Design of Double Layer Frequency Selective Surface with Almost Flat Pass Band and Sharp Roll Off

摘要

This paper presents aperture type frequency selective surface (FSS) with tripole and annular ring shaped element. Different designs are investigated to accomplish sharp roll off, flat band, polarization and incident angle independent frequency response. Finally annular ring FSS exhibits sharp roll off (maximum 27 dB/GHz), almost flat response, polarization (at 0° and 90°) and incident angle independent characteristic. The designs are scaled to achieve predetermined pass band frequency. Simulated results are verified by measured data. Final structure shows nearly-flat band pass property from 3 GHz to 4 GHz. Practical measurements are done by standard microwave test bench. The simulated and measured results are in good parity.