Title :
The new ultra low noise diplexed X-band microwave feed for NASA 70-m antennas
Author_Institution :
Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA
Abstract :
This paper describes the configuration, detail design, and performance of a new ultra low noise diplexed X-band microwave feed system, called X/X diplexing feed, for the Deep Space Network 70-m antennas. In this microwave feed, the uplink signal is combined with the downlink signal in a diplexing junction placed near the input of a wide-band feedhorn. This configuration allows the majority of the components in the downlink path to be placed in a cryogenically cooled container, resulting in a drastic reduction in the loss (noise temperature) of the feed. Combined with low noise HEMT amplifiers, this feed provides the lowest noise diplexed feed in the DSN. The total noise temperature of the 70-m antennas with this feed is estimated to be 16.1 K
Keywords :
antenna feeds; horn antennas; microwave antennas; multiplexing equipment; satellite antennas; 70 m; Deep Space Network antennas; X/X diplexing feed; cryogenically cooled container; dichroic mirror; diplexing junction; downlink signal; low-noise HEMT amplifiers; ultralow noise diplexed X-band microwave feed; uplink signal; wide-band feedhorn; Antenna feeds; Broadband amplifiers; Containers; Downlink; HEMTs; Microwave antennas; NASA; Noise reduction; Temperature; Wideband;
Conference_Titel :
Aerospace Conference Proceedings, 2000 IEEE
Conference_Location :
Big Sky, MT
Print_ISBN :
0-7803-5846-5
DOI :
10.1109/AERO.2000.878474
