Electromagnetic characterization of installed antennas through UAVs

The characterization of the radiation pattern of low-frequency antennas is a challenging problem that requires an advanced strategy to reach the expected measurement accuracy. A micro Unmanned Aerial Vehicle (UAV) has been used as a radio frequency test-source to perform such measurements with an innovative technique, obtaining outstanding results. In particular, a Differential Global Navigation Satellite System (DGNSS) based positioning has been introduced through the use of an external GNSS (Global Navigation Satellite System) receiver to obtain the UAV position during the flight with a high level of accuracy. The system has been experimentally tested since a challenging topic is to define all the issues that can occur in the combined use of unmanned aerial systems and electromagnetic components. For this reason, it was investigated to assess sensors problems (such as interferences and positioning troubles with the external sensor) and to define some best practices in the use of such system for this particular field of application to reach the expected result. Finally, an experimental case to demonstrate the suitability of the proposed system is presented in this paper. The radiation pattern of a log-periodic antenna at 250 MHz has been measured with good results.