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1.
Recent mobile devices are integrated with multiple network interfaces. Users want their devices connected to the network anytime anywhere. It is highly feasible for a user to change connection to another network for users that leave the service area of its current serving network, where handover needs to be executed seamlessly such that ongoing service sessions are not interrupted. The handover operation not only requires switching the interfaces within a device but also involves seamless reconfiguration of the supporting networks. In this article, an improved IP-based vertical handover technology for mobile WiMAX [1, 2], 3GPP legacy systems (i.e., Global System for Mobile communications and Universal Mobile Telecommunications System) [3, 4], and 3G Long Term Evolution [5, 6] is presented, which is based on existing optimized handover techniques between mobile WiMAX and 3GPP accesses [7?9]. Formerly proposed 3GPP WiMAX optimized VHO solutions introduced new elements, such as the forward attachment function and access network discovery and selection function. The ANDSF supports the discovery of target access, and the FAF provides the functionality that authenticates the UE before the execution of VHO. However, the previous technique has limitations that result in data loss and abnormal disconnection to the source access [7?9]. This article provides a solution by introducing an additional network element called the data forwarding function (DFF) that eliminates the data loss during VHO execution. In addition, the DFF resolves the problem of abrupt disconnection to the source network. The simulation results show that the proposed VHO technique is effective in minimizing data loss during VHO execution between mobile WiMAX and 3GPP networks. As the proposed solution of this article is an IP based handover solution, it can be similarly applied to other communication networks.  相似文献   

2.
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   

3.
Overview of mobile WiMAX technology and evolution   总被引:1,自引:0,他引:1  
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.  相似文献   

4.
Phases I and II of the WINNER project contributed to the development, integration, and assessment of new mobile network techniques from 2004 to 2007. Some of these techniques are now in the 3GPP LTE and IEEE 802.16 (WiMAX) standards, while others are under consideration for LTE-Advanced and 802.16m. The WINNER+ project continues this forwardlooking work for IMT-advanced technologies and their evolution, with a particular focus on 3GPP LTE-Advanced. This article provides an overview of the WINNER system concept and several of its key innovative components.  相似文献   

5.
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   

6.
The growing demand for wireless Internet services is accelerating the evolution of wireless networks toward all-IP architecture, and the mobile WiMAX network is a prominent example. Although currently deployed mobile WiMAX networks use hierarchical architecture, flat architecture is feasible and specified as a design alternative in the mobile WiMAX standard. In flat architecture the functionalities of the ASN-GW and BS are consolidated into a single element. In this article we first discuss the benefits and challenges of flat architecture mobile WiMAX networks. We then present a scheme to deal with the seamless mobility issue, which is one of the key challenges of the flat architecture. The proposed scheme combines two standard IP-mobility protocols, Proxy Mobile IP and Fast Mobile IP, and customizes them for IEEE 802.16e-based mobile WiMAX networks. This provides interoperability with existing mobile WiMAX networks. We demonstrate the viability of the proposed scheme through simulations using NS-2.  相似文献   

7.
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   

8.
The Internet has experienced tremendous expansion in the past several years. Demands for IP multimedia services are emerging. The third-generation (3G) wireless networks aim to support mobile users with numerous Internet services. 3G standards organizations are developing IP multimedia subsystems (IMS) to achieve seamless integration between Internet and 3G networks. Moreover, the collaboration between IETF, 3GPP, and 3GPP2 is essential to the development of IMS for next-generation networks. This article first provides an overview of 3GPP and 3GPP2 IMS and illustrates the IMS requirements, architectures, and functional models. We then discuss potential scalability issues in IMS. This article provides guidance for constructing a robust and scalable IMS.  相似文献   

9.
Towards satisfying the requirements of International Mobile Telecommunications–Advanced, both the Institute of Electrical and Electronics Engineers (IEEE) and Third Generation Partnership Project (3GPP) introduced revolutionary wireless technologies, exploiting advanced technologies and architectures. Both IEEE's 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)) and 3GPP's Long Term Evolution have been introduced to accommodate the increasing demand for mobile services and applications. To realize the true potential of these technologies, however, opportunistic frameworks for radio resource management must be designed to exploit the adaptive nature of mobile traffic. The utility optimized quality‐of‐service (QoS) framework proposed in this paper for the mobile WiMAX networks achieves this objective. To maintain support for QoS guarantees, the framework capitalizes on the adaptive nature of WiMAX traffic by individually linking connections with a utility function designed to both uphold the end users’ perceived performance and determine bandwidth allocations by a search tree maximization algorithm. In doing so, bandwidth utilization is maximized for all active connections, and blocking and dropping probabilities for new and handover calls, respectively, are minimized. The framework is evaluated through an extensive simulation model and is shown to outperform state‐of‐the‐art solutions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

10.
随着WiMAX技术和产业链的成熟,WiMAX仍然没有寻找到一个全球统一的可用频段,这使得WiMAX很难在全球市场获得突破,更加难以形成规模效应。在这种情况下,WiMAX阵营决定加入ITU-R的3G及4G标准,无疑使WiMAX与现有各个3G技术将展开全面的竞争。目前,移动WiMAX产业仍然不算成熟,但商用进程却在逐步加快。最值得关注的仍然是移动WiMAX今后在移动通信技术领域中的地位。移动WiMAX已经不满足定位于3G的补充技术,而是直接与其进行正面交锋,这给今后的移动通信市场格局增加了很多变数,尤其是很多设备厂商在发展3G的同时也涉足于WiMAX产业,而运营商也将在众多移动通信技术中进行选择。  相似文献   

11.
Network-based mobility management in the evolved 3GPP core network   总被引:1,自引:0,他引:1  
A key aspect of the 3GPP system architecture evolution is the specification of an evolved packet core that supports multiple access networks. The EPC enables operators to deploy and operate one common packet core network for 3GPP radio accesses (E-UTRAN, UTRAN, and GERAN), as well as other wireless and wireline access networks (e.g., eHRPD, WLAN, WIMAX, and DSL/Cable), providing the operator with a common set of services and capabilities across the networks. A key requirement of the EPC is to provide seamless mobility at the IP layer as the user moves within and between accesses. This article provides an overview of the EPC specifications that use a network-based mobility mechanism based on Proxy Mobile IPv6 to enable mobility between access networks. An important facet of providing seamless mobility for a user?s sessions across technologies is to ensure that quality of service is maintained as the user moves between accesses. An overview of the ?off-path? QoS model to supplement PMIPv6 is also provided.  相似文献   

12.
侯自强 《电信科学》2005,21(10):18-21
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.  相似文献   

13.
Efficient support of voice traffic has always been one of the key metrics for evaluating and selecting radio access technologies. Even for next-generation broadband wireless technologies primarily focused on the mobile Internet, special handling of VoIP traffic in the physical and MAC layers is required to maximize voice capacity. While Mobile WiMAX Release 1.0 and 802.16e have all the key features necessary to support mobile VoIP traffic, special attention is given in Mobile WiMAX Release 1.5 and 802.16REV2 to further optimizing VoIP capacity through reduction in the MAC layer overhead associated with signaling messages. This article focuses on features and solutions used in Mobile WiMAX and the 802.16 standard to support voice traffic and the expected performance in Release 1.0/802.16e-2005, as well as gains from optimization concepts such as persistent allocation added in Release 1.5/802.16REV2. In each case, MAP overhead reduction and the projected improvements in VoIP capacity are presented using typical industry accepted models and assumptions. The results show about 15 percent increase in bidirectional VoIP capacity.  相似文献   

14.
基于IEEE802.16e移动宽带无线接入网的切换过程分析与实现   总被引:3,自引:0,他引:3  
窦赫蕾  马楠  王莹  田辉  张平 《世界电信》2006,19(5):44-47
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.  相似文献   

15.
沈嘉 《电信科学》2006,22(6):24-28
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   

16.
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   

17.
UMTS overview     
The Universal Mobile Telecommunications System (UMTS) as specified by the Third Generation Partnership Project (3GPP) was formally adopted by the ITU as a member of its family of IMT-2000 Third Generation Mobile Communication standards in November 1999. This paper provides some background to the UMTS standard and an overview of the system architecture. Some information about the current status of technology trials is provided as well as predictions for the services that future UMTS networks are likely to deliver to the end user  相似文献   

18.
王一凡  蔡杰  张勇 《现代电信科技》2007,37(4):15-18,32
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。  相似文献   

19.
This article highlights WiMAX network requirements and functionality for integration with 3GPP Rel 7 IMS/PCC architectures.  相似文献   

20.
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。  相似文献   

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