Wideband radar cross-section reduction of microstrip patch antenna with split-ring resonators

A novel technique for wideband radar cross-section (RCS) reduction of a microstrip antenna, with the radiating performance preserved at the same time, is proposed and investigated. The design is based on replacing the solid metal ground with the hybrid ground, which consists of suitable compact split-ring resonators. The antenna irradiated by both transverse-electric and transverse-magnetic polarised waves in the normal direction is analysed and investigated. Results show that RCS is dramatically reduced over a wide frequency range from 2 to 20 GHz. By comparison, remarkable RCS reduction of about 11 dB at 20 GHz can be obtained by the proposed strategy. Based on the acceptable effect on radiation features and prominent RCS reduction, the superior performance and reliability of the proposed design are demonstrated.