A variety of metal detectors are available for the detection of buried metallic targets in general and for humanitarian
demining in particular. No one detector is optimal in all environments: variations in soil conductivity,
and more importantly, frequency dependent soil magnetic susceptibility can favor one design over another. The
use of computer modeling for assessing different designs is straightforward in principle, at least to first order,
but still difficult in practice.
The Geophysics Lab of the University of Toronto is attempting to address this problem in two ways. The
first is by assembling the required computational algorithms to do this into a single simulation code with a
straightforward GUI, intended to be public domain as a MATLAB code. The second, the subject of a companion
paper in this conference, is by making measurements of the electromagnetic properties of difficult soils, and finding
semi-analytic representations of these responses suitable for modeling purposes. The final version of the code,
when completed, is to handle single or multiple transmitter and receiver coils of circular or polygonal shape,
general transmitter current waveforms, arbitrary transmitter orientations and survey paths, small targets with
frequency-dependent anisotropic responses (permitting both magnetic and inductive responses to be calculated),
embedded in multi-layered half spaces with both conductivity and frequency-dependent susceptibility (so-called
"difficult soils"). The current state of the simulation code and examples of its use will be described in this paper.