Rinex Nav Broadcast Ephemeris File

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The RinexNavFile object provides the capability to read and write Broadcast Ephemeris data to and from a Rinex Navigation file. This is an ASCII file of Broadcast Ephemeris data conforming to the RINEX standard. FreeFlyer supports the RINEX 2 and RINEX 3 formats.


RinexNavFiles (also known as Broadcast Ephemerides) contain position, velocity, and clock information for some Global Navigation Satellite System (GNSS) constellations. The GPS and Galileo constellations both use the RINEX format. FreeFlyer has the ability to read and write RinexNavFiles, but cannot generate new data in this format (Broadcast Ephemeris data can be read in and then written out to a new file, but cannot be simulated independently). The time system is GPS Time, and positions and velocities are in the ECEF reference frame, which FreeFlyer converts into the MJ2000 frame.


Note: Due to its discontinuous nature, Broadcast Ephemeris data should not be used to propagate Spacecraft objects while detecting events using Interval Methods. Instead, the Broadcast Ephemeris should be used to set the initial state of the Spacecraft and then an integration-based propagator, such as an RK89 or Cowell integrator, should be used to propagate it.


More information on the RINEX format can be found in several locations. Two example references are provided below:





Additionally, historical RinexNavFiles and pre-processing utilities can be downloaded from multiple sources; four examples are provided below:







An example of the format of a RINEX 2 Nav file is given below.


    2              NAVIGATION DATA                         RINEX VERSION / TYPE

comb_nav.pl         SOPAC      Sat Aug  2 03:00:09 UTC 2008 PGM / RUN BY / DATE

                BROADCAST EPHEMERIS FILE                   COMMENT            

    SCIGN - Southern California Integrated GPS Network     COMMENT


     SOPAC - Scripps Orbit and Permanent Array Center      COMMENT

   IGPP - Institute of Geophysics and Planetary Physics    COMMENT

        SIO - Scripps Institution of Oceanography          COMMENT

       UCSD - University of California, San Diego          COMMENT


               email: archive@josh.ucsd.edu                COMMENT

                   ftp://garner.ucsd.edu                   COMMENT

                  http://sopac.ucsd.edu                    COMMENT


                                                           END OF HEADER      

2 08  8  1  0  0  0.0 1.981128007174D-04-2.728484105319D-12 0.000000000000D+00

   6.600000000000D+01-1.362500000000D+01 5.521301412937D-09 2.257403702520D+00

  -5.625188350677D-07 8.749986649491D-03 4.982575774193D-06 5.153745389938D+03

   4.320000000000D+05 1.080334186554D-07-1.301406564647D+00 1.695007085800D-07

   9.425145279018D-01 2.740312500000D+02 2.618450595652D+00-8.381063390645D-09

  -4.857345185067D-10 0.000000000000D+00 1.490000000000D+03 0.000000000000D+00

   2.800000000000D+00 0.000000000000D+00-1.722946763039D-08 6.600000000000D+01

   4.319400000000D+05 4.000000000000D+00

2 08  8  1  2  0  0.0 1.980932429433D-04-2.728484105319D-12 0.000000000000D+00

   7.500000000000D+01-1.896875000000D+01 5.449155550630D-09-2.975670304909D+00

  -8.996576070786D-07 8.749276399612D-03 5.079433321953D-06 5.153746816635D+03

   4.392000000000D+05-9.685754776001D-08-1.301467271359D+00 1.210719347000D-07

   9.425119341481D-01 2.727812500000D+02 2.618483343073D+00-8.269273019842D-09

  -3.546576300567D-10 1.000000000000D+00 1.490000000000D+03 0.000000000000D+00

   2.800000000000D+00 0.000000000000D+00-1.722946763039D-08 7.500000000000D+01



An example of the format of a RINEX 3 Nav file is given below.


    3.03           NAVIGATION DATA     M (Mixed)           RINEX VERSION / TYPE

BCEmerge            congo               20200312 004604 GMT PGM / RUN BY / DATE

Merged GPS/GLO/GAL/BDS/QZS/SBAS/IRNSS navigation file       COMMENT

based on CONGO and MGEX tracking data                       COMMENT

DLR/GSOC: O. Montenbruck; P. Steigenberger                  COMMENT

GAUT -1.8626451492e-09 8.881784197e-16 172800 2096          TIME SYSTEM CORR    

GPGA  1.1059455574e-09-8.881784197e-15 259200 2096          TIME SYSTEM CORR    

QZUT -6.5192580223e-09 0.000000000e+00 442368 2096          TIME SYSTEM CORR    

                                                           END OF HEADER      

G01 2020 03 11 00 00 00-3.217491321266e-04-1.239186531166e-11 0.000000000000e+00

    6.300000000000e+01 9.450000000000e+01 4.517331022112e-09 1.043981160977e+00

    5.127862095833e-06 9.483204688877e-03 6.658956408501e-06 5.153631544113e+03

    2.592000000000e+05-9.313225746155e-09-1.831700682783e+00 1.080334186554e-07

    9.788953519263e-01 2.599687500000e+02 7.548638563667e-01-8.405350116571e-09

    4.221604418198e-10 1.000000000000e+00 2.096000000000e+03 0.000000000000e+00

    2.000000000000e+00 0.000000000000e+00 5.587935447693e-09 6.300000000000e+01

    2.590680000000e+05 4.000000000000e+00                                      

G01 2020 03 11 02 00 00-3.218385390937e-04-1.239186531166e-11 0.000000000000e+00

    8.700000000000e+01 1.047812500000e+02 4.534474593353e-09 2.094339367653e+00

    5.282461643219e-06 9.483161265962e-03 6.631016731262e-06 5.153628858566e+03


    9.788996967930e-01 2.611875000000e+02 7.547139482253e-01-8.196769999800e-09

    5.832385799422e-10 1.000000000000e+00 2.096000000000e+03 0.000000000000e+00

    2.800000000000e+00 0.000000000000e+00 5.587935447693e-09 8.700000000000e+01

    2.592180000000e+05 4.000000000000e+00                                      



See Also

RinexNavFile Properties and Methods