Design and Analysis of mobile microphone arrays for acoustic drone tracking

The growing security threat posed by hostile drones (UAVs) highlights the urgent need for effective detection systems. Besides optical, radar or radio frequency systems, the acoustic domain offers significant but underutilized capabilities. Since human hearing is inherently limited in detecting and localizing weak or high-frequency sounds in noisy or dynamic environments, microphone arrays represent a significant improvement in tracking drone noise. In the literature, most of the existing acoustic systems are stationary and focus on the detection or localization of individual drones. The integration of mobile microphone arrays on vehicle roofs or soldier helmets can enhance military capabilities by enabling real-time tracking of drones in diverse and challenging scenarios. In this paper, we present the design criteria and development of a practical microphone array system capable of detecting and tracking multiple drones. First, we describe the implementation of a hemispherical array of 32 microphones. Then, we consider possible adaptations, e.g. in terms of reducing the number of microphones by selecting subarrays to address low-power consumption considerations and real-time processing for sound source localization. Finally, we show experimental results of a dataset recorded in a fixed and mobile scenario where the microphone array was mounted on a vehicle roof.