ESTIMATION OF THE WIND ON THE SEA-SURFACE BY USING A NEW POLARIMETRICDESCRIPTOR - THE HUYNEN VECTOR

The polarimetric signature of the sea surface is calculated, by using the small perturbation method, from a two-scale sea surface model. Thi s signature is formalized by the Mueller matrix, whose coefficients ax e functions of the speed of the wind, the incidence of illumination an d the azimuthal direction of the wave with respect to the direction of the wind. The polarimetric signature of the ocean is then described b y the nine Huynen coefficients. In this paper, the cross-correlation b etween these coefficients is shown; a reduction of the polarimetric in formation to a Huynen vector whose dimension is minimal (five) is prop osed. From this defined vector a Bayesian estimator (a maximum likelih ood ratio test) is built, making it possible to estimate the wind dire ction and speed from polarimetric measurements of the sea backscatteri ng.