无线宽带网络及其演进策略

首先回顾了无线宽带网络的发展状况,因特网和移动通信都以极高的速度普及和增长,并为构建未来的无线宽带网络奠定了基础。介绍了当前的研究热点,包括WLAN、3G、4G、AdHoc等,对它们的特点进行了比较,分析了各自在未来网络融合中所起的作用。指出了无线宽带网络发展是一个循序渐进的过程,介绍了通过网络融合逐步过渡到无线宽带网络的策略,重点对多跳网络的可融合性进行了分析。最后指出无线宽带网络所面临的挑战,并预测了未来无线宽带网络的发展趋势。     

Hop-by-hop toward future mobile broadband IP

We try to give some perspectives on likely trends in future wireless broadband networking. The treatment is an exploration of some technologies; due to the requirement to cover the topic from a broad perspective, it is not possible to go into technical details. We review current developments toward future mobile broadband networks, and then present the 4G paradigm of trying to combine heterogeneous networks, both cellular wireless hotspots and sensor networks, together with Internet protocols. We show how different networks play their own roles in the emerging infrastructure so that we can hop by hop wave the broadband network from mobile devices toward the fiber optic core network.     

Network Architectures for 4G: Cost Considerations [Wireless Broadband Access]

As 3G wireless networks evolve toward 4G, various wireless network technology organizations are considering a major redesign of the network architecture. We present a perspective on such a redesign motivated primarily by cost considerations. We examine some tenets for the design of 4G wireless network architectures that are aimed at improving costs in various aspects of the network. One tenet is the maximization of economies of scale by partitioning the functionality among network elements in a way that maximizes the potential domain of applicability of the network elements. Another is reduction of the number of distinct types of network elements needed by flattening the levels of hierarchy in the execution of various functions. We explain our reasoning by illustrating a way of redesigning the current 3GPP network architecture based on these tenets.     

Services in interworking 3G and WLAN environments

Interworking WLANs and 3G mobile networks are expected to provide ubiquitous wireless communications at high data rates and a large variety of services with variable bandwidth and QoS requirements, across a wide range of propagation environments and mobility conditions, using dual mode terminals. The interworking of the two networks is a major step toward a new generation of wireless networks in which other radio technologies are also be integrated. In this article we present possible architectures that enable the interworking of 3G and WLAN networks. We then address the capabilities of various terminal types and describe future services in the interworking environment. Finally, we present market forecasts on terminal and service demand growth.     

Mobility support across hybrid IP-based wireless environment: review of concepts, solutions, and related issues

The 4G or Beyond 3G wireless networks is consist of IP-based heterogeneous access networks from 3G cellular, WiFi, WiMAX to other emerging access technologies such as mesh networks. The key objective of designing the next generation wireless networks is to support of mobile subscribers. To support the mobile host in the hybrid wireless access technologies, many solutions based on network protocol stack have been proposed in the literature. In this article, after review of mobility concepts, a special attention is given to some of the mobility management methods as well as handover techniques across various wireless access networks. We have also compared the major mobility protocols in each layer for their features. Finally, some of the open issues that needed to be addressed in mobility management protocol in the next generation wireless networks are outlined.     

Software testing for wireless mobile computing

4G wireless networks make it increasingly difficult to develop and test application software for mobile terminals in comparison with 3G or earlier generations. These 4G networks incorporate wireless LAN technologies, and mobile terminals can access the services provided by LANs as well as global network services. Therefore, software running on mobile terminals may depend on not only its application logic but also on services within the LANs to which the terminals are connected. To construct correct software to run in mobile terminals for 4G wireless networks and wireless LANs, it must be tested in all the networks to which the terminal could be moved and be connected. This article presents a new approach, called flying emulator, to testing software designed to run on mobile terminals. Like existing approaches, the approach provides software-based emulators of its mobile terminals for software designed to run the terminals. It is unique because it constructs emulators as mobile agents that can travel between computers. These emulators can carry the target software to the networks to which the terminals are connected and allow it to access services provided by the networks in the same way as if it was moved with and executed on the terminals connected to the networks. This article describes the idea of the approach, its implementation, and our experience with a typical application.     

5G无线通信技术与网络安全的研究

在新背景下,无线通信技术在各个行业中得到了广泛应用,其发展水平也有了很大提升。与3G和4G无线通信技术相比,5G无线通信技术不但保留了原有的技术优势,还实现了进一步的创新与升级。5G无线通信技术的出现,不仅加快了无线网络传输速度,还能保证数据在传输过程中的准确性与安全性。文中对5G无线通信技术与网络安全进行了分析,提出了一些有效的网络安全保护措施,希望可以在一定程度上促进5G无线通信技术的发展。     

Inter Radio Access Technology [IRAT] Handover Algorithms for Heterogeneous Wireless Networks

Wireless Personal Communications - Inter-system handover is important for 4G/5G networks as these heterogeneous wireless networks (HWNs) have integrated different radio access technologies with...     

Performance Enhancement of 5G OFDM Systems Using Modified Raised Cosine Power Pulse

Wireless Personal Communications - OFDM is a key modulation technology of current wireless communication systems such as 4G LTE/LTE-A. The fifth generation (5G) of wireless cellular networks is...     

Admission control for QoS support in heterogeneous 4G wireless networks

Admission control plays a very important role in wireless systems, as it is one of the basic mechanisms for ensuring the quality of service offered to users. Based on the available network resources, it estimates the impact of adding or dropping a new session request. In both 2G and 3G systems, admission control refers to a single network. As we are moving towards heterogeneous wireless networks referred to as systems beyond 3G or 4G, admission control will need to deal with many heterogeneous networks and admit new sessions to a network that is most appropriate to supply the requested QoS. In this article we present the fundamentals of access-network-based admission control, an overview of the existing admission control algorithms for 2G and 3G networks, and finally give the design of a new admission control algorithm suitable for future 4G networks and specifically influenced by the objectives of the European WINNER project.     

对发展3G和移动宽带无线接入技术的思考

固网运营商利用已经有的宽带IP网采用IEEE 802.1 6d等宽带无线接入技术从固定向移动接入演化是明智的选择,移动运营商为发挥已经有资源的效益沿3G路线演化是必然选择,但从发展的角度看移动宽带无线接入采用无连接的分组统计复用,核心网全IP化是大势所趋.文章在介绍IEEE 802.1 6d/e、CDMA2000 1 x EV-DV的基础上,探讨了移动宽带无线接入技术的发展趋势,指出目前3G无线链路向分组化演化的基本技术和IEEE 802.1 6d/e是相同的,最终将殊途同归.文章强调指出中国的TD-SCDMA应尽快向无连接的分组统计复用方向演化.     

Radio Network Aggregation for 5G Mobile Terminals in Heterogeneous Wireless and Mobile Networks

This paper provides a novel design concept for advanced mobile multi interface terminals with radio network aggregation capability and enhanced quality of service (QoS) provisioning for multimedia services (voice, video and data) in heterogeneous wireless and mobile networks. A new module is established which provides the best QoS and lowest cost for any given multimedia service by using simultaneously all available wireless and mobile access networks for a given traffic flow. This novel adaptive QoS module with adaptive QoS routing algorithm is called advanced QoS routing algorithm (AQoSRA), which is defined independently from any existing and future radio access technology. The performance of our proposal is evaluated using simulations and analysis with multi-interface mobile stations with AQoSRA within, carrying multimedia traffic in heterogeneous mobile and wireless environment with coexistence of multiple Radio Access Technologies, such as 3G, 4G as well as future 5G radio access networks. The analysis of the proposed framework for radio networks aggregation in advanced mobile terminals has shown overall better performances regarding the achievable throughput and multimedia access probability in heterogeneous wireless and mobile environment.     

5G分场景TDD与FDD参数优化策略研究

2020年随着5G全面商用及大规模工程建设，无线网络正式进入并将长期处于“大建设、大调整、大优化”周期，2/4/5G多制式、5模13频的复杂无线网络成为常态。面对4/5G无线网络协同发展，现网存在多张网共存的格局。为不断提升用户感知，在TD-LTE E\D\F\FDD900\1800分层组网下，探索在不同场景与业务需求下，最佳的TD-LTE和LTE FDD融合组网策略。     

3G无线数据:即将破晓?

尽管3G和4G无线数据网络、服务与终端的定义一直在变,但一些早已承诺的3G功能正开始现身。同时,4G的部署则进一步延缓。     

Vertical handoffs in fourth-generation multinetwork environments

Revolutionary drivers for 4G include a push toward universal wireless access and ubiquitous computing through seamless personal and terminal mobility. One of the major challenges for seamless mobility is the criterion of a vertical handoff protocol: a handoff protocol for users that move between different types of networks. Traditional operations for handoff detection policies, decision metrics, and radio link transfer are not able to adapt to dynamic handoff criteria or react to user inputs and changing network availabilities. Nor are they able to deliver context-aware services or ensure network interoperability. Thus, new techniques are needed to manage user mobility between different types of networks. This article presents a tutorial on the design and performance issues for vertical hand-off in an envisioned multinetwork fourth-generation environment. Various network architectures and technologies for 3G and beyond are described, including wireless LANs, cellular, satellite, and Mobile IP. Then the problem of vertical handoff is defined in the context of such a diverse network environment. Finally, research efforts to resolve the open problems are explored, including new techniques for dynamic handoff decision and detection algorithms and context-aware radio link transfer.     

Challenges in the migration to 4G mobile systems

With the rapid development of wireless communication networks, it is expected that fourth-generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies including GSM, wireless LAN, and Bluetooth. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems supports comprehensive and personalized services, providing stable system performance and quality service. However, migrating current systems to 4G presents enormous challenges. In this article, these challenges are discussed under the headings of mobile station system, and service aspects. Proposed solutions to the research problems in each aspect are also examined.     

基于SIP的无线视频监控系统的设计与实现

随着3G网络的蓬勃发展,安防监控也逐渐地向传输无线化、视频高清化方向迈进。在SIP协议的基础上,结合IP网络和3G网络,设计了一种新时代的无线视频监控系统,并给出其具体设计方案,使得TD无线网络的高端数据业务可以应用于安防监控行业。     

What's right with telecom

Higher-speed wireless services are in the offing: both faster IEEE 802.11 standards and the much-maligned third-generation (3G) cellular systems, which, despite uninspiring debuts in cellphone-friendly Japan, are poised for a much better reception in coming months there and in places like China and the USA. And coming not much later will be true broadband wireless networks - pure Internet-protocol (IP) voice-capable 2-Mbit/s-and-higher data networks for which some analysts are even using the term 4G.     

Multiuser cross-layer resource allocation for video transmission over wireless networks

With the advancement of video-compression technology and the wide deployment of wireless networks, there is an increasing demand for wireless video communication services, and many design challenges remain to be overcome. In this article, we discuss how to dynamically allocate resources according to the changing environments and requirements, so as to improve the overall system performance and ensure individual quality of service (QoS). Specifically, we consider two aspects with regard to design issues: cross-layer design, which jointly optimizes resource utilization from the physical layer to the application layer, and multiuser diversity, which explores source and channel heterogeneity for different users. We study how to efficiently transmit multiple video streams, encoded by current and future video codecs, over resource-limited wireless networks such as 3G/4G cellular system and future wireless local/metropolitan area networks (WLANs/WMANs).     

6G:继续体系结构的变革

6G将是5G无线移动通信体系结构变革的延续与深化。以增强宽带与万物互联为应用驱动的网络,必然会从陆地蜂窝移动通信网向全域接入的无线通信网发展。5G开始了移动通信体系结构的变革,但还无法满足未来需求,因此它仅是变革的开端,需要不断改进。在全域接入的无线通信网中,有诸多全域接入架构技术需要6G去探索。