Ultra-Long Distance Explosive Source Localization Based on Characteristics of IMS Acoustic Signal

The hydroacoustic network of the International Monitoring System (IMS) is designed to monitor the world’s oceans to detect signals that might originate from any underwater nuclear test. To analyze the abilities of detection and parameters estimation of IMS hydrophone stations, an ultra-long distance explosive experiment was deployed in the Western Pacific. These underwater explosions deployed by the Institute of Acoustics with energy yields equivalent to 1 kilogram of TNT were detected at hydrophones HA11, which consists of two triplets at the north and south of Wake Island. Explosive signals are used to characterize and locate the explosions. The effect of the bathymetry on azimuth estimation in the deep sound channel at distances up to thousands of kilometers is discussed. A joint localization method that combines the propagation times and back-azimuths is applied to get the latitude and longitude of the explosions. The experimental results suggest that the azimuth estimation error is less than 0.5° and the joint localization method can improve the accuracy of locating the explosions.