Orbit Determining Strategy Analysis for BeiDou Satellite in Different Attitude Control Modes

The BeiDou navigation satellite system have three attitude control modes-yaw-steering(YS) mode, orbit-normal(ON) mode and continuous yaw-steering(CYS) mode. The orbit accuracy and best orbit determination projects for different satellites were a hot topic at present in different time and different attitude control mode, which are researched and whose the dynamical mechanisms is analyzed in this paper. The results are as follows. For BeiDou-2 satellites, multi-satellite precise orbit determination by fixing satellite/station clock offset and extended CODE model (ECOM) 5 SRP should be the best project, user equivalent range errors (UERE) root mean square (RMS) in ON mode is 2.08 m, global satellite laser ranging (SLR) data fitting RMS is ablout 1 m. For BeiDou-3 satellites, multi-satellite precise orbit determination and ECOM 5 SRP should be the best project, UERE RMS in CYS mode is 1.22 m, SLR data fitting RMS is 0.23 m, which is comparable to that in YS mode. For GEO satellites near spring or autumn equinox, multi-satellite precise orbit determination by fixing satellite/station clock offset and ECOM 9 SRP should be the best project, UERE RMS is 0.72 m.