Abstract: A system and method for detecting the trajectory of a projectile is presented. One system includes a flash detection sensor, an acoustic sensor, an optical sensor and a processor logic mounted on a vehicle. The flash detection sensor detects a flash of a projectile being launched. The acoustic sensor detects when a blast wave associated with the firing of the projectile reaches the vehicle. The optical sensor takes two or more images of the same projectile. The images are typically not in the visible light spectrum. The processor logic calculates a trajectory of the projectile based on the images and data collected by the acoustic sensor associated with the blast wave. The processor logic may generate a warning signal to warn an operator of the vehicle about the projectile.

Abstract: Techniques are disclosed for determining the bearing from a three-axis geophone to a seismic source, such as a person or other man-made seismic source. In one embodiment, the techniques are implemented as a method that includes receiving outputs from a three-axis geophone (x axis, y axis and z axis outputs), computing a magnitude signal based on the x and y axis outputs, determining locations of each local peak in the magnitude signal, computing a bearing estimate for each peak, and computing a median of the bearing estimates. The resulting median bearing is an estimate of the bearing from the geophone to a target seismic source. In one such case, computing the magnitude signal based on the x and y axis outputs is performed in response to detecting the target seismic source in the phase-shifted z axis output.

Abstract: A system for detecting of the location of shooters with respect to a moving platform is disclosed and claimed. The system makes use of the ballistic shock of ordnance to find a shooter by one of three methods: using a single small array (that detects ordnance shock) in conjunction with the electro-optic infrared detection of the shot; using a single small array that detects both the muzzle blast (often obscured on an aircraft in flight) and ordnance shock (that is more easily detected above the background noise); and using multiple small arrays, each of which detects ordnance shock, to triangulate the ordnance trajectory.

Abstract: Techniques are disclosed for determining the bearing from a three-axis geophone to a seismic source, such as a person or other man-made seismic source. In one embodiment, the techniques are implemented as a method that includes receiving outputs from a three-axis geophone (x axis, y axis and z axis outputs), computing a magnitude signal based on the x and y axis outputs, determining locations of each local peak in the magnitude signal, computing a bearing estimate for each peak, and computing a median of the bearing estimates. The resulting median bearing is an estimate of the bearing from the geophone to a target seismic source. In one such case, computing the magnitude signal based on the x and y axis outputs is performed in response to detecting the target seismic source in the phase-shifted z axis output.

Abstract: A robust, easily deployable, covert, passive intrusion detection system uses one or more E-field sensors to detect the presence of a moving individual and to provide an indication of the presence of the individual adjacent the sensor based on E-field distortion produced by the individual. Single-ended and differential E-field sensors with noise canceling and a guarding circuit provide sufficient sensitivity, with filtering from 0.5 Hz to 8.0 Hz selecting only human intruders. Either visible or invisible flashing light sources at the sensor indicate the presence of a moving individual at the sensor, thus to provide intruder location without the necessity of providing a geolocation system.

Abstract: A system is provided for determining the type of vehicle which has never been sensed before that is transiting between a cluster of acoustic and seismic sensors by graphing an acoustic source level against a seismic source level for the vehicle, with light vehicles such as pick-up trucks being distinguished from heavy tracked vehicles such as tanks by where on the graph the plotted point for a vehicle lies.

Abstract: A resonator as disclosed that has a plurality of resonating chambers having a predetermined size that attenuate sound in a conduit. The resonator may be disposed along the inner periphery of the conduit. Alternatively, it may be disposed on the outside periphery of the conduit so that flow through the conduit may be unrestricted. Additionally, the resonator may include a honeycomb fairing to attenuate sound at higher frequencies. Also disclosed is a system in which a resonator may be located within the conduit of an HVAC system to attenuate the sound.