Abstract：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.
