Angle constraint biased PNG

In this paper, we propose a new biased proportional navigation guidance (BPNG) to get an arbitrary impact angle against stationary target. The closed form solution of this angle constraint BPNG (named ACBPNG) is derived. And with the solution, we can determine the exact bias for a required impact angle analytically. The solution is shown to be very useful to determine a proper homing guidance condition including initial engaging geometry and missile maneuverability. Because of its handy form to implement and easy solution to analyze, ACBPNG can be the most simple and effective scheme for homing guidance with impact angle constraint. ACBPNG could be applicable to either the system that uses seeker (both active and passive) or the system that does not use seeker.