GPS-Enhanced Onboard Navigation System (GEONS)

While real-time positioning computed by standard GPS service is adequate for some onboard applications, inherent position discontinuities are not acceptable for high-precision instrument applications, such as view-period prediction and maneuver planning, both of which are computations that require a continuous prediction of the spacecraft state. Real-time positioning also requires simultaneous measurements from four GPS satellites, a mission-limiting factor that must be considered.