Bae Systems Information and Electronic Systems Integration Inc.

Tyler Robinson

Peter Dusaitis

John J Kelly

Joseph Warner

Greg M Fehling

Milton Janosky

A system and method for estimating the geographic location of an RF emitter which involves spatially filtering and receiving RF signals through use of a beamforming antenna array having multiple overlapping beams; detecting and measuring the time-of-arrival and amplitude of signals which are received in each beam through use of multiple synchronized receivers; identifying simultaneous detections of the same emitter which have occurred in adjacent beams; projecting the associated beamformed antenna gain patterns onto the underlying terrain for all instances in which there was a simultaneous detection in adjacent beams; weighting and accumulating all projections to form a Maximum Likelihood Surface (MLS); and finally, estimating the location of the emitter through analysis of the resulting MLS.

Gain projection geo-location systems and methods

Techniques are disclosed for detecting, identifying, and/or geolocating RF communications devices, such as FRS radios, high-power cordless phones, cellular phones, and other wireless communications receiver devices. The techniques exploit a vulnerability present in such devices, and can be used to detect (e.g., up to 300 meters) and geolocate (e.g., within +/&#x2212;3 meters) those devices. The vulnerability is that receiver circuitry of the target devices emanate RF mixing products when flooded with RF energy or suitable stimulus signal. Such a response to a stimulus signal is unexpected or otherwise unintentional, as receiver circuitry is generally not designed to transmit information. The RF frequency, phase, and amplitude of these sideband RF responses can be used to detect and location the devices. The techniques work in the presence of interference, and can be used on devices that are powered on or off.

Locationing of communication devices

Techniques are disclosed that allow for the detection, identification, direction finding, and geolocation of wireless emitters in a given multipath environment. For example, the techniques can be used to detect and identify a line of bearing (LOB) to an IEEE 802.11 emitter in a building or in an open field or along a roadside. Multiple LOBs computed from different geographic locations can be used to geolocate the target emitter. The techniques can be embodied, for instance, in a vehicle-based device that can survey the target environment, detect an IEEE 802.11 emitter and identify it by MAC address, and then determine various LOBs to that emitter to geolocate the emitter. In some cases, a sample array of response data from the target emitter is correlated to a plurality of calibrated arrays having known azimuths to determine the LOB to the target emitter.

Direction finding and geolocation of wireless devices

Techniques are disclosed that allow for the detection, identification, and direction finding of wireless emitters in a given multipath environment. For example, the techniques can be used to detect and identify a line of bearing (LOB) to an IEEE 802.11 emitter in a building or in an open field or along a roadside. In some cases, multiple LOBs can be used to geolocate the target emitter if so desired. The techniques can be embodied, for instance, in a handheld device that can survey the target environment, detect an IEEE 802.11 emitter and identify it by MAC address, and then precisely determine the LOB to that emitter. In some cases, a sample array of response data from the target emitter is correlated to a plurality of calibrated arrays having known azimuths to determine the LOB to the target emitter.

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Merrimack, NH, United States of America

Tyler Robinson