RCS Synthesis of Array Antenna with Circulators and Phase Shifters and Measurement Method for Deterministic RCS Reduction

This article presents a radar cross section (RCS) reduction method using antennas with circulators and phase shifters. In this method, an antenna connected to a circulator with a phase shifter and an amplifier in its circulation path is utilized, and the amplitude and phase of the antenna mode scattered field, which is the reradiated field of the antenna, are controlled to cancel out the structural mode scattered field. This article proposes array RCS synthesis methods for antenna RCS minimization and for broadening RCS reduction bandwidth and angular range. In addition, a measurement method to determine the amplitude and phase of the antenna mode of each antenna element and the structural mode of the array is proposed for deterministic RCS reduction. The effectiveness of the proposed method is confirmed experimentally in a monostatic case using an eight-element array antenna with circulators and digital phase shifters.