
SA Selective Availability
SCIGN Southern California Integrated GPS Network, USA
SGGS Satellite Geodesy and Geodynamics Systems Group, JPL, USA
SINEX Software-Independent Exchange format
SIO Scripps Institution of Oceanography, USA
SIP SIO predicted (orbit)
SIRGAS Sistema de Referencia Geocéntrico para América del Sur (South American Geocentric Reference System)
SLR satellite laser ranging
SME Subject-Matter Expert
SPC Strategic Planning Committee 
SSC Sets of Station Coordinates
SWOT  Strengths, Weaknesses, Opportunities, and Threats
TCP/IP Transmission Control Protocol/Internet Protocol
TDAF Tracking and Data Analysis Facility
TEC total electron content
TEQC The Multi-Purpose Toolkit for GPS/GLONASS Data
TIGA Tide Gauge Benchmark Monitoring (TIGA) Pilot Project
ToR Terms of Reference
TUM Technical University of Munich / Technische Universität München, Germany
UNAVCO University NAVSTAR Consortium, USA
UNOOSA United Nations Office for Outer Space Affairs
UPAD University of Padova
UPS uninterruptible power supply
USGS U.S. Geological Survey
USNO United States Naval Observatory
UST University of Science and Technology, Ghana
UTC Coordinated Universal Time
VLBI very long baseline radio interferometry
WDC World Data Center 
WETT IGS permanent station in Wettzell, Germany
WG Working Group
WGTN planned IGS station in New Zealand
WRMS weighted root mean square
WUT Warsaw University of Technology, Poland
WWW World Wide Web
YSI Yellow Springs Instruments, USA
ZPD Zenith Path Delay