Precision and accuracy of acoustic gunshot location in an urban environment

Robert B. Calhoun; Clark Dunson; Murphey L. Johnson; Scott R. Lamkin; William R. Lewis; Robert L. Showen; Mark A. Sompel; Lester P. Wollman

arXiv · 2108.07377

Precision and accuracy of acoustic gunshot location in an urban environment

Robert B. Calhoun·Clark Dunson·Murphey L. Johnson·Scott R. Lamkin·William R. Lewis·Robert L. Showen·Mark A. Sompel·Lester P. Wollman

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Abstract

The muzzle blast caused by the discharge of a firearm generates a loud, impulsive sound that propagates away from the shooter in all directions. The location of the source can be computed from time-of-arrival measurements of the muzzle blast on multiple acoustic sensors at known locations, a technique known as multilateration. The multilateration problem is considerably simplified by assuming straight-line propagation in a homogeneous medium, a model for which there are multiple published solutions. Live-fire tests of the ShotSpotter gunshot location system in Pittsburgh, PA were analyzed off-line under several algorithms and geometric constraints to evaluate the accuracy of acoustic multilateration in a forensic context. Best results were obtained using the algorithm due to Mathias, Leonari and Galati under a two-dimensional geometric constraint. Multilateration on random subsets of the participating sensor array show that 96% of shots can be located to an accuracy of 15 m or better when six or more sensors participate in the solution.

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BibTeX RIS

Robert B. Calhoun, Clark Dunson, Murphey L. Johnson, Scott R. Lamkin, William R. Lewis, Robert L. Showen, Mark A. Sompel, Lester P. Wollman. 2021-08-16. Precision and accuracy of acoustic gunshot location in an urban environment. https://arxiv.org/abs/2108.07377

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