Ultrasound sensor for remote imaging of concealed weapons

A breadboard ultrasound sensor was developed for remotely detecting and imaging concealed weapons. The breadboard sensor can detect metallic and non-metallic weapons concealed on a human body under heavy clothing at ranges up to 8 m and image the concealed weapons at ranges up to 5 m. This breadboard sensor has produced the only remote ultrasound images of concealed weapons ever published, including lexan (plastic) knives and a handgun concealed under a heavy sweatshirt at 15 feet. The remote imaging by ultrasound was made possible by several new technological developments. The sensor includes a novel, highly efficient source of high-power, tunable ultrasound radiation suitable for remote imaging in air. Together with millimeter-sized, highly sensitive ultrasound detectors and high-gain transceivers, these advances make possible the centimeter- resolution imaging of concealed weapons at ranges between 1 m and 5 m. The ultrasound images are processed by our IMAGE binary-thresholding program, which filters for noise, frequency, brightness, and contrast. To be developed is a brassboard sensor with an imaging array of ultrasound detectors, capable of real-time, video-frame-rate imaging of weapons concealed on moving humans.