165/183 GHz FSS for the MetOp second generation microwave sounder instrument

This paper reports the design of a Frequency Selective Surface (FSS) which simultaneously allows transmission of 175.3 - 191.3 GHz radiation and rejection from 164 - 167 GHz with a loss <;0.5 dB for TE wave polarization at 45° incidence. The state-of-the art filter consists of three air spaced perforated screens with unit cells that are composed of nested resonant slots. The FSS satisfies the stringent electromagnetic performance requirements for signal demultiplexing in the quasi-optical feed train of the Microwave Sounder (MWS) instrument which is under development for the MetOp-SG mission.