A DUAL-BAND METAMATERIAL MICROWAVE ABSORBER

Abstract

A dual-band metamaterial microwave absorber for X band ( 8-12 GHz) applications is proposed. A unit cell of the absorber consists of an electric LC ( ELC) resonator, a backing ground plate, and an FR4-epoxy substrate with 0.8 mm thickness. To realize efficient space utilization for the dual resonance, an ELC resonator consisting of asymmetric triangle split-ring resonators is adopted. Using effective medium parameters extracted from the S-parameters, the EM behavior is clarified to describe the operating mechanism. The miniaturized dimensions of the unit cell are 8 mm 3 8 mm 3 0.8 mm. The measured results exhibit two absorptivity peaks stronger than 98.5% and FWHMs of 8.4% and 7.25% at 8.2 GHz and 12 GHz, respectively. Additionally, high absorptivity performance is achieved for EM waves from 08 to 608 regardless of the incident angle.