Antenna Position Estimation Results from In-Situ Measurement Data

In this paper, legacy data from an in-situ measurement campaign that was performed on a compact sub-array of Low Band Antennas (LBAs) of the LOFAR radio telescopes are used to illustrate the effectiveness of a recently developed antenna element position estimation method. The method allows recovery from aliasing after sub-sampling of odd harmonic signals transmitted from an Unmanned Aerial Vehicle (UAV) with a known position in the sky. This allows not just small errors due to element placement deviations from the designed positions to be detected, but also large errors due to the incorrect connection of antenna elements to the digital back-end, or malfunction of receiver amplifiers. The results look promising and can be improved by using an increased number of samples from a suitable UAV flight path, and by updating the data model to include calculation of the phase errors from the analog receiver signal paths.