Analysis of Spectral Data of Manmade Materials, Military Targets, and Background Using an Expert System Based Approach

An expert system developed for use with geologic materials (minerals) has been modified to more generally analyze spectra of all types of materials, including manmade materials, military targets, and background. The methodology requires reflectance spectra, but can also be extended to emissive measurements in the mid-wave infrared (MWIR) and long-wave infrared (LWIR). The spectra of known materials are used as a reference library, which is then analyzed using a continuum-removal/feature-extraction methodology. If multiple measurements of a selected material are present in the library, then these are used to calculate spectral variability and create default tolerances for expert-system rules. The rules are applied against unknown field, laboratory, or hyperspectral signatures in a weighted fashion to identify materials. Implemented as an extension to the “ENVI” remote sensing software system, this approach provides even untrained personnel with the ability to use characteristic spectral properties for analysis of hyperspectral data and spectra from a variety of other sources.