Direction Of Arrival Estimation using Microphone Array

Abstract

Human beings can tell the direction of sound by utilising both their ears. They may instinctively determine the di-rection of sound by combining the somewhat varied impulses that arrive at our ears. Similarly, an array of microphones connected to a computer may be used to create a sound localisation system. The basic idea behind utilising microphone arrays to estimate Direction Of Arrival (DOA) is to leverage phase information in signals picked up by spatially separated sensors (microphones). The acoustic signals arrive to the microphones with temporal delays when they are spatially distant. These time-delays are determined by the signal's DOA for a known array geometry. The audio signal is recorded using a miniDSP UMA-16 microphone array with plug and play USB audio connection. For linear arrays, the angle between the array's orientation and the sound source is calculated here. Given that the sound signal arrives at each microphone at various times, corresponding to different propagation paths, it's reasonable to infer that the recorded signals in each microphone have a Time Difference Of Arrival (TDOA), which is an important factor in microphone array processing. With the aid of the UMA16 microphone array, more visible and accurate sound source localization was achievable at lower sound power intensities, which was considered to be a significant innovation in the field of sound source localization. In addition, the DOA was calculated using an SVM classifier, which can categorise audio signals in coarse as left, right or front, and the performance metrics including accuracy, specificity and sensitivity are analysed.