研究基于地磁场的自主导航,建立以卫星轨道动力学方程为基础的系统状态方程,推导出以地磁场矢量为观测量时的观测方程。为解决系统的非线性问题,把UKF引入基于地磁场的自主导航系统中。并用M atlab对基于地磁场的自主导航系统进行仿真,分析滤波周期、初值误差、测量误差对UKF滤波性能的影响,仿真结果表明UKF有很好的收敛性和稳定性。
Autonomous navigation based on geomagnetic field was studied,the system state equations based on the dynamic equation of satellite orbit were built and the observation equations with geomagnetic field vector as the observable were derived.To solve the nonlinear problem of the system,the UKF method for nonlinear system was introduced into the autonomous navigation system based on geomagnetic field.Finally,the simulations were made for the autonomous navigation system based on geomagnetic field with Matlab,and the effects of filtering period,errors of initial values and measurement errors on the performance of UKF were analyzed.The results show that the UKF has good performance in stability and convergence.