Analyzing Conspicuous Features of a Curved and Graded Bay Bridge on SAR Imagery

Polarimetric NASA/JPL UAVSAR imagery for the curved and graded Coronado Bridge over San Diego Bay, California, USA was analyzed. The bridge was shown with three types of features. Feature 1 consisted of nearly even distributed dots, feature 2 dots and a curved segment, and feature 3 a continuous curved segment. On the basis of the SAR image geometry and polarimetric decomposition method, dots of feature 1 were produced by the double-bounced interactions of the bridge surface and light poles on the far side of the bridge toward the SAR. Dots of feature 2 were from the double-bounced interactions of the ocean surface and light poles on the near side toward the SAR. The curved segment of feature 2 came from the double-bounced interactions of the ocean surface and side of the bridge facing the SAR. Curved segment of Feature 3 was the multiple interactions of the ocean surface and bottom of the bridge.