Novel technique for RCS reduction of circularly polarized microstrip antennas

A novel technique for radar cross section (RCS) reduction of circularly polarized (CP) microstrip antennas is proposed in this paper. By the introduction of several circular and rectangular slots on the ground of the reference CP antenna, RCS of the CP antenna is reduced without effects on the circular polarization performances. Based on the common rectangular CP antenna, two modified antennas are proposed as the examples to validate the novel technique of RCS reduction. The simulated and measured results show that the proposed antennas have lower RCS than the reference antenna while maintaining the same CP performances, which illuminates that the proposed technique is a good candidate for CP antennas with a requirement of RCS control.