Characterization of the Murchison Widefield Array Dipole with a UAV-mounted Test Source

Aperture arrays such as the Australian Murchison Widefield Array (MWA) represent the modern approach to low frequency radio astronomy. The presence of mismatched front-end amplifiers and mutual coupling between the array elements produce distortions in the embedded-element patterns. Advanced techniques are therefore required to perform the in-situ validation and instrumental calibration. Unmanned Aerial Vehicles (UAVs) technology provides suitable tools to accomplish these tasks. In preparation of possible UAV applications at the MWA site, some tests have been carried out in Italy on a subarray of MWA dipoles. This contribution presents the results of the measurement session with particular reference to the calibration of the measurement equipment.

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