Acoustic Signature Analysis for Localization Estimation of Unmanned Aerial Vehicles Using Few Number of Microphones

¹ LAUM - UMR 6613, Avenue Olivier Messiaen, 72085, Le Mans, France
² ENSIM, 1 rue Aristote, 72000 Le Mans, France

^* e-mail: torea.blanchard@hotmail.fr
^** e-mail: jean-hugh.thomas@univ-lemans.fr
^*** e-mail: kosai.raoof@univ-lemans.fr

Abstract

In recent years, the current technological improvements of Unmanned Aerial Vehicles (UAV) have allowed more and more efficient use for applications ranging from simple amateur shooting to more professional tasks. Being handy, drones can easily fly near sensitive sites, such as power plants, airports or ministries. It is therefore necessary to develop systems able to keep watch such sites. However, the size and the composition of these devices make optical or electromagnetic systems inefficient for their detection. This study proposes an alternative exploiting the sound wave emitted by their motorization and / or their aerodynamic whistling. For this, an acoustic antenna with few microphones was sized to be sensitive to frequencies emitted by a drone. Firstly, an experimental analysis on the noise made by a drone was carried out. The results allowed us to settle the geometry of the antenna in order to process localization. Two methods of location are used. The first is based on an energy approach providing the acoustic field reconstruction in all directions of space. The second estimates the position of the source by inverting a system exploiting the arrival time differences of the acoustic wave between different pairs of microphones. Numerical simulations, supported by a measurement campaign, make it possible to highlight the performance of the methods used.