This paper presents a new information fusion filter in integrated navigation. The method can improve the fault-tolerant performance and make well fault detection, isolation and reconfiguration of the integrated navigation system exist. Based on three sensors'(strapdown system, GPS receiver, Doppler radar) information fusion, a fault-tolerant navigation system is designed with this information fusion filter and two-ellipsoid overlap test. Simulation results show that the design is efficient with the soft-failure of gyro, accelerator, GPS receiver and Doppler radar.
