Multiple Model Adaptive Evasion Against a Homing Missile

Abstract

Multiple model adaptive evasion strategies from an incoming homing missile are presented. The problem is formulated in the context of an evading target aircraft having imperfect information on the relative state and on the employed guidance law and guidance parameters of the missile. The missile’s guidance strategy is assumed to belong in a finite set of linear guidance laws and to be fixed throughout the engagement. Arbitrary-order linear missile and target dynamics, bounded target control, and nonlinear kinematics are also assumed. The filter used to identify the missile’s guidance strategy is a nonlinear adaptation of the multiple model adaptive estimator, in which each model represents a possible guidance law and corresponding guidance parameters of the attacking missile. Specific limiting cases are carefully analyzed in which the attacking missile uses proportional navigation, augmented proportional navigation, or an optimal guidance law. Matched optimal evasions from these specific cases are also derived and fit into the framework of the multiple model adaptive control approach. For the limiting cases, an alternative reduced-order approach is proposed to save computational resources. Considering noisy bearing-only measurements, the performance of the proposed evasion concepts is compared through a Monte Carlo simulation campaign to the scenario when the target has full knowledge about the attacking missile and the relative state.