系统工程与电子技术

• 传感器与信号处理 • 上一篇    下一篇

高分辨圆迹环扫合成孔径雷达成像方法

廖轶1,包敏2,邢孟道1,保铮1   

  1. 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;
    2. 西安电子科技大学电子工程学院, 陕西 西安 710071
  • 出版日期:2013-09-17 发布日期:2010-01-03

High resolution imaging algorithm for circular trace scanning synthetic aperture radar

LIAO Yi1,BAO Min2, XING Meng-dao1,BAO Zheng1   

  1. 1. National Laboratory of Radar Signal Processing, Xidian University, Xi’an 710071, China; 
    2. School of Electronic Engineering, Xidian University, Xi’an 710071, China
  • Online:2013-09-17 Published:2010-01-03

摘要:

圆迹环扫合成孔径雷达(circular trace scanning synthetic aperture radar, CTSSAR)是一种新型合成孔径雷达(synthetic aperture radar, SAR)成像模式,受其圆弧飞行轨迹的影响,直线运动轨迹模型下的成像算法不再适用。针对这一问题,提出了一种新的CTSSAR成像方法。该方法首先在误差允许的范围内对其圆弧运动轨迹下的斜距方程作四阶近似,再求解方程得到驻相点的精确解析解,获得信号的二维频谱,并以此推导了相应的成像算法,补偿了不同距离处的目标的相位,实现高分辨率成像。在整个的推导过程中只做了一次合理的高阶近似,因此获得的二维频谱具有较高的精度。同时对于实际中可能遇到的运动误差问题,给出了一种解决思路。最后,点目标的仿真对比结果验证了成像算法的有效性与运动补偿方案的可行性。

Abstract:

Circular trace scanning synthetic aperture radar (CTSSAR) is a new imaging mode, the linear trajectory module does not hold due to the impact of its circular trace. To deal with this problem, a new imaging method is proposed. Firstly, the target range function is expanded to a quartic polynomial which meets the limitation of errors. After that, the stationary point is solved and the two dimensional spectrum is obtained, based on which the corresponding imaging method is derived. There is only one high order approximation of the range in the whole derivation procedure so that the obtained twodimension spectrum owns high accuracy. Meanwhile, a solution to the problem of motion errors appeared in practice is presented. Finally, the effectiveness of the proposed approach is validated by the point target simulation and comparison, and the feasibility of the motion compensation method is verified.