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题名	空间目标光度测量方法研究
作者	李冬宁
学位类别	博士
答辩日期	2015-05
授予单位	中国科学院大学
导师	陈涛
关键词	空间目标 光度测量 EMCCD 高斯算法 孔径测光
其他题名	Study on photometric of space target
学位专业	机械电子工程
中文摘要	随着世界各国对地球外太空的军备竞争，空间目标尤其是人造空间目标的数量逐年递增，利用光度信息对这些目标的监控与判断也逐渐成为研究的热点方向，利用地基光电观测设备进行光度测量从而对目标的状态进行判定成为主要手段之一。 光度测量设备是通过观测空间目标的光度变化情况来确定目标的材料以及姿态运动方式等信息的一种高精度测量设备，它通过光电观测设备得到空间目标位置信息，通过高灵敏度的探测器件得到目标的灰度信息，通过光度测量软件得到实际需要的光变曲线，从而实现对目标姿态、物理性质等状态信息的判断。 本文以大型光电观测设备为平台，光度测量系统为研究对象，以提高空间目标光度信息测量的快速性与准确性为目的，针对现有测量方法的缺陷与不足，在模型推导、系统设计、图像处理、测量方式等方面进行了设计与研究，提出了相关算法与改进措施，完成的主要工作归纳如下： 推导了光度测量系统探测能力的数学模型，对系统探测能力进行了仿真，为系统设计与实现提供理论依据；推导了图像坐标系、天球坐标系以及地平坐标系间的坐标转换模型，为目标位置信息在各个坐标系下转换提供理论依据；推导了太阳、空间目标、观测设备间的位置矢量关系，建立了以相位角数据为横轴的测光曲线，为光度数据归一化提供了依据。 设计了适用于光度测量的折反射式光学系统，以经典牛顿式光学系统为基础，通过次镜与场镜的合理运用，实现了1m口径，视场角1.328°，拉赫不变量为5.792的技术指标，不仅视场扩大的同时获得了较好的成像质量，而且缩短了筒长，抑制了鬼像，提高了对暗弱星等的探测能力。 针对拖尾星象的实时处理问题，提出了一种基于定位信息的自适应阈值测量方法。根据目标与定标星的位置信息，对相应区域进行开窗操作，采用快速迭代最大类间方差阈值算法对开窗区间进行分割，避免了其他星象对目标区域阈值选取的影响，与传统分割算法相比，降低了算法复杂度，提高了运算速度。 针对事后高精度光度值提取，提出了一种改进的主动轮廓法。根据构造的流向标量场（FDS场），选取适当阈值进行种子选取，并通过改进的区域生长法进行初始分割，最后根据区域邻接图进行区域合并。与传统蛇模型相比，抗噪性强，提高了运算速度。 结合工程实际，采用了宽谱段测量和滤光片测量两种方式，宽谱段测量方式信噪比高，可探测的极限星等为16等星，在19等天光背景下测量精度可达0.15星等左右，滤光片测量方式在相同信噪比下可探测极限星等为14等星，19等天光背景下测量精度可达0.02星等左右。 综上，本文搭建了米级光度测量平台以及面向用户的测量软件，对系统参数进行了标定，验证了本文算法，在实际工程中得到了应用。
英文摘要	As the armament competition about outer space of the earth among various countries in the world, especially the number of artificial space target is increasing year by year, using ground-based optoelectronic observation equipment for photometric measurement become one of the main method to determine target state. Photometric measurement equipment is high precision measuring equipment to determine the target material and posture movement way through the observation of space target luminosity changes using ground-based optoelectronic observation equipment. Space target is obtained by photoelectric observation equipment location information, gray level information of target is obtained by high sensitivity detector, the actual need light curve is obtained by photometric measurement software, to determine state information like target posture、physical properties. Based on large photoelectric observation equipment platform, research object is the photometric measurement system, for the purpose of improve the rapidity and accuracy of measurement space target photometric information, in view of the defects of the existing measuring methods, design and research the model at aspect of designed system, image processing and measuring way. The main work summarized as follows: Mathematical model of detection ability of photometric measurement system was deduced, system detection ability was simulation, provide theoretical basis for system design and implementation; Coordinate transformation model was deduced among the image coordinate system, celestial coordinate system and the horizontal coordinate system, provide theoretical basis for target location information in various coordinates transformation; The position vector relationship among the sun, space target and observation equipment was deduced; Set up the phase angle data for photometric curve of the horizontal axis, provide the basis for photometric data normalization. Refractive and reflective optical system which apply to photometric was designed, achieved the 1 m diameter, view Angle is 1.328 °, lage invariant is 5.792, based on the classic Newton type optical system and audition and reasonable use of field lens. Not only the view of expanding at the same time get better image quality, and shorten the tube length, suppresses the ghost, improve the detection ability of faint magnitude. To solve the problem of trailing target real-time processing, this paper proposes a adaptive threshold measurement method based on location information. According to the target location information with reference star, open a window to the appropriate area for operation, using the fast iterative between-cluster variance threshold algorithm to split window range, to avoid the other star of the target area, the influence of threshold value compared with the traditional segmentation method, reduces the algorithm complexity and improves the operation speed. For high-precision extraction photometric values, an improved active contour method is proposed. According to the structure of the flow direction scalar field (FDS), select the appropriate threshold to seed selection, and the initial segmentation by an improved region growing method, according to the region adjacency graph of region merging. Compared with the traditional snake model, this algorithm has strong noise resistance, improves the operation speed. To combination with the engineering practice, adopts the wide spectrum measurement and filter measurement, the wide spectrum measurement way's signal-to-noise ratio is high, the detectable limit magnitude is 16 magnitude in the 19 magnitude skylight background, measurement precision can reach 0.15 magnitude, the filter measurement way under the same SNR detectable limit magnitude is 14 magnitude at 19 magnitude skylight background, measurement precision can reach 0.02 magnitude. In conclusion, this paper has set up a platform with meters level caliber and user-oriented measurement software, calibration the parameters of the system, verify the algorithm, this paper have been applied in actual engineering.
公开日期	2015-12-24
内容类型	学位论文
源URL	[http://ir.ciomp.ac.cn/handle/181722/48856]
专题	长春光学精密机械与物理研究所_中科院长春光机所知识产出
推荐引用方式 GB/T 7714	李冬宁. 空间目标光度测量方法研究[D]. 中国科学院大学. 2015.

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