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YUMA Almanac File

During scenario start-up, the GSG simulator generates a GPS constellation almanac in the Yuma format. The generated file is named observations/alm_gps.txt and can be retrieved from the observations folder, using:

  • the StudioView File Manager
  • the GSG Web UI
  • the SCPI command set.

Note: This file will be overwritten every time a new scenario is started, so only the YUMA file for the last run scenario will be available.

The almanac file will be empty, if GPS satellites were not included in the latest scenario executed.

The following is an example of one entry in the almanac file:

******** Week 755 almanac for PRN-01 ********

ID: 01

Health: 000

Eccentricity: 5.8191653807E-04

Time of Applicability(s): 233472.0000

Orbital Inclination(rad): 0.9597571420

Rate of Right Ascen(r/s): -8.1828408482E-09

SQRT(A) (m 1/2): 5153.650309

Right Ascen at Week(rad): 1.2710842193E+00

Argument of Perigee(rad): 1.117132574

Mean Anom(rad): –3.0896651067E+00

Af0(s): 1.7600243882E-04

Af1(s/s): 1.3415046851E-11

week: 755