Inversion Algorithm And Experiment Of Atmospheric Aerosol Particle Spectrum For Multi-Wavelength LED Light Source Radar

Aerosol is an important part of the atmosphere,which plays an important role in the balance of Earth's atmospheric radiation and the atmospheric quality of the region and the global climate change.The distribution of aerosol particles is the important property of aerosol particles.Different sizes of aerosol particles have different threats to the human.Therefore,it is of great practical significance to study the distribution of aerosol particles.At present,most of the measurements of aerosol particle size are concentrated in the use of laser radar and other instruments.this method can be carried out on the aerosol real-time space detection,but its wavelength is limited.So this paper presents a new detection method to detect the atmosphere with high-power LED light source radar.Its wavelength is rich,but also can suffice the atmospheric aerosol real-time space detection.In this paper,the basic principle of Mie scattering and particle size measurement are introduced at first.The extinction efficiency and scattering efficiency of each wavelength are calculated,and the relationship between the spectral function and the optical parameters is deduced.On the basis of this method,the spline interpolation function is designed by using the idea of numerical approximation,and the algorithm of particle inversion is designed according to the Phillips-Twomey regularization method.The detailed process of the inversion algorithm is deduced.Finally,a series of solutions are deduced to obtain the aerosol particle spectral distribution function.Then,based on the theoretical design of the aerosol particle inversion algorithm,three different inversion methods of three wavelengths,four wavelengths and six wavelengths are designed.The acommon monomodal spectral function and the bimodal logarithmic normal spectral function are selected.The spectral inversion of three different types of aerosol particles is reconstructed by using the inversion algorithm.Effective radius and population volume and its error are analyzed.Finally,based on the theoretical design and numerical simulation,three different wavelengths of high-power LED are selected as the light source of the radar system to detect the atmosphere.The filter signal is filtered by the filter,and then the filtered light is connected to the photoelectric conversion instrument,and then the experimental data are collected by the oscilloscope.The collected experimental data are analyzed and processed,and the aerosol particle spectrum distribution in the actual weather condition is obtained.The experimental results show that the multi-wavelength LED light source radar is used to detect aerosols in two different seasons in Xi'an.The experimental results of the particle spectrum distribution in the inversion algorithm are similar to the simulation results.It is shown that the particle inversion algorithm can be used to invert the spectral distribution of atmospheric aerosol particles.At the same time,it also shows that the LED light source radar built in this paper can be used to detect aerosols in different weather conditions.