MATERIAL CLASSIFICATION APPARATUS AND METHOD

The present invention provides signification improvements over the apparatus and method disclosed by U.S. Pat. No. 4,922,467. The invention provides an apparatus for material classification and substance identification of an object contained within an enclosure, or buried beneath the ground. The improvements to the present invention include the use of a source of either electromagnetic or acoustic energy, and electromagnetic or acoustic energy receivers, as appropriate. In addition, the present invention discloses the use of energy pulses of differing frequencies, such that the signal processor can compute the rate of change of energy absorption of the substance, as a function of frequency (d&agr;/df). In this way, the apparatus permits the formulation of a highly detailed and accurate object signature, which can be compared with a database of known object signatures for exact substance identification.