An IMM-based method for reentry-phase tracking of unknown ballistic missiles

In this paper, the tracking system which is related to the ballistic missile defense (BMD) is considered. In BMD system, it is necessary to track the fast and unknown objects. Furthermore, priori information about the hostile missile is not provided. Without the priori information like aerodynamic parameters, it is hard to make the filter dynamic model of the hostile missile. To solve this problem, in many researches, IMM filter is selected as a tracking filter of BMD system. But IMM filter itself is not a perfect tool for tracking the unknown target. If the IMM filter mode set does not subsume the true dynamic model, the tracking filter may have large error. So, the mode revision method is suggested. With this method, the IMM mode set is adaptively changed and then subsumes the true dynamic model.