A new technique for correcting satellite ephemeris errors indirectly observed from radar alimetry

A new technique for correcting ephemeris and other low freqency errors are presented. The satellite's ground track is treated as one time continuous track which repeadtly intersects itself and that a priori functional form of the ephemeris errors is assumed. A conjugate gradient projection algorithm is used to find the unbiased, discrete function of minimum weighted variation which produces the geoid height differences observed at the ground track intersections. The algorithm can be employed to reduce any time dependent, low frequency error present in network type surveys (e.g., oceanographic shipboard and airborne surveys).