IEEE论文：IEEE 802.16e Ⅲ型休眠模式 切换过程 休假排队 性能指标 成本函数

移动宽带无线接入技术IEEE 802.16e 综述- 2007-10-29 15:35:04 来源：解放军理工大学通信工程学院柯贤文张艳摘要：介绍了实现移动宽带无线接入的关键技术、IEEE 802.16e移动无线宽带接入标准及其物理层与MAC 层技术，并与IEEE 802.20移动无线宽带接入标准进行了简单比较。

关键词：移动无线宽带接入媒质接入控制层物理层1 移动宽带无线接入技术简介1.1 什么是宽带无线接入宽带无线接入是一种能够在无线空间环境中提供高速连接的技术，它使得用户终端通过无线的方式以与有线接入技术相近的数据传输速率和通信质量接入核心网络。

宽带无线接入是由基站和多用户终端组成的一种点到多点的通信网络，基站与各用户终端之间并不需要物理连线，而是通过户外天线与各用户终端进行高速的语音和数据通信。

现在发展的宽带无线接入技术可以支持的用户终端构成小规模的具有无中心、自组织、动态拓扑、多跳路由特性的Ad Hoc 网络，因此，宽带无线接入技术在高速Internet接入、信息家电联网、移动办公、军事、救灾、空间探险等领域具有非常广阔的应用空间。

1.2 移动宽带无线接入根据ITU-R 的M.1034-1 建议，无线接入可以分为：静止、步行、典型车速和高速车速四类，移动宽带无线接入(MBWA）就是能够为在典型车速和高速车速状态下提供无线宽带接入的系统，即上述分类中的后两类的系统。

与此相反，固定和游牧无线接入要求用户终端使用的时候保持静止，也称为便携性系统。

除了移动性分类的区别，移动无线和固定无线还有其他很多的区别，例如，使用的载波、技术支持、频谱分配、数据传输速率、应用业务、用户服务类别和设备等。

移动无线应用的典型频谱是为移动性分配的3.5GHz 以下专用许可频段，而固定无线系统典型应用的是非许可频段或分配给固定无线服务的许可频段。

1.3 移动无线宽带接入的关键技术空中接口部分需要解决的关键技术有：在高速数据传输方面主要有多天线、分集和波束成形技术、多用户检测和干扰抵消技术、自适应调制等；在高频传输的可靠性方面主要有纠错编码(Turbo 编码或LDPC 编码等)、自适应编码、重传机制；在非对称的多址接入和双工方面，由于其存在非对称性问题，可以考虑的双工方式主要有频分双工和时分双工两种模式；业务量和QoS 的MAC 层设计方面主要有业务量设计与QoS 保障的结合。

基于IEEE802.16e的QoS机制的研究及仿真【摘要】当今世界,科学技术日新月异的发展,尤其是通信技术的飞速发展,简单的语音和短信业务不能满足人们日常生活的要求。

IEEE 802.16e技术作为一种新兴的宽带无线接入技术,它为用户提供足够的带宽和高传输速率以及高频谱效率的多媒体业务,并用于解决“最后1km”的通信需求。

服务质量(QoS)是IEEE 802.16e系统的一个非常重要和具有挑战性的问题,虽然IEEE 802.16e的媒体接入(MAC)层具有QoS机制,但是并没有给出具体的实现方法,所以QoS机制成为非常热门的研究话题。

本文首先对IEEE 802.16产生的背景和发展现状进行了概括,然后分析IEEE 802.16e协议模型,主要研究MAC的公共部分子层的QoS机制,描述了有线调度算法和无线调度算法的原理和应用场景。

在前人提出的调度架构基础上,引入跨层设计的方案,得到一种跨层QoS调度架构,简单的介绍了调度架构中的各个组成模块。

最重要是将物理层技术和MAC层技术在跨层结构上充分融合,并且对接纳控制和上行带宽分配进行详细研究。

在此调度架构中采用的是简单的接纳控制技术,并且引入分级上行带宽分配方式。

前人对分级带宽分配进行了研究,但是在... 更多还原【Abstract】 Nowdays, with the development of science andtechnology, particularly the rapid development of communication technology, the simple voice and SMS services can not meet the needs of daily life. IEEE 802.16e is an emergingbroadband wireless access technology, which provides users with sufficient bandwidth, high transmission rate and multimedia services with high spectral efficiency, IEEE 802.16e solves"last a mile" communication needs. Quality of Service(QoS)requirements in IEEE 802.16e system is... 更多还原【关键词】IEEE802.16e；QoS；调度；跨层设计；【Key words】IEEE 802.16e；QoS；scheduling；cross-layer design；【索购硕士论文全文】Q联系Q：138113721 139938848 即付即发目录摘要3-4Abstract 4-5目录6-9第一章绪论9-171.1 背景和意义9-121.1.1 IEEE 802.16系列标准的发展10-111.1.2 IEEE 802.16系列标准的技术对比11-121.2 IEEE 802.16e的优缺点以及研究现状12-141.2.1 IEEE 802.16e的优点12-131.2.2 IEEE 802.16e的不足131.2.3 IEEE 802.16e的研究现状13-141.3 论文的主要贡献及其结构安排14-171.3.1 论文的主要贡献14-151.3.2 论文结构安排15-17第二章IEEE 802.16e MAC层结构分析17-312.1 IEEE 802.16e的网络拓扑结构17-192.2 MAC层的组成以及功能19-212.3 公共部分子层21-262.3.1 连接212.3.2 服务流21-232.3.3 网络接入与初始化23-252.3.4 调度的服务类型和QoS参数25-262.4 带宽请求和分配机制26-302.4.1 带宽请求(Requests) 272.4.2 轮询机制(Polling) 27-292.4.3 授权机制(Grants) 29-302.4.4 竞争带宽请求和解决的机制302.4.5 服务类型的带宽请求和授予机制302.5 本章小结30-31第三章IEEE 802.16e的QoS机制及调度算法的研究31-453.1 QoS的概念31-323.2 调度算法的研究32-393.2.1 有线网络中的调度算法32-353.2.2 无线网络中的调度算法35-393.3 QoS调度架构的研究39-413.4 上行带宽调度方法的研究41-433.5 本章小结43-45第四章一种改进的跨层QoS调度架构45-574.1 改进的QoS调度架构45-484.1.1 接纳控制模块464.1.2 跨层模块46-484.2 改进的上行带宽调度方法48-564.2.1 传统的DFPQ算法49-524.2.2 改进的DFPQ算法52-544.2.3 第二级调度54-564.3 本章小结56-57第五章系统的仿真平台实现57-675.1 OPNET14.5的介绍575.2 仿真模型的设计57-605.2.1 IEEE 802.16e系统的整体建模结构57-585.2.2 IEEE 802.16e MAC层节点建模58-605.3 仿真场景及参数的设定60-625.4 仿真结果与分析62-655.5 本章小结65-67总结与展望67-69 总结67展望67-69 参考文献。

IEEE 802.16e StandardWhat Will it Mean for Fixed Wireless Applications?NoticeThe information in this manual is subject to change without notice. All statements, information and recommendations in this manual are believed to be accurate, but are presented without warranty of any kind, expressed or implied. Users must take full responsibility for their use of any products.No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or by any information storage or retrieval system, without prior written consent from SR Telecom Inc.SR TELECOM, AIRSTAR, ANGEL, INSIGHT NMS, METROFLEX, METROPOL, SR500, SR500IP, SWING, WL500, and SYMMETRY are trademarks of SR Telecom Inc. All rights reserved 2004. All other trademarks are property of their owners. Information subject to change without notice.© 2005, SR Telecom Inc.All rights reserved. 1/1/05Printed in CanadaAbstractThe Institute of Electrical and Electronics Engineers (IEEE) 802.16-2004 standard, commonly referred to as 802.16d, was published in 2004. The 802.16e amendment to the standard is expected to be completed in the first half of 2005. Whereas the 802.16-2004 standard addresses fixed wireless applications only, the 802.16e standard can serve the needs of fixed, nomadic, and fully mobile networks.Although 802.16e is generally perceived as the mobile version of the standard, in reality it serves the dual purpose of adding extensions for mobility and including new enhancements to the Orthogonal Frequency Division Multiplexing Access (OFDMA) physical layer. This new enhanced 802.16e physical layer is now being referred to as Scalable OFDMA (SOFDMA) and includes a number of important features for fixed, nomadic, and mobile networks.Because of these advantages, most of the industry will build their 802.16e-based products using SOFDMA technology. However, the 802.16e standard is not just for mobility. There are also many compelling reasons for using SOFDMA in fixed broadband wireless access (BWA) networks. This paper focuses on the advantages that SOFDMA provides for fixed wireless applications.WiMAX Forum™ ComplianceThe 802.16-2004 standard, published in 2004, includes options for three different Physical (PHY) layers: single carrier, OFDM256, and OFDMA. The WiMAX Forum has thus far supported the OFDM256 physical layer within the802.16-2004 standard for first-generation WiMAX products.Since volume deployment of WiMAX-certified equipment is expected to be driven by nomadic and mobile applications, it is important to observe the direction of the 802.16e standard to understand the technology that will be used for thesemass-market deployments. Support within the IEEE for SOFDMA grew significantly throughout 2004, with many of the mobile vendors becoming more active. Momentum continues to build in 2005.In Korea, the Telecommunications Technology Association (TTA) has recently decided to align its wireless/broadband (WiBRO) high-speed Internet standard with SOFDMA as well. Intel has also announced at industry conferences that SOFDMA will be the PHY layer of choice for future fixed and portable WiMAX applications, such as indoor customer premise equipment (CPEs), notebooks, and Personal Digital Assistants (PDAs). This recent industry shift is important because SOFDMA is not backward compatible with OFDM256, which is the basis of most early "pre-WiMAX" equipment.The availability of WiMAX-certified products should help to significantly increase the overall competitiveness of fixed wireless equipment versus other technologies. Fixed BWA remains SR Telecom™'s primary focus; however, we also recognize that the volumes possible for fixed wireless access will never approach the same level as those expected for nomadic and mobile applications, such as notebooks and PDAs.History has shown that fixed wireless equipment that rides the cost curves of higher volume applications rapidly becomes more cost-effective than equipment built on technologies that are used exclusively for fixed wireless applications. Fixed BWA must leverage the investment for these higher-volume applications to reach the price points that are required to make BWA a resounding success. Economies of scale from nomadic and mobile networks, including notebooks and PDAs, will drive down the cost of all SOFDMA solutions.SR Telecom is a pioneer of OFDMA technology with our symmetry™ product line. We have the industry's only field-proven OFDMA technology and are convinced of the benefits that OFDMA brings to fixed wireless networks.SOFDMA BenefitsThe benefits of SOFDMA for fixed wireless applications, include the following:Lower Cost Driven by Volume Opportunity• Fixed wireless CPEs will be able to use the same modem chipset used in personal computers (PCs) and PDAs.• Base stations will be able to use the same chipsets being developed for low-cost WiMAX access points.• Increased volume will also justify the investment for higher-level integration of radio frequency (RF) chipsets, further driving down costs.• Peak-to-Average-Power-Reduction (PAPR) techniques incorporated within the standard will enable lower cost power amplifiers to be used for SOFDMAwithout compromising system gain.Non-Line-of-Sight (NLOS) Coverage• Basic capabilities of SOFDMA will offer similar coverage as OFDM256. Above these basic capabilities, there are several areas listed below where SOFDMA should outperform.• Important optional techniques for improving NLOS coverage, such as diversity, space-time coding, and Automatic Retransmission Request (ARQ), areincluded as a part of SOFDMA as they are for OFDM256. In some cases, the capabilities are further enhanced for SOFDMA; for example, hybrid-ARQ and additional diversity schemes.• Finer granularity of sub-channelization improves SOFDMA system gain to enable deeper indoor penetration.• Higher performance coding techniques; for example, Turbo Coding and Low-Density Parity Check (LDPC), are being implemented in first-generation SOFDMA chipsets, further improving system gain and NLOS coverage.(Optional higher-performance coding also exists with OFDM256, but is not implemented in most first-generation WiMAX chipsets.)• Downlink sub-channelization of SOFDMA enables additional flexibility for trading-off coverage versus capacity.• Volume opportunity for nomadic applications is encouraging lower-cost solutions (chipsets) to enable Adaptive Antenna Systems (AAS) andMultiple-Input-Multiple-Output (MIMO) for improved coverage.• SOFDMA sub-carrier spacing is independent of channel bandwidth. Scalability ensures that system performance is consistent across different RF channel sizes (1.25-14 MHz).• Larger Fast Fourier Transform (FFT) sizes of SOFDMA can cope with larger delay spreads making the technology more resistant to multipath fading that is characteristic of NLOS propagation, particularly with larger RF channels.Capacity• SOFDMA provides greater flexibility to trade-off data throughput with mobility.Fixed CPEs are still able to access the full bandwidth within any sector to get the same peak rates as with OFDM256.• Improvements in system gain enable the delivery of peak data rates to more subscribers within a cell, increasing the effective throughput of each basestation.Improved Frequency Reuse• By using Partially Used Sub-channeling (PUSC) mode on the downlink, SOFDMA can achieve better frequency reuse than what is possible withOFDM256; as a result, less spectrum will be required to deliver the sameoverall network capacity.Improved Security• 802.16e includes Advanced Encryption System (AES) functionality that service providers have been encouraging the WiMAX Forum to make mandatory for all WiMAX-certification.Option to Conveniently Upgrade Fixed Networks to Combined Fixed and Nomadic Networks in the Future• SOFDMA-based CPEs and base station sectors deployed initially in a fixed network will be compatible with the eventual deployment of nomadic-enabled networks.• Building fixed wireless networks using SOFDMA provides a future-proof solution for carriers considering evolution to nomadic or fully mobile WiMAX networks.ConclusionThe 802.16e standard is not just about mobility. A key part of the new amendment to the standard is the introduction of the SOFDMA technology that offers a number of technical advantages for fixed wireless applications, as well as a migration path to mobility.The 802.16e standard is about volume. By leveraging the same technology being integrated into notebooks and PDAs, networks based on SOFDMA will become the most cost-effective solution for carriers to also deploy for fixed wireless applications.Corporate Headquarters 8150 Trans-Canada Hwy.Montreal, QCH4S 1M5Canada info@。