Elliptical trajectory guidance law with terminal impact angle constraint

A guidance law with terminal impact angle constraint is presented, which can guide a missile in accordance with an elliptical trajectory to adapt its maneuverability. For ballistic missiles or reentry vehicles, maneuverability is limited and varies with the flight altitude and speed. This law can generate a normal overload command which matches the actual available overload, based on the required centripetal force to maintain an ellipse, and achieve the desired terminal impact point and angle. It can be used for different impact angles and from different start points of control. In addition, special forms of the law under certain conditions such as vertical attack or control from ballistic vertex are given. The simulation results applied to the Guided Artillery Rockets show that the guidance law is feasible and effective.