A monostatic RCS reduction study for an antenna in structural mode at X band

Abstract

In this paper, a radar cross-section (RCS) reduction of a microstrip antenna is investigated both experimentally and numerically. A traditional metal ground plane antenna and a bandstop frequency selective surface (FSS) filter are designed at 5.4 GHz. In order to reduce RCS and reflectivity of the reference antenna, the bandstop filter structure is set up instead of the full metal ground plane. The study observed a wide frequency range between 3 GHz and 14 GHz. The maximum RCS reductions between the reference antenna and the low RCS antenna in-band and out of band are obtained at 9.2 dBsm and 28 dBsm, respectively. The antennas are analysed under different θ–and φ–polarised incidence conditions. Low RCS antenna shows satisfactory results especially at X band in terms of reflectivity and RCS under these angular conditions.