Broadband absorber of impedance dispersion lossy patterned resistive films

Abstract

Impedance characteristics and frequency dispersion of typical lossy patterned resistive films are extensively investigated. On this basis we put forward an improved circuit-pattern direct extraction method (CPDEM) for a patterned lossy resistive film based broadband absorber design. The pattern parameters are directly extracted from the numerically calculated circuit model and further optimized to meet the design requirements. Herein, two broadband designs are demonstrated, whose relative bandwidth is 127% with a thickness of 0.086 lambda(L) at the lowest operating frequency of the absorption band and 178% with a thickness of 0.102 lambda(L). Our numerical calculation and full-wave electromagnetic simulation are in good agreement with the experimental results, which proves that this design method is feasible and accurate. This CPDEM might also provide a guideline for the design of a resistive film absorber.