Double-polarization frequency selective rasorber based on cross-frame and circle ring slot arrays

A novel double-polarization frequency selective rasorber is presented. Based on the equivalent circuit model, two absorption bands are created at both sides of a transmission window. Cross-frame elements loaded with resistors is employed to provide the window in passband as well as the absorbing characteristic in stopband, meanwhile circle ring slot arrays with lossless characteristic is used to match the impedance of the lossy FSS layer. A simple structure is obtained by combining these two elements. The simulation results indicate that insertion loss of 0.35 dB can be obtained at 5.25 GHz and a bandwidth of 101% for the reflection less than 10 dB is achieved under normal incidence.