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极化干涉理论的发展以及全极化卫星的发射,为极化干涉的研究应用提供了广阔的发展空间,开展极化干涉SAR提取DEM的研究对于解决单极化干涉SAR在植被覆盖区DEM提取精度较低的问题具有重要意义。基于山东泰安地区的一对ALOS PALSAR全极化干涉数据,利用相干性最优方法和最大化相位中心分离的方法获取极化干涉信息,并通过对优化后干涉信息的滤波、解缠、基线精确估计等处理来提取DEM,最后将相干优化的结果与传统HH、HV、VV单极化干涉结果进行对比分析。结果表明:优化方法较单极化干涉方法可以有效降低干涉图的噪声,减少相位解缠的残差点,提高解缠相位的质量,并且不同优化方法之间还存在一定差异,数值半径方法获取的DEM精度要好于其他两种优化方法;通过等值线-Goldstein二级干涉SAR滤波方法可进一步提高单极化和优化干涉图的质量,降低残差点,提高相位质量,在水体覆盖的区域通过滤波窗口的设置可以很好地改善DEM的精度。
The development of polarization interference theory and the transmission of all-polarized satellites provide a great space for the research and application of polarization interference. The research on DEM for polarization-assisted SAR extraction is of great importance to solve the DEM extraction of single-polarization interferometry in the vegetation coverage area The problem of low accuracy is of great importance. Based on a pair of polarimetric polarimetric data of ALOS PALSAR in Tai’an, Shandong Province, the coherence optimization method and maximum phase center separation are used to obtain the polarization interference information. The optimized interferometric information is filtered, unwrapped and the baseline is accurate Estimation and other treatments to extract DEM. Finally, the results of coherence optimization are compared with those of traditional HH, HV and VV unipolar interferometry. The results show that the optimization method can reduce the noise of the interferogram, reduce the residual points of the phase unwrapping, and improve the quality of the unwrapped phase compared with the unipolarized interference method, and there are some differences between the different optimization methods. The numerical radius method DEM accuracy is better than the other two optimization methods; through the contour-Goldstein two-stage interference SAR filtering method can further improve the unipolarization and optimize the quality of the interferogram, reduce the residual point, improve the phase quality, in the water covered area by filtering The window settings can be very good to improve the accuracy of DEM.