Sensitivity of shot detection and localization to environmental propagation

Abstract

Acoustic sensing systems are used to detect and localize mortar and small arm shots on the battlefield. This study is an experimental investigation on the sensitivity of the sensing performance to environmental propagation. For simulated mortar shots, the muzzle wave detection range is observed to vary by a factor of three from day to day and with the propagation direction, due to the varying atmospheric refraction. For small-arm fire shots, the shot azimuth is estimated by some degrees in an open environment, but large errors are observed for shots nearby a forest (with Mach wave reflections) in adverse atmospheric conditions. Last, the shooter’s range estimate is found to feature bias and scatter. Atmospheric turbulence is found to cause the observed shot-to-shot variability of the Mach wave characteristics, which drives the scatter in range estimate. The study promotes a careful assessment of impulse sound propagation effects when analyzing, developing, evaluating and using systems for shot detection and localization.