Modulating Features of Field Measurements with a UAV at Millimeter Wave Frequencies

This contribution discusses time-variant propagation channels and corresponding mechanisms that can induce amplitude and frequency modulation. Especially in the context of rotating wind turbines, that may disturb the modulated content of navigation signals, this is a relevant question. In particular, this is a timely topic in Germany where a huge amount of wind power investments are blocked due to assumed incompatibilities between avionic navigation systems and rotating wind turbines. As a typical communication channel UKW radio can be considered as well. Fundamental considerations are made by simulations with respect to the classification of a propagation channel as quasi-static or dynamic. Furthermore, first results are presented on channel measurements with a moving receiver mounted on a UAV flying platform. For such scenarios it is investigated how the motion of the receiver and the frequency stability may influence the actual measurement quantity of a time varying propagation channel.