Nonlinear Modeling and Optimal Controller Design for Radar Servo System

Radar servo system is a complex system with nonlinearity and coupling. In this paper, the nonlinear mathematical model of radar servo system is established according to the model of executive motor and the load characteristics of radar antenna. Based on the model, an optimal controller for radar servo system is designed by the theory of feedback linearization and linear quadratic regulator (LQR). The feedback linearization approach is employed to realize the linearization and decoupling of the nonlinear model, and LQR is used to design the optimal controller to ensure that the speed tracking error is optimal. The experimental results show that, compared with the traditional feedforward control and feedback control, the designed optimal controller enhances the speed tracking accuracy of radar servo system, while suppressing the load disturbance more effectively.