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The CDDIS provides access to products generated from real-time data streams in support of the IGS Real-Time Service. Two types of products are archived, igt and igc.
The igt solution is a batch combination based on daily clock and sp3 submissions by IGS real-time analysis center. These clock products have been provided since February 2009, shortly after real-time streams were routinely available through the IGS Real-Time Pilot Project and prior to the availability of real-time product streams.
The igc solution is one of the RTS solutions generated by decoding the real-time product streams. The igc files are derived from the IGC01 solution, which uses the real-time data streams that are referred to the satellite center-of-mass (CoM).
- orbit files (igcWWWWD.sp3.Z) contain the decoded orbit and clock results from the IGC01 real time stream at 30 second intervals
- clock solution files (igcWWWWD.clk.Z) consist of decoded clock results from the IGC01 real time stream at 30 second intervals
- solution summary files (ritWWWWD.sum.Z) consist of orbit and clock comparisons of all the AC and combination streams against IGS rapid solution
The CDDIS also provides real-time streaming corrections through its real-time caster. A description of these solutions is available from the IGS RTS website product page.
The starting directory for these files is:
Append the following file names to the starting directory:
WWWW/SSSWWWWD.TYP.Z
as described in the table below.
Code | Meaning |
---|---|
WWWW | GPS week |
SSS | solution type (igc, igt, or rit=comparison summary)
IGC
IGT
RIT
|
D | day of week (0-6, 7 indicates weekly) |
TYP | type of solution (clk=clock correction, sp3=orbit, or sum=solution summary) |
.Z | Unix compressed file |
