The Submillimeter Array (SMA) requires precise full-sky blind pointing for its eight 6m antennas, aiming for an error within 3′′, a fraction of the 34′′ FWHM beam at 345 GHz. SMA’s typical 2–3′′ rms pointing accuracy is crucial for efficient array operation, especially with 4 to 6 antenna relocations across 23 pads in various configurations each semester. Traditional calibration using optical guidescopes for mount model errors has shifted to interferometric pointing measurements on quasars, for full model acquisition and baseline calibration. Following every array reconfiguration, mechanical imperfections in antenna mounting lead to significant deviations in azimuth encoder offset and axis tilt parameters, complicating pointing accuracy. To overcome this, a three-layer feed-forward neural network, trained on over ten years of data for each antenna-pad configuration, predicts post-reconfiguration changes. This approach, currently under evaluation and refinement, aims to expedite re-calibration, indicating potential substantial reductions in calibration time and enhanced operational efficiency.
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