Flight path tracking and acoustic signature separation of swarm quadcopter drones using microphone array measurements

Flight paths and individual acoustic signatures of up to four simultaneously flying quadcopter drones are calculated from measurements with a 64-channel microphone array. The data processing consists of two steps. First, a frequency-domain beamforming method is used to reconstruct the individual flight trajectories. The separation of the sound signals from the drones is accomplished in a second step using a moving-focus time-domain beamforming method.

The accuracy of the flight paths calculated from the array measurements is evaluated by comparing them to paths reconstructed from additional synchronous camera recordings. The quality of the separated acoustic signatures is assessed via reference measurements of a single drone of the same type.