A Flexible and Computationally Efficient Density Model for the Multilook Polarimetric Covariance Matrix

Abstract:
We propose a complex Wishart-Kotz-type I distribution for the polarimetric covariance and coherency matrix. This is a very flexible density model for multi look polarimetric radar data, which can account for severe radar texture with different characteristics. Contrary to alternative models, the closed form expression of the distribution contains no special function, which makes its application to image analysis algorithms both computation ally efficient and numerically stable. Parameter estimators based on the method of matrix log-cumulants have been developed and the flexibility of the new distribution has been favourably compared to some common models.