Alos Palsar Scansar Interferometry and Its Application in Wenchuan Earthquake

ScanSAR is a type of SAR imaging technology, in which SAR switches its antenna look angle cyclically to cover several subswaths and therefore to achieve a very wide coverage. Compared with the conventional stripmap mode, ScanSAR has lots of advantages due to its wide swath coverage and moderate resolution. The disastrous Wenchuan earthquake happened on May 12, 2008 caused large scale land deformation far beyond the coverage of a single strip-map mode acquisition. On the other hand, ScanSAR interferometry is an attractive option to monitor the deformation, which is implemented using a pair of L-Band ALOS PALSAR ScanSAR acquisitions in this paper. Firstly each subswath is processed until the differential interogram is generated, then subswath interferograms are mosaicked together to form the entire scene. The ultimate differential interferogram gives an overall view of the land deformation caused by the earthquake.