The Bullet Shockwave-Based Real-Time Sniper Sound Source Localization

摘要

Real-time sniper sound source localization in a real environment has long been an important research topic in the acoustic field. All those positioning systems utilize the Muzzle Blast signal for positioning. Acquiring a low signal to noise ratio Muzzle Blast signal is the most effected issue in the unfavorable situations. Detecting the Shockwave signal in the real environment is easier due to its higher signal to noise ratio value and some other its specific features. This paper focuses on the designing of a system that deals with the sniper positioning based on using only bullet Shockwave signals. The first acquired Shockwave signal in the microphones' array is not from the fired bullet and specifies only the relevant point on the bullet trajectory. Hence, in this research, by utilizing the two least microphones count arrays in the 2-Dimensional real environment, first it is obtained the bullet trajectory, and then in an initiative, the reduction curve of the Mach number on this bullet trajectory, is devoted to locating the source of the fire. Also, the generalized cross-correlation phase transform method is used for calculating of the time delays between the microphones in an array. Based on the proposed method, the experimental results demonstrate the sniper locating with a precision of less than 30 meter at the distance of 400 meter, using an AK_47 weapon and a 6.72 millimeter caliber in different real environmental situations.