Near-Field Phase Reconstruction for UAV-based Antenna Measurements

A non-tethered Unmanned Aerial Vehicle equipped with a RF source has been used as a near-field scanner in the VHF band. In this configuration, the source is not phaselocked to the receiver local oscillator/clock. A reference antenna, placed at a proper distance from the antenna-under-test, has thus been exploited to reconstruct the phase. Experimental results at 175 MHz for the central element of the Pre Aperture Array Verification System of the Square Kilometre Array are shown. The comparison with simulations shows very good agreement.