Journal of Systems Engineering and Electronics ›› 2013, Vol. 35 ›› Issue (6): 1168-1176.doi: 10.3969/j.issn.1001-506X.2013.06.07

• 传感器与信号处理 • 上一篇    下一篇

基于双曲线性修正斜距模型的弹载SAR成像方法

周松, 杨磊, 周鹏, 邢孟道, 保铮   

  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
  • 出版日期:2013-06-15 发布日期:2010-01-03

Imaging method for missileborne SAR based on model of hyperbolic slant range with linear modifying

ZHOU Song, YANG Lei, ZHOU Peng, XING Mengdao, BAO Zheng   

  1. National Key Laboratory of Radar Signal Processing, Xidian University, Xi’an 710071, China
  • Online:2013-06-15 Published:2010-01-03

摘要:

在弹载合成孔径雷达(synthetic aperture radar, SAR)下降段成像中,由于弹体存在较大的俯冲下降速度和加速度,回波信号的二维频谱表示式难以有效获得,给后续成像处理带来困难。针对该问题,提出了一种基于双曲线性修正斜距模型的弹载SAR成像方法,通过构造双曲函数形式的斜距表示式并引入线性修正因子,对弹载SAR斜距历程进行合理近似|并以修正后的斜距式为基础,利用驻相点原理(principle of stationary phase, POSP)直接求解SAR回波信号的二维频谱|随后根据该频谱表示式设计有效的弹载SAR频域成像算法。该方法下的频谱推导较为简洁,所获得频谱的数学表达式清晰直观,利于成像分析和后续处理。最后的点目标成像仿真验证了该方法的有效性。

Abstract:

Owing to the high diving velocity and acceleration in the downward movement for missile borne synthetic aperture radar (SAR), the accurate expression of SAR echoes in the 2-dimensional (2-D) spectrum is difficult to be derived, which makes the followup imaging processing difficult. To solve this problem, an imaging method for missileborne SAR based on the model of the hyperbolic slant range equation with linear modifying is proposed. By simplifying the range history with a hyperbolic slant range expression and incorporating a linear modifying component, the 2-D spectrum for SAR echoes can be derived via the principle of stationary phase (POSP), by means of which the highefficient frequencydomain SAR algorithm can be well designed. In the proposed method, the derivation of the 2-D spectrum can be simplified and the obtained expression is concise with clearer meanings, which is convenient for signal analysis and imaging processing. Results from point targets simulation are provided to validate the effectiveness of the proposed method.