Research On The Algorithm Of Terminal Nonlinear Ballistic Target Tracking

As the core of missile defense system,target tracking is the basis of the data analysis,recognition and control which has important values during modern warfare.This paper focuses on the problem of tracking and interception of terminal ballistic targets by defense systems and studies the tracking theory and method of terminal ballistic targets.It mainly researches how to establish a target tracking model which matches with the kinematic characteristics of targets and the observation sensor,and nonlinear filtering algorithm of target tracking to achieve the requirements of accurate and real-time.In order to improve the tracking accuracy of the terminal non-linear trajectory target,a new extended measurement algorithm with the measurements of the target's radial velocity and shape parameters is proposed.The main work of this paper is as follows.Firstly,a target tracking model which matches with the kinematic characteristics of targets and the observation sensor is established.The transformation relationships among several coordinates is derived.Then,the target state equation in the Earth-Centered Earth-Fixed coordinate system based on the motion of ballistic targets is obtained and the corresponding target trajectory can also be determined by solving the target moving equation.Secondly,the unscented kalman filter algorithm(UKF)for terminal non-linear trajectory target tracking is presented based on the measurement of the distance and angles of the target.Several typical filtering algorithms are compared and finally the UKF algorithm is chosen as the target tracking filter.Then the root mean square error(RMSE)and cramer-rao lower bound(CRLB)are used to evaluate the performance of the target tracking system.Thirdly,to improve the tracking accuracy of the terminal non-linear trajectory target,a modified filtering algorithm using extended measurements is put forward with the UKF.This paper considers the measurements of radial velocities and shape parameters of terminal ballistic targets using high accuracy sensors.A tracking filtering algorithm for terminal non-linear trajectory targets incorporating the extended measurements is presented and the simulation is performed.At last,it uses RMSE and CRLB to analysis the performance of the system and shows that the extended measurements can improve the tracking accuracy and dynamic convergence characteristics of ballistic targets.