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	Initial and comprehensive analysis of PPP time transfer based on Galileo high accuracy service 期刊论文 OAI收割 GPS SOLUTIONS, 2024, 卷号: 28, 期号: 2, 页码: 15 作者: Zhang, Runzhi; Tu, Rui; Lu, Xiaochun; He, Zaimin; Guang, Wei \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2025/04/03 Time transfer Precise point positioning Galileo initial high accuracy service GPS/Galileo
	GNSS Timing Performance Assessment and Results Analysis 期刊论文 OAI收割 SENSORS, 2022, 卷号: 22, 期号: 7, 页码: 10 作者: Zhu, Lin; Zhang, Huijun; Li, Xiaohui; Zhu, Feng; Liu, Yinhua \| 收藏 \| 浏览/下载：41/0 \| 提交时间：2022/08/15 GNSS timing performance time transfer accuracy assessment
	The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文 OAI收割 3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 In the test course of static transfer function of TDI CCD camera because of the influence that gets environmental and artificial etc. factor the value of static transfer function measured at any time is between unceasing fluctuation so make accuracy reduce. To solve this problem a kind of accurate measurement technique of static transfer function is put forward. First before carrying out the measure of static quiet of transfer function the best test point of transfer function of the TDI CCD camera must be determined it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image per 1000 lines of target mark image as a measures sample of static transfer function exclude because of atmosphere tremble twisted vague rectangle target mark image retain 500 distinct and steady target mark image as measure sample set. Then calculate the static transfer function of each measure sample respectively take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923 with before measurement technique comparison the value of static transfer function has raised 0.02 makes the accuracy of the measure of static transfer function have gotten raising.
	Design of ground-based physical simulation system for satellite-borne TDI-CCD dynamic imaging (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China 作者: Zhang L.; Zhang L.; Sun Z. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 As we know the existence of image motion has a bad effect on the image quality of satellite-borne TDI CCD camera. Although many theories on image motion are proposed to cope with this problem few simulations are done to justify the proposed theories on ground. And thus in this paper a ground-based physical simulation system for TDI CCD imaging is developed and specified which consists of a physical simulation subsystem for precise satellite attitude control based on a 3-axis air bearing table and an imaging and simulation subsystem utilizing area-array CCD to simulate TDI CCD. The designed system could realize not only a precise simulation of satellite attitude control whose point accuracy is above 0.1 and steady accuracy above 0.01/s but also an imaging simulation of 16-stage TDI CCD with 0.1s its integration time. This paper also gives a mathematical model of image motion of this system analogous with satellite-borne TDI CCD and detailed descriptions on the principle utilizing area-array CCD to simulate TDI CCD. It is shown that experiment results are in accordance with mathematical simulation and that the image quality deteriorate seriously when the correspondence between the image velocity and signal charges transfer velocity is broken out which suggest not only the validity of the system design but also the validity of the proposed image motion theory of TDI CCD. 2010 SPIE.