Testing of 30-GHz low noise receivers

NASA-Lewis sponsored studies of tree growth in conlnuniCations traffic have indicated that the frequency spectrum allocatea to fixed-service satellites at the C ana Ku bands will reach saturation uy the early 1990's. The next nigher frequency Dands allocated fo r coinnunications satellites are el., to 30 GHz for the uplink and 11.1 to eU.e GHz for the downlink. Current plans for oevelupiny satellite systems that use these bands i tic Iuoe a NASA demonstration satellite (ALTS). Une of tilt Loin ponents identified as critical to the SuCCt,s of that mission is a 21.5 to 30 GHz satellite receiver. in response to that identification, NASA has sponsored the development of such a receiver to ore prouf-of-concept (PUC) level. Design and faoricatlon of such POC model receivers was carried out under parallel contracts awarded to LNR CuumiunlCdtions, Inc. of Hauppauye, New York and to ITT Defense Loianunications Division of Nutley, New Jersey. Tne most significant of the performance goals were a 5 dB maximum noise figure, a 2.o uHz passoand, and 20 dB RF to IF gain. Following delivery of naroware from each of the cuntrdCtors, an in-house test program was undertaken at NASA Lewis in order to verify the ^_ontrdctor-reported performance and to provide a cumparison of the two receivers under identical test conditions. The present paper reports the results of those tests.