Improved guidance law design based on the mixed-strategy concept

The paper summarizes a new approach for missile guidance law design in a noise-corrupted environment. This approach is based on the concept of mixed strategies known from game theory. Two examples demonstrate that this innovative design approach leads to an improved missile performance compared to all guidance laws previously discussed in the open literature. For the sake of simplicity, a two-dimensional version of the terminal phase of a missile-aircraft encounter is adopted. It is assumed that the game takes place in the vicinity of the collision course (see Fig. 1). In this section, the missile and the aircraft will be called pursuer and evader, respectively. Throughout the duration of the game the pursuer measures the relative range R, the closing velocity Vc, and the LOS angle Ji, relative to a reference line. It is assumed that the range and velocity measurements are exact and that the angle is corrupted by noise. The velocity and range information is processed to give an accurate estimate of the time-to-go fgo, while the range and angle information is processed and yields a noisy measurement Z of the evader's relative position perpendicular to the reference line. The input to the estimation process is Z and it is given by: