URBAN BUILDING HEIGHT ESTIMATION FROM RADARSAT 2 IMAGERY, A CASE STUDY IN BEIJING, CHINA

A method of building height extraction from multi-polarization SAR imagery, taking radarsat-2 as an example, was proposed based on backscatter model. First, the connected component of double-scatter of the buildings in the image was analyzed and its contribution to radar cross section was got simultaneously. a case study in urban areas of Beijing, China. Then, optimal polarized combination was utilized, which was extracted by using backscatter model from the solution of geometrical-optics physical-optics (Go-Po) first-order approximation and by comparing the results from four training areas at the same time. The experimental results show that optimal polarized combination produces much less errors than single polarization method in extracting the height of research area, with 81.43% of buildings whose absolute errors are less than five meters, 4.45 of root mean square error and 0.91 of relation coefficient with Aster GDEM, which proves that the result in height extraction is reliable.