Double-polarization frequency selective rasorber based on spiral slot array

A double-polarization frequency selective rasorber is presented and demonstrated. Based on the analysis of resonance characteristic, corresponding structures such as spiral slot array loaded with resistors is employed to realize absorption and transmission resonances, respectively. Meanwhile, the array of lossless square ring slot is employed to match the impedance of spiral slot array. A wideband low profile rasorber is obtained by combining these two arrays, which features small insertion loss in passband and high absorption in the two stopbands besides the upper and below the passband. One prototype was fabricated and measured for demonstration. Good agreement can be observed between the measurements and simulation results, indicating the validity of the proposed design strategies.