Design And Experimental Observation Of Micro-pulse Lidar System

Atmospheric aerosol,as an important part of the bottom atmosphere,plays an important role in many climate phenomena.Research carried out in this paper based on atmospheric remote sensing detection of micro pulse lidar.Introduced new optoelectronic devices,a micro pulse Mie scattering lidar system was designed and developed.Taking aerosols in the northern suburbs of Nanjing as the research object,effective observation of atmospheric visibility.The specific research contents are as follows:1.According to the atmospheric aerosol scattering theory,the inversion method of aerosol extinction coefficient is discussed in detail.Considering the factors such as system portability,cost and overall performance,an eye-safe micro pulse Mie scattering lidar system was designed and developed.The system adopts coaxial transmit and receive antenna design,and introduced new optoelectronic devices such as multi-core fiber,narrow-band filter and photomultiplier tube,which effectively improves the detection performance.2.The experimental observation of atmospheric aerosol in the northern suburbs of Nanjing was carried out by using the micropulse lidar system.The system uses a pulsed laser with a wavelength of 532 nm and a frequency of 5 kHz.In sunny weather,the maximum detection distance of near-surface aerosol is 4-5km(daytime),6-8km(nighttime)and the resolution of distance is 15 m,which verified the feasibility and effectiveness of the system.3.For the lidar echo data,the empirical mode decomposition algorithm is used to filter the noise efficiently.The Fernald backward integral model is used to obtain the atmospheric extinction coefficient profile,and the visibility formula is used to calculate the atmospheric visibility.The visibility value is compared with the results of the commercial scattering visibility meter,and the mean square error is 8.2%,indicating that the lidar system has good accuracy and stability,and can meet the detection requirements of near-surface atmospheric visibility,in meteorological detection and environmental monitoring has broad application prospects.