Frequency-Selective Rasorber for Wideband Transmission Based on Hybrid Resistive Sheet With Harmonic Suppression
Yuxu Chen, Guobin Wan, Xin Ma, Bin Fu, Xin‐Hui Jiao
Abstract
To break through the limitation of harmonic loss on transmission bandwidth, a novel frequency-selective rasorber (FSR) for wideband transmission is present in this article. The FSR is composed of two subsets: an absorption-transmission (A-T) rasorber and a transmission-absorption (T-A) rasorber. The A-T rasorber generates a lower absorption band with harmonic suppression, resulting in a multioctave low insertion loss (IL) transmission window. The harmonic suppression principle of the resistive sheet of the A-T rasorber is described and analyzed in detail, and the corresponding equivalent circuit model is developed to further comprehend the underlying mechanism. The T-A rasorber is designed for a customized upper absorption band. By combining the two subsets, an absorption-transmission-absorption rasorber with wide and low IL passband is obtained. Simulation shows that the −1 dB passband located within the absorption bands ranges from 5.93 to 18.34 GHz with 102% relative bandwidth. Then a linear polarization insensitive FSR extended from the proposed one is discussed. Finally, a prototype with 16 × 16 unit cells is fabricated and measured to validate the design.