| Because of its ability not only to produce two-dimensional high resolution images of the scene illuminated, but also to measure complete complex scattering matrix for each resolution cell, and to operate under all weather conditions and all the time, day and night, a Polarimetric Synthetic Aperture Radar (SAR) is playing a more and more important role in gathering the detailed information regarding the geometric and electric structures of surfaces and covers of the earth. Since the real polarimetric SAR data was derived in the mid 1980s, it has been proved that using polarimetric information can improve performance of SAR image processing and application, and not only provide better understanding and interpretation for the radar observations, but also produce more new functions, such as terrain height measured technology. Since 1990s polarimetric SAR (P-SAR) three-dimensional images technology of the scene illuminated has been developed in American. The complex scattering matrixes measured for each resolution cell were gotten by polarization synthesis and made an estimate to co-polarized scattering characteristics and cross-polarized scattering characteristics. And the characteristics have been used to measure terrain height. Because P-SAR sensor is playing a more and more important role in applications in both civil and military areas, it has been placed on an important role by scientists in the world.Polarimetric SAR three-dimensional images technology is a new developing measuring technology. Terrain slope information can be drawn from Polarimetric Synthetic Aperture Radar (SAR) two-dimensional image, so that three-dimensional image can be generated. It differs from two-pass or repeated trace INSAR that uses interference phase method to obtain topography height. The P-SAR three-dimensional image technology uses the Stokes matrix formed by two-dimensional images resolution cells, then applying Polarimetric Synthesize to Stokes matrix can produce polarization signature of the scatter cross-section a-(, x) for any (ellipticity) and (orientation) polarization state. By Computing the between two resolution units, we can estimate terrain azimuthalslopes and derive estimate of terrain elevation. The terrain contour is determined uniquely by Ay/ from azimuth slop on range gates. American began to study P - SAR three-dimensional images technology in 1990s. D.L.Schuler performed the measurement of topography with P-SAR data in surface elevation plot of the Tiefort mountain range in 1994. D.L.Schuler has proved the elevation error from polarometric SAR terrain height measured, compared with the elevation error from INSAR , is same statistically.The main contributions of the dissertation are as following:(1) According to the theories of co-polarization and cross-polarization scattered characteristics, co-polarization and cross-polarization scattering characteristics of typical targets have been analyzed detailedly in this paper. A mechanism is described that rough surface tilted (symmetrical distribution scene) conduces to estimate terrain slope. So, we can estimate an elevation outline of symmetrical distribution scene without any experiential knowledge.(2) After understanding D.L.Schuler's algorithm of steepest ascent, I have developed an improved scheme about the algorithm of steepest ascent. The improved algorithm can search stably and trace accurately up to scattering characteristic maximum. The improved algorithm has been simulated by computer and proved a good capability.(3) For a symmetrical distribution scene, the attitude information of the terrains is included in the variable of the orientation angle of the polarization ellipticity. To find the correct solution of the polarimetric ellipse rotation angle , the algorithm of fuzzy soluted has been proffered and proved in the paper.(4) Polarimetric radar has four receiver channels, which must be balanced strictly in both phases and amplitudes. The paper proves that...
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