星载GPS自主定轨的长期稳定性

通过模拟长达100天的星载GPS伪距观测资料,进行卡尔曼滤波定轨仿真计算．重点研究：1)采用简化的动力学模型与简化状态转移矩阵,是否保证滤波的长期稳定性；2)模型误差矩阵Q的选取对滤波定轨精度的影响；3)与事后最小二乘批处理相比较,在简化模型下自主定轨的精度．同时给出了相应的结论．

The Stability of Autonomous Orbit Determination with Onboard GPS

With simulated onboard GPS data covering 100 days,a test of orbit deter- mination strategy using Kalman filter is performed.The study focuses mainly on three problems:the secular stability of orbit determination by the mean of reduced dynamic model and reduced state transition matrix,the effect of model error covariance Q on the precision of orbit determination,and the precision of reduced Kalman orbit determination by comparing with least square solution.Three conclusions corresponding to these problems are given:The secular stability of orbit determination isn't changed by means of reduced dynamic model and reduced state transition matrix;the selection of model error covariance Q has a loose range;the precision of reduced Kalman orbit determination is at the same level with the precision of least square solution.