FMCW-SAR高分辨距离成像中混频模式分析与频谱补偿方法  

Analysis of Mixing Mode and Spectrum Compensation Method in High Range Resolution Imaging of FMCW-SAR

作　　者：夏春云[1] 池龙[1] 张群[1] 梁颖[1] 朱蒙[1] 

机构地区：[1]空军工程大学信息与导航学院,西安710077

出　　处：《火力与指挥控制》2013年第10期169-172,共4页Fire Control & Command Control

基　　金：国家自然科学基金(61172169);陕西省自然科学基金(2011NQ8040);陕西省自然科学基金资助项目(2012JQ8036)

摘　　要：调频连续波合成孔径雷达(FMCW-SAR)具有体积小、重量轻、成本低、功耗低等优势,广泛应用于小型平台。分析了FMCW-SAR的"dechirp"处理过程中混频信号选择问题,采用发射信号延迟信号作为混频信号,一定程度上克服了目标回波时延对距离分辨率的影响。但是,在这种混频方式下,当场景宽度较大时,仍然存在带宽损失,影响了距离分辨率。提出通过构造统一的补偿函数对回波信号进行补偿的方法,保证了信号带宽的充分利用,使距离分辨率不受场景宽度的影响。最后仿真实验验证了混频信号选择问题分析的正确性及所用方法的有效性。The FMCW-SAR is widely used on the small platform because of the advantages of miniature ,lightweight, cost-effective and low-power. The problem of choosing mixing signal is analyzed in the ＂dechirp＂ processing. The delayed signal of transmitting signal is adopted as the mixing signal, then the effect on the range resolution of time delay of echo is avoided. But as the imaging scene gets wider,the bandwidth will decrease evidently and the range resolution is reduced. After the unified compensated function is structured to compensate the echo signal in the paper,the bandwidth is fully exploited and the range resolution is unaffected by the width of scene. Some results are given for validating the analysis of choosing mixing signal and the effectiveness of the proposed method.

关 键 词：FMCW—SAR “dechirp” 混频信号 频谱补偿 

分 类 号：TN957[电子电信—信号与信息处理]