Fine Detection Technology Of Atmospheric Aerosol Optical Parameters In Near Infrared Wavelength

Atmospheric aerosol is an important substance to study the climate and radiation characteristics of the global environment.Aerosol's optical parameters such as extinction coefficient,backscatter coefficient,and radar ratio are very important for analyzing the particle size,type,microphysical parameters of aerosols in the atmosphere and studying the scattering properties of aerosols.Laser at the wavelength of 1064nm has strong cloud and dust storm penetration,and is widely used in the lidar detection for cloud and aerosol.However,because of the weak Raman and Rayleigh signal in this band,the independent detection of the optical parameters at 1064nm for aerosol has not been breakthrough.This paper mainly focused on the research of high-spectral-resolution laser radar detection technology in the near infrared wavelength,which includes three parts:theoretical research,system testing and atmospheric observation.According to the characteristics of the 1064nm wavelength atmospheric backscatter spectrum,a high spectral resolution laser radar inversion algorithm based on frequency correction technology is proposed,the error transfer analysis is carried out,the influence of the spectral separation comparison on the detection results is studied.A set of frequency monitoring system is designed to realize the real-time monitoring of the frequency drift of the system,The 1064nm high-spectral-resolution Spectroscopic system is Optimized.The spectroscopic property of the hyperspectral Fabry-Perot etalon(FPE)in the hyper spectral resolution system has been tested and the performance parameters of the FPE-half full width(FWHM)and free spectral range(FSR)are calibrated accurately.The FWHM is calibrated to be 1.1pm(291.5MHz)and FSR is calibrated to be 45.9pm(12.1GHz).The results are consistent with the theoretical design value;the HSRL at 1064nm is constructed and the atmospheric observation experiment is carried out to obtain the effective aerosol scattering signals in the boundary layer of Xi'an city.According to the high-spectral-resolution inversion algorithm,the independent aerosol backscattering coefficient,extinction coefficient and radar ratio data are successfully retrieved.