一种三维地面场景SAR回波仿真的快速实现方法  

Fast method for SAR echo simulation of a three-dimensional ground scene

作　　者：景国彬[1] 张云骥 孙光才[1] 邢孟道[1] 保铮[1] 

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,陕西西安710071

出　　处：《西安电子科技大学学报》2017年第3期1-7,共7页Journal of Xidian University

基　　金：国家高技术研究与发展计划(863计划)资助项目(2013AA122202);国家自然科学基金资助项目(61222108)

摘　　要：针对三维地面场景合成孔径雷达回波仿真中存在计算量巨大的问题,提出了一种基于图形处理单元的合成孔径雷达回波快速仿真方法.首先,采用分形布朗运动模型对数字高程模型数据进行分形插值处理;再对插值后的数据进行小面元剖分并计算了剖分后小面元的后向散射系数;接着利用改进的下视角比较法对三维场景的阴影遮挡进行快速判断;最后详细分析了回波仿真过程中的3个并行层次,设计了核函数,并利用线程外推和归约相加的计算方法,实现了图形处理单元编程架构下三维场景合成孔径雷达回波的快速仿真.利用这种方法对实测数字高程模型数据进行了回波仿真和成像处理,验证了该方法的正确性和高效性.Due to huge calculation of SAR echo simulation of a three-dimensional （3D） ground scene, a fast simulation method is proposed. First, the data of a 3D ground scene are fractionally interpolated based on the Fractional Brownian Motion （FBM） model. Second, the data interpolated are divided into lots of small facets whose precision meets the simulation requirement, the backscattering coefficients of the small facets are calculated. Third, the shaded area is judged by the comparison method of overlook angles. Three parallel levels are analyzed and the kernel function is designed. Finally, the computing method of reduction adding and external thread are also utilized under the framework of GPU in order to get high efficiency. With the methods mentioned above, the imaging result of experimental DEM data verifies the validity and superiority of the proposed method.

关 键 词：三维地面 合成孔径雷达 分形布朗运动模型 阴影遮挡 图形处理单元 

分 类 号：TN957[电子电信—信号与信息处理]