IGS analysis centers provide satellite orbit and clock solutions to the CDDIS using pre-determined schedules, e.g., sub-daily, daily, or weekly, depending upon the data product. The IGS analysis center coordinator retrieves these solutions and produces a combined product, which is then in turn archived at the CDDIS. These combination solutions are considered the official IGS products.

IGS orbit and clock combination solutions are available in three forms: ultra-rapid, rapid, and final. The ultra-rapid product, useful for real-time and near real-time applications, at regular intervals four times per day; the ultra-rapid solution includes both observed and predicted satellite orbits and clocks. The rapid orbit and clock combination is a daily solution available approximately 17 hours after the end of the previous UTC day. The final, and most consistent and highest quality IGS solutions, consists of daily orbit and clock files, generated on a weekly basis approximately 13 days after the end of the solution week. All orbit and clock solution files utilize the Extended Standard Product- 3 (SP3c) format.

Combined clock solutions derived in real-time from AACs using data from the IGS network of real-time data-streaming sites are also available for studies to compare the quality of the real-time products with the IGS ultra-rapid, rapid, and final clock products.

All operational IGS GNSS products (i.e., orbits, station positions, EOP, clock solutions) are available in subdirectories by GPS week.

Solution summary files are provided by the analysis centers in which they describe their analysis methods and strategies and list processing statistics. Descriptions of AC analysis procedures and models used are available from the IGS website.

In 2009 and 2013, the IGS initiated “reprocessing campaigns” (repro1 and repro2 respectively). The IGS analysis centers re-processed the GNSS data from the global network of IGS stations (from 1994 to 2007 for repro1, from 1994 through 2012/2013 for repro2) to produce a fully consistent set of products utilizing the most recent models and updated processing strategies. These reprocessed solutions are available within the weekly subdirectory structure as outlined below, in /repro1 and /repro2 subdirectories.

The starting directory for these files (GPS and GPS+GLONASS solutions) is:

and for GLONASS-only solutions:

Append the following directory and file names to the starting directory:

WWWW/AAAWWWWD.TYP.Z

as described in the table below.

Code	Meaning
WWWW	GPS week
AAA	analysis center name/type of solution
D	day of week (0-6, 7 indicates weekly)
TYP	type of solution
.Z	UNIX compressed file

WWWW/igsWWWWd.clk.Z	Satellite and station clock solution (5 minute) doi: 10.5067/GNSS/gnss_igsclk5_001
WWWW/igsWWWWd.clk_30.Z	Satellite and station clock solution (30 second) doi: 10.5067/GNSS/gnss_igsclk30_001
WWWW/igsWWWWd.cls.Z	Clock solution analysis summary doi: 10.5067/GNSS/gnss_igscsum_001
WWWW/igsWWWWd.erp.Z	Earth orientation parameter solution doi: 10.5067/GNSS/gnss_igserp_001
WWWW/igsWWWWd.sp3.Z	Satellite orbit solution doi: 10.5067/GNSS/gnss_igsorb_001
WWWW/igsWWWWd.sum.Z	Orbit solution analysis summary doi: 10.5067/GNSS/gnss_igssum_001
WWWW/igrWWWWd.clk.Z	GNSS Rapid Combined Satellite and Receiver Clock Solution (5 minute) Product doi: 10.5067/GNSS/gnss_igsrclk_001
WWWW/igrWWWWd.cls.Z	GNSS Combined Rapid Clock Solution Comparison Summary Product doi: 10.5067/GNSS/gnss_igsrcsum_001
WWWW/igrWWWWd.erp.Z	GNSS Rapid Combined Earth Rotation Parameter (ERP) Product doi: 10.5067/GNSS/gnss_igsrerp_001
WWWW/igrWWWWd.sp3.Z	GNSS Rapid Combined Orbit Solution Product doi: 10.5067/GNSS/gnss_igsrorb_001
WWWW/igrWWWWd.sum.Z	GNSS Rapid Combined Orbit Solution Summary Product doi: 10.5067/GNSS/gnss_igsrsum_001
WWWW/iguWWWWd.cls.Z	GNSS Ultra-Rapid Solution Comparison Summary Product doi: 10.5067/GNSS/gnss_igsucsum_001
WWWW/iguWWWWd.erp.Z	GNSS Ultra-Rapid Combined Earth Rotation Parameter (ERP) Product doi: 10.5067/GNSS/gnss_igsuerp_001
WWWW/iguWWWWd.sp3.Z	GNSS Ultra-Rapid Combined Orbit Solution Product doi: 10.5067/GNSS/gnss_igsuorb_001
WWWW/iguWWWWd.sum.Z	GNSS Ultra-Rapid Combined Orbit Solution Summary Product doi: 10.5067/GNSS/gnss_igsusum_001