Validation of Ship Signatures in Envisat ASAR AP Mode Data using AISLive: Data Acquisition, Processing, and Analysis Results

摘要

Ships appear in synthetic aperture radar (SAR) ocean imagery as bright targets against the ocean clutter background. Envisat Advanced SAR (ASAR) Alternating Polarization (AP) mode data acquisitions over the Strait of Dover and the Strait of Gibraltar, two high-density shipping regions with Automatic Identification System (AIS) coverage via AISLive, have provided a large database of validated ship signatures. For each validated ship signature, several metrics were computed including the clutter statistics, the total radar cross section of each ship, and the ship signature length. These metrics were evaluated in terms of the polarization, the local incidence angle, the validated ship length, the target to clutter ratio, and the ship aspect angle. This is a very rich data set that has yielded new observations and insights to ship detectability by SAR. These results could have bearing on the design of future SAR modes or SAR missions, and could be used to improve the performance of ship detection software.