基于频率拼接超表面的宽带低RCS高增益天线OA

A novel frequency spliced metasurface consisting of absorptive/transmissive frequency selective surface(ATFSS)and 1-bit polarization conversion metasurface(PCM)is proposed and applied in radar cross section(RCS)reduction for microstrip array antennas.In the low-frequency band,the ATFSS provides good transmission performance within the operating band of the antenna and reduces the RCS of the antenna by absorbing electromagnetic waves outside the band;in the high-frequency band,the RCS reduction bandwidth of the antenna continues to be broadened by the low scattering characteristics of the 1-bit polarization conversion metasurface.The entire frequency spliced metasurface exhibits an absorption-transmission-absorption-scattering frequency response.In addition,the array antenna loaded with frequency-spliced metasurfaces significantly increases the gain compared to a normal microstrip array antenna.Simulation and test results show that the antenna has an impedance bandwidth of 8.65-8.85 GHz and a peak gain enhancement of 2.1 dBi.An out-of-band single-site RCS reduction of more than 6 dB is achieved in the 3.8-21.5 GHz band.