This paper presents an analysis of tracking data for spacecraft 'Granat' and 'Interball-1', performed by a radio system 'Kvant-D'. The rage and doppler models are considered. The equations are given, which connect measured radio engineering parameters of tracking system with the spacecraft's state-vectors and antenna's position and speed. There is the description of the local processing algorithms and evaluating of quality of tracking data. There are the evaluations of quality of tracking data that have been carried in 1997.

Theoretical and applied problems of mechanics