Design Of Acoustic Localization System Of Supersonic Bullet

Sniper is good for concealment, independence and flexibility, thus it has become one of the most severe threats to soldiers in urban warfare. To find the enemy’s snipers in time is of great significance for protecting our soldiers.The localization technology based on acoustic method has the characteristics of low power consumption, high availability and easy to realize miniaturization. Hence, it has wide application in the sniper detection and localization systems. In this paper, we research the acoustic localization method based on TDOA.The bullet of modern sniper rifle travels at supersonic speeds; it generates a "N" shape wave in its surrounding air. And a muzzle blast produced when the bullet is fired. In this paper, we research the localization method based on the two kinds of acoustic waves. In order to estimate the TDOA of the muzzle blast and the "N" shape wave, we propose the TDOA estimation algorithm of muzzle blast based on cross-correlation and the TDOA estimation algorithm of "N" shape wave base on analog signal processor.The hardware circuit of the localization system is controlled by16-bit ultralow power consumption microcontroller MSP430x5xx. In this paper, we design and implement the store function of localization records based on FLASH. In order to display the localization information and set the system, we design and implement the keyboard and LCD display module. The localization information is displayed in a positioning dial. And the user of the localization system can check the previous records. The module of real time clock is designed and implemented to provide the calendar information for the system. For the purpose of improving the accuracy of localization, we design and implement the module of temperature sensor. The measured temperature is used for the compensation of the sound velocity.At the last of the paper, the simulation results of the proposed TDOA estimation algorithm of the muzzle blast and the "N" shape wave are presented. The simulation results show that the two algorithms can estimate the TDOA rightly with good precision.