Speech enhancement using a microphone array mounted on an unmanned aerial vehicle

An attempt to record speech signals using an array of directional microphones carried by an unmanned aerial vehicle (UAV) is reported. The speech enhancement algorithm estimates the power spectral densities (PSD) of the target speech and rotor noise which are used to calculate a Wiener filter for extracting the target speech. The calculated Wiener filter is then applied to the output of a beamforming implemented on the microphone array signals. The proposed algorithm was tested on a prototype UAV equipped with directional microphones each of which was orientated in different directions. The experimental results revealed that the proposed method was able to significantly reduce both the UAVs rotor noise and an interfering speech in a recording.