The Study of Acoustic Source Localization Using a Small Microphone Array for Condition Mornitoring

The aim of this research is to investigate microphone array techniques based condition monitoring (CM). In this paper, a cost effective microphone array configured with 4-sensors and data acquisition systems is investigated theoretically and experimentally to evaluate its performance in characterising sound sources in different acoustic environments. Time delay estimation (TDE) is used as a basic tool for calculating the time delay of the sound source arrived at each of the 4-sensors and hence the localization parameters of the sound source such as azimuth, elevation and distance can be calculated from the TDE information. Results are presented for experimental studies both in a semianechoic chamber, an outdoor environment and an enclosure. Comparing the results obtained under different conditions, it has confirmed that the microphone array system can catch the location of the main sound source and also has ability to track and give the azimuthal trajectory of a moving target with high degree of accuracy.