导航卫星自主定轨中系统误差ΔΩ和Δt的消除方法

Method for Eliminating Systematic Error ΔΩ and Δt in Autonomous Orbit Determination of Navigation Satellites

为了消除利用星间距离或速度观测值进行自主定轨时可能存在的卫星星座整体旋转和卫星钟差整体漂移的误差,提出利用单点定位的方法来研究并消除上述两项误差。当导航卫星整体旋转ΔΩ角时,单点定位所求得的测站经度也会偏移ΔΩ角,据此就能用具有精确地面坐标的控制点来测定ΔΩ角。当各卫星钟中均含有系统误差Δt时,利用单点定位所求得的接收机钟差中也会出现同样的误差,通过与标准时间比对就能测定Δt值。算例结果表明,该方法是有效的、可行的。

A method is put forward, which is based on single point positioning to eliminate the satellite constellation revolving errors round the earth and systematic error △Ω in all satellite clocks in making autonomous orbit determination with distance and velocity observations among satellites. When all navigation satellites revolve an angel △Ω round the earth, the longitude of the station given by point positioning will deviate the same angel. According to this principle,we can determine the angel △Ω on ground station with accurate coordinates. When all satellite clocks contain the same systematic error, the clock bias of receiver determined by point positioning also contains the same time error △t. Then the error At can be de-termined by comparing with standard time. The results of several examples show that the methods is feasible and practicable.