Characterization of UXO-like targets using broadband electromagnetic induction sensors

We have inverted broadband electromagnetic induction data over an isolated target to determine its electrical conductivity, magnetic permeability, radius, and depth using a sphere model. Studies using synthetic data of a concentric, broadband, electromagnetic sensor indicate that the technique is dependable and produces fastconverging solutions. The geometrical parameters obtained through this technique are very close to true values, and the electric parameters for noise-free data are correct to within a few percent. When 10% noise is added to the data, the geometric parameters are still well determined, but the electric parameters are poorly resolved, particularly for a sphere that is both conductive and permeable. Tests on the experiment data show that volumeequivalent size and depth to a target can be reasonably estimated for a nonspherical object.