波分复用技术及其应用现状与发展前景

本文简单介绍了几种复用技术,并着重介绍波分复用技术及其优点,以及波分复用技术的应用现状与发展前景.     

浅析波分复用技术在电信本地网中的应用

本文在现代光通信的基础上,主要对DWDM技术的基本原理、关键技术、特点和影响因素做一个全面的论述。同时结合实际的工程应用,进一步论证了这种技术的广泛应用前景,最后论述了下一代密集波分复用（DWDM）系统的发展趋势和面临的问题。     

光网络中的分插复用技术

随着通信技术的发展,对全光网络的发展需要越来越迫切。光分插复用技术是实现全光网络的关键技术之一。重点介绍了光网络中分插复用技术的基本原理、具体实现方案和结构组成,并结合其研究进展简要分析了光网络中分插复用技术的发展趋势和应用前景。     

基于波分复用技术的光纤甲烷传感系统研究

应用波分复用技术,DMF(数字匹配滤波器)和自组织网络可以对甲烷气体浓度进行实时检测,并提出了一种安全型光纤甲烷气体传感器测量系统.系统采用1630 nm波段的SLED作为入射光源,利用甲烷在此处波段的低损耗窗口的吸收特性,使用提高波长检测精度的DMF对微弱信号进行处理以及对数据进行在线处理的自组织网络,使得系统的最小检测量为146 mg/m3.实验研究表明,系统的稳定性和准确度仍有提高的空间,可以实现远程监控.     

波分复用技术在广电网络扩容改造中的应用分析

近年来,随着我国光纤通信技术的不断发展以及网络规模的日益扩大,广电网络运营商的基础网络资源受到了越来越大的挑战,在此背景之下,要想实现广电网络的持续稳定发展,扩容改造是最重要最关键的出路。波分复用技术是一种新型的技术,因其所具有的特点与优势,目前已在通信网络中得到了较为广泛的应用。鉴于此,本文拟从波分复用技术概述、波分复用的关键技术以及波分复用技术在广电网络扩容改造中的应用等几个方面来进行分析与阐述,以期加深对这一问题的认识与理解程度。     

非零色散位移大有效面积光纤在高容量密集波分复用系统中的应用

由于英特网和各种新兴服务业的推动,全球通讯容量正在经历快速增长,并促使光纤技术达到更大的容量,更高的可靠性和更经济的解决方案。掺铒光纤放大器(EDFA)和密集波分复用(DWDM)技术已相当成熟,并已被证明能成功地满足未来容量的需求。与此同时,技术的进步也降低高容量系统的成本,在过去40年,传输容量已增长了4个数量级,而每线路成本也已减少了一万多倍。     

全光通信网及其发展现状

全光网是未来宽带网的发展目标,它是针对目前通信网中所存在的电子瓶颈效应而提出的。文中首先介绍了全光网的概念及其网络结构,全光网的优点以及全光网可提供的业务,然后介绍了全光通信网的关键技术及其目前的进展状况。     

密集波分复用技术在广电视频专网电路项目中的应用

笔者通过分析密集波分复用(DenseWavelengthDivisionMultiplexing)技术在广电网络视频专网电路租用项目上的实际应用,展示了密集波分复用技术具有光传输、灵活的信号处理、大带宽容量充足等优点。密集波分技术涵盖了光层和电层两层网络,其技术继承了SDH和WDM的双重优势,关键技术特征体现为:多种客户信号封装和透明传输;大颗粒的带宽复用、交叉和配置;强大的开销和维护管理能力;增强了组网和保护能力。     

波分复用分布式FBG传感网络

提出并实现了一种可满足工程实用要求的波分复用光纤光栅传感网络解决方案,系统通过可调谐光纤F P滤波器的连续扫描实现波长信号的解调,该传感系统扫描带宽50nm,单点工作带宽5nm,对一般应用系统每根单纤可设20～30个点,系统最高扫描频率200Hz,分辨力5pm(约5×10-6或0.5℃)。     

WDM star single-hop network reusing wavelengths

An efficient scheme of wavelength reuse is presented for solving the capacity limitation of WDM star single-hop networks by limited wavelengths. According to this scheme, the nodes supported by the network can be at least doubled under limited wavelength numbers. Under the same number of nodes, the delay of network can be greatly lowered, the throughput of the network can be increased 1-3 times, and the properties of the network can be efficiently improved.     

Routing and wavelength assignment for hypercube in array-based WDM optical networks

Hypercube is one of the most versatile and efficient communication patterns shared by a large number of computational problems. As the number of edges in hypercube grows logarithmically with the size of networks, the complexity of network topologies can be significantly reduced to realize hypercube in optical networks by taking advantage of the parallel transmission characteristic of optical fibers. In this paper, we study the routing and wavelength assignment for realizing hypercube on WDM optical networks including linear arrays and rings with the consideration of communication directions. Specifically, we analyze this problem for both bidirectional and unidirectional hypercubes. For each case, we identify a lower bound on the number of wavelengths required, and design the embedding scheme and wavelength assignment algorithm that uses a provably near-optimal number of wavelengths. In addition, we extend the results to meshes and tori. By our embedding schemes, many algorithms, originally designed based on hypercubes, can be applied to optical networks, and the wavelength requirements can be easily derived using our obtained results.     

On the joint link dimensioning and routing metric assignment problem for reliable WDM networks

In this paper, we tackle the joint link dimensioning and routing metric assignment problem for reliable wavelength division multiplexing (WDM) networks. This design problem consists to find the number of wavelength channels on each link and the routing metrics (considering shortest-path routing) that ensure the routing of all virtual wavelength paths (VWPs) and the successful rerouting of the reliable VWPs for all failure scenarios of interest to the network planner. A mixed integer mathematical programming model is proposed for the problem. The model is adapted for the single link failure scenarios. Since the problem is NP-hard, we propose a tabu search algorithm to obtain good approximate solutions for real-size instances of the problem. Finally, a lower bound is proposed and numerical results are presented and analyzed.     

A global approach for designing reliable WDM networks and grooming the traffic

In this paper, we address the global problem of designing reliable wavelength division multiplexing (WDM) networks including the traffic grooming. This global problem consists in finding the number of optical fibers between each pair of optical nodes, finding the configuration of each node with respect to transponders, finding the virtual topology (i.e., the set of lightpaths), routing the lightpaths, grooming the traffic (i.e, grouping the connections and routing them over the lightpaths) and, finally, assigning wavelengths to the lightpaths. Instead of partitioning the problem into subproblems and solving them successively, we propose a mathematical programming model that addresses it as a whole. Numerical results are presented and analyzed.     

WDM全光网络中的路由及波长分配

在全光网络中,光信号在全光域内传输,避免了光-电转换带来的延迟,因此,全光网支持高数据率传输并提供巨大的网络容量。WDM(波分多路复用)技术的采用使得高速光传输线路与低速终端处理设备之间能够相互兼容。论文探讨了WDM全光网中的路由及波长分配问题,对各种常用算法进行了详细的分析,并提出了对一种新型的用于WDM网络上的实时组播请求的分布式RWA算法进行改进的意见。     

WDM光传送网中基于链路状态等级的动态路由与波长分配算法

提出了两种基于链路状态分级的路由与波长分配算法．分别为链路等级优先的动态路由与波长分配算法（LFLS-DRAW）和满足等级要求的动态路由与波长分配算法（RLSDRAW）算法．理论分析表明，基于链路状态分级的路由与波长分配算法的计算复杂度与同类算法相当，且与其它算法相比具有一定的优越性．仿真结果表明．基于链路状态分级的路由与波长分．配算法在计算时间和平均路由跳数相近的情况下．所选择路径的路由状态等级较高．具有较强的负载均衡能力，可以有效降低网络的拥塞概率．     

The adoption and diffusion of e-commerce in developing countries: The case of an NGO in Jordan

The case study in this research involves a nongovernmental organization (NGO) in Jordan in the Middle East, which attempted to utilize electronic commerce (EC) to streamline its business processes and information flow to businesses in Jordan and to other international businesses interested in the Jordanian market. The NGO managed to achieve these tasks expeditiously, and its EC initiative assisted in adding an effective digital parallel to existing systems and processes in this NGO. The NGO is directly involved in the e-government initiative empowered by H.M. King Abdullah II. At this end, with this royal support, the NGO successfully adopted EC. During the adoption and implementation process, the organization encountered numerous difficulties, as detailed in this research. However, the full success of EC was hampered by other factors. Initially, other governmental entities related indirectly to this NGO were not EC-ready. Second, although Web site utilization was growing in this NGO, most member merchants were reluctant to switch to the online arena and to abandon traditional practices in obtaining information and resources from this NGO. However, the NGO is aware of these concerns and envisages resolving such hurdles in its medium- to long-term projections. © 2007 Wiley Periodicals, Inc.