Full-Polarized RCS Enhancement Planar Reflector Utilizing A 4×4 Retrodirective Array

The retrodirective arrays (RDAs) can function as angled reflectors, due to their property to radiate received electromagnetic waves in the opposite direction. However, the radiation mode of the RDAs deteriorates for the case of the polarized directions of incident waves are orthogonal to those of antennas used as array elements. To address such dilemma, RDA utilizing circularly-polarized microstrip antenna as array elements is proposed in this paper. The simulated results demonstrate that the 6 dB beamwidth of the monostatic RCS of the proposed RDA is more than 60°, which is much wider than the equal-sized metal plate. Moreover, the above results are also applicable to the case of linearly-polarized incident wave with different polarization angles.