Spectral Variability of Remotely Sensed Target Materials: Causes, Models, and Strategies for Mitigation and Robust Exploitation

The purpose of this survey is to examine the major causes of spectral variability in target materials, survey some associated physical models, and discuss how hyper spectral analyses can be made more robust to this variability. Although there are many kinds of hyperspectral-image exploitation algorithms (e.g., classification, clustering, and unmixing) [1] and virtually all of them are affected by spectral variability, we will concentrate on the problem of target detection and, more specifically, the detection, identification, and location of particular materials of interest.