基于大气湍流闪烁互相关法的横风探测技术研究OA

To solve the problems of complex equipment in traditional Doppler wind light detection and ranging(LiDAR),high energy requirements of single-transmitter dual-receiver laser detection,and significant blind zones,this study proposes a direct path-averaged crosswind detection system based on the laser scintillation cross-correlation method.The system adopts an integrated single-ended dual-channel transceiver structure using a 1550 nm laser.By constructing multi-layer turbulent phase screen models for simulation and validating with a dual-channel crosswind detection system,the proposed method achieves path-averaged crosswind detection while reducing peak power requirements and enhancing robustness under complex meteorological conditions. In the theoretical study,Mikhail Belenkii's analysis was fully referenced.In a round-trip path,the laser beam propagates through atmospheric turbulence twice:from the transmitter to the target and then back to the receiver.When the system parameters meet the requirements,the intensity fluctuations of the reflected beam on the round-trip path are mainly determined by scintillation along the return path.Based on the above theory,simulations were conducted using the power spectrum inversion method to generate atmospheric turbulent phase screens.A multi-layer vacuum-phase screen alternating transmission model was constructed based on the van-Karman spectrum.The intensity fluctuation characteristics of laser propagation were calculated using a wave optics model.The theoretical feasibility of the scintillation cross-correlation method was verified by comparing the simulation results with the correlation calculation results.In the experimental section,a dual-channel coherent laser detection system was developed using an innovative coaxial dual-transmitter dual-receiver structure.Atmospheric scintillation signals were collected using a 1550 nm laser and high-speed photodetectors.During the data processing phase,signal analysis was performed using a combination of spectral energy extraction algorithms and the zero-mean normalized cross-correlation(ZNCC)algorithm. Simulation results revealed a linear relationship between the cross-correlation peak offset of the echo energy in the round-trip path and the crosswind speed,with a relative error of 3.2％,demonstrating strong consistency and verifying the accuracy of the theoretical model(Fig.5).In the experimental phase,well-designed and reliable comparative tests were conducted.A comparison between the experimental data and reference values from a Doppler wind LiDAR(Fig.10a)showed consistent trends in wind speed fluctuations,with a Pearson correlation coefficient of 0.865.Linear regression analysis(Fig.10b)indicated a determination coefficient R2=0.688 between the experimental data and reference values,with a fitting slope approaching 1 and a root mean square deviation(RMSD)of 0.755 m/s.Residual analysis(Fig.11)validated the normal distribution of errors(K-S test,p＞0.05),and the symmetric distribution of residuals indicated that the system exhibited stable statistical characteristics. Through numerical simulations and experimental verification,this study confirms the effectiveness of the single-ended scintillation cross-correlation method for path-averaged crosswind detection.The innovative coaxial dual-transmitter dual-receiver structure not only reduces the peak power requirements but also enhances system reliability.The high correlation(r=0.865)between experimental results and standard radar data demonstrates that the system can provide reliable data support for meteorological monitoring and engineering applications,laying a foundation for further optimization of algorithm adaptability under different meteorological conditions.