1 INTRODUCTION
The problem of state estimation is important in various applications ranging from target tracking and detection. Many useful estimation approaches have been proposed when there is no information loss in measurements. Multiple-model (MM) estimation approaches turned up to solve the problems which exist in single-model estimation and have been applied in many domains in practice. The main application involves air traffic control, ballistic missile defense and maneuvering target tracking [1] [2]. In MM algorithms, a set of models are set up to approximate the system modes. Interacting Multiple Model Algorithm (IMM) has been demonstrated to be the most cost-effective algorithm among all the MM estimation approaches.