Model-based characterization of electromagnetic induction signatures obtained with the MTADS electromagnetic array

A sensor response model based on empirically determined orthogonal response coefficients beta is presented for the analysis of electromagnetic inducti on (EMI) sensor data, The model is applied to high-quality survey data from the multi-sensor towed array detection system (MTADS) program. Data from b oth a prepared test range and a live-site survey are analyzed, At the test field, we show that the model successfully reproduces the measured signatur es of ordnance, ordnance simulants, flat plates, and clutter. At the live s ite, fit statistics were collected showing that for the most abundant ordna nce target, 81-mm mortars, the three beta response parameters are distribut ed log-normally, This allows for a simple method of discrimination. A recei ver operating characteristic (ROC) analysis based on this discrimination me thod is performed and the results discussed.