VHF/UHF antenna pattern measurement with unmanned aerial vehicles

The characterization of VHF and UHF antennas is very challenging owing to the very low-operative frequency. This paper presents a novel technique (originally developed for radio-astronomical applications) that can be suitable to measure ground-based aerospace antennas in real installation conditions, with an accurate and cost-effective method which does not require additional infrastructures. The system mainly consists of a micro Unmanned Aerial Vehicle (UAV), equipped with both a RF transmitter and an antenna, properly designed to operate as a far-field artificial test-source. Experimental results on a ground-based antenna at 50 MHz are provided. The extension of this technique to characterize service antennas (telemetry, remote control) onboard aerial vehicles is also reported. A measured pattern example of a 433 MHz telemetry monopole mounted on a commercial UAV is shown.