Proportional navigation (PN) is a well-known guidance law for a two-vehicle engagement. In the two-vehicle engagement, the miss distance (the closest distance between the two vehicles) is driven to be zero when the line-of-sight (LOS) rate becomes zero. The PN guidance law requires information of the LOS rate and the vehicle velocity, or, if it is available, the closing velocity (the relative approaching speed to the target). However, it is difficult to obtain accurate target information due to its velocity change and uncertain target maneuvers, and so on. For this reason, this paper proposes a guidance law (uncertainty and disturbance-compensated approach) based on the PN guidance law using only LOS rate information without using the closing velocity information. Comparison studies on the proposed guidance law against the optimal guidance law are conducted with some representative simulations.
