Multiple-model based methods for target tracking using AESA radars

Abstract

The ballistic missile defense (BMD) system is a system related with the search, detection, tracking, in-terception and destruction of attacking missile. The whole trajectory of ballistic missile can be divided into three phases which are boost phase, midcourse phase and reentry phase. Each phases have own characteristics and have various dynamics. In this thesis, midcourse and reentry phase are considered because of the typical radar limitation which is related to signal to noise ratio (SNR). To achieve the successful missile defense, the radar system should have the flexibility and applicability. The active electronically scanned array (AESA) radar is allowed swift electric steering of the antenna beam, so it is commonly used in BMD systems. In this thesis, AESA radar and Interacting multiple model (IMM) estimator are mainly considered. Unscented Kalman filter (UKF) based IMM filter is used in tracking filter part because ballistic missile motions are highly nonlinear and the aerodynamic parameters are unknown. In this thesis, ballistic coefficient is considered as unknown aerodynamic parameter. If true ballistic coefficient isn’t in the mode parameter range, it is impossible to estimate the ballistic coefficient. So, the mode parameter revision method is suggested.