Electromagnetic Induction Spectroscopy

Abstract

An object, made partly or wholly of metals, has a distinct combination of electrical conductivity,<br>magnetic permeability, and geometrical shape and size. When the object is exposed to a low-frequency<br>electromagnetic field, it produces a secondary magnetic field. By measuring the secondary field in a<br>broadband spectrum, we obtain a distinct spectral signature that may uniquely identify the object. Based<br>on the response spectrum, we attempt to “fingerprint” the object. This is the basic concept of<br>Electromagnetic Induction Spectroscopy (EMIS). EMIS technology may be particularly useful for<br>detecting and characterizing buried landmines and unexploded ordnance. EMIS should be fully<br>applicable to many other problems where target identification and recognition (without intrusive search)<br>are important. Potential applications may include industrial sorting processes and robotics.