| The tropospheric and stratospheric atmospheric wind fields have an important impact on human production and life,and lidar has the advantages of high resolution and high sensitivity,and is one of the most effective ways to detect the atmosphere in this region.Due to the small amount of tropospheric and stratospheric atmospheric wind field observation data,the accuracy is not high,and the lidar is vulnerable to the influence of weather conditions,resulting in the decline of measurement accuracy.In order to meet this need,the performance of wind measurement lidar with different wavelengths under different weather conditions is simulated and analyzed.According to the simulation results,a rotating platform-based wind measurement lidar system is developed,and the observation results are compared and analyzed.The paper firstly simulates the detection performance under different weather conditions,and determines the system wavelength as 532nm according to the environment.Secondly,build the wind speed simulation model,this article analyzes the system detection performance for daytime,nighttime and pollution weather,and verifies and analyzes the transmission error of the system.In order to improve the detection accuracy of the system,simulation analysis of aerosol and temperature is then carried out to explore the influence of both on the wind measurement performance of the system.The simulation results show that the detection altitude is 25～30km during daytime,40～45km during nighttime,and 28km during polluted weather.According to the simulation results,the structure of the tropospheric stratospheric Doppler wind measurement lidar system is designed,and the system is built,including the selection and commissioning of telescope,detector,acquisition card,beam expander,integrating sphere and turntable,and the locking procedure of laser frequency and system acquisition control software are designed.The results show that the maximum height that the system can detect in daytime is 25km,and the maximum height that can be detected at night is 38km.The paper analyzes the observation results of the system and uses a data fusion algorithm to process the wind measurement data.The results show that the algorithm can effectively combine the advantages of analog(AD)signals and photonic(PC)signals,which is conducive to improving the wind measurement accuracy.The results show that the wind speed and wind direction profiles measured by lidar are consistent with the trend of the sounding data,which verifies the accuracy of the system in detecting the atmospheric wind field.The continuous wind speed profiles under different weather conditions are compared and the radial wind speed profiles are analyzed.The results show that taking the height with random error less than 5m/s as the maximum detection height,in the case of no cloud,the maximum radial detection height is 14.5km,while in the case of thin cloud,the matximum radial detection height is 12km,and in the case of two layers of cloud,the maximum radial detection height is only 10km.The signal-to-noise ratio and radial wind speed profile of measured data and simulation data under different weather conditions are compared.The results show that the detection height is lower than the simulation results,and this phenomenon is analyzed.According to the analysis results,the performance of wind lidar at different wavelengths is simulated.The results show that the effective detection height of 355nm is the highest on clean days,that is,when the AOD is less than 0.2;When the AOD is greater than 1.6,the effective detection height of 1064nm is the highest.When the optical effective thickness is greater than 2 nm,it has a maximum detection height of less than 531.2 nm.The analysis provides support for obtaining the all-weather tropospheric and stratospheric atmospheric wind field for a long time in the future. |
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