Monte Carlo Method Simulation Of Pulsed Laser Propagation Process In The Dispersive Medium

The plused laser propagation in the dispersive medium and the research of the optical property in the atmospheric is the important content of laser transport theory and optical medium with transmittance-reflection and translucence. At the same time, they all have significant application values in the fields of Radar Detection, Active Imaging, Laser Guidance, Meteorology and Communication technologies.Research and analysis the plused laser propagation in atmospheric dispersion medium by Monte Carlo method on the basis of research on photon transport and clouds particles properties though home and abroad. Main work is divided into three steps:first, established pulsed laser transmission model based on Monte Carlo method. Then, established atmospheric model containing cloudscape with geometry and optical properties. The last, analysed the spatial-temporal properties of the detector receiving backscatter signal when the plused laser active detection in the atmosphere containing cloudscape. Main work including:(1) Research on pulsed laser transmission model based on Monte Carlo method.Established pulsed laser emission model. Simulation of laser pulses propagation process in dispersion medium based on Monte Carlo method. Focuses on the laser emission model and the probability models in the propagation process. Through the theoretical formula and light transfer rules to verify the accurate model of Mento Carlo method.(2) Atmospheric model containing cloudscape generation and optical properties characterization.Simulating the cloudscape surface geometry through iterations and smoothing coefficient which can control the height distribution of cloudscape surface by Diamond-Square algorithm. Solving the number density Gauss distribution in height direction and different wavelength optical parameters of cloudscape based on the standard atmospheric profile data, the size distribution model of cloudscape drops, Mie scattering theory. By comparison of the data with the relevant reference, demonstrating the feasibility of this process, and generating three dimensional cloudscape with geometry and optical properties.(3) Research on the spatial-temporal properties of plused laser propagation in the atmospheric field containing cloudscape.Analysis the influence of plused laser spatial-temporal properties on cloud field parameters such as cloud modes, cloud thickness, incident wavelength, anisotropic degrees of particles scattering, target surface emissivity. Analysis the features of backscatter signal spatial-temporal segregation and scattering links by different cloudscape models. There has been a small probability detection event in the simulation of backscatter signal by Mento Carlo method. To solve this problem presents new solution, and analysis the influence of backscattered signal spatial-temporal properties on detection parameters such as detection area, detection viewing angle, detection zenith angle.