Bbn Technologies Corporation

Raytheon Bbn Technologies Corp.

Marshall Seth Brinn

James Edwin Barger

Stephen Douglas Milligan

Richard James Mullen

Stephen D Milligan

Disclosed are systems and methods that can be used to detect shooters. The systems and methods described herein use arrival times of a shockwave, produced by a shot, at a plurality of sensors to assign weights to each of the plurality of sensors, and determine a shot trajectory based on the assigned weights.

Self calibrating shooter estimation

Systems and methods for locating the shooter of supersonic projectiles are described. The system uses at least five, preferably seven, spaced acoustic sensors. Sensor signals are detected for shockwaves and muzzle blast, wherein muzzle blast detection can be either incomplete coming from less than 4 sensor channels, or inconclusive due to lack of signal strength. Shooter range can be determined by an iterative computation and/or a genetic algorithm by minimizing a cost function that includes timing information from both shockwave and muzzle signal channels. Disambiguation is significantly improved over shockwave-only measurements.

System and method for identifying a muzzle blast using a multi-sensor total energy approach

Systems and methods for determining shooter locations with weak muzzle detection

Systems and methods for determining and disambiguating the location of the shooter of supersonic projectiles based on shockwave-only signals are described. Using several spaced sensors, an initial portion of the shockwave-only signals is sensed to determine Time-Differences-Of-Arrival (TDOA) for the sensor pairs. The resulting TDOAs are used to determine the gradient of curvature of the shockwave wavefront on the sensors. The gradient of curvature is then used to determine the disambiguated projectile trajectory.

System and method for disambiguating shooter locations

Systems and methods for compensation of sensor degradation in multi-shooter detection systems are described. In such systems, shooter position and trajectory can be estimated precisely from the shockwaves produced at the plurality of sensors by the incoming shots. However, sensor positions can shift and the performance of some sensors may degrade for various reasons. To compensate for sensor degradation that may occur over the life of a long-deployed system, the shooter estimation algorithms are dynamically adapted by performing a least-squares regression analysis of the shockwave arrival times to obtain a time residual for each shot, observing multiple shots, and weighting the individual contributions of the sensors as a function of the time residuals for the multiple shots.

Systems and method for compensation of sensor degradation in shooter detection systems

Shockwave-only solutions that estimate shooter position and shot trajectory are extremely sensitive to the quality and precision of the shock time-of-arrival (TOA) measurements as well as the accuracy to which relative sensor positions in space are known. Over the life of a long-deployed system, the sensor positions can shift and the performance of some sensors may degrade for various reasons. Such changes can degrade the performance of deployed shooter estimation systems. Disclosed are systems and methods that can be used to calibrate sensor positions based on shock and muzzle measurements processed from a series of shots fired from a known location and in a known direction, as well as an approach for dynamically adapting shock-only shooter estimation algorithms to compensate for sensor degradation and/or loss.

Self-calibrating shooter estimation

Systems and methods for locating the shooter of supersonic projectiles based on shockwave-only measurements are described. Muzzle blast signals are neither sought nor required. The system uses at least five, preferably seven, acoustic sensors that are spaced apart at least 1 meter. The sensor signals are acquired with a time resolution in the order of microseconds and processed to find and disambiguate the shockwave arrival angle unit vector. Two different Time-Difference-Of-Arrival (TDOA) measurement techniques are described, with one technique using counters in each signal channel and the other technique using cross-correlation between signal channels. A genetic algorithm can be used to efficiently disambiguate the results.

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Newton, MA, United States of America

Marshall Seth Brinn