Optimization-Driven design of a 2-bit coding based metasurface absorber for enhanced EMI shielding and RCS reduction

Abstract

In this paper, a 2-bit optimized coding based metasurface absorber (CMA) is designed for electromagnetic interference (EMI) shielding and radar cross section (RCS) reduction. The 2-bit CMA comprises four digital elements using triple circular ring resonators to represent ‘00′, ‘01′, ‘10′ and ‘11′, through optimized coding sequences obtained via particle swarm optimization (PSO) algorithm applied to array theory. The simulation results demonstrate that optimized pattern performs better, achieving an RCS reduction exceeding −10 dB across 7.5 to 17.5 GHz frequency range, with additional evidence from 3D scattering patterns at 9.76, 11.90, 13.84, and 16.80 GHz confirming its remarkable ability to suppress bistatic RCS. The optimized pattern also demonstrates high shielding effectiveness with near unity absorption. A prototype is fabricated and experimentally tested to validate the optimized pattern performance, with both simulation and experimental results confirming the optimized pattern as a viable option for achieving enhanced EMI shielding and RCS reduction.