volume | PIER Journals

Abstract

This paper presents a concept of a broadband absorptive EMI shield based on a multilayer of seawater and transformation dielectrics. The shield structure consists of one seawater layer and four matching layers, which function for EMI energy dissipation and wave impedance matching. The thickness and dielectric constant of the four matching layers are optimized by a genetic algorithm (GA) for a prescribed frequency band. To reduce the total thickness of the absorptive shield structure, the four matching layers are squeezed in the vertical direction using the method of transformation optics. Finally, a numerical prototype of an absorptive EMI shield is synthesized in the frequency band 0.5-1.5 GHz using a frequency-domain solver.

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Dr. Bi-Ying Chen

Dr. Shen-Yun Wang