Coherence and the look number-based deformation gradient function model of INSAR

Abstract

A new functional model for determining the minimum and maximum detectable deformation gradients of the interferometric synthetic aperture radar (InSAR) is developed. The model incorporates both the interferometric coherence and the look number, representing an extension to the existing models that consider only the interferometric coherence. Experimental results with Envisat ASAR data show that the new model performs well for interferograms with different look numbers. The model can serve as an important tool in determining whether InSAR technology can be used effectively to monitor a particular given ground subsidence. In addition, the model can also be used to determine the optimum look number for multi-looking operation to result in the best deformation monitoring results.