EVLA Memo 103 Performance Tests of the EVLA K- and Q-Band Systems
نویسندگان
چکیده
Sensitivity measurements performed on EVLA antenna #14 show that the cold-sky zenith system temperature is about 45K for the 18 – 26 GHz band, and 60 K for the low frequency end of the 40 – 50 GHz band, rising to 95 K at the high frequency end. Efficiency measurements based on the planet Venus show the antenna efficiency to be about 50% in the 18 – 26 GHz band, and about 28% for the 40 – 50 GHz band. The 18 – 26 GHz band performance easily meets EVLA requirements. The 40 – 50 GHz band requirements are met for system temperature, but the observed efficiency falls short of the required value of 34%. We expect to meet this requirement after implementation of better focusing, pointing, and a final round of holography.
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EVLA Memo 137 Performance Tests of the EVLA K, Ka, and Q-Band Receivers
Efficiency observations performed in January and February 2009 during clear dry weather with the EVLA receivers mounted on antenna #24 show excellent performance at K, Ka, and Q bands. System temperatures are well below project requirements, with mid-band values of 37, 43, and 58 K at K, Ka, and Q bands, respectively. Antenna efficiencies decline smoothly with increasing frequency, from a high ...
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