Radar cross section reduction for microstrip antenna using shaping technique

In this paper, radar cross section (RCS) reduction at grazing incidence for microstrip patch antenna using shaping technique is discussed. A rectangular patch antenna is designed as reference. Then shaping is used on the antenna. The radiating edges of the patch antenna are designed as V shape rather than straight line, and the ground plane is shifted up to the same plane of the patch. This mitigates the discontinuity on the surface of the low RCS platform caused by antenna and thus decreases RCS at grazing incidence. The radiation performance does not change too much except some bandwidth reduction. To study the stealth performance of the two antennas at grazing incidence, a platform with relatively low RCS is designed. The reference antenna and the proposed antenna are then mounted on the low RCS platform to study their stealth performance. Results show that the shaping technique is useful for RCS reduction especially for vertical polarization plane wave.