Relative impact angle control guidance law to intercept maneuvering target

In this paper, a guidance law with a specified relative flight path angle constraint to intercept a highly maneuvering target is proposed. The RIAC(Relative Impact Angle Control) guidance law is used to enhance the target acquisition and tracking ability of seekers because the relative impact angle decides how clearly the target can be seen by the seeker. The proposed RIAC guidance law is modified from the well-known optimal IAC(Impact Angle Control) guidance law for a non-maneuvering target. By introducing relative impact angle and LOS(Line of Sight) rate into the IAC guidance law, the RIAC guidance law has the form of a biased pure PN(Proportional Navigation) guidance law with the terms of the conventional pure PN and the relative impact angle compensation. The performance of the proposed law was examined using full nonlinear 6-DOF simulations for anti-air missiles against ballistic targets.