Abstract：This paper describes the technical requirements of passive positioning，constructs the state equation and observation equation of singlebase angular measurement & passive positioning system, theoretically analyzes the principles of different nonlinear filtering methods such as recursive least square method, extended Kalman filter method，unscented Kalman filter method, finite difference extended Kalman filter method, as well as adaptive extended Kalman filter method, and gives the recursive algorithm model. Combined with the specific simulation examples, the simulation analysis is carried out from the aspects of initial value estimation error, measurement error, sampling period and observation noise, and the comprehensive evaluation results of different filtering algorithms are given.
