Analysis of polarimetric ship signatures with Radarsat-2 quad-pol imagery

Polarimetric information can be used to characterize the target and benefit for ship classification in SAR image. In this paper, three types of features from fine quad-polarization Radarsat-2 SAR image, such as target to clutter ratio, distribution of scatter point, coherent decomposition component, are analyzed of three types of ships such as bulk carrier, container ship and oil tanker. Preliminary results show that target to clutter ratio is not suitable to discriminate the three types of ships. HH polarization is optimal for ship detection to HV,VH and VV polarization under the condition of the incidence angle of about 48 degrees. Distribution of strong backscattering can reflect the geometry structure of ship in SAR image, and it can be a good feature for ship classification. Furthermore, the feature will be more reliable in higher resolution SAR image. Polarimetric coherent decomposition benefits for understanding scatter mechanism of scatters of different ship. However it has some limitations for ship type recognition. More features and more ship chips should be investigated for the further conclusion.