【作者】 刘彬；

【导师】 孙军强；

【作者基本信息】 华中科技大学 ， 物理电子学， 2004， 硕士

【摘要】 在DWDM光网络中,光学串扰对于通信性能有很大的影响,已成为光网络设计中最重要考虑因素之一,也是目前国内外广泛研究的焦点。本论文分析了DWDM系统中关键技术OXC,并详细分析了光交换网络中带内串扰消除方法,详细内容包括以下几部分:简要介绍了全光网络当前的发展,DWDM技术和OXC在光传输网中的功能、应用、发展趋势和关键技术。同时对DWDM光网络中串扰作了简要分析,并指出带内串扰作为光通信领域发展的重要制约因素,成为我们项目研究重点。介绍各种不同类型的光互连交换网络(光交换矩阵),包括Crossbar光交换网络、Omega互连网络、Crossover互连、Banyan互连网络和Comega互连网络,并对各个交换网络特点进行了分析和讨论,详细介绍了光互连交换网络的矩阵理论,并以Omega和Crossover为例,分析了交换矩阵理论和特征方程,最后对不同光互连交换网络之间的拓扑等价性进行了分析。详细分析了扩展的Benes(DB)型光交换结构串扰特性,重点研究了一种改进扩展Benes结构(MDB)。从DB型光交换结构出发,提出了传输矩阵和结构矩阵的概念。通过本算法,选择合适光交换网络路由方式实现消除8×8光交换网络带内串扰,并把算法扩展到N×N DB结构。本算法完全消除MDB带内串扰,同时也可以大大降低一般DB光交换结构的带内串扰。在Benes(DB)光交换结构基础上,在特定输入波长条件下,减少光交换矩阵的ON-OFF器件可行性分析。开发了8×8光交换模块软件。介绍了软件的设计思想和原理,重点介绍了控制模块的实现,一是PC机将光开关的状态信息传递给单片机,另一部分是探测模块探测光信号,并把数据通过单片机控制模块显示出来。为了保证PC和控制系统的通信,指定了详细的通信控制协议。探讨性的讨论了光交叉连接(OXC)中全光波长转换器的使用。提出了共享波<WP=5>长转换器的OXC结构机制,研究了波长转换器个数以及波长转换器转换带宽对OXC阻塞的影响。并提出可以通过合理设置OXC中波长转换器个数和配置转换带宽,提高整个OXC的抗阻塞性能和降低系统成本。最后,对算法进行了仿真。更多还原

【Abstract】 In DWDM optical transport networks, optical crosstalk has great impacts on communication performance, and becomes one of the most important factors when designing optical network, which is also researched by many research institutions. In this thesis, OXC technique is analyzed, and a measure for eliminating intraband crosstalk in OXC is proposed in details. Major subjects in this thesis are discussed as follows:Development of optical networks is presented, and function, application, development trend and key technology in DWDM and OXC are introduced. Crosstalk in DWDM optical transport networks is analyzed, and intraband crosstalk is figure out to be a restrictive factor that affect optical communication, which also become the main point our project focus on. Diverse optical switching matrixes are presented, including Crossbar、Omega、Crossover、Banyan and so on. The features in different switching matrixes are discussed. Matrix theory is analyzed on the example of Crossover. Equivalence of topology in different switching matrixes is derived at last.Crosstalk characteristic in dilated Benes (DB) switching network, principally in a special architecture of modified dilated Benes (MDB) is investigated in this section. Based on the DB, an idea of studying routing through transmission matrix and structure matrix is put forward. Intraband crosstalk can be eliminated through routing optimized with this algorithm, then this algorithm is extended to N×N DB. Intraband crosstalk can be eliminated completely in MDB, and can also be eliminated greatly in DB with this algorithm.On the base of DB switching network, feasibility of reducing the number of ON-OFF switches is investigated in cases of special signal wavelength, such as all the wavelengths of input signals are equal. <WP=7>The software of “ 8×8 optical switching analyzer ” is developed. The development idea and theory is introduced, and the implementation of control module is present principally, which include two parts: one is communication between PC and optical switching module for transferring the states of optical switch; the other is to detect optical signal and send feedback to PC. Control protocol is put forward in order to assure the communication between PC and control system.An OXC Architectures with wavelength conversion capability is proposed, in which the number of wavelength converters (WCs) is optimized by means of WC sharing. The effectiveness of the number of WCs and the bandwidth of WC for blocking probability is individually investigated through simulation .It is concluded that blocking probability and cost of OXC can be improved by optimizing the number of WCs and the bandwidth of WC.更多还原