基于接收机钟差约束的地基伪卫星导航改进方法

An improved approach for positioning of ground-based pseudolite navigation system based-on receiver's clock error restriction

采用地基伪卫星对飞行器进行导航时,由于布站场地有限不可避免地会出现定位构型差的情况,当仅用伪距和伪距变率进行定位定速时,若采用典型的单历元卫星定位定速算法,那么对飞行器的定位定速精度就会比较差。通过分析发现,地基伪卫星导航系统用户接收机钟差和钟差变率的求取不准确很大程度上影响了定位定速精度。针对这种情况,提出了通过提高地基伪卫星接收机钟差和钟差变率的求解精度来提高定位定速精度的方法。首先根据接收机钟差和钟差变率的模型得到它们的观测方程,然后将其加入到单历元定位定速方程组中参与定位定速解算,仿真结果表明了该方法的可行性和有效性。

When the ground-based pseudolite navigation system is used for vehicle,there will be some bad geometric configuration situations because of the area restriction for pseudolites. If the traditional single positioning algorithm is used with pseudo range only as usual,the precision of positioning for vehicles will be low. In light of this,this study proposed that the inaccurate solution of receiver＇s clock error affects the precision of positioning to a great extent. For this situation,an improved approach was suggested to obtain a better precision of positioning through increasing the accurateness of solution of receiver＇s clock error. The main idea was to obtain the observation model of the receiver＇s clock error and then adding the model to the positioning equations. The simulation results indicate that the approach is feasible and effective.