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1.
以无线ATM技术为基础提出了采用信元中继作为无线传输基础的PCN的结构,即利用ATM交换网络来互联PCN小区,ATM信元作为网络的有线和无线部分中协议处理和交换的基本单元,然后逐层分析了关键技术.  相似文献   

2.
一种用于无线ATM的Turbo码的研究   总被引:1,自引:0,他引:1  
无线ATM能通过标准的ATM网络应用接口,为多种移动终端提供综合宽带业务的传输和交换。研究了适用于无线ATM的Turbo码,对Turbo码与卷积码的性能进行了比较,并且对不同编码效率下Turbo码的纠错能力进行了仿真研究。  相似文献   

3.
现代军事战争,信息的传输不但数量激增,而且信息的类型也趋于多样化。为此,设计了团、营、连三级战术C3I数据传输网络体系,该网络以直升机和卫星作为中继节点,团(旅)指挥中心以ATM虚拟局域网实现综合业务的交换传输,从而实现了多媒体流的传输。该网络包括了ATM、以太网和无线局域网。通过理论仿真分析,此网络体系结构满足了现代军事战争的要求。  相似文献   

4.
据《Signal》1992年5月号报道,SEL Alcatel公司研制的保密战术网现正式交给军方使用。该网用于旅或集团军,由两种节点组成:第一种是数字交换系统的访问切点,它能给网络用户提供视距或光纤链接;第二种是干线节点,它给访问节点到终点提供通路。另外单路无线访问可在有线网和无线网之间提供链接。交付的网络设备包括能作为干线、访问和本地三种交换设  相似文献   

5.
介绍了军事无线通信网络的重要形式——战术互联网;分析了无线IP技术和无线ATM技术;讨论了无线网络技术与战术互联网构筑的密切关系;最后举例说明了无线网络技术应用于战术网的广阔前景和所面临的主要技术挑战。  相似文献   

6.
ATM交换技术     
ATM交换系统包括两部分:交换网络和控制部分。交换网络部分包括线路接口和交换结构,具有处理用户平面信元的功能;控制部分具有控制平面信元处理和管理平面信元处理的功能。此外,ATM交换系统还完成流量管理与控制功能,以保证用户的业务质量要求。下面,我们给出ATM交换系统的功能框图。  相似文献   

7.
现代军事战争,信息的传输不但数量激增,而且信息的类型也趋于多样化。为此,设计了团、营、加三级战术C∧3I数据传输网络体系,该网络以直升机和卫星作为中继节点,团(旅)指挥中心以ATM虚拟局域网实现综合业务的交换传输,从而实现了多媒体流的传输。该网络包括了ATM、以太网和无线局域网。通过理论仿真分析,此网络体系结构满足了现代军事战争的要求。  相似文献   

8.
一个移动IP组播原型结合了无线异步传输模式标签交换,它的核心建立在组播的体系结构上。MCOM创建了独立于成员所属网络的多核心的第二层多点交换树,并通过Internet第三层多点交换路由来互相连接。Internet与无线ATM边界的网关把IP包转换成ATM信元,但需要改变ATM阻塞传送能力解决信元交叉问题。另外,讨论了动态组管理、组播重选路由和可靠组播与现在的各种网络协议的关系。  相似文献   

9.
无线ATM网络作为PCN同B—ISDN/ATM互联的关键技术具有很强的生命力.本文在介绍无线ATM性能特点的同时,总结了目前无线ATM研究领域的研究热点,并简要地探讨了这些研究课题的解决方案和研究前景.  相似文献   

10.
刘树东  贾世楼 《无线电工程》2001,31(10):52-55,61
该文介绍了移动多媒体通信中无线ATM的基本概念和研究现状,包括无线ATM概念、无线ATM网络分层模型和传输结构。讨论了无线ATM网络中的接入控制技术和差错控制技术。  相似文献   

11.
In this article we focus on the transport and switching part of third-generation mobile access networks and outline some important aspects of applying ATM in these networks. In particular, we argue that in order for the mobile access network to support low-bit-rate delay-sensitive traffic consisting of short packets, the standardization of a new ATM adaptation layer, AAL2, and associated signaling protocol has been necessary. The AAL2 protocol has been designed to support low-bit-rate delay-sensitive services (typically compressed voice) where other adaptation layers fail to deliver the required QoS and maintain efficient resource utilization at the same time. Furthermore, in order to provide mobility and soft handover support in W-CDMA-based mobile networks such as UMTS or IMT-2000, there is also a strong demand for fast connection establishment and release. Therefore, when designing ATM-based cellular access networks some specific architectural and traffic management issues need to be addressed  相似文献   

12.
Wireless ATM networks: technology status and future directions   总被引:3,自引:0,他引:3  
The concept of “wireless ATM” (WATM), first proposed in 1992, is now being actively considered as a potential framework for new-generation wireless communication networks capable of supporting integrated, quality-of service (QoS) based multimedia services. In this review paper, we outline the technological rationale for wireless ATM, present a system-level architecture, and discuss key design issues for both mobile ATM switching infrastructure and radio access subsystems. The WATM radio access layer issues covered in this paper include: spectrum allocation; spectrum etiquette; modem technology; and medium access/data link control (MAC/DLC) protocols. Mobile ATM aspects such as ATM signaling extensions for handoff control, location management, and mobile QoS control are discussed. A summary of current wireless/mobile ATM technology development and standardization status is given, including an outline of our WATMnet prototype. The paper concludes with a discussion of future directions for wireless ATM technology such as Internet protocol (IP) integration and mobile multimedia terminals/applications  相似文献   

13.
将传统的局域网接入ATM网,利用ATM网进行互通,不仅可以提高局域网互通遥性能,而且对于保护用户已有的诉发展和也非常有利。本文提出了将局域网接入ATM网,利用AT 进行互通的一种方案,地方案的具体实施进行了研究。  相似文献   

14.
An ATM transit switch is proposed based on direct sequence optical code division multiple access technique. No buffering is necessary to facilitate the switching. Code conversion is used instead to emulate the switching function. The switch not only provides asynchronous access to the users but also has a limited capability of dynamic bandwidth allocation. It is free from timing jitters and switching delay is significantly reduced. A look‐up table is employed in the switching and updated through network management functions. The switch provides a new approach to asynchronous cross‐connection in the ATM core network. The performance of the new switch is evaluated by a set of prime codes and modified prime codes. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

15.
Future broadband satellite networks for multimedia will be seamlessly integrated into terrestrial broadband networks which often use asynchronous transfer mode (ATM) and recently also the less complex multi protocol label switching (MPLS) technique as transmission and switching protocol. In light of this, future broadband satellite networks may adopt the ATM transmission scheme and implement ATM or ATM‐like switches on board the satellites. However, as compared to communication in fixed networks, satellite communication is characterized by special constraints (e.g. signal delay, channel quality, dynamic network topology) that require novel ATM‐based communication technology for satellite systems. This paper presents results from the ATM‐Sat project that aims to complete this technically challenging and important R&D task in the cooperation between DLR, Fraunhofer Gesellschaft and Tesat‐Spacecom. In brief the following aspects have been addressed in the ATM‐Sat project:
  • development of the concept and communication technology for a multimedia satellite system with,
    • non‐geostationary orbit (NGSO) satellites;
    • inter satellite links (ISLs);
    • on‐board ATM switching;
    • fixed and mobile terminals;
  • verification of the developed communication technology with a demonstrator.
In particular the ATM‐Sat R&D tasks cover the system and protocol architecture, on‐board processing, ISL routing, up/downlink and on board ATM resource management (including medium access control), error control, IP over satellite‐ATM, and active intelligent antennas. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

16.
This paper sketches the requirements and possibilities of wireless ATM in local area networks. Because of the wide range of services supported by ATM networks, ATM technology is expected to become the dominant networking technology in the medium term for both public infrastructure networks and for local area networks. ATM infrastructure can support all types of services, from time-sensitive voice communications and desk-top multi-media conferencing, to bursty transaction processing and LAN traffic. Extending the ATM infrastructure with a wireless access mechanism meets the needs of those users and customers that want a unified, end-to-end networking infrastructure with high-performance, consistent service characteristics. The paper introduces ATM concepts, discusses the requirements for wireless ATM, in particular for data link control and radio functions. It closes with some notes on development of wireless ATM research systems standardization and spectrum allocations.  相似文献   

17.
虚拟局域网     
黄可  孙海荣 《电信科学》1995,11(3):53-57
虚拟局域网是网络用户独立于网络物理配置和位置的一个逻辑组合,综结合了网络交换和管理功能,使网络根据用户需要分割成多个逻辑网,管理员对分布于各个网段的用户视作在同一逻辑网中进行管理,在网络性能、保护用户投资及向ATM过渡方面具有很好的性能。本文对虚拟局域网技术进行综述。  相似文献   

18.
Over the past several years, a number of new satellite systems have been proposed to provide high-speed Internet and multimedia services to businesses and home users. These proposals have been driven by the desire of network operators to reach end users that do not have cost effective access to other alternatives such as fiber, DSL, and cable, and by the availability of new spectrum (Ka-band) for use by new satellite services. The proposed systems generally employ multiple high-power spot beams, an onboard fast packet switch, and a demand-assigned multiple access scheme to provision IP-based services. In this article we concentrate on a geosynchronous satellite system where packet transport and switching within the satellite system are based on ATM. We describe an IP/ATM interworking and IP routing architecture that is driven by three main requirements: (1) the ability to support ATM SVCs between hundreds of thousands of satellite terminals by a single ATM switch located onboard; (2) a scalable IP routing architecture that does not result in large volumes of routing traffic to be transported over the satellite; and (3) the ability to segment the satellite terminals for routing and administrative control by ISPs and enterprise networks  相似文献   

19.
Emerging wireless broadband networks   总被引:1,自引:0,他引:1  
The rapid evolution of mobile wireless access networks toward multimedia support with QoS provision forces the development of advanced wireless broadband systems with high reliability and high data rate. To achieve this goal, new system design concepts with increased system capacity will be required. In that context, ATM is becoming a major infrastructure, receiving a lot of attention for telecommunication systems since ATM networks can most effectively support wireless access systems. Wireless ATM systems have low transmission cost, flexible functionality, mobile ATM protocol, and radio access layer protocols. This article overviews the various wireless broadband systems studied at 5, 19.37, 40, and 60 GHz by European Union funded projects within the ACTS program. Moreover, related standardization activities and network evolution are also addressed  相似文献   

20.
A wireless ATM system consists of a core network infrastructure that provides mobility support to end terminals and a wireless access link. This article outlines two schemes for supporting mobility of IP terminals in this network. In the first scheme, location management and handoff support is integrated within the ATM signaling and control framework (“mobile ATM”), and mobility is transparently supported at the IP layer by mobile ATM underneath. In the second approach, the IP protocol stack is directly executed on ATM switches (without an intermediate ATM signaling stack) using an IP switching technique called IPSOFACTO (IP Switching Over Fast ATM Cell Transport), and terminal mobility is supported via mobile IP  相似文献   

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