Calibration and performance measurements of the NASA Deep Space Network antennas upgrade for Ka-band (26-GHz)

The National Aeronautics and Space Administration (NASA), Deep Space Network (DSN) has recently installed equipment to support high-data-rate missions (within 2 million kilometers of Earth) with simultaneous S-band uplink, S-band downlink and Ka-band (26-GHz) downlink. The S-band links are required for traditional TT&C support to the spacecraft, while the Ka-band link is intended for high-data-rate science returns. The new Ka-band system combines the use of proven DSN cryogenic designs, for low noise system temperature, and high data rate capability using commercial telemetry receivers. The initial support is required for the James Webb Space Telescope (JWST) in 2013 and possibly other missions. The upgrade has been implemented into 3 different 34-meter Beam Waveguide (BWG) antennas in the DSN, one at each of the DSN complexes which are located in Canberra (Australia), Goldstone (California) and Madrid (Spain). After the completion of these upgrades, a comprehensive campaign of tests and measurements took place to calibrate these antennas for optimum performance at 26-GHz. This paper describes these measurements and presents the performance of the 34-m BWG antennas subnet.