A Physical Analysis of Polarimetric SAR Data Statistical Models

The random walk model is studied with the objective to obtain a physical explanation for the texture of polarimetric synthetic aperture radar (SAR) data. A simulator is designed to imitate the scattering process under different circumstances, taking into account different distributions for the scatterer number and the scatterer response, as well as mixtures of scatterers. Statistical analysis of the simulated data shows that the distribution of the scatterer response has an effect only when the number of scatterers in a resolution cell is very small, which appears in very high resolution data. Moreover, it is found that both the fluctuation of the scatterer number and the mixture of different targets can give non-Gaussian-distributed data. The mixture of point targets and distributed targets will lead to an extremely heterogeneous appearance, which may be a clue to analyze the urban areas in polarimetric SAR data.