基于辐射状靶标的MTF评估算法及精度分析研究

A Research on MTF Estimation and Accuracy Analysis based on Radial-target Method

辐射状靶标既可以检测光学遥感载荷的空间分辨率,还可以评估载荷的MTF,因此广泛应用于光学遥感载荷在轨性能评估与数据质量分析中。通过仿真分析方法,对基于辐射状靶标的MTF评估算法进行了改进,并进行了精度分析。分析结果可为靶标布设以及实施辐射状靶标法在轨MTF评价提供理论指导。

Modulation Transfer Function(MTF)is one of the most comprehensive and standard measure to characterize the performance of optical remote sensing payload.Estimation methods of MTF can generally be divided into three-bar method,point source/array method,pulse method,knife-edge method and radialtarget method according to the target.Among those methods,radial-target method,due to its unique geometric structure,is relatively straight but more fully to characterize the spatial performance.Within this paper,the MTF estimation algorithm based on radial target is improved,and an assessment accuracy of the improved algorithm is analyzed:the main factors and their impact on MTF estimation accuracy in radial-target method is stressed based on theoretical analysis and simulation experiment,including detection threshold,the number of detection bars,target width,target deployed angle,the random noise during image acquisition,and so on.The analysis results give some suggestions on the target deployment,and provide theoretical guidance for the on-orbit MTF estimation based on radial-target.