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1.
Gerstel  O. 《IEEE network》1996,10(6):14-20
This article discusses the possible applications for optical networks based on wavelength division multiplexing and how they compete and complement current high-speed networks (SONET, ATM). We first outline the best-case scenario for this technology and describe the spectrum of proposed optical networks (WDM links, passive optical access networks, broadcast-and-select networks, and wavelength routing networks). Then we focus on wavelength routing networks and describe their advantages and disadvantages relative to other competing alternatives for very-high-speed networks. Finally, we analyze the different markets for such networks in the telco and data communications arena  相似文献   

2.
A general passivity criterion for digital networks is introduced. Digital networks that meet this criterion form a stable and useful class of networks. The networks in this class have properties similar to passive analog networks. These networks are all stable, and some networks, including all linear networks, are shown to have restricted gain. The gain restriction can be used to design filters that are insensitive to changes in multiplier values at frequencies of maximum gain. Emerging directly from this criterion is a procedure for interconnecting simple networks to form a complex passive network. These networks remain stable after the introduction of rounding following multiplications so that these networks do not exhibit limit cycle oscillations  相似文献   

3.
光学全交叉网络的快速控制需要在全混洗网络与光学全交叉网络间进行相互转换,本文分别给出了光学全交叉网络转换成全混洗网络及全混洗网络转换成光学全交叉网络时结点、链路、输入端口、输出端口的映射规则,并用电子学进行快速实现。  相似文献   

4.
Progress in supervised neural networks   总被引:5,自引:0,他引:5  
Theoretical results concerning the capabilities and limitations of various neural network models are summarized, and some of their extensions are discussed. The network models considered are divided into two basic categories: static networks and dynamic networks. Unlike static networks, dynamic networks have memory. They fall into three groups: networks with feedforward dynamics, networks with output feedback, and networks with state feedback, which are emphasized in this work. Most of the networks discussed are trained using supervised learning  相似文献   

5.
Multiwavelength lightwave networks for computer communication   总被引:1,自引:0,他引:1  
The different approaches being considered to build high-capacity lightwave networks are described. Two kinds of lightwave network architectures are examined: broadcast-and-select networks and wavelength-routing networks. A comparison of the two shows that broadcast-and-select networks may be more suitable for local area networks (LANs) and metropolitan area networks (MANs), while wavelength-routing networks are suitable for wide area networks (WANs). The overall network may then be a combination of broadcast subnets interconnected by a point-to-point wavelength-routing network  相似文献   

6.
移动网与固定网存在大量共同的技术,因此,在讨论移动网的核心网和业务网时,可以与固网结合起来讨论.在全IP移动网的核心网方面,文章认为:由于采用了不面向连接的工作方式,简化了信令,克服了节点设备复杂化以及与传送网技术的发展相匹配,IP网将是全IP移动网的核心网.在全IP移动网的业务网方面,文章认为:因为电路交换网与分组交换网网络特性的差别,全IP移动网的业务网设计应当有别于目前简单的映射电路交换网的业务网设计,应该符合分组交换网网络特性,因此,从商业模型出发,对业务网与承载网相分离的说法需要重新审视.  相似文献   

7.
FBG传感网络技术研究   总被引:11,自引:2,他引:9  
系统分析和总结了现有 FBG传感技术的复用结构和系统性能 ,并依据复用方式的频域、时域和空间特性 ,从网络拓扑结构的角度 ,提出把 FBG传感网络划分为波分复用网络、时分复用网络、空分复用网络、频分复用网络和混合复用网络 ,在此基础上比较了各种复用方式的优缺点 ,并针对网络实用化开发提出了自己的观点 ,从而为 FBO传感网络拓扑结构及性能的研究提供了参考。  相似文献   

8.
陈帅  廖晓纬 《信息技术》2006,30(12):11-13
无线传感器网络是复杂的无线网络。无线传感器网络拥有大量的网络节点。网络节点是无线传感器网络的基础。为了研究复杂的无线传感器网络,采用了神经元描述了WSN的网络节点,用神经元模型表示了无线传感器网络。给出了无线待感器网络节点的神经元模型和无线传感器网络的神经网络模型,并将神经网络应用于无线传感器网络的数据融合应用。结果表明,基于神经网络的无线传感器网络研究可以使得复杂研究变得简单,利于开展WSN的深入研究。  相似文献   

9.
论三网融合     
讨论了电话网、计算机网、有线电视网三种网络的优势与不足,并提出实现宽带多媒体综合服务网的最佳途径:将有线电视网由单向广播式改造为双向交互式网络,进一步从技术和国家政策上讨论这个途径的可行性以及其社会意义。  相似文献   

10.
本文在电网络理论的基础上,提出了一种分析计算大规模电力系统区域网的方法,文中首先应用网络分块结点抑制法推导出区域网等效结点电压方程式。然后,列举一个小规模的网络来说明应用这种方法计算的过程。这种方法适用于大规模电力系统区域网的计算.它可以减少计算工作量,提高计算速度。  相似文献   

11.
介绍了无线传感器网络中一种实用性很强的线性无线传感器网络,分析了线性无线传感器网络相比较一般无线传感器网络的优势以及研究中的一些难题,并从实际应用的角度分析了线性无线传感器网络的研究方向。  相似文献   

12.
The following classes of connecting networks, based on their combinatorial properties, have been previously defined: networks nonblocking in the strict sense, networks nonblocking in the wide sense, rearrangeable networks, and blocking networks. To these the authors add the class of repackable networks, i.e., networks in which blocking can be avoided by using call repacking control algorithms. The conditions under which a three-stage Clos network is repackable are formulated and proved. The numbers of middle-stage switches in all network classes are compared, and the differences between repackable and rearrangeable networks are discussed  相似文献   

13.
无线Ad-hoc网络及其关键技术   总被引:3,自引:0,他引:3  
王珍   《电信科学》2003,19(4):10-13
本在介绍了无线Ad-hoc网络发展情况的基础上,分析了其面临的挑战及相应的关键技术,并对蜂窝网与Ad-hoc网络的结合及无线Ad-hoc网络中无线资源管理进行探讨。  相似文献   

14.
随着对复杂网络的深入研究,现实生活中越来越多的网络被证明具有复杂网络的特性,如小世界特性,无标度特性和高聚类系数等.本文介绍了九种现实网络所具有的复杂网络特性,并介绍了权重网络和空间网络的基本概念,它们更多的考虑了现实网络的特性,并能更好的模拟实际网络.  相似文献   

15.
Computer and data networks are the mechanism by which information systems are interconnected. The underlying technology and the principles of design for the architectures of such networks are still limited but the demands placed upon them are of continually increasing sophistication. The author reviews the ways in which a classification of networks can be determined, thereby providing a perspective for the designers of modern communication networks. It is the classification of networks (based upon wide-area networks, metropolitan area networks and local-area networks) which causes great confusion and so he sets out to explain how the spirit of classification should be used and not necessarily the law in order to appreciate the characteristics of the various types of network  相似文献   

16.
GSM/GPRS网络向WCDMA网络的演进   总被引:1,自引:0,他引:1  
国内现阶段的2G/2.5G网络已经越来越不能满足发展的需求,WCDMA作为第三代移动通信一种比较成熟的标准,被越来越多的人接受.如何从现有的GSM/GPRS网络向WCDMA网络平稳地过渡,如何尽量减少因新建网络带来的巨额成本,是每一个即将拿到3G牌照的运营商必须仔细考虑的问题.  相似文献   

17.
光学榕树网络与全混洗网络之间的转换及实现   总被引:4,自引:1,他引:3  
光学榕树网络的快速控制需要在全混洗网络和光学植树网络间进行快速的相互转换.分别给出了光学榕树网络转换成全混洗网络及全混洗网络转换成光学植树网络时结点、链路、输入端口、输出端口的映射规则,并用电子学进行快速实现.  相似文献   

18.
Future wireless networks are expected to consist of different types of wireless networks such as code division multiple access (CDMA) networks and public wireless local area networks (WLANs). The integrated network will require vertical handoffs between different networks. In this letter, we propose vertical hard- and soft-handoff algorithms and evaluate their performance in commercial wireless networks.  相似文献   

19.
A plethora of metropolitan area wavelength-division multiplexing networks have been proposed and examined in recent years with the aim to alleviate the bandwidth bottleneck between increasingly higher-speed local/access networks and high-speed backbone networks. Many of the considered metropolitan area networks use the arrayed waveguide grating as an optical building block. As we review in this article, in ring, interconnected ring, and meshed metro WDM networks, the AWG is typically used to realize wavelength multiplexers, demultiplexers, or optical add-drop multiplexers without capitalizing on spatial wavelength reuse. By using the AWG as a wavelength router, highly efficient star metro WDM networks can be realized due to extensive spatial wavelength reuse. We give an overview of star metro WDM networks that are able to meet modular upgradability, transparency, flexibility, efficiency, reliability, and protection requirements of future metro networks. AWG-based star networks also enable an evolution path of ring networks toward highly efficient and fault-tolerant hybrid star-ring metro network solutions.  相似文献   

20.
一些功能不同的双口网络适当地连接在一起会实现某种特定的功能.双口网络间的连接方式有:串联、并联、串-并联、并-串联和级联.除级联方式外,其它互连方式都存在有效互连的问题,只有在有效连接的情况下,讨论双口网络的参数矩阵与各分双口网络参数矩阵的关系才有意义.以双口网络的串联连接为例,证明了双口网络有效互连与端口有效性检查互为充要条件的结论,并给出了当互连的双口网络不满足有效连接判据时如何实现有效连接.这对双口网络互连的教学具有一定的帮助.  相似文献   

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