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1.
IEEE 802.16/WiMAX-based broadband wireless access and its application for telemedicine/e-health services 总被引:2,自引:0,他引:2
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 相似文献
2.
A Cross-Layering Design for IPv6 Fast Handover Support in an IEEE 802.16e Wireless MAN 总被引:1,自引:0,他引:1
Broadband wireless access networks, such as the IEEE 802.16 standard for wireless metropolitan area networks (WMANs), aim to provide high bandwidth, low-cost, scalable solutions that extend multimedia services from backbone networks to wireless users. Because of a larger coverage area, portability and mobility have become significant issues for providing high quality mobile services, as it is crucial to minimize handover latency and maintain IP session continuity. As a result, such issues were addressed by the IEEE 802.16e task group on the mobile WMAN. However, the scope of the IEEE 802.16e standard did not include cross-layering approaches for the enhancement of upper layer handover performance. This article proposes a new cross-layering design for fast IPv6 handover support over IEEE 802.16e. First, we describe the IEEE 802.16 deployment architectures, as well as the link layer, handover procedures in IEEE 802.16e. Next, we describe the operation of fast IPv6 handover and point out the need for interaction between the network layer and the link layer for proper performance. Then, we propose a new cross-layering design to achieve a proper behavior of the fast IPv6 handover over IEEE 802.16e. Finally, we present handover scenarios for the proposed techniques and discuss the major factors that contribute to the handover latency. 相似文献
3.
Der‐Jiunn Deng Li‐Wei Chang Chih‐Heng Ke Yueh‐Min Huang J. Morris Chang 《International Journal of Communication Systems》2009,22(2):119-133
WiMAX is a promising broadband wireless networking technology and is expected to take the place of broadband access solutions such as DSL and cable. Owing to its superior support in mobility, it is expected to provide integrated voice and data service to realize broadband mobile computing. In order to reach better quality‐of‐service (QoS) requirements for real‐time applications, the IEEE 802.16e standard defines five different services among traffic categories with different multimedia requirements. However, the problem of choosing the right set of medium access control parameters and packet scheduling policy to provide strict QoS guaranteed in IEEE 802.16e Broadband Wireless Access (BWA) systems remains unsolved and left as an open issue. In this paper, we propose a novel polling‐based uplink packet scheduling policy for real‐time Polling Service and extended real‐time Polling Service (rtPS/ertPS) traffic to support real‐time applications, with strict delay requirements, such as variable bit rate (VBR) traffic in IEEE 802.16e BWA systems. The proposed transmit‐permission policy can derive sufficient conditions such that all the rtPS/ertPS sources satisfy their time constraints to provide deterministic QoS guarantees. In addition to theoretical analysis, simulations are conducted to evaluate the performance of the proposed scheme. As it turns out, our design provides a good quality performance in the IEEE 802.16e BWA systems. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
4.
Pontes A.B. dos Passos Silva D. Jailton J. Rodrigues O. Lopes Dias K. 《Wireless Communications, IEEE》2008,15(5):86-95
Recently there has been much effort, in both academia and industry, to integrate a plethora of wireless technologies in order to provide ubiquitous broadband access to mobile users. Handover management is still one of the most challenging issues to be solved for seamless integration of wireless networks. This article addresses the integration of IEEE 802.11 WLANs and IEEE 802.16 WMANs, focusing mainly on the handover management aspects. First, we describe architectures, futuristic application scenarios such as the envisioned heterogeneous multihop wireless networks (HMWNs) and moving networks, as well as the related research issues. Second, we present IEEE 802.21, a new emerging standard aimed at providing a framework for media-independent handover (MIH) among heterogeneous networks. Finally, we discuss how the MIH framework can help handover management for the integrated network. 相似文献
5.
移动宽带无线城域网关键技术及其展望 总被引:4,自引:0,他引:4
对新一代宽带无线接入技术IEEE802.16e中的关键技术及其标准化最新进展进行了讨论,针对IEEE802.16e在网络规划和性能提升方面还存在的问题以及今后宽带无线接入技术领域的发展进行了分析和探讨。 相似文献
6.
One of the promising applications of IEEE 802.16 (WiMAX)-based wireless mesh/relay networks is to provide infrastructure/backhaul support for IEEE 802.11-based mobile hotspots. In this article we present an architecture for integrating IEEE 802.11 WLANs with IEEE 802.16-based multihop wireless mesh infrastructure to relay WLAN traffic to the Internet. The major research issues in this integrated architecture are outlined and related work is reviewed. A game-theoretic model is developed for radio resource management in this integrated network architecture. In particular, a multiplayer bargaining game formulation is used for fair bandwidth allocation and optimal admission control of different types of connections (e.g., WLAN connections, relay connections, and connections from standalone subscriber stations) in an IEEE 802.16 base station/mesh router. Both connection-level and inconnection-level performances for this bandwidth management and admission control framework are presented 相似文献
7.
IEEE 802.16和WiMax的组网技术 总被引:3,自引:0,他引:3
如何提高网络资源利用率和网络传输效率是无线通信领域面临的难题。作为宽带无线接入系统的标准,IEEE802,16在物理层采用正交频分复用技术和灵活的编码调制方式采提高传输速度和性能;在MAC层采用预约与竞争相结合的调度机制,以连接、服务流等与服务质量(QoS)相关的概念为基础。在入网与初始化、帧结构设计上优化设计,提高网络吞吐量,降低网络时延,使网络配置更加灵活。WiMAX基于IEEE802.16技术标准。采用点对多点(PMP)方式实现灵活组网,是宽带无线接入系统的典型血用技术。 相似文献
8.
《Wireless Communications, IEEE》2007,14(1):4-5
The special section features six articles that focus on radio resource management issues in IEEE 802.16/WiMAX-based broadband wireless systems. This guest editorial discusses the major issues pertaining to the topic and summarizes the articles included in this section. 相似文献
9.
Wireless communications play an important role in improving transportation environment safety and providing Internet access
for vehicles. This paper proposes a QoS-aware two-level uplink dynamic bandwidth allocation (DBA) algorithm for IEEE 802.16j-based
vehicular networks. IEEE 802.16j is an extension of standard IEEE 802.16 to support relay mode operation where traffics from/to
subscriber stations (SS) are relayed to/from a base station (BS) via a relay station (RS). In such a vehicular network, the
IEEE 802.16j BSs are installed along a highway, RSs are installed in large vehicles such as coaches, and the 802.16j interface
is equipped on SSs such as individual passengers’ mobile devices within a moving coach. In the proposed DBA algorithm, a utility
function, which considers characteristics of different types of services, is designed. The objective of the proposed two-level
DBA algorithm is to allocate bandwidth to different types of services from BS to RSs and then from a RS to SSs with given
quality of service (QoS) requirements. It aims at maximizing the utility of the overall network and minimizing the average
queuing delay of the overall network. The simulation results show the effectiveness and efficiency of the proposed DBA algorithm. 相似文献
10.
Hala B. Nafea Mustafa M. Sallam Fayez Wanis Zaki 《Wireless Personal Communications》2018,102(1):183-200
Power saving represents a vital role in mobile communications networks such as IEEE 802.16m and LTE. Modern user equipment (UEs) require high data rates and low power consumption. It is found that arranging sleep mode mechanisms ensures UE battery longer lifetime. In this paper, different sleep mode mechanisms are investigated for both IEEE 802.16m and LTE networks. The analyses are based on Markov and Semi-Markov chains. It is focused on the determination of UE transition state. Web traffic model parameters were considered in MATLAB simulation and a comparison assessment was conducted between WiMAX IEEE 802.16m and LTE DRX. It was found that LTE DRX sleep mode provides more power saving than WiMAX IEEE 802.16m sleep mode. The study is now implemented for 5G networks with encouraging results. 相似文献
11.
Relay Technologies for WiMAX and LTE-Advanced Mobile Systems 总被引:4,自引:0,他引:4
Yang Yang Honglin Hu Jing Xu Guoqiang Mao 《Communications Magazine, IEEE》2009,47(10):100-105
Relay technologies have been actively studied and considered in the standardization process of next-generation mobile broadband communication systems such as 3GPP LTE-Advanced, IEEE 802.16j, and IEEE 802.16m. This article first introduces and compares different relay types in LTE-Advanced and WiMAX standards. Simulation results show that relay technologies can effectively improve service coverage and system throughput. Three relay transmission schemes are then summarized and evaluated in terms of transmission efficiency under different radio channel conditions. Finally, a centralized pairing scheme and a distributed pairing scheme are developed for effective relay selection. Simulation results show that the proposed schemes can maximize the number of served UE units and the overall throughput of a cell in a realistic multiple-RS-multiple-UE scenario. 相似文献
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13.
Christian Hoymann 《Wireless Personal Communications》2006,36(4):363-385
Advanced antenna technologies and algorithms have been developed during the last years. But until today, advanced antenna algorithms in the physical layer and the modes of operation in medium access layers have not been integrated in modern wireless systems. As one of the first standards the metropolitan area network IEEE 802.16 provides means to support smart antenna techniques.After a detailed introduction of the medium access control layer this article outlines the support of space division multiple access (SDMA) techniques by the wireless metropolitan area network IEEE 802.16. New concepts are introduced that allow and further optimize the use of SDMA techniques brought by intelligent antennas. First, the possibility to enable SDMA in the IEEE 802.16a-2003 protocol is investigated, and second the support of SDMA in the revised 802.16-2004 standard is elaborated in detail. To overcome current limitations of 802.16a-2003, an enhanced control structure is introduced in 802.16-2004 that masters a concurrent transmission and reception of data to/from several different subscriber stations. The approach facilitates a fully flexible structure which significantly improves system capacity.
Christian P. Hoymann received his Diploma degree in electrical engineering from RWTH Aachen University in 2002. Before he served a student internship at SIEMENS Corporate Research, Princeton, USA. Since 2002 he is employed as a Research Assistant at the Chair of Communication Networks (ComNets) of RWTH Aachen University where he is working towards his Ph.D. degree.He worked in the fields of traffic engineering and dimensioning of GSM/GPRS networks together with his project partners at D2 Vodafone. He was actively involved in the IST-STRIKE project where smart antenna systems had been integrated in Metropolitan Area Networks. His current research interests include the optimization of MANs especially in consideration of smart antenna technologies such as SDMA and relaying technologies such as Mesh.Mr. Hoymann has published several conference and journal papers and was actively involved in the standardization of SDMA technologies for IEEE 802.16. 相似文献
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15.
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+. 相似文献
16.
小区搜索是IEEE 802.16e系统的关键技术之一.由此提出了一种低复杂度的快速联合小区搜索和整数倍频偏估计算法的VLSI结构.该结构采用差分估计方法,有效地解决了频率选择性衰落信道对检测性能的影响.详细描述了该结构的各组成单元和设计方法,并在Altera公司的EP2S130器件上进行了仿真综合验证.验证结果表明,该模块最高工作频率为103.7MHz,能够正常应用于IEEE 802.16e接收机或其他类似通信系统. 相似文献
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18.
Bong-Ho Kim Jungnam Yun Yerang Hur Chakchai So-In Raj Jain Abdel-Karim Al Tamimi 《Communications Magazine, IEEE》2009,47(6):132-141
The mobile WiMAX system is based on IEEE 802.16e, which defines radio interface supporting several classes of Internet Protocol applications and services. While the mobile WiMAX system is being deployed, IEEE 802.16m TG is developing an amendment to the IEEE 802.16e to greatly improve the system performance, and it is focusing not only on the PHY and MAC performance but also on a level of end-to-end performance improvement that includes the scope of the network and application to embrace the strong market request and interest. To evaluate the mobile WiMAX system capacity and performance, all the aspects of performance evaluation ? from air link to application ? are required. For the network and application-level capacity and performance analysis, we first provide an overview of mobile WiMAX systems, especially of the OFDMA/TDD systems of IEEE 802.16e and then describe subscriber and application profiles that include traffic-mix ratio, data-session attempts for applications, diurnal-application traffic distribution, and the application-traffic model. Afterward, the simulation results of network- traffic characteristics and demand estimation are provided. Finally, in the last section, we provide simulation results of end-to-end application performance evaluation using the examples of VoIP and a TCP/IP performance-enhancement method that can be implemented in the mobile WiMAX MAC or MAC/IP cross layer. 相似文献
19.
IEEE 802.16 Mesh Schedulers: Issues and Design Challenges 总被引:1,自引:0,他引:1
IEEE 802.16 mesh mode defines three types of resource scheduling: coordinated centralized, coordinated distributed, and uncoordinated distributed. While the standard defines the required procedures and messages for each scheduler, it does not offer encouraging means to provide performance, reliability, or QoS. In this article we outline the issues of IEEE 802.16 mesh schedulers. We also survey representative proposals and qualitatively evaluate them against these issues. More critically, we identify key challenges that have not been addressed so far in the literature to motivate work in this area of research. 相似文献
20.
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