Dual-polarized frequency selective rasorber with two transmission bands

Abstract

This paper presents a novel dual-polarized frequency selective rasorber (FSR) with two transmission bands and two absorption bands. The FSR is a 2-D structure which is composed of a lossy and a lossless frequency selective surface (FSS) layer. The unit cells of the lossy and FSS layer are both arranged to hexagonal periodic structures. The unit cell of the lossy layer is a combination of a loop with loaded resistors and three folded loops. The loop with resistors is located in the center of the unit cell, and surrounded by three folded loops. The equivalent circuit model shows that the two transmission poles are generated by two parallel LC circuits. The two absorption bands located at the lower side of the first transmission pole and between the two transmission poles are generated by series resonances. The FSR realizes two transmission poles at 6.1 GHz and 10.1 GHz, respectively. The reflection coefficient lower than -10 dB ranges from 3.24 to 10.5 GHz. The lower and higher absorption bands with absorption rates greater than 80% range from 3.3 to 4.97 GHz and 7.42 to 9.03 GHz, respectively. A prototype is fabricated and measured to validate our design and the measurement results match well with the simulation results.