GipsyX/RTGx is the Jet Propulsion Laboratory’s (JPL) next generationsoftware package for positioning, navigation, timing, and Earth science usingmeasurements from three geodetic techniques: Global Nav
AUSGeoid98 data files contain a 2 minute grid of AUSGeoid98 data covering the Australian region, which you can use to interpolate geoid-ellipsoid separations for the positions required.You can use you