Simulation research and theoretical study on measurement of atmospheric optical turbulence and wind profile using the correlation of gradient-tilt

doi:10.7498/aps.66.104207

	Simulation research and theoretical study on measurement of atmospheric optical turbulence and wind profile using the correlation of gradient-tilt
	Peng Zhe 1,2; Jing Xu2 ; Hou Zai-Hong2 ; Wu Yi 2
	2017-05-20
发表期刊	ACTA PHYSICA SINICA
摘要	In this article, a theoretical method based on the fluctuation of gradient tilt (G-tilt) of active light source is proposed to estimate the horizontal profiles of atmospheric optical turbulence (C-n(2)) and transverse wind. The G-tilt, related to the average phase gradient, is in the same direction as the average ray direction. And G-tilt angle is considered to be equal to the ratio between the centroid position offset and the focal length. In this method, a theoretical model based on lidar system is set up, in which forward scatter light beams at different distances are taken as beacons. These beacons are detected by a two-aperture telescope. And two light columns, from which we can obtain the information about G-tilt angle, are imaged by these beacons. In order to obtain the turbulence intensity and wind velocity from G-tilt angle with our theoretical model, the differential cross-correlation expressions of G-tilt angle and its derivative are derived in detail. These two expressions are based on the spatial cross-correlation function obtained from Rytov approximation and Taylor's frozen-flow hypothesis for Kolmogorov turbulence. Simultaneously, path weighting functions of C-n(2) and wind velocity are derived, and the effects of path weighting functions on the calculation of our method are analyzed. Based on such an analysis, to realize the inversion of turbulence intensity and transverse wind, the matrix transformation algorithm is proposed. We ignore some minimal values of the path weighting functions in our algorithm so that the ill-conditioned matrix is avoided. Besides, numerical simulation is used for preliminarily validating this method. In our simulation, C-n(2) varies randomly between 10(-15) m(-2/3) and 10(-14) m(-2/3) while wind velocity ranges from 5 m/s to 10 m/s. The sign of the wind velocity represents the direction of wind. According to the simulation results, the horizontal profiles of atmospheric optical turbulence and transverse wind calculated are consistent with their theoretical values no matter whether there exists Gaussian noise. When the ratio between the standard deviation of Gaussian noise we added and the original signal is 0.2, the maximum relative error of logarithmic C-n(2) is 3.4%, and the correlation coefficient between the calculated results and theoretical values for C-n(2) is 0.8. Besides, the maximum absolute error of wind velocity is 1.82 m/s, and the correlation coefficient between the calculated results and theoretical values for wind velocity is 0.9. Even if the horizontal profiles of atmospheric optical turbulence and transverse wind vary largely, the calculation results of our method remain stable. Therefore, a new idea is provided for measuring atmospheric turbulence and wind.
文章类型	Article
关键词	Gradient-tilt Correlation Atmospheric Turbulence Wind Velocity
WOS标题词	Science & Technology ; Physical Sciences
DOI	10.7498/aps.66.104207
收录类别	SCI
语种	英语
项目资助者	National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014) ; National Natural Science Foundation of China(41405014)
WOS研究方向	Physics
WOS类目	Physics, Multidisciplinary
WOS记录号	WOS:000403088000018
引用统计	被引频次：1[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.hfcas.ac.cn:8080/handle/334002/33456
专题	中科院安徽光学精密机械研究所
作者单位	1.Univ Sci & Technol China, Dept Environm Sci & Optoelect Technol, Hefei 230026, Peoples R China 2.Chinese Acad Sci, Anhui Inst Opt & Fine Mech, Key Lab Atmospher Composit & Opt Radiat, Hefei 230031, Peoples R China
第一作者单位	中科院安徽光学精密机械研究所
推荐引用方式 GB/T 7714	Peng Zhe,Jing Xu,Hou Zai-Hong,et al. Simulation research and theoretical study on measurement of atmospheric optical turbulence and wind profile using the correlation of gradient-tilt[J]. ACTA PHYSICA SINICA,2017,66(10).
APA	Peng Zhe,Jing Xu,Hou Zai-Hong,&Wu Yi.(2017).Simulation research and theoretical study on measurement of atmospheric optical turbulence and wind profile using the correlation of gradient-tilt.ACTA PHYSICA SINICA,66(10).
MLA	Peng Zhe,et al."Simulation research and theoretical study on measurement of atmospheric optical turbulence and wind profile using the correlation of gradient-tilt".ACTA PHYSICA SINICA 66.10(2017).