The increasing use of Unmanned Aerial Vehicles (UAVs) poses significant challenges to airspace control and the protection of critical infrastructure. In scenarios where optical and radar-based systems are limited or impractical, passive acoustic sensing presents a reliable alternative for UAV detection and localization. This paper presents a system for acoustic UAV detection and direction-of-arrival estimation, based on a hemispherical microphone array. The array’s geometry enables omnidirectional localization while resolving elevation ambiguities typically encountered in planar microphone configurations. A signal processing pipeline is developed to detect and track UAVs across a range of environmental conditions. Experimental flight tests with UAVs of various sizes are conducted to assess the system’s performance in realistic scenarios. Representative tracking results from these tests are presented to demonstrate the applicability of the approach. The system offers potential for applications in surveillance, situational awareness, and the protection of critical infrastructure by enabling accurate passive directional localization of aerial sound sources.
Ernst et al. (2025) studied this question.