Passive Radar detection of small UAV over sea

During a trial over the Trondheim-fjord in Norway fall 2018, aDVB-T based passive radar system was used for detecting a small unmanned aerial vehicle (UAV) over sea. The measurements show a possible detection range of 1 km radial range away from the radar receiver and with terrain masking of the direct signal interference from the transmitter to the receiver. Strong multipath from the sea match well with simulations. The multipath will, with a single receiver channel, severely affect the radar performance, but this could for shorter detection distances be mitigated by using two to three receiver channels at differing altitude, with the benefit of an additional gain of up to 6dB caused by the multipath.