Design of a helmet-mounted microphone array for sound localization

This paper presents a part of a microphone based system installed on a soldier's helmet for the application of localizing a sniper/insurgent attack in the battle space environment to increase situational awareness of the foot soldiers. More specifically, the main focus of the paper is to develop a computational method to determine the optimum number of microphone sensors and their optimum positions on the helmet. The relative location of the source with respect to the sensors causes some sensors to not be in the-line-of-sight therefore it is proposed that a) for an accurate localization, estimation of time delay of arrival to be accommodated with diffraction path/length, and b) intensity difference between microphone pairs to be employed for making an initial guess of the source location. The results of this study showed that utilizing the diffraction path enhances the localization performance and the intensity difference results in fast and low computational cost convergence of the iterative algorithm.