| Synthetic aperture radar(SAR) interferometry is an established technique based on combining two SAR images of the same scene acquired from slightly different viewpoints. It is widely used for topographic mapping and surface change detection, moreover, in past few years, SAR interferometry has also been used to retrieve physical parameters of terrestrial surfaces. Polarimetric SAR interferometry is the technique that integrated the radar polarimetry and radar interferometry. Radar interferometry is sensitive primarily to the spatial distribution of vegetation, while polarimetry is sensitive primarily to the shape and orientation of vegetation scatters. Therefore polarimetric interferometry is sensitive to the distribution of orientated scatters. It has been used to invert the terrain surface vegetation parameters, especially for height of forest. It is a leading edge of radar remote sensing in recent years. In this dissertation, based on ERS-1/2 and SIR-C/X-SAR data, the project associating with SAR interferometry and polarimetric SAR interferometry information extraction and application have been extendedly studied. In particular, the basic theory of Polarimetric SAR Interferometry has been detailedly discussed, furthermore, the information extraction and application of Polarimetric SAR Interferometry are extendedly developed. Some new results has been obtained as follows:1. In the area covered by rich vegetation, conventional InSAR can not remove the decorrelation caused by height difference of scattering center inside the resolution elements by spectral filtering, but Ploarimetric SAR Interferometry can effectively remove this kind of spectral decorrelation. The DEM obtained from Polarimetric SAR Interferometry should have higher accuracy than that obtained from conventional InSAR. Based on SIR-C L band complex single look data, one integrity data processing algorithm that generated DEM from Pol-InSAR data has been presented, furthermore, several key problems have been studied. The results indicate that the DEM obtained from Polarimetric SAR Interferometry have higher accuracy than that obtained from InSAR. Also, the error resources that different from the conventional InSAR have been discussed.2. Being the coherent optimization of polarimetric SAR interferometry provided the optimal separation of phase center, it has more advantages to retrieve the terrain surface vegetation parametes than that of conventional InSAR or PolSAR. But it belong to six dimensional inversion problem, It has the ambiguity of low extinction, low height and high extinction, high height of vegetation in coherence and equivalence of topography phase. So using the conventional local optimization algorithm, it often get stuck in a local minimum when algorithm is restarted with different initial guess value. At this dissertation, the simulated annealing algorithm, which can give global solution of problem, has been implemented in order to improve the inversion accuracy.3. Based on dyadic wavelets theory, phase unwrapping theory and the phase characteristics of interferogram. One phase unwrapping algorithm that based on interferometric fringe detection is presented, compared with the other phase unwrapping method that based on the fringe line detection, It have three advantages. First, it can suppress significantly the effects of noise when multi-scale edge detection is implemented. Second, using the space consistency condition of multi-scale local module maximum, the more accurate phase sharp variation edge can be obtained, Third, using the active contour algorithm - GVF (Gradient Vector Flow) snake, it can connect the fringe line when the phase sharp variation edge is seriously corrupted by the noise or the fringe line are closely spaced.4. Being the polarimetric SAR interferometry provided more information than that conventional InSAR or PolSAR, It is advantageous for identification and classification of land cover. Utilizing the fully polarimetric SIR-C L band data and land-use map of study area, the...
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