TD-SCDMA直放站实现同步和切换的方法

随着第三代移动通信(简称3G)系统TD-SCDMA(时分同步码分多址)技术的不断成熟和3G牌照的即将发放,无线网络的建设和优化及TD-SCDMA直放站的广泛应用必不可少.本文介绍了一种简便实用的解决TD-SCDMA直放站实现同步和上下行切换的方法.     

SHARE: seamless handover architecture for 3G-WLAN roaming environment

For the transition from 3G communication systems to 4G communication systems, 3G-WLAN interworking systems can be a reference model for 4G communication systems. In this paper, we identify challenging problems in 3G-WLAN interworking systems and propose a loosely coupled architecture called SHARE. In SHARE, each WLAN hotspot access point (AP) is equipped with a 3G radio transmission module to generate radio signals for control channels of 3G networks in addition to a WLAN radio module. Consequently, base stations of the 3G networks share their control channels with hotspot APs. By monitoring these channels, mobile nodes can easily detect available WLAN hotspots without probe delay for handovers.

Handover and New Call Admission Policy Optimization for G3G Systems

Handover blocking of ongoing calls due to the mobility of users is a quantity that determines at most the Quality of Service (QoS) in microcellular and picocellular G3G systems environments. In this paper we propose a call admission policy, based on the fractional guard channel scheme, which additionally considers the blocking of new calls. Simulation results show that the proposed policy gives an improved system performance, compared to the most commonly used handover algorithms.     

3G网络与WLAN协同规划之探讨

分析了WLAN的技术特点、承载能力、应用场景;探讨了3G网络如何与WLAN协同规划;指出WLAN可作为3G网络的有效补充,和业主充分合作,在公共热点区域建设WLAN,以分流3G网络的高速数据流量,提升3G网络质量,改善用户体验;最后就如何充分发挥WLAN的作用提出了建议。     

3G网络与WLAN的综合结构设计方案

本文回顾了多种3G和WLAN相结合的网络结构,在讨论了它们的性能后提出两种新的结构设计方案,即把UMTS网络分别通过节点SGSN和GGSN接入WLAN网络.介绍了利用OPNET对这两种网络结构进行仿真的方法,并进行性能分析和比较.     

3G网络与WLAN的综合结构设计

本文回顾了多种3G和WLAN相结合的网络结构，在讨论了它们的性能后提出两种新的结构设计方案，即把UMTS网络分别通过节点SGSN和GGSN接入WLAN网络，介绍了利用OPNET对这两种网络结构进行仿真的方法，并进行性能分析和比较。     

WLAN网络建设策略及其与3G网络融合分析

文章从联通运营商WLAN业务发展的现状出发,对WLAN建设过程中存在的问题进行详细的分析和研究,根据原因提出有效的建设策略,并对3G网络的融合进行全面的阐述。     

3G与WLAN的关系

文章对无线局域网与3G的技术特点进行了比较，重点探讨了两种技术的多种网络互通方式，并对两种技术的相互关系和各自定位发表了相应意见。     

A Robust Authentication Protocol with Non-Repudiation Service for Integrating WLAN and 3G Network

The third-generation cellular systems provide great coverage, complete subscriber management and nearly universal roaming. Nevertheless, 3G systems suffer the high installation cost and low bandwidth. Though WLAN provides hot spot coverage with high data rates, it lacks roaming and mobility support. From users' points of views, the integration of WLAN and 3G systems is an attractive way that will provide them a convenient access to network. When integrating WLAN and 3G, there are still some problems should be concerned in terms of authentication and security, such as authentication efficiency and repudiation problem. In this paper, we review the authentication scheme for WLAN and 3G/UMTS interworking which is specified by 3GPP and propose a robust localized fast authentication protocol with non-repudiation service for integrating WLAN and 3G network. The localized re-authentication protocol can shorten the authentication time delay. On the other hand, with the non-repudiation service, the assumption, that subscriber has to fully trust 3G home operator, can be deleted and the trust management between the independent WLAN operator, 3G visited operator and 3G home operator can be eliminated. In other words, our proposed protocol provides legal evidences to prevent the 3G home operator from overcharge toward the subscriber and also prevent the WLAN operator and 3G visited operator from overcharge toward the 3G home operator. The authentication protocol employs HMAC, hash-chaining techniques, and public-key digital signature to achieve localized fast re-authentication and non-repudiation service.     

3G与WLAN的兼容和竞争

文章介绍了3G和WLAN的标准和技术发展现状,并分别对3G和WLAN的发展前景进行了分析;重点探讨了3G和WLAN之间竞争和兼容的关系,指出3G和WLAN技术的充分融合是未来通信发展的必然趋势。     

SDN/NFV‐based handover management approach for ultradense 5G mobile networks

With the great increase of connected devices and new types of applications, mobile networks are witnessing exponential growth of traffic volume. To meet emerging requirements, it is widely agreed that the fifth‐generation mobile network will be ultradense and heterogeneous. However, the deployment of a high number of small cells in such networks poses challenges for the mobility management, including frequent, undesired, and ping‐pong handovers, not to mention issues related to increased delay and failure of the handover process. The adoption of software‐defined networking (SDN) and network function virtualization (NFV) technologies into 5G networks offers a new way to address the above‐mentioned challenges. These technologies offer tools and mechanisms to make networks flexible, programmable, and more manageable. The SDN has global network control ability so that various functions such as the handover control can be implemented in the SDN architecture to manage the handover efficiently. In this article, we propose a Software‐Defined Handover (SDHO) solution to optimize the handover in future 5G networks. In particular, we design a Software‐Defined Handover Management Engine (SDHME) to handle the handover control mechanism in 5G ultradense networks. The SDHME is defined in the application plane of the SDN architecture, executed by the control plane to orchestrate the data plane. Simulation results demonstrate that, compared with the conventional LTE handover strategy, the proposed approach significantly reduces the handover failure ratio and handover delay.     

WLAN+3G混合组网及建设策略研究

随着3G牌照的发放,我国电信业已迎来3G时代,3G给人们带来了丰富多彩的多媒体应用.通过3G和WLAN系统的混合组网,才能充分发挥资源利用率,为用户提供高品质的数据业务支持,通过WLAN,快速而低成本地开展移动高速数据业务.     

WLAN组网及其与3G网络的融合探讨

简单地分析了WLAN的应用场景与业务定位,较详细地论述了WLAN的网络结构及组网方案,结合WLAN与3G网络融合标准对初级、中级、完全融合3个发展阶段的融合方案进行了探讨与对比分析,并对初期融合的方案采用提出了建议。     

WLAN＋3G混合组网及建设策略研究

随着3G牌照的发放．我国电信业已迎来3G时代,3G给人们带来了丰富多彩的多媒体应用。通过3G和WLAN系统的混合组网．才能充分发挥资源利用率．为用户提供高品质的数据业务支持．通过WLAN．快速而低成本地开展移动高速数据业务。     

Architecture,mobility management,and quality of service for integrated 3G and WLAN networks

Integration of 3G and wireless LAN (WLAN) becomes a trend in current and future wireless networks, and brings many benefits to both end users and service providers. In this paper, we provide a comprehensive survey on integration of 3G and WLAN. We discuss issues such as underline network architectures, integrated architectures, mobility management, and quality of service (QoS). We particularly study handoff QoS mapping and guarantee between 3G and WLAN, as well as how seamless voice/multimedia/data handoff becomes possible. Copyright © 2005 John Wiley & Sons, Ltd.     

3G与无线局域网联合组网及漫游技术分析

简要介绍了第三代移动通信网(3G)和无线局域网(WLAN)的发展现状、使用情况、各自的特点以及组网方式和漫游方式,针对两者在有效数据传输率、使用频段、覆盖范围、漫游策略和资费等方面的适用范围和互补性,在详细分析3G和WLAN联合组网漫游所具有优势的基础上,阐述了3G与WLAN联合组网和漫游的可行性,提出了一种两者联合组网和数据业务无缝漫游的实现方案,得出3G和WLAN联合组网在未来具有广泛应用前景的结论。     

Network architecture and medium access control for deploying third generation (3G) wireless systems over CATV networks

We propose a novel and cost‐effective approach for the deployment of third generation (3G) wireless systems over hybrid fiber coaxial (HFC) CATV networks. The main goal is to facilitate 3G deployment over the existing CATV plant and reduce the large cost required for building a dedicated last mile infrastructure for 3G access networks. Our proposal reduces the last mile cost by sharing the existing CATV network and using the standard equipment and protocols of data‐over‐cable systems interface specifications (DOCSIS). This allows rapid deployment of 3G wireless systems, facilitates convergence of wireless and wireline networks and paves the way towards all IP wireless networks. Enhancements to the DOCSIS medium access control (MAC) protocol must be implemented in order to support Quality of Service (QoS) guarantees for 3G data and signaling traffic. This paper presents the proposed 3G over CATV network architecture and DOCSIS medium access control (MAC) enhancements for enabling the support of QoS guarantees for 3G data and signaling traffic. The proposed MAC enhancements can reduce the access delay for delay‐sensitive traffic by 30 to 40% over existing DOCSIS MAC without compromising QoS guarantees for other traffic classes, or the DOCSIS channel utilization. Copyright © 2004 John Wiley & Sons, Ltd.     

Femtocell基站应用于3G网络的问题及解决方法

Femtocell是一种新兴的网络覆盖手段,其方便易用的特点,特别适用于增强室内覆盖,或在宏蜂窝信号不好的地方提供网络服务,可作为3G网络的补充.本文主要介绍Femtocell的基本原理及其在3G环境下的应用情况,并就频率规划、干扰、切换等面临的挑战进行了一些探讨.     

A software architecture for GPRS session management

General packet radio service (GPRS) provides efficient access to the integrated services Internet from wireless networks. When the GPRS‐attached mobile station attempts to send or receive data, a packet data protocol (PDP) context shall be established. The GPRS session management (SM) supports the PDP context handling, which consists of PDP context activation, deactivation, and modification procedures. In this paper, we propose an SM software architecture for the serving GPRS support node. Our design goals are to achieve compatibility, modularity, and flexibility. More importantly, our approach can accommodate the design of the SM software architecture for third‐generation wireless networks. Copyright © 2001 John Wiley & Sons, Ltd.     

PHS、3G和WLAN共用室内分布系统分析

介绍了PHS、3G和WLAN三个无线业务使用同一套室内分布系统实现3种信号同时覆盖;首先讨论了这三个业务各自的室内覆盖系统及其具体设计参数等;然后介绍了共用系统中有源设备的合路情况;分析了共用系统中存在的功率匹配问题,得到了相关结论。对各工作频带间的相互干扰问题做出了相关分析并给出了部分解决方案。