共查询到20条相似文献,搜索用时 140 毫秒
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以太网无源光网络(EPON)和IEEE 802.16(WiMAX)的融合网络在固定移动混合接入网中被认为是很有前景的接入方式.文中提出了3种WiMAX无线网络与EPON网络系统融合架构,融合系统同时具有光网络的高带宽和无线网络的灵活性.为了在接入网中支持QoS,本文为融合结构提出了一种动态带宽分配算法(DBA)和调度机... 相似文献
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WiMAX应用潜力分析 总被引:1,自引:0,他引:1
文章分析了WiMAX在固定宽带无线接入场合和便携、移动通信场合的应用前景.文章认为:在固定宽带无线通信中,WiMAX会广泛应用于家庭用户、IP语音用户、传输承载用户和集团客户,为他们提供宽带无线接入;在便携、移动通信中,IEEE802.16即将集成到笔记本电脑和个人数字助理(PDA)等便携式电子设备中,实现在城域网范围内的可移动的宽带无线数据服务;用户需求加上WiMAX设备的批量上市及终端成本的下降,WiMAX的应用潜力巨大,市场将呈几何级增长. 相似文献
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Broadband wireless access 总被引:4,自引:0,他引:4
This article reviews the technologies and potential markets, applications, and architectures for broadband wireless access. The emergence of wireless communications for cellular systems is presented, together with its projected future evolution to mobile wideband systems. The field of broadband access systems, services, and network architectures is also covered, and then systems for broadband wireless communications for indoor local area networks and outdoor public fixed access networks are discussed. Broadband wireless access systems are emerging as a new and growing area of telecommunications, since the ability to provide access without extensive installation of copper or fiber infrastructures make wireless technology well suited for broadband services. Finally, some of the key enabling technologies, such as adaptive antennas and video compression, and the future architectural directions of broadband wireless networks are presented 相似文献
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Koon Hoo Teo Zhifeng Tao Jinyun Zhang 《Signal Processing Magazine, IEEE》2007,24(5):144-148
Mobile worldwide interoperability for microwave access (WiMAX) is a wireless standard that introduces orthogonal frequency division multiple access (OFDMA) and other key features to enable mobile broadband services at a vehicular speed of up to 120 km/h. WiMAX complements the and competes with wireless local area networks (WLANs) and the third generation (3G) wireless standards on coverage and data rate. More specifically, WiMAX supports a much larger coverage area than WLAN, does not require line of sight for a connection, and is significantly less costly compared to the current 3G cellular standards. Although the WiMAX standard supports both fixed and mobile broadband data services, the latter have a much larger market. Therefore, this article will briefly present the Mobile WiMAX standard, the technologies deployed for the air interface and the network, and the development of the standards to support mobile multihop relays in a WiMAX network. 相似文献
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WiMAX关键技术及网络结构探讨 总被引:2,自引:0,他引:2
朱蓉 《信息安全与通信保密》2010,(1):85-87
WiMAX支持非视距传播条件下的无线宽带接入,它致力于为无线网络提供低时延、高质量的语音和数据服务,正迅速发展并将在无线城域网中扮演重要角色。WiMAX技术因其定位于城域级的无线宽带接入,具有覆盖范围广、传输距离远、传输速率快等优势,在未来的无线宽带移动通信领域将会占有相当重要的主导地位。文中从WiMAX的基本特征、关键技术和网络结构及应用3个维度对WiMAX进行了分析与探讨。 相似文献
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从宽带无线接入与宽带移动通信技术的融合看B3G技术的发展趋势 总被引:1,自引:0,他引:1
本文总结与比较了3GPP长期演进技术、3GPP2空中接口演进技术、IEEE 802.16e WiMAX技术和IEEE 802.20 MBFDD/MBTDD技术的标准化进程、系统需求和核心技术.在此基础上,本文讨论了宽带无线接入技术和宽带移动通信技术的融合趋势,并探讨了超3G技术的发展方向. 相似文献
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WiMAX is the first cellular standard that employs OFDMA technology and provides true integrated services for both fixed and mobile broadband access. Among the many new technologies adopted in WiMAX, MIMO antenna technology plays an essential role in delivering fast, rich-content, mobile broadband service reliably over extended coverage areas. In this article we provide a survey on the state of art of MIMO technologies in current WiMAX standards with an emphasis on practical engineering considerations. Moreover, we also briefly discuss the ongoing MIMO technologies in the evolution toward the next-generation WiMAX network. 相似文献
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Walter Konhäuser 《Wireless Personal Communications》2006,37(3-4):243-259
The growth in mobile communication will accelerate over the next years. Today most of the mobile subscribers use cellular services only. But this will change in the near future towards broadband wireless access services like WiFi and WiMAX. This paper describes a fundamental overview of the broadband wireless access technologies and outlines the market view, major trends and introduces OFDM technologies. New developments for integration of broadband wireless access into the operators' infrastructure are also discussed. 相似文献
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Seamless integration of mobile WiMAX in 3GPP networks 总被引:2,自引:0,他引:2
As the wireless industry makes its way to the next generation of mobile systems, it is important to engineer solutions that enable seamless integration of emerging 4G access technologies within the currently deployed and/or evolved 2G/3G infrastructures. In this article we address a specific case of such a seamless integration, that of mobile WiMAX in evolved 3GPP networks. In this context we investigate the architecture and the key procedures that enable this integration, and we also introduce a novel handover mechanism that enables seamless mobility between mobile WiMAX and legacy 3GPP access, such as UTRAN or GERAN. The core characteristic of this novel handover mechanism is that mobile terminals do not need to support simultaneous transmission on both WiMAX and 3GPP accesses; therefore, it mitigates the RF coexistence issues that exist otherwise and improves handover performance. In addition, we provide a brief overview of mobile WiMAX and the evolved 3GPP network technologies, and we set the appropriate background material before presenting our proposed handover mechanism. Our main conclusion is that integrating mobile WiMAX in evolved 3GPP networks is a compelling approach for providing wireless broadband services, and mobility across WiMAX and 3GPP access can become seamless and efficient with no need for mobile terminals to support simultaneous transmission on both types of access. 相似文献
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WiMAX networks: from access to service platform 总被引:1,自引:0,他引:1
Kejie Lu Yi Qian Hsiao-Hwa Chen Shengli Fu 《IEEE network》2008,22(3):38-45
Recently, WiMAX has been proposed as an attractive wireless communication technology for providing broadband access for metropolitan areas. Despite its salient features from the technical perspective, the success of the WiMAX network depends on its capability of providing cost-effective solutions for a variety of existing and potential services. To address this issue, we advocate the design of a new network layer that can support multihop communications efficiently in WiMAX networks and that can fully exploit the features of the WiMAX standards. In particular, we first identify services that are important for broadband wireless network providers and investigate the requirements for different services. We then discuss now to design WiMAX networks by considering issues of efficiency, security, and reliability. The key observation is that WiMAX can be properly complemented by advanced connection management and network coding techniques. 相似文献
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Convergence of optical and wireless networks is a promising development for future access network architecture. A Radio over Fiber (ROF)-based network that converges Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX) technologies makes it possible to simultaneously transmit EPON baseband signals and WiMAX wireless Radio Frequency (RF) signals. This article elaborates on uplink and downlink transmission, redundancy protection, and roaming features of such a network. 相似文献
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A Survey on Mobile WiMAX [Wireless Broadband Access] 总被引:1,自引:0,他引:1
The IEEE 802.16 standard, commonly known as WiMAX, is the latest technology that has promised to offer broadband wireless access over long distance. Since 2001 WiMAX has evolved from 802.16 to 802.16d for fixed wireless access, and to the new IEEE 802.16e standard with mobility support. In this article we provide an overview of the state-of-the-art mobile WiMAX technology and its development. We focus our discussion on QoS provisioning and mobile WiMAX specification. 相似文献
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《Communications Magazine, IEEE》2001,39(9):115-121
It is an exciting time for broadband fixed wireless with key developments in frequency bands from 1 to 60 GHz and a range of new technologies being developed. While working on these new technologies, it is easy to forget that fixed wireless access will form part of an integrated communications environment of the future where users will have one communications device working in the home, at the office, and outdoors. This article predicts the communications environment of the next 20 years and looks at the role of fixed access within that environment. This involves assessing how fixed access systems will interface and integrate with in-home wireless networks, how their architecture will enable multiservice operators to utilize the same core network across a range of different access technologies, and how they will act as a channel to carry mobile traffic originating within the building. Based on the requirements this vision and architecture implies, this article critically assesses the different fixed wireless technologies available to date and compares their capabilities to provide future-proof broadband fixed wireless platforms 相似文献
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2007年之前,WiMAX仍然是宽带无线接入技术的主流,移动通信技术领域的配角.由于2007年ITU-R批准WiMAX成为IMT-2000标准,并且随着各国WiMAX频率许可证颁发,以及WiMAX论坛不断制定基于FDD工作方式的新标准,WiMAX正向主流移动通信技术的目标迈进. 相似文献
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目前,全球宽带通信市场发展迅速,无线化成为宽带接入的未来发展方向.提出在发展无线接入时需注意的若干问题.当前移动接入与固定接入的界限正逐渐变的得模糊,认为统一的标准有利于推动无线接入技术的发展,而且任何宽带无线接入技术必须支持话音业务.接下来剖析了WiMAX的发展情况,分析了WiMAX与3G的关系.最后提出应重视短距离低速率无线接入系统的发展. 相似文献
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WiMAX技术发展迅速,但是为了获得高效可靠的通信性能,并支持更高速率的移动环境,需要物理层关键技术进一步演进。为了支持移动性,IEEE802.16e标准(移动宽带无线接入)在IEEE802.16d标准(固定的宽带无线接入)的基础上进行了改进,在物理层引入了正交频分复用与多入多出相结合的技术,使传输速度成倍提高的同时能够支持一定的移动性。在未来的IEEE802.16m中还将会引入更加先进的空中接口技术。 相似文献
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Multimedia stream service provided by broadband wireless networks has emerged as an important technology and has attracted much attention. An all-IP network architecture with reliable high-throughput air interface makes orthogonal frequency division multiplexing access (OFDMA)-based mobile worldwide interoperability for microwave access (mobile WiMAX) a viable technology for wireless multimedia services, such as voice over IP (VoIP), mobile TV, and so on. One of the main features in a WiMAX MAC layer is that it can provide'differentiated services among different traffic categories with individual QoS requirements. In this article, we first give an overview of the key aspects of WiMAX and describe multimedia broadcast multicast service (MBMS) architecture of the 3GPP. Then, we propose a multicast and broadcast service (MBS) architecture for WiMAX that is based on MBMS. Moreover, we enhance the MBS architecture for mobile WiMAX to overcome the shortcoming of limited video broadcast performance over the baseline MBS model. We also give examples to demonstrate that the proposed architecture can support better mobility and offer higher power efficiency. 相似文献