多基线干涉SAR的相位估计

An Estimate Method for Multi-baseline INSAR Phase

利用多基线干涉SAR能够获得优于单基线干涉SAR的地形高程图。提出一种多基线干涉SAR的相位估计方法。该方法首先对不同长短的基线对应的两幅复图像进行单基线干涉,得到条纹疏密程度不同的单基线干涉相位图;然后根据短基线和长基线的关系,估计出长基线对应的干涉相位被2π模糊的倍数;最后根据长基线对应的干涉相位的主值和估计出来的模糊倍数恢复出长基线对应的干涉相位。分析了长短基线对应的干涉相位之间的关系,以及对应的干涉相位主值之间的关系;论证了去平地前后该方法的适用性;给出了多基线干涉相位估计方法的实现过程,并用计算机进行仿真,结果验证了该方法简单易行并且有效。

The interferometrie SAR of the multi-baseline is capable of obtaining the higher accuracy of the elevation measuremerit than that of the single-baseline. A phase estimate method of multi-baseline interferemetric SAR is proposed. Firstly, obtained the phases of single-baseline interferometric SAR by two complex images of different baselines and the stripes are distinct due to the varying length of baselines. Then, according to the relationship of the long and the short-baseline, estimated the ambiguity number of the longer-baseline interferometric phase wrapped by the module 2π . Finally, via the wrapped phase added the product of the ambiguity number with the module 2π, gained the unwrapping phase of the longer-baseline. Analyzed the relationship of unwrapping phases and the relationship of the wrapped phases, presented the realizing process of the method, and testified the applicability of the method after reducing the plain effect. Simulate results demonstrate the validity of the proposed method.