Novel Detection of Atmospheric Turbulence Profile Using Mie-Scattering Lidar Based on Non-Kolmogorov Turbulence Theory

Abstract

Turbulence can cause effects such as light intensity fluctuations and phase fluctuations when a laser is transmitted in the atmosphere, which has serious impacts on a number of optical engineering application effects and on climate improvement. Therefore, accurately obtaining real-time turbulence intensity information using lidar-active remote sensing technology is of great significance. In this paper, based on residual turbulent scintillation theory, a Mie-scattering lidar method was developed to detect atmospheric turbulence intensity. By extracting light intensity fluctuation information from a Mie-scattering lidar return signal, the atmospheric refractive index structure constant, Cn2, representing the atmospheric turbulence intensity, could be obtained. Specifically, the scintillation effect on the detection path was analyzed, and the probability density distribution of the light intensity of the Mie-scattering lidar return signal was studied. It was verified that the probability density of logarithmic light intensity basically follows a normal distribution under weak fluctuation conditions. The Cn2 profile based on Kolmogorov turbulence theory was retrieved using a layered, iterative method through the scintillation index. The method for detecting Kolmogorov turbulence intensity was applied to the detection of the non-Kolmogorov turbulence intensity. Through detection using the scintillation index, the corresponding C˜n2 profile could be calculated. The detection of the C˜n2 and Cn2 profiles were compared with the Hufnagel–Valley (HV) night model in the Yinchuan area. The results show that the detection results are consistent with the overall change trend of the model. In general, it is feasible to detect a non-Kolmogorov turbulence profile using Mie-scattering lidar.

Simulating Atmospheric Characteristics and Daytime Astronomical Seeing Using Weather Research and Forecasting Model

“…Figure 13 demonstrates averaged daytime profiles of optical turbulence at the BAO site. The profile shown by the orange line is obtained from the well-known Hufnagel-Valley model, which is determined by the average surface value of C 2 n and by pseudovelocity calculated for the atmospheric layer from 5 km to 20 km [36,37]. To estimate the surface values of C 2 n , we used data from mast measurements of turbulent characteristics (sonic anemometers).…”

LiDAR technology and experimental research for comprehensive measurement of atmospheric transmittance, turbulence, and wind

“…15,23,27,28 And LiDAR can detect atmospheric transmittance, turbulence, and wind data along any designated path on the target path. 3,10,15,22,27 For laser atmospheric transmission, it is possible to accurately obtain the attenuation characteristics and intensity distribution characteristics of the specified direction laser, as well as the information of wind which affects atmospheric transmittance and thermal blooming. 27,29 Due to the transition zone and blind zone of LiDAR, the detection of turbulence in the near field is limited, and real-time detection of turbulence in any direction also faces enormous challenges.…”

“…With the development and progress of computer technology, laser technology, sensors, and other related technologies, there has been significant progress in the methods of obtaining atmospheric transmittance, turbulence, and wind 3 , 10 , 12 – 16 Atmospheric transmittance can be obtained by simulation with atmospheric transport modeling software, but for a real-time changing atmospheric system, there is always a discrepancy between model calculations and actual conditions, so accurate real-time measurements are needed to obtain atmospheric transmittance 14 , 17 – 19 The commonly used direct measurement method is usually to find a star with constant radiation (such as the Sun) and observe this radiation source by optical means (spectrometer, filter, grating, etc.)…”

“…LiDAR detection belongs to remote sensing detection and has the advantages of high spatial and temporal resolution, real-time detection, etc., and is widely used 15 , 23 , 27 , 28 . And LiDAR can detect atmospheric transmittance, turbulence, and wind data along any designated path on the target path 3 , 10 , 15 , 22 , 27 .…”

“…LiDAR detection belongs to remote sensing detection and has the advantages of high spatial and temporal resolution, real-time detection, etc., and is widely used 15 , 23 , 27 , 28 . And LiDAR can detect atmospheric transmittance, turbulence, and wind data along any designated path on the target path 3 , 10 , 15 , 22 , 27 . For laser atmospheric transmission, it is possible to accurately obtain the attenuation characteristics and intensity distribution characteristics of the specified direction laser, as well as the information of wind which affects atmospheric transmittance and thermal blooming 27 , 29 .…”