Physical layer mechanisms for coherent change detection

Abstract

Coherent change detection (CCD) is an approach for detecting changes in a region that is based on interferometric-type processing of existing data or imagery. It is utilized in satellite and SAR imagery and is quite successful in the detection and localization of subtle scene changes. This work provides further expansion of the theoretical framework for this approach through the application of fundamental wave scattering principles. It is shown that this approach has an interesting physical interpretation, since it implicitly incorporates, as priors, power or energy-budget issues relevant to wave scattering and reflection phenomena. Moreover, a discussion of an alternative form that is more broadly applicable is provided. This general variant enables the detection of changes or threats (such as intrusion) even if the propagation medium is complex and completely unknown.