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The Ground Standoff Mine Detection System (GSTAMIDS) is now in the Engineering, Manufacturing and Development (EMD) Block 0 phase for USA CECOM. The Mine Detection Subsystem (MDS) presently utilizes three different sensor technologies to detect buried anti-tank (AT) land mines; Ground Penetrating Radar (GPR), Pulsed Magnetic Induction (PMI), and passive infrared (IR). The GSTAMIDS hardware and software architectures are designed so that other technologies can readily be incorporated when and if they prove viable. Each sensor suite is designed to detect the buried mines and to discriminate against various clutter and background objects. Sensor data fusion of the outputs of the individual sensor suites then enhances the detection probability while reducing the false alarm rate from clutter objects. The metal detector is an essential tool for buried mine detection, as metal land mines still account for a large percentage of land mines. Technologies such as nuclear quadrupole resonance (NQR or QR) are presently being developed to detect or confirm the presence of explosive material in buried land mines, particularly the so-called plastic mines; unfortunately, the radio frequency signals required cannot penetrate into a metal land mine. The limitation of the metal detector is not in detection of the metal mines, but in the additional detection of metal clutter. A metal detector has been developed using singular value decomposition (SVD) extraction techniques to discriminate the mines from the clutter, thereby greatly reducing false alarm rates. This mine detector is designed to characterize the impulse response function of the metal objects, based on a parametric three-pole model of the response, and to use pattern recognition to determine the match of the responses to known mines. In addition to discrimination against clutter, the system can also generally tell one mine type from another. This paper describes the PMI sensor suite hardware and its physical incorporation into the GSTAMIDS sensor modules. This is a time-domain, transient signal metal detector that gives target signal response information of a different nature than that from more conventional continuous-wave (CW) metal detectors. The magnetic design of the GSTAMIDS PMI has very broad-band radiation properties that allow for the required transient eddy current responses in the metallic targets. The design of this detector is unique in that it allows processing of the received signals from targets to begin at the very start of the eddy current decays (t = 0). This then gives the ability to measure and quantify up to three decay terms in the target response, which features unambiguously identify the particular threat target. The results of the data processing algorithms that are used to extract the features used for mine detection are included herein to more clearly show the mine signals.
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