CGSIC Bulletin: GPS-III Satellite Group Delay, Phase Center and Inter-Signal Bias Data for SVN-76 and SVN-77

Lockheed Martin Space has released the GPS-III Satellite antenna phase center data, as well as the group delay and inter-signal correction data for SVN-76 and SVN-77 as measured at the factory.  The information has been posted on the U.S. Coast Guard Navigation Center’s website underneath the IIR/IIR-M antenna pattern data files.

The phase center and inter-signal bias data included in this new release provides additional information that supplements the antenna gain pattern data previously available.

Note that the GPS-III SVs also broadcast the Inter-Signal Corrections (ISCs) in the various LNAV/CNAV messages in accordance with all the external IS/ICDs.  The value that is being broadcast by the on-orbit constellation is not the factory measured ISCs but the ISCs estimated on-orbit by the Stanford Research Institute (SRI).