Wind direction ambiguity removal by using RADARSAT-2 polarimetric SAR images

A new approach for the wind directions ambiguity removal is proposed. An ambiguity (180° ambiguity) remains on wind directions extracted from Synthetic Aperture Radar (SAR) images. Algorithms based on the detection of geometrical forms in ocean surface are currently used to extract the wind directions from SAR images. The approach proposed in this study is based on signal phase difference through the sea surface. The results show wind directions located at a distance less than 2km are subjected to the wave breaking effects and do not have the same threshold (reference phase) as those located offshore (>10km). Furthermore, a reference phase based on inter-channel phase combination allows an automatic removal of the ambiguity.