Acoustic direction finding using multi-dimensional Fourier transform

In this paper we present a Acoustic Direction Finding (ADF) method that employs multi-dimensional Fourier transform to find both, azimuth and elevation angle of a source that generates sound wave. The proposed solution is basically a three-dimensional extension of the well known two-dimensional DFT-based algorithm where elevation angle is computed for only one hemisphere. There is a number of applications where it is enough but here we mean a device that is to be used for finding small objects (drones) that can fly above as well as beneath the point of installation of the device. Therefore the elevation must be determined correctly for the whole sphere. The results of computer simulations have been presented to show the ability of the proposed algorithm to solve the problem of simultaneous estimation of DOA of acoustic wave for a number of sources in a whole sphere. The advantages and disadvantages of the proposed solution were pointed out, as well as possible and necessary improvements.