基于WiMAX技术的大客户宽带无线接入方案

WiMAX是一项新兴的远距离宽带无线接入技术,基于IEEE802.16标准,是为无线城域网WiMAN量身打造,解决用户"最后一公里"问题的宽带无线接入技术.WiMAX提供固定、便携、移动形式的无线宽带连接,并最终能够在不需要直接视距基站的情况下提供移动无线宽带连接.     

WiMAX点对点宽带无线接入容量分析

随着通信技术的迅猛发展,移动宽带化和宽带移动化是通信网发展的必然趋势。WiMAX城域网无线宽带接入技术,可提供大范围及高速率无线接入,同时支持视距传输和非视距传输,能提供面向互联网的高速无线连接。WiMAX可作为线缆和用户数字线的无线扩展技术,实现无线宽带接入。首先简要介绍WiMAX的应用模式,然后重点分析其点对点应用中上行链路和下行链路的通信容量,提供相关工程技术人员进行方案设计的参考。     

从WiMAX到LTE：不同宽带无线接入技术殊途同归

1．前言 随着PDA和笔记本电脑的发展普及，用户希望能够随时随地上网，一个新的市场——“宽带无线游牧／移动接入”正在兴起。宽带无线接人技术面向一个固定和移动通信融合的新市场，它可提供与宽带有线固定接人并行的宽带无线接入业务，支持游牧和移动应用。     

WiMAX前景展望

随着移动通信和宽带业务的发展，一个新兴的宽带无线接人市场正在兴起。2．5G／3G手机移动数据业务和宽带无线接入是两个不同的市场。宽带无线接入是一个面向固定和移动通信融合的新市场，提供与宽带有线固定接入并行的宽带无线接入，支持游牧和移动应用。它与宽带固定接入使用共同的互联网核心网，应用业务支持AAA系统。它使得用户能够在任意时间和地点接入互联网，充分发挥互联网无所不在的特性。     

发展无线接入需注意的若干问题

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.     

WiMAX——超级连接世界的真正无线宽带

近年来，WiMAX技术一直得到国内外通信界的关注。WiMAX技术定位于城域级无线宽带接入，以其覆盖范围广、传输距离远、传输速率快等特点得到国内外众多厂商和专家学者的青睐。起初，WiMAX仅定位于固定的宽带无线接入，作为xDSL、Cable等有线接入的补充，提供对互联网的高速连接。而后，WiMAX将目光投向了更广阔的移动业务市场。2005年12月，WiMAX移动版本的标准IEEE802．16e得到批准，2006年2月正式发布，这无疑又推动了WiMAX商用化的进程。可以预见，WiMAX在未来的无线宽带移动通信领域将占据相当重要的主导地位。[第一段]     

浅析WiMAX技术及其测试

当前,宽带无线接入系统的发展已经成为电信业普遍关注的话题,各种技术标准及应用层出不穷.本文主要介绍WiMAX的相关技术及其测试,并针对WiMAX等宽带无线接入系统在应用中的测试问题展开讨论.     

WiMAX技术研究及发展现状

WiMAX是以IEEE802.16系列协议为基础的宽带无线接入技术,可替代现有的xDSL和有线连接方式,提供面向互连网的固定和移动形式的高速连接,符合未来通信发展趋势。文章从技术角度分析WiMAX技术,介绍WiMAX标准的进展,将其与其他主流无线接入技术进行比较,探讨WiMAX在中国的发展及部署状况,并对其前景进行展望。     

WiMAX系统及其设备研发

文章根据WiMAX系统的市场定位及设备需求,较详细地探讨了WiMAX系统及设备研发需要考虑的主要方面,包括需求和产品定义、技术整合、产品架构,以及目前产业链发展现状及技术走向,并从中得出了一些有价值的结论.文章认为WiMAX产品研发需要在借鉴WiFi模式的同时更多地完成技术整合,WiMAX必须继续坚持其开放性、低成本及新技术的发展方向,致力于宽带无线接入(BWA)及移动宽带无线接入(MB-WA)相互兼容、相互补充的发展之路.     

WiMAX标准及产业发展

一、WiMAX标准的进展 1.IEEE802.16标准化现状 WiMAX技术是目前国际上影响力最大的宽带无线接入技术,该技术基于IEEE 802.16空中接口,而WiMAX是IEEE 802.16技术在市场推广中采用的名称.IEEE802.16标准的空中接口包括IEEE 802.16d(802.16-2004)和IEEE 802.16e(802.16-2005)两个空中接口规范,前者是固定宽带无线接入系统空中接口规范(频段:10GHz～66GHz和＜11GHz),于2004年通过,不支持移动环境;后者是固定和移动宽带无线接入系统空中接口规范(频段＜6GHz,于2005年通过),支持便携和移动环境,最终支持的移动速度可以达到120km/h.     

Fixed Mobile Convergence Architectures for Broadband Access: Integration of EPON and WiMAX [Topics in Optical Communications]

EPON and WiMAX are two promising broadband access technologies for new-generation wired and wireless access. Their complementary features motivate interest in using EPON as a backhaul to connect multiple dispersed WiMAX base stations. In this article we propose four broadband access architectures to integrate EPON and WiMAX technologies. The integrated architectures can take advantage of the bandwidth benefit of fiber communications, and the mobile and non-line-of-sight features of wireless communications. Based on these integrated architectures, we elaborate on related control and operation issues to address the benefits gained by this integration. Integration of EPON and WiMAX enables fixed mobile convergence, and is expected to significantly reduce overall design and operational costs for new-generation broadband access networks.     

WiMAX关键技术及网络结构探讨

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。     

移动WiMAX无线技术研究

移动WiMAX作为移动和固定宽带网络融合的宽带无线解决方案,具有宽频无线接入技术和灵活的网络结构,在宽带移动网络的演进过程中必将发挥重要的作用。研究了移动WiMAX采用的无线技术,介绍了波束形成、空时编码和空间复用技术,分析了具有自适应MIMO转换技术的自适应智能天线系统,为了保证边缘用户的连接质量,引入了有别于传统频率复用技术的部分频率复用技术,最后简单介绍了移动WiMAX支持的多播和广播业务。     

WiMAX技术应用及其发展前景

WiMAX被定义为无线城域网解决方案。它的技术应用十分广泛。大致可以分为固定接入应用、游离式接入应用、全移动接入应用、便携式接入应用几方面。可以为不同的用户提供不同的应用领域。特别是在政府公共事业中的应用非常突出，并且将成为IPTV无线到户的另一种选择。此外，预测了WiMAX的发展前景。     

The Mobile Broadband WiMAX Standard [Standards in a Nutshell]

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.     

Compact multidimensional broadband wireless: the convergence of wireless mobile and access

Broadband wireless communications have gained increased interest during the last few years. This has been fuelled by a large demand on high-frequency utilization as well as a large number of users requiring simultaneous high-data-rate access for the applications of wireless mobile Internet and e-commerce. The convergence of wireless mobile and access will be the next storm in wireless communications, which will use a new network architecture to deliver broadband services in a more generic configuration to wireless customers, and support value-added services and emerging interactive multimedia communications. Large bandwidth, guaranteed quality of service, and ease of deployment coupled with the great advancements in semiconductor technologies make this converged wireless system a very attractive solution for broadband service delivery.     

WiMAX networks: from access to service platform

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.     

Broadband fixed wireless access as a key component of the futureintegrated communications environment

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     

The future generations of mobile communications based on broadband access technologies

The forthcoming mobile communication systems are expected to provide a wide variety of services, from high-quality voice to high-definition videos, through high data rate wireless channels anywhere in the world. The high data rate requires broad frequency bands, and sufficient broadband can be achieved in higher frequency bands such as microwave, Ka-band, and millimeter-wave. Broadband wireless channels have to be connected to broadband fixed networks such as the Internet and local area networks. The future-generation systems will include not only cellular phones, but also many new types of communication systems such as broadband wireless access systems, millimeter-wave LANs, intelligent transport systems, and high altitude stratospheric platform station systems. Key to the future generations of mobile communications are multimedia communications, wireless access to broadband fixed networks, and seamless roaming among different systems. This article discusses future-generation mobile communication systems.