Research On Seawater Channel Of Blue-green Laser Communication

Seawater channel of blue-green laser communication is a complex random channel, perfect, vertical channel attenuation model has great significance and reference value for the design and implementation of blue-green laser uplink/downlink communication systems. This paper focus on the absorption/scattering characteristics of channel attenuation material and vertical attenuation distribution of the thermocline, and Monte Carlo simulation and theoretical analysis are adopted for modeling the up/down channel transmission under different scenarios respectively.Firstly, for the Yellow Sea 340-360N, 1220-1240E range, this paper focus on the chlorophyll, yellow substance and suspended sand concentration of different seasons, establishes Mie scattering and absorption vertical distribution model based on the concentration. Secondly, the seasonal thermocline attenuation characteristics are analyzed in detail, the new gene expression programming (GEP) is proposed for the automatic modeling of vertical distribution of the thermocline attenuation coefficient in different seasons, and compared with traditional curve fitting algorithm: cftool and genetic algorithm. Finally, based on MATLAB simulation platform, MC simulations for the blue-green laser up/down transmission under different scenarios are implemented, then the received spots are analyzed, and theoretical analyses prove the accuracy of the simulation.