阵列天线微动对前视SAR成像影响及补偿研究

摘要

基于阵列技术的前视SAR能对载机前方区域高分辨成像,但阵列天线的微动会对成像产生影响.该文提出了基于时频分析提取微动特征参数的方法,研究了阵列天线微动对前视SAR成像影响及补偿问题:基于前视SAR阵列天线特点对阵列天线微动进行建模,并分析了阵列天线形变的补偿方法.然后基于时频分析方法讨论了阵列天线微动的时频特性并对参数进行了估计.最后在天线微动条件下对点目标进行了成像仿真,并结合成像特征对天线微动补偿前后的结果进行了分析比较.结果表明该文所建模型和所提算法是正确和有效的.%Airborne forward-looking SAR based on array technology can supply high-resolution images of the area with respect to forward direction of the flight path. However, micro-motion of the array antenna may affect imaging. Extraction method of micro-motion characteristic parameters based on time-frequency analysis is proposed, and influence of array antenna micro-motion on forward-looking SAR imaging and the compensation method are investigated. Firstly, micro-motion model of array antenna is established based on antenna characteristic of forward-looking SAR, and compensation method of array antenna deformation is analyzed. Then, time-frequency characteristic of array antenna micro-motion is studied based on time-frequency analysis method. Finally, imaging simulation of point target in the condition of antenna micro-motion is done. Imaging results before and after compensation are compared combined with imaging characteristic. Results indicate that the established model and proposed method are correct and valid.