抄録
This paper attempts to extract urban anisotropic features from two Seasat-1 SAR images with different look directions. Study areas are located in Los Angeles and neighbors of South California, U.S. The sets of data from ascending and descending orbits are used.
A city street pattern and other linear feature oriented perpendicular to the radar beam yield very strong radar returns. Therefore, areas which have the oriented feature have different tones on the images obtained during the two orbits. In order to investigate this influence on SAR images, cluster analysis is applied and eight clusters obtained are identified by the aid of city maps and aerial photographs. One cluster includes airports, parks, and golf courses. These areas have no oriented feature. The other clusters correspond to the city street pattern which has the oriented feature. The street pattern oriented within approximately 10°from normal to the look direction is associated with a distinct cluster. The other street pattern oriented above 10°relates to more than one cluster under the influence of urban density.