Design of FSS Based Microwave Absorber For Wideband Absorption Applications

Abstract

Microwave absorbers have critical significance due to widely extended applications in defence, electromagnetic compatibility (EMC)/electromagnetic interference (EMI) reduction, anechoic chamber, wireless communication, and different medical applications. Conventional electromagnetic (EM) absorbers have some constraints in practical domain. Instead, advanced FSS absorbers offer a solution to these limitations by controlling the material permittivity and permeability. This work presents the design of planar FSS based broadband microwave (MW) absorber that operates from 8.508 GHz to 16.701GHz, covering the X and Ku Band. The design is composed of the FSS with embedded lumped resistors and Rogers RT 5880 as dielectric backed by copper based PEC layer. Rogers RT 5880 is flexible in nature and has broadband absorption properties. The upper most FSS layer of the design absorbs the incident electromagnetic (EM) wave for transverse electric (TE) and transverse magnetic (TM) polarizations. The optimized value of resistance has been set so that maximum absorption over a larger bandwidth could be achieved. Good angular stability is gained by extending operating angle upto 50°. The structure is simulated using CST software which reveals a wideband absorption response of 8.193 GHz ranging from 8.508GHz up to 16.701GHz with center frequency of 12.6045 GHz and varying value of absorptivity from 90 % to 99.98%.