A Novel Polarization Independent Wideband Circuit Analog Absorber Using Crossed Loops

Anotace: In this paper, a polarization independent wideband circuit analog absorber is proposed. The structure consists of two dimensional periodic array of crossed loops embedded with lumped resistors printed on dielectric substrates backed by a metal plate. It offers a -10 dB reflectivity (90%absorptivity) fractional bandwidth of 126.5% (4.6 GHz to 20.45 GHz). The total thickness of the absorber (dielectric+ air gap) is about 0.084λL at the lowest frequency. The effect of different structural parameters on absorption characteristics are studied and presented. The prototype of the proposed absorber is fabricated and the measured responses are in good agreement with simulated results.