Overview of mobile WiMAX technology and evolution

Mobile WiMAX is a fast growing broadband access technology that enables low-cost mobile Internet applications, and realizes the convergence of mobile and fixed broadband access in a single air interface and network architecture. Mobile WiMAX combines OFDMA and advanced MIMO schemes along with flexible bandwidth and fast link adaptation, creating a highly efficient air interface that exceeds the capacity of existing and evolving 3G radio access networks. WiMAX networks, built on all-IP network architecture for plug and play network deployments, can support a mix of different usage and service models. While some consider mobile WiMAX as a candidate for the fourth generation of mobile networks, others view it as the first generation of mobile Internet technologies emerging from a wider ecosystem targeting to extend the success of WiFi over wide area networks supporting mobility. This article provides a high-level overview of mobile WiMAX technology and its evolution roadmap from both radio and network perspectives.     

WiMAX物理层关键技术及其演进

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。     

基于IEEE802.16e移动宽带无线接入网的切换过程分析与实现

随着WiMAX组织的发展壮大加快了IEEE802.16标准的发展,移动WiMAX ——IEEE802.16e标准的提出更加引人注目.该标准对IEEE802.16标准进行了补充和拓展,定义了一个结合固定和移动宽带无线接入的系统,填补了高速无线局域网和高移动性蜂窝系统之间的空白.对IEEE802.16e标准中规定的移动宽带无线接入系统的切换过程进行了分析,并提出了该过程的软件实现方案.     

从WiMAX到LTE:不同宽带无线接入技术殊途同归

游牧和移动宽带无线接入将成为未来通信市场的重要需求.WiMAX正是针对这一需求而专门发展的,其性能强、效率高、成本低,具有灵活的体制,可通过配置满足各种应用场景的要求.同样,为了进入宽带无线接入市场,3GPP首先发展了被称为3.5G的HSDPA技术(可以大幅度提高分组数据的传输速率),2004年底又决定发展长期演进(LTE)计划,其指标和技术都与WiMAX相近,可以说是殊途同归.面对LTE的竞争,WiMAX要想在宽带无线接入市场中占有一席之地必须拥有好的频率,使用地面电视广播频率可提供大面积覆盖,降低成本.     

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.     

移动WiMAX技术分析和展望

移动WiMAX借助OFDMA等多项先进技术提供优质的移动宽带服务。它的设备制造、测试和认证发展迅速。移动WiMAX与3G技术互补,与E3G则呈现出竞争态势,但需求指标和核心技术的相似使其与后者的融合成为可能。     

移动WiMAX向主流技术进军

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.     

A Survey on Mobile WiMAX [Wireless Broadband Access]

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.     

An overview of next-generation mobile WiMAX technology - [WiMAX update]

The growing demand for mobile Internet and wireless multimedia applications has motivated the development of broadband wirelessaccess technologies in recent years. Mobile WiMAX has enabled convergence of mobile and fixed broadband networks through a common wide-area radio-access technology and flexible network architecture. Since January 2007, the IEEE 802.16 Working Group has been developing a new amendment of the IEEE 802.16 standard (i.e., IEEE 802.16m) as an advanced air interface to meet the requirements of ITU-R/IMT-advanced for 4G systems, as well as for the next-generation mobile network operators. Depending on the available bandwidth and multi-antenna mode, the next-generation mobile WiMAX will be capable of over-the-air datatransfer rates in excess of 1 Gb/s and of supporting a wide range of high-quality and high-capacity IP-based services and applications while maintaining full backward compatibility with the existing mobile WiMAX systems to preserve investments and continuing to support first-generation products. This tutorial describes the prominent technical features of IEEE 802.16m and the potential for successful deployment of the next generation of mobile WiMAX in 2011+.     

IEEE 802.16/WiMAX-based broadband wireless access and its application for telemedicine/e-health services

In this article we investigate the application of IEEE 802.16-based broadband wireless access (BWA) technology to telemedicine services and the related protocol engineering issues. An overview of the different evolutions of the IEEE 802.16 standard is presented and some open research issues are identified. A survey on radio resource management, traffic scheduling, and admission control mechanisms proposed for IEEE 802.16/WiMAX systems is also provided. A qualitative comparison between third-generation wireless systems and the IEEE 802.16/WiMAX technology is given. A survey on telemedicine services using traditional wireless systems is presented. The advantages of using IEEE 802.16/WiMAX technology over traditional wireless systems, as well as the related design issues and approaches are discussed. To this end, we present a bandwidth allocation and admission control algorithm for IEEE 802.16-based BWA designed specifically for wireless telemedicine/e-health services. This algorithm aims at maximizing the utilization of the radio resources while considering the quality of service requirements for telemedicine traffic. Some performance evaluation results for this scheme are obtained by simulations     

移动WiMAX的发展与应用

本文首先阐述移动WiMAX与其他宽带无线技术之间的关系,接着从标准进展、产业发展和运营状况等方面对移动WiMAX技术进行了深入的分析,然后针对WiMAX的应用方案给出了相关建议,最后对移动WiMAX发展中存在的问题进行了总结.     

A Versatile, Low Power, High Performance BiCMOS MIMO/Diversity Direct Conversion Transceiver IC for WiBro/WiMAX (802.16e)

This paper describes a dual signal path (MIMO) low power, high performance direct conversion WiBro/WiMAX 802.16e radio transceiver optimized for mobile applications and for coexistence with co-located Cellular and WLAN/Bluetooth systems.      

移动WiMAX系统的技术分析及对TD-SCDMA的发展启示

本文首先对移动WiMAX的主要技术进行分析,主要包括MIMO技术、OFDM／OFDMA技术及越区切换等,然后阐述了移动WiMAX目前的发展状况,就其对我NTD—SCDMA的发展提供的借鉴经验进行介绍。     

Seamless integration of mobile WiMAX in 3GPP networks

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.     

IEEE 802.16标准与WiMAX技术浅析

本文首先介绍了WiMAX的技术基础IEEE 802.16系列标准的制定及发展现状,并着重对该标准的媒体访问控制子层和物理层的技术特点进行了分析.文章将用于构建WLAN的IEEE 802.11系列标准与用于构建WMAN的IEEE 802.16系列标准进行了比较.在文章最后,作者描述了WiMAX技术的应用场景,尝试性提出了WiMAX的几点应用并对该项技术做了展望.     

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。     

毫米波视距MIMO安全通信技术研究

移动通信和信息社会的高速发展对宽带高速数据传输提出了较高的要求,而毫米波多输入多输出（multiple-input multiple-output,MIMO）技术成为实现高速安全数据传输的重要技术途径.考虑到一些特殊的需求和应用场景,比如对偏远地区的覆盖,构建应急通信系统,特别是军事宽带战术互联网,基于空中移动平台的毫米波MIMO技术成为当前研究的一个热点.本文充分调研国内外相关文献资料,阐述了毫米波视距（line-of-sight,LoS）MIMO信道建模、天线阵列优化、混合波束成形设计以及物理层安全等相关技术的当前进展、存在的挑战,并指出未来的研究方向,推动基于空中平台的毫米波MIMO系统的工程化应用.     

Multicast Broadcast Services Support in OFDMA-Based WiMAX Systems [Advances in Mobile Multimedia]

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.     

基于固网移动网融合(FMC)的宽带接入网系统

文章提出了3种WiMAX无线网络与EPON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.根据融合系统的具体架构,讨论了带宽分配,数据转发等系统控制和操作的优化处理.WiMAX与EPON的融合实现了固网移动网在接入网系统中的融合,为新一代宽带接入网技术提供了一个可行方案.     

Quality of service support in IEEE 802.16 networks

During the last few years, users ail over the world have become more and more accustomed to the availability of broadband access. This has boosted the use of a wide variety both of established and recent multimedia applications. However, there are cases where it is too expensive for network providers to serve a community of users. This is typically the case in rural and suburban areas, where there is slow deployment (or no deployment at all) of traditional wired technologies for broadband access (e.g., cable modems, xDSL). In those cases, the most promising opportunity rests with broadband wireless access technologies, such as the IEEE 802.16, also known as WiMAX. One of the features of the MAC layer of 802.16 is that it is designed to differentiate service among traffic categories with different multimedia requirements. This article focuses on mechanisms that are available in an 802.16 system to support quality of service (QoS) and whose effectiveness is evaluated through simulation.