一种基于增采样的干涉SAR相位解缠方法

An InSAR Phase Unwrapping Method Based on Incremental Sampling

干涉合成孔径雷达测量地形高程时,复杂地形区域的干涉条纹过密会导致干涉相位解缠失败,从而使得无法精确获得地形高程信息。该文提出一种降低错误解缠率的新方法,通过对干涉复图像进行增采样,使得干涉条纹相位梯度降低,从而降低相位滤波和相位解缠处理的难度,降低相位解缠的错误率。利用干涉复图像频率与Nyquist频率之间的关系,进行所提方法对地形的适应性分析。理论分析和仿真结果验证了所提方法的有效性,尤其是对于符合Nyquist采样的大坡度区域,该方法有很好的滤波和解缠效果。该文提出的方法不需要增加额外数据,实现简单,运算速度快,可应用于干涉合成孔径雷达的地面处理系统中。

When interferometric SAR is used to measure the terrain elevation, the dense interference fringes in the complex terrain will lead to phase unwrapping failure, so that the terrain elevation information can not be obtained accurately. In this paper, a new method to reduce the error rate of phase unwrapping is proposed. The interference fringe gradient is decreased by increasing the size of the interference complex image, and the difficulties of phase filtering and phase unwrapping is reduced. Based on the relationship between the complex image frequency and the Nyquist frequency, the adaptability of the proposed method to the terrain is analyzed. The effectiveness of the proposed method is verified by theoretical analysis and simulation. Especially for the large gradient region conforming Nyquist sampling, this method has good filtering and unwrapping effect. The method proposed does not need extra data, is simple to implement and fast in operation, and can be applied to the ground processing system of interferometric SAR.