文档介绍：华中科技大学
硕士学位论文
蓝绿激光通信海水信道的研究
姓名:常方
申请学位级别:硕士
专业:通信与信息系统
指导教师:董燕
2011-02-23
华中科技大学硕士学位论文

摘要
蓝绿激光通信的海水信道是个比较复杂的信道。建立一个完善的四季海水信道
垂线衰减模型对蓝绿激光上行/下行通信系统的研究、设计和实现有着重要的理论意
义和价值。本文着重研究了海水信道中不同衰减物质的四季吸收、散射垂线分布特
性,分析了温跃层对衰减特性的影响,并分别对不同场景下的上/下行信道传输特性
进行 MC 仿真,并对仿真结果和理论推导进行了比较分析。
首先,在黄海 340-360N,1220-1240E 范围内,重点讨论了叶绿素、黄色物质和悬
浮沙粒的四季浓度分布,建立了基于介质质量浓度的四季吸收垂线分布模型以及四
季米氏散射垂线分布模型。其次,分析了季节性温跃层的存在对海水信道衰减特性
的影响,基于改进的基因表达式编程(GEP)实现了海水中温跃层内部衰减系数的
四季垂线分布模型的自动建模,并与传统的曲线拟合算法:MATLAB 曲线拟合工具
箱(cftool)、改进的遗传算法进行比较。最后,采用蒙特卡罗方法模拟了不同季节场
景下的蓝绿激光在海水和大气中的上下行传输,对接收到的光斑进行统计分析,通
过理论分析验证了仿真的准确性。

关键词:蓝绿激光通信;衰减系数建模;温跃层;GEP;上/下行信道;MC 仿真

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华中科技大学硕士学位论文

Abstract
Seawater channel of blue-green munication is plex random channel,
perfect, vertical channel attenuation model has great significance and reference value for
the design and implementation of blue-green laser uplink/munication
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, pared with traditional curve fitting algorithm: cftool and ic
algorithm. Finally, based on MATLAB simulation platform, MC simulations for the
blue-green laser up/down transmission under different scenarios are implemented, then the