An ultrawideband RCS reduction antenna design with four reduction mechanisms

Abstract To enhance the antenna’s radar cross section (RCS) reduction bandwidth, this paper, for the first time, integrates four RCS reduction mechanisms into a single antenna structure, achieving ultra-wideband RCS reduction. The design is a dual-layer structure with the top and bottom layers separated by air. The top layer consists of phase cancellation and absorptive metasurface (PCAM), which functions to achieve RCS reduction in the low-frequency range. The bottom layer features a circular slotted patch antenna surrounded by polarization conversion metasurface (PCM). The PCM achieves the RCS reduction of high-frequency through mirror arrangement. Additionally, PCM can be combined with the antenna to create a phase gradient, expanding the reduction bandwidth. The measurements show that the structure can achieve over 6 dB RCS reduction in the 4.3–30.2 GHz under different polarized incidences, with a relative bandwidth of approximately 150.1%. Additionally, the radiation performance of the antenna remains unaffected, and the peak gain reaches 11.27 dBi.