Polarimetric Characteristics Analysis of Ship Target and Its Azimuth Ambiguities Based on PolSAR Images

Azimuth ambiguities in SAR image are very common phenomena. The ambiguities are visually identifiable due to their high intensities in low radar backscatter background of sea environment. The ambiguities can be mistaken as ships and cause false alarms in ship detection. Therefore, for maritime applications (i.e. ship target detection), it is important to analyze the characteristic of azimuth ambiguities of targets. By using Eigenvalue-Eigenvector decomposition method, we analyze the polarimetric characteristics of ships and ambiguities. We conclude that the eigenvalues can be used to differentiate ship target and its azimuth ambiguities. One C-band JPL AIRSAR polarimetric data has been chosen to validate the conclusions.