James W. Lamb, David P. Woody [1]
October 23, 1998
Keywords:
One of the OVRO antennas has been instrumented with 48 thermistors on the backing structure, and the data taken over a period of more than a month with a 2 min time resolution have been analyzed. The nighttime temperature is uniform within ~2 C while temperature differences across the structure of up to 12 C are observed during the day. There is a strong inverse correlation between wind speed and temperature variance and a weaker one on the direction of the sun and wind relative to the antenna pointing direction. Structural modeling shows that pointing and focus are strongly affected, but the effect on surface rms is at the level of 10 m. By using the temperature information to correct the pointing and focus in real time should be possible to effect a significant improvement in performance of the antennas.
[1] OVRO
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Last modified: 09 December, 1999
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