Development of a monostatic multifrequency electromagnetic mine detector

A new, monostatic, broadband, electromagnetic sensor, known as the GEM-3M, has been prototyped and tested at various sites containing buried unexploded ordnance and mines. The instrument consists of a pair of concentric, circular coils that transmit a continuous, broadband, digitally controlled, electromagnetic waveform. The two transmitter coils, with precisely computed dimensions and placement, create a zone of magnetic cavity at the center of the two coils. A third receiving coil is placed within this magnetic cavity such that it senses only the weak, secondary field returned from the earth and buried target(s). The mine detector is designed for ordinary soldiers, and, when completed, will have the following unique features: (1) one-man portable high-tech mine detector: intelligent, realtime data interpretation and display on a color LCD screen; (2) targets can be metallic mines, nonmetallic mines, or a disturbed soil condition; (3) detection and characterization based on visual color displays, rather than the tonal changes common to current metal detectors; (4) broadband; selectable frequencies for depth scanning suitable for regional soil conditions and geology, and; (5) all sensor coils housed in a light, circular disk - very similar in appearance to a conventional metal detector.