Geomagnetic autonomous navigation technology of cruise missile based on the unscented Kalman filter

In order to overcome the deficiencies of current navigation technologies of cruise missile, a navigation method using geomagnetic field information was presented. A navigation filter based on the unscented Kalman filter algorithm was designed by taking the international geomagnetic reference field as the geomagnetic field model, the geomagnetic field vectors and the flight height as observed variables, and combining the missile motion model with the geomagnetic field model. The observability and observable degree of the navigation system were analyzed in detail by the observability matrix and the singular value decomposition method. The location and speed of cruise missile were simulated by the navigation filter. The simulated results show that the navigation precision with high order geo-magnetic field model is better than that with low order geomagnetic field model; the smaller the observed noise intensity is, the higher the navigation precision is. The method provides better filter convergence, stability and moderate navigation precision for autonomous navigation in the initial and midcourse phase guidances of cruise missile.