双发模式下视三维SAR成像方法研究  

Study on Imaging Method of Downward-Looking 3-D SAR Based on Double Transmitting Antennas

作　　者：彭发祥[1] 李宏伟[1] 蔡斌[1] 张建忠[2] 

机构地区：[1]空军工程大学电讯工程学院 [2]中国人民解放军94159部队52分队

出　　处：《计算机仿真》2012年第7期238-242,263,共6页Computer Simulation

摘　　要：在合成孔径雷达(SAR)成像优化过程中,由于受到地形环境噪声的影响,使成像模糊和信息丢失,利用阵列天线SAR(LA-SAR)进行成像是一个不错的解决方法。然而传统的单发模式要求有足够多的阵元以满足空间采样率的要求,工程实现的难度较大。为解决上述问题,提出了一种采用正负斜率线性调频信号的双发模式下视三维SAR成像新方法,可以大幅减少天线阵元的数目,提高雷达平台的空间利用率,有效降低工程实现的难度。分析校正了俯仰向的距离徙动因子,给出了双发模式下回波信号的处理方法。进行仿真的结果证明了改进的三维成像方法对成像优化的有效性。In the optimization of synthetic aperture radar （ SAR）, terrain ambient noise can cause the problems such as image blur and information loss. To obtain accurate image by linear arrays, SAR （LA-SAR） is a good meth- od to solve the problem. Conventional LA-SAR with single transmitting antenna requires a lot of receiving antennas to meet the request of spatial sampling rate, which is difficult to implement. In order to settle the problem, a new ima- ging method of down-looking 3-D SAR based on chirp-up chirp-down signals was proposed, which can cut clown the number of antennas significantly, improve the spatial efficiency of radar platform and reduce the difficulty of project implementation. The range migration factors along elevation direction were discussed and corrected, and the proce- dures for chirp-up chirp-down echo signals were given. The validity of the improved 3-D imaging method was vali- dated by the simulation results.

关 键 词：合成孔径雷达 三维成像 下视成像 等效相位中心原理 

分 类 号：TN957[电子电信—信号与信息处理]