Capturability Analysis for Biased PN-Based Impact Angle Guidance Law

In this paper, to satisfy the impact angle constraint, a general formulation of the biased proportional navigation guidance is provided. The proposed guidance law is built on the missile-target distance domain (range domain) rather than time domain, which can enhance the guidance accuracy without estimating the flight time. The capture region of the proposed guidance law is fully investigated for all desired impact angles between by studying the behavior of the look angle. The result can provide guidelines on the selection of the desired impact angle based on the initial conditions. For larger impact angles scenarios where the look angle does not converge to zero, the proposed guidance law is readily modified to fulfill the guidance objectives. Numerical simulation results are in complete agreement with theoretical analysis.