Algorithm for ground-base orbit determination of navigation satellites

Precision of navigation satellite orbit determination is an important factor for the operation of the constellation navigation system. However, there are many problems in the field of navigation satellite ground-base orbit determination, such as low accuracy and high computational complexity. To find potential solutions of these problems, the ground-base orbit determination algorithm of navigation satellites was studied by one-way and passive measuring mode. The state process and the observation model were derived to establish the filter model, with pseudo-range between a monitor station and a satellite as the measurement, and parameters of the satellite clock as elements of the filtering state vector. Based on four GPS satellites in different orbital planes, a two-day simulation was designed to verify the algorithm. Considering the visibility of the satellite, an interruption of measurement between measuring process was introduced, a strategy for restarting the filter was proposed. The simulation results show that the position estimation error is less than 10 meters and the clock bias estimation error is less than 10 ns for all the four satellites. Furthermore, it could keep the previous filtering performance after the filter restarting. All these results indicate that this algorithm is convergent and stable.