A 20/30 GHz Reflectarray Backed by FSS for Shared Aperture Ku/Ka-Band Satellite Communication Antennas

This letter presents a dual-polarized and dual-frequency reflectarray backed by a frequency selective surface (FSS) with application to shared aperture Ku/Ka-band satellite communication antennas. The reflectarray has been designed to operate simultaneously at 20 and 30 GHz (downlink and uplink frequencies in Ka-band) using a single-layer configuration, where the printed elements are etched on the upper substrate of a two-layer triband FSS. The FSS has been designed to be transmissive at 12 GHz (downlink frequency in Ku-band) and reflective at 20 and 30 GHz. An 18 × 18-cm
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prototype has been fabricated and tested, showing a good matching with the simulations. The measured gains are 28.5 dBi at 20 GHz and 32.25 dBi at 30 GHz.