基于星地联合的国产遥感卫星高频姿态误差探测与补偿技术研究

The impact of the high frequency attitude error on satellite image internal geometric accuracy is trouble in image product processing recently. The attitude error detection and correction become a key technology to be solved urgently. In this project we employ a novel approach combined with satellite and ground data for detecting the change regularity of high frequency attitude error. The high frequency attitude error variation is detected accurately with a frequency spectrum analysis based on Fourier Transform (FT) and an improved phase-correlation method based on augmented sinc core function interpolation, respectively from raw star tracker/gyro data and simulated image. On this basis we proposed trigonometric series to build the relation model between error and sampling time, and the satellite high frequency attitude error compensation model parameters are accurately estimated by Least Square Method (LSM) and augmented Kalman filtering algorithm. The test data from domestic remote sensing satellite such as ZY-3 et al. are used to compare and validate the image internal geometric accuracy before and after the satellite high frequency attitude error compensation. This research result will improve remote sensing satellite image internal geometric accuracy, and provides a technological support for satellite larger scale topographical mapping.

高频姿态抖动对遥感卫星影像内部几何精度的影响是近年来卫星影像数据处理不可忽视的问题，探测和校正高频姿态抖动成为目前亟待解决的关键技术之一。本项目拟采用星地联合的高频姿态误差规律性探测方法，以星敏陀螺原始测量数据和地面仿真影像为参考，采用傅里叶变换和多维sinc核内插的频域相位相关算法，通过对原始姿态频谱分析和卫星影像匹配来探测高频姿态抖动变化规律。并在此基础上，利用三角函数级数表达形式，建立高频姿态误差随时间变化的关系模型。最后，通过最小二乘和扩维卡尔曼滤波动态估计精确计算模型未知参数，完成卫星高频姿态抖动误差补偿。项目以国产测绘遥感卫星如资源三号等为试验对象，利用密集地面控制对高频姿态误差补偿前后卫星影像内部几何精度进行分析和对比,验证方法的实用性和可靠性。本项目的研究有望进一步提升国内外遥感卫星影像内部几何精度，为国产遥感卫星大比例尺测图提供技术支撑。

姿态是影响遥感卫星的几何定位精度最重要的影响因素之一，特别是卫星平台高频颤振对高分辨率卫星影像产品的影响尤为突出。为了探索国产遥感卫星平台高频颤振规律，本项目重点研究高频姿态误差探测与补偿处理技术。（1）实现了多光谱匹配和基于星敏感器和陀螺仪的颤振频域分析方法，发现资源三号01/02星都存在0.65Hz的高频颤振；（2）提出了基于像方高精度密集匹配的高频姿态误差探测方法，完成了姿态高频抖动相对到绝对的转化，实现姿态抖动复原，抖动复原精度优于0.2个角秒。（3）构建了基于三角级数拟合的高频姿态误差模型，拟合后的绝对姿态误差优于0.6个角秒。利用在轨资源三号卫星开展了高频姿态误差校正与验证，进一步挖掘了卫星在轨姿态测量数据的精度潜能。通过本项目的研究，为国产遥感卫星高频姿态误差探测与补偿提供了技术支撑，也为后续国产遥感卫星的参数研制设计提供了参考依据。