Estimation of target maneuver acceleration and guidance law implementation in homing terminal guidance

The estimation of guidance information was investigated for homing terminal guidance, based on which the research of the implementation of guidance law was conducted. For the nonlinear mathematical model of terminal guidance, high-gain observer was designed, where the high-gain feedback guaranteed the rapid convergence of the observer error. The information of line-of-sight rate and target maneuver acceleration used in guidance law was estimated via the observer by using the information provided by the missile seeker. The convergence of the observer error was analyzed. In the observer design, the target maneuver was viewed as external disturbance input, so it was not necessary to construct a target maneuver model in the design of the observer, and no statistical assumption was made on target maneuver. The guidance law was implemented by using the estimated signals provided by the observer, and the stability of the closed-loop guidance system was proved. Numerical simulation was conducted, and the simulation results were analyzed, which verified the conclusions given in the paper.