Low-Loss Miniaturized FSS for Quasi-Optical Feed System of Atmospheric Remote Sensing

This paper introduces a novel Frequency Selective Surface (FSS) for TE and TM polarizations in the quasi-optical feed system of atmospheric remote sensing. The multi-channels are divided into two groups corresponding to the demand: three bands centered at 23.8 GHz, 31.4 GHz, and 54 GHz are reflected, while the remaining bands around 89 GHz and 118.75 GHz are transmitted in low insertion loss. Subsequently, the insensitivity of the incidence angles is demonstrated. The ripples caused by the reflection among layers deteriorate as the angle arrives at 45°. The worst insertion loss is no more than 0.75 dB. This design is desirable for the quasi-optical feed system, which can spectrally separate the incident waves for microwave sounder instruments.