实时轨道条件下Sentinel-1卫星影像干涉配准

Sentinel-1卫星步进扫描模式干涉处理方位向配准精度要求达到0.001个像素，通常在精密轨道条件下采用几何配准联合增强谱分集完成影像的配准。但Sentinel-1卫星精密轨道发布较晚，而实时轨道精度较低，几何配准后易导致增强谱分集相位缠绕。为了进一步修正实时轨道条件下的几何配准结果，满足卫星干涉实时处理的需要，选取以点目标为中心的窗口进行相关配准，并对多组Burst配准结果进行拼接处理，以提高相关配准算法的可靠性和精度，确保配准精度满足增强谱分集的要求。

Coregistration of Sentinel-1 TOPS Data for Interferometric Processing Using Real-Time Orbit

An azimuth coregistration accuracy of 0.001 pixel is required for Sentinel-1 terrain observation by progressive scans (TOPS) interferometric processing, which is usually accomplished by a geometric coregestration and enhanced spectral diversity based on precise orbit information. However, the precise orbit information is distributed later than TOPS synthetic aperture radar (SAR) products, and the accuracy of real-time orbits is not high enough, which could result the phase of enhanced spectral diversity wrapped after geometric coregistration. We aim to improve the geometric coregistration accuracy using real-time orbits to meet the requirement of interferometric processing of Sentinel-1. Firstly, the windows centered by point scatterers are selected to perform the cross correlation coregistration. Then, multi-bursts results are mosaicked to improve the accuracy and reliability of cross correlation coregistration approach, which promises the coregistration accuracy for enhanced spectral diversity. Finally, this method is validated by a real case.