A novel method to estimate underwater marine cultivation area by using SAR polarimetric entropy

This paper describes a technique of extracting underwater laver cultivation nets by using entropy analysis from ALOS-PALSAR polarimetric data in the Tokyo bay. Due to smooth sea surface over the shallow underwater nets, the radar backscatter cross section (RCS) is small (almost noise level) compared with the surface without the nets. This difference can be detected by the X-band TerraSAR-X, but for PALSAR, the difference is too small to detect since both the surfaces are effectively smooth for L-band microwave. We show that polarimetric entropy is an effective means of identifying the underwater nets from the L-band PALSAR data in comparison with the amplitude image.