IGS analysis centers provide satellite orbit 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 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, is archived at regular intervals four times per day; the ultra-rapid solution includes both observed and predicted satellite orbits. The rapid orbit 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 files, generated on a weekly basis approximately 13 days after the end of the solution week. All orbit solution files utilize the Extended Standard Product- 3 (SP3c) format.

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, 2013, and 2020, the IGS initiated “reprocessing campaigns” (repro1, repro2, and repro3 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, from 1994 through 2022 for repro3) 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, /repro2, and /repro3 subdirectories.

The starting directory for these files is:

and for GLONASS-only solutions:

At the end of 2022, the IGS made the decision to change the name format going forward of many of its products archived at the CDDIS. A table is available on the IGS website which compares the old and new name formats. The table can be found on the following page:

Name Format Since GPS Week 2238

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

WWWW/AAA0PPPTYP_YYYYDDDHHMM_LEN_SMP_CNT.FMT.gz

as described in the table below.

Code	Meaning
WWWW	GPS week
AAA	analysis center name
PPP	campaign/project specification
TYP	solution type identifier
YYYY	4-digit year
DDD	3-digit day of year
HH	2-digit hour
MM	2-digit minute
LEN	intended product period
SMP	temporal product sampling resolution
CNT	content type
FMT	file format
.gz	gzipped file

Name Format Before GPS Week 2237

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)
HH	2-digit hour (00, 06, 12, 18)
TYP	type of solution
.Z	UNIX compressed file

Though many products are available, the products listed below have permanent DOIs:

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.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_HH_cmp.sum.Z	GNSS Ultra-Rapid Orbit Solution Comparison Summary Product doi: 10.5067/GNSS/gnss_igsucsum_001
WWWW/iguWWWWD_HH.erp.Z	GNSS Ultra-Rapid Combined Earth Rotation Parameter (ERP) Product doi: 10.5067/GNSS/gnss_igsuerp_001
WWWW/iguWWWWD_HH.sp3.Z	GNSS Ultra-Rapid Combined Orbit Solution Product doi: 10.5067/GNSS/gnss_igsuorb_001
WWWW/iguWWWWD_HH.sum.Z	GNSS Ultra-Rapid Combined Orbit Solution Summary Product doi: 10.5067/GNSS/gnss_igsusum_001