Title :
Analysis of non-Gaussian POLSAR data
Author :
Doulgeris, Anthony ; Anfinsen, Stian Normann ; Eltoft, Torbjørn
Author_Institution :
Tromso Univ., Tromso
Abstract :
In this paper we present a generalised Wishart classifier derived from a non-Gaussian model for polarimetric synthetic aperture radar (POLSAR) data. Our starting point is to demonstrate that the scale mixture of Gaussian (SMoG) distribution model is suitable for modelling POLSAR data. We show that the distribution of the sample covariance matrix for the SMoG model is given as a generalisation of the Wishart distribution, and present this expression in integral form. We then derive the closed form solution for one particular SMoG distribution, known as the multivariate K-distribution. Based on this new distribution, termed the K-Wishart distribution, we propose a Bayesian classification scheme, which can be used in both supervised and unsupervised mode. Modelling and classification is tested on airborne EMISAR data.
Keywords :
Bayes methods; Gaussian distribution; covariance matrices; geophysical techniques; image classification; radar polarimetry; synthetic aperture radar; Bayesian classification scheme; K-Wishart distribution; POLSAR data; SMoG distribution model; airborne EMISAR data; generalised Wishart classifier; multivariate K-distribution; nonGaussian model; polarimetric synthetic aperture radar data; sample covariance matrix distribution; scale mixture of Gaussian distribution model; supervised mode; unsupervised mode; Bayesian methods; Classification algorithms; Closed-form solution; Context modeling; Covariance matrix; Polarization; Radar scattering; Random variables; Shape; Testing;
Conference_Titel :
Geoscience and Remote Sensing Symposium, 2007. IGARSS 2007. IEEE International
Conference_Location :
Barcelona
Print_ISBN :
978-1-4244-1211-2
Electronic_ISBN :
978-1-4244-1212-9
DOI :
10.1109/IGARSS.2007.4422754
