Tunable Low-Frequency Broadband Dual-Polarized Rasorber

Abstract

In this paper, a tunable low-frequency broadband metamaterial (MM) dual-polarized rasorber based on slot arrays has been proposed. The structure consists of one air gap sandwiched between top lossy FSS layer and bottom lossless FSS layer, which exhibits a transmission window at 1.70GHz and a 10dB broadband absorption from 0.75GHz to 3.30GHz while the thickness is less than 10% of the free space wavelength at the lowest operating frequency. A switch between absorber and rasorber can be achieved by turning PIN diodes on/off, respectively. We think the proposed rasorber can be applied in low-frequency band stealth technology. The proposed design could also be easily scaled to other frequencies if necessary.