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, announced the U.S. Coast Guard’s Civil GPS Service Interface Committee (CGSIC).

The information is available 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 provide additional information that supplements the antenna gain pattern data previously available.

Note that the GPS III satellite vehicles (SVNs) 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).