沙尘天气下近地面无线光通信的传输机理及特性研究

项目名称： 沙尘天气下近地面无线光通信的传输机理及特性研究

项目编号： No.61265003

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 王惠琴

作者单位： 兰州理工大学

项目金额： 49万元

中文摘要： 沙尘天气在西部地区全年约占70天左右。在这期间，沙尘暴造成的悬浮颗粒对激光产生散射和吸收，会严重影响近地面无线光通信的有效性和可靠性。为此，本课题拟研究激光信号在沙尘天气下的传输机理与特性。依据Mie理论，采用多次散射得到沙尘天气下的光强分布和光强起伏特性，建立单光束和多光束传输时光强的概率分布函数；建立沙尘天气下光MIMO的信道模型，并分析其性能，同时研究相关性对系统性能的影响；针对强度调制分别提出级联空时分组码、级联分层空时码和级联空时网格码的方案，并对其内外码的设计与选择、交织器的构造、联合检测-译码算法、迭代信道估计/译码/检测等关键技术进行研究；将信道估计、信道译码和空时检测三者合并，结合PPM调制信号的特点，提出一种迭代估计/译码/检测方案。 该项目取得的研究成果为抵御沙尘暴对光通信的影响提供新途径，并为实现大容量、高速率、远距离的光通信提供理论依据和有效手段。

中文关键词： 无线光通信；沙尘；多输入多输出；脉冲位置调制；空时编码

英文摘要： In northwest China, sand and dust storms occur frequently throughout the year about 70 days. During the period, the laser scattering and absorption resulted from suspended particles seriously affect the validity and reliability of wireless optical communication systems. Therefore, this project intends to conduct a research on the optical signal transmission mechanism and its characteristics in sand and dust weather. Based on Mie theory, the light intensity distribution and the light intensity fluctuation characteristics are analyzed by using the multiple scattering in sand and dust weather. The probability distribution functions of single-beam transmission/multi-beam transmission are established. The optical MIMO channel model in sand and dust weather is also established, with its performance analyzed and the effect of its correlation on system performance explored. We propose the Concatenated Space-Time Block code, Concatenated Layered Space-Time Code and Concatenated Space-Time Trellis Code schemes based on intensity modulation respectively. And the key technologies of the internal/external code design and choice, interleaver structure, joint detection-decoding algorithms, iterative channel estimation/decoding/detection algorithm are discussed. Finally, according to PPM modulated signal, an iterative channel e

英文关键词： wireless optical communication；sant and dust；multiple input multiple output；pulse position modulation；space time code