Low Noise Microwave Receiving Systems on a 64 m Antenna

The performance capability at S-, X- and K-band of the NASA/JPL 64 m Cassegrain antenna at Goldstone, California, is reviewed. The multiple feed system allows X-and K-band atmospheric research studies to be conducted simultaneously with mission directed S-band spacecraft tracking. A description of the antenna system and its multiple operation is followed by gain and efficiency comparisons at the three frequencies . The total operating system temperature, and its frequency dependence, is presented and discussed. Antenna gain and efficiency, and zenith system operating temperature are summarized, at S- and X-band respectively, by 62 dB, 63%, 16K; and 72 dB, 52%, 24K. Preliminary measurements for K-band are 76 dB, 39%, 29K.