局域网的无线光互连技术的研究与实现

【作者】 彭小娟；

【导师】 陈晓天；

【作者基本信息】 广东工业大学 ， 信号与信息处理， 2004， 硕士

【摘要】 本论文针对信息时代电信业务朝带宽化发展的趋势，提出了采用基于大气介质信道的激光宽带通信技术，为带宽通信提供了一条新的途径。 论文首先探讨了无线光通信的基本理论、应用及发展。无线光通信以其投资小、传输容量大、安装迅速、电磁兼容性好等优点成为新近活跃的一种通信方式。为了保证无线光通信的质量，本论文还深入分析了大气衰减效应和大气湍流效应对激光传输的影响。然后给出了一种基于以太网的光无线组网的具体方案和该通信系统的结构、功能模块和原理图。最后，本论文具体分析了光无线局域网系统各个组成部分，主要是光电转换器和光收发器的工作原理，并进行了实验制作。初步实现了光无线局域网。 论文提出了利用激光组建无线局域网，给出了光无线组网的具体方案，方便地实现了廉价而高速的局域网内微机的互连；论文工作中设计并制作了带有自动功率控制(APC)、无光报警、自动增益控制和温度补偿功能的光收发器，使激光二极管能够不受环境温度的影响发出稳定的光功率，提高了系统的性能；设计的系统采用650nm的可见光作为工作波长，省去了价格昂贵的红外望远镜对准系统，降低了系统的成本；在光无线局域网中利用现有的成熟有线局域网协议和技术，从而保证了系统的实用性及改善了系统的性价比。 光无线组网技术具有较好的实用性和市场价值，是现有无线组网技术的补充和发展。更多还原

【Abstract】 In the paper, a project of optical wireless LAN based on Ethernet is presented. By analyzing the system’s structure and each part of the function components, the paper illustrates in detail all kinds of communication theories and protocols that are fundamental for the system’s operation. Especially, the paper makes a deep research on some crucial technologies by which a new kind of wireless LAN becomes hopeful, competitive and above all, practical. The wireless LAN in the paper is made up of three sets of PC, hub and optical transceiver. PCs and optical transceiver are used to form the LAN and control data communication. The hub is responsible for establishing the link.The paper contains two different fields of network communication and optical communication. And all kinds of theories and technologies related to optical wireless LAN based on Ethernet. Firstly, the basic theories and applications of wireless optical communications are discussed in the paper. Laser atmospheric communication has the characteristics of low investment, large capacity, quick setting, and fine electromagnetism compatibility. It is a newly active means to build up network. To ensuring the transmitting quality, the influences of atmospheric attenuation and turbulence to laser transmission is analyzed in the paper. Lastly, the working theory of encoder, decoder and optical transceiver of the optical wireless LAN are analyzed. The experiments about the system are done in the paper and basically realize the wireless optical LAN.The main originalities and latest technologies used in the operation of the system are as following: 1. Connecting computers through laser in a LAN wirelessly, high speedily and cheaply by using the technology of optical wireless communication. 2. Designing the APC and ATC in the optical transceiver. 3. Using wavelength near 650nm, and making the system to leave out expensive telescope system. 4. Taking good advantages of the fledged LAN communication protocols and technologies to achieve a new method that has a high rate of capability to costing in building a wireless LAN.Optical wireless LAN based on Ethernet is very practical and will be the competitive in market application. It is a useful supplement to the LAN now and will be more and more important in the future communication network.更多还原