An Efficient Method for Multiangle RCS Simulation of Electrically Large PEC Targets

This letter presents an efficient method for multi-angle radar cross section (RCS) simulation of electrically large perfect electric conductor (PEC) targets. The approach is built on an enhanced principle of angular stability in scatterer surface illumination. Specifically, after standard ray tracing at a reference angle, illuminated regions and their reflection orders remain stable across neighboring angles, and the multi-bounce ray paths can be approximated by the same local planes. Therefore, multi-bounce ray paths can be efficiently constructed using the mirror image method (MIM), enabling accurate calculation of induced currents and, consequently, precise scattering field simulations. The method applies to arbitrarily complex-shaped targets, and a multi-window scheme with a stability check mechanism is further introduced to enhance robustness. Simulation results verify the accuracy and efficiency of the proposed method, with significant advantages in simulating electrically large targets.