A low complexity smoothing algorithm for improved GPS point solutions on board LEO spacecraft

Abstract This paper describes a novel approach for reducing the kinematic position and time errors on GPS receiver in low Earth orbit. For dual-frequency receivers, point solution are dominated by signal-in-space ranging errors, which introduce sharp discontinuities estimates when visibility changes. These may be calculated removed, greatly peaks of at expense introducing slowly varying bias, is estimated removed. The gives detailed description algorithm illustrates its use using historical ephemerides. To demonstrate real-world efficacy, GRACE-FO observations processed proposed approach. Real-time results show reduction error standard deviation 16% to 1.9ns 3D RMS 17% 1.06m. Maximum real-time reduced 26% 32%, respectively. Delayed processing offers greater reductions near 40%.