Propagation characteristics at 20 GHz for satellite communications

Propagation characteristics were investigated by gathering data with a very small aperture terminal (VSAT) which received a 20-GHz signal from the Olympus satellite. The experimental arrangement is described. The weather was drier than usual, and fewer events were observed than expected. Typical events for Olympus show attenuation of the horizontally received signal, which was at 19.77373 GHz. The equipment was carefully calibrated during clear weather. Several fade events observed are described. The disappearance of Olympus from the end of May 1991 until its recovery in mid-August 1991 was a setbacks; however, observing another satellite helped in utilizing the equipment effectively to measure attenuation at 20 GHz. The maximum fade rate observed so far was 1.5 dB/s