IGS Regional GPS Data for Europe from Institute for Applied Geodesy (IFAG)

The International GPS Service for Geodynamics (IGS) supports researchers
who use satellites in the U.S. Defense Department's Global Positioning
System (GPS) for studies in geodynamics. GPS satellites transmit signals
that allow one to determine, with great accuracy, the locations of GPS
receivers. The receivers can be fixed on the Earth, in moving vehicles,
aircraft, or in low-Earth orbiting satellites. The time evolution of
receiver locations allows researchers to study the motions of tectonic
plates, displacements associated with earthquakes, earth orientation, and
other geophysically interesting phenomena. Global Positioning System (GPS)
uses microwave measurements of range (transmitter-to-receiver distance),
accurate to within a centimeter or less, to determine positions of stations
on the Earth's surface. Relative site positions can be measured to within
a centimeter. This system was developed by the U.S. Department of Defense
for military navigation and timing.

IFAG (Institute for Applied Geodesy), Frankfurt, Germany, is the Regional
Data Center for Europe within IGS, the INTERNATIONAL GPS SERVICE FOR
GEODYNAMICS. IGS is a service established by the International Association
of Geodesy (IAG) and officially started its activities on January 1, 1994,
after a successful pilot phase of more than one year. IGS is based on about
40 globally distributed permanent GPS tracking sites, three Global Data
Centers, five Operational or Regional Data Centers, seven Analysis Centers,
and a Central Bureau. Some fifty institutions and organizations contribute
to these activities. Twenty days of data is available on-line at IFAG.
Access to off-line data is by special arrangement.

IGS routinely provides :
* High-quality orbits for all GPS satellites (estimated accuracy better
than 20 cm)
* Earth Rotation Parameters
* Contributions to the determination of the tracking site coordinates in
the International Terrestrial Reference Frame (ITRF), in cooperation
with the International Earth Rotation Service (IERS)
* Phase and pseudorange observations in daily RINEX files for each IGS
tracking site

Every user can login to the IFAG Telnet Access and use the GPS Information
System GIBS. Within this system, the IGS results are available. Telnet
to igs.ifag.de (141.74.240.25), enter Username: gibs and follow the menu.
Telnet access to IFAG is available only for using the GPS Information System
GIBS.

Via FTP, to reach the IFAG data center, FTP to igs.ifag.de (141.74.240.26).
and login anonymous, use your internet address as password, and change to
the directory containing data you want. Following is a list of directories
and file types containing important data:

Directory Filename Description
--------------------------------------------------------------------------

./outdata SSSSDDD0.YYO.Z compressed RINEX obs files
for stations 'SSSS',
day 'DDD', year 'YY'

IFAGDDD0.YYN.Z compressed RINEX nav files
for european sites,
day 'DDD', year 'YY'

CHECK_IMPORT.DAT IFAG data holdings summary
file

./IGSREPORT IGSREPORT.nnn IGSREPORT no 'nnn'
IGSREPORT.INDEX Index file for IGSREPORTs