3GPP LTE标准化进展

为了保持在移动通信领域的技术及标准优势,3GPP启动其长期演进（LTE）的标准化工作。在物理层（层1）、空中接口协议结构层（层2）和网络结构方面,3GPPLTE采纳一系列先进技术和创新理念,IP语音（VoIP）业务和多媒体广播及多播业务（MBMS）的解决方案的优化正在进行中,目前已经实现高数据率、低时延和基于全分组的设计目标。     

移动宽带演进：LTE的发展路标

1向LTE演进 3GLTE（LongTermEvolution）是一个无线宽带因特网系统。它是基于TCP／IP的全IP网络,TCP／IP是因特网的核心协议,基于TCP／IP协议能提供更高等级的服务——比如语音、视频和短消息。LTE将与WCDMA和HsPA网络共存．WCDMA和HSPA网络也将在3GPP中继续演进。     

Progress of 3GPP LTE Standardization

The 3rd Generation Partnership Project (3GPP) initiated its Long Term Evolution (LTE) standardization work to retain its technology and standard advantages in the field of mobile communications. A series of advanced technologies and novel concepts related to the physical layer (Layer 1),air interface protocol structure layer (Layer 2) and network architecture are adopted. Solutions to Voice over IP (VoIP) and Multimedia Broadcast/Multicast Service (MBMS) are in the optimization process. 3GPP LTE has achieved the design goals of high data rate,low latency and an all-packet basis.     

The LTE link-layer design - [LTE part II: 3GPP release 8]

The LTE radio interface for 3GPP Release 8 was specified recently. This article describes the LTE link-layer protocols, which abstract the physical layer and adapt its characteristics to match the requirements of higher layer protocols. The LTE link-layer protocols are optimized for low delay and low overhead and are simpler than their counterparts in UTRAN. The stateof- the-art LTE protocol design is the result of a careful crosslayer approach where the protocols interact with each other efficiently. This article provides a thorough overview of this protocol stack, including the sub-layers and corresponding interactions in between them, in a manner that is more intuitive than in the respective 3GPP specifications.     

Coexistence studies for 3GPP LTE with other mobile systems - [LTE part II: 3GPP release 8]

To ensure LTE systems can coexist with other mobile systems operating in the same geographical area, or the LTE Base Station (BS) can be collocated with other mobile system BSs, coexistence studies for LTE with other systems have been carried out in 3GPP. In this article, we provide an overview of the coexistence studies that have been done. First we list the terminologies that are commonly used for coexistence studies, and explain how deterministic analysis can be done for the BS to BS interference scenario. Then we provide the system simulation methodology and assumptions used in the coexistence studies, and show some simulation results for the possible impacts with different system parameters. Finally we provide the references to the 3GPP standards where the LTE BS and UE radio transmission and reception requirements are specified to facilitate LTE coexistence with other mobile systems.     

3GPP LTE小区间干扰协调方案研究

随着3G移动通信系统逐步成熟,3GPP已经开始了对其长期演进(LTE)系统的研究和标准化工作。由于使用了新的物理层技术,使得小区间干扰抑制成为一个热点问题。针对该问题,介绍了目前小区间干扰协调/躲避研究方面的现状,对几种具有代表性的方案进行了研究,最后对各方案进行了系统级计算机仿真分析。     

3GPP组织LTE研究进展

高级国际移动电信(IMT-Advanced)是一种新概念,用于描述具有超过IMT-2000能力的新移动系统.3GPP不仅为实现IMT-Advanced而不懈工作,同时也在为实现LTE-Advanced而努力.LTE-Advanced预计会成为3GPP R10规范的一部分,IMT-Advanced可能在2013年或更晚一...     

E3G技术--3GPP LTE和3GPP2 AIE的核心技术与标准化进展

演进型3G（E3G）技术是3GPPLTE（长期演进）和3GPP2 AIE（空中接口演进）项目的统称.这项技术名为“演进”,实则是一场技术“革命”.对两种演进型3G技术--3GPP LTE和3GPP2 AIE的标准化进程、需求指标和核心技术作了简略的介绍.     

Traffic-based queue-aware scheduling for 3GPP LTE system

Although the medium access control （MAC） signaling has been well-defined in the 3rd generation partnership project （3GPP） long term evolution （LTE） specifications, the scheduling algorithm crucial to guarantee QoS performance, still remains as open issues. In this article, a traffic-based queue-aware scheduling （TQS） algorithm is proposed for evolved nodeB＇s （eNB＇s） MAC scheduler in 3GPP LTE broadband wireless networks. The proposed TQS is divided into three sub-algorithms： firstly, the authors propose a traffic model construction （TMC） algorithm which can construct a discrete-time Markov-modulated Poisson process （dMMPP） to represent each flow. Secondly, a newly traffic state estimation （TSE） algorithm is designed to obtain the queue＇s analytical statistics. Thirdly, based on the derived results of TSE and the channel states, a scheduling action decision （SAD） algorithm is presented that can adaptively allocate bandwidth to flows by considering both queue states and spectrum efficiency. Simulation shows that the TMC and TSE algorithm can capture the fluctuation of traffic and queue accurately. Moreover, compared with a widely accepted traffic-based scheduling algorithm, the proposed TQS has better average queue length and overflow probability performance.     

A Secure Relay-Assisted Handover Protocol for Proxy Mobile IPv6 in 3GPP LTE Systems

The LTE (Long Term Evolution) technologies defined by 3GPP is the last step toward the 4th generation (4G) of radio technologies designed to increase the capacity and speed of mobile telephone networks. Mobility management for supporting seamless handover is the key issue for the next generation wireless communication networks. The evolved packet core (EPC) standard adopts the proxy mobile IPv6 protocol (PMIPv6) to provide the mobility mechanisms. However, the PMIPv6 still suffers the high handoff delay and the large packet lost. Our protocol provides a new secure handover protocol to reduce handoff delay and packet lost with the assistance of relay nodes over LTE networks. In this paper, we consider the security issue when selecting relay nodes during the handoff procedure. During the relay node discovery, we extend the access network discovery and selection function (ANDSF) in 3GPP specifications to help mobile station or UE to obtain the information of relay nodes. With the aid of the relay nodes, the mobile station or UE performs the pre-handover procedure, including the security operation and the proxy binding update to significantly reduce the handover latency and packet loss. The simulation results illustrate that our proposed protocol actually achieves the performance improvements in the handoff delay time and the packet loss rate.     

认知无线电在3GPPLTE中的应用

介绍了认知无线电的概念与应用研究,在此基础上论述了将认知无线电技术应用于LTE（Long Term Evolution）系统中的必要性和可行性;讨论了认知无线电在LTE系统的无线资源管理和其自组织网络形成两个方面的应用,同时给出了相应的认知结构模型。     

未来宽带卫星移动通信系统

近些年．随着Internet的高速发展．对信息处理与传输的要求愈来愈高。作为全球通信的重要组成部分．为了顺应未来发展的趋势,全球宽带卫星通信系统概念应运而生。据不完全统计．各国提出的宽带卫星通信系统多达85个。目前正在设计中的全球宽带卫星通信系统,基本都是覆盖全球的星座系统。其中比较著名的有Teledesic．CyberStar．Spaceway系统等。本文对这三个系统进行简单的介绍。     

3GPP移动通信网络的分流技术研究

介绍了可应用于3GPP移动通信网络的分流技术方案,该方案使得数据流量能够就近疏导至Internet网络,避免核心网与接入网之间传输资源的浪费,降低了运营商网络扩容方面的压力.这为运营商网络的实际运营提供参考建议,具有重要的应用价值.     

3GPP LTE系统安全性研究

长期演进（LTE）系统代表TUMTS标准的最新发展方向,作为一种纯分组系统,它具有全新的无线接口和体系结构,其频谱效率是HSDPA／HSUPA的2倍。本文分析了LTE系统安全的主要内容,提出TLTE用户安全的体系结构,描述TIP网络的NDS体系结构,介绍了隧道模式下的ESP保护原理。     

3GPP LTE上行链路的仿真研究

在LTE系统中上行链路采用SC-FDMA方案,下行链路采用OFDMA方案。文中对LTE上行链路的物理层进行仿真研究,并深入探讨了频域均衡（FDE）技术在高速率无线通信系统中的作用。从仿真结果可以看出频域均衡技术在多径环境中显著提高了SC-FDMA链路的抗干扰性能。     

Adaptive call admission control in 3GPP LTE networks

In this article, we propose new methods to reduce the handoff blocking probability in the 3rd Generation Partnership Project Long Term Evolution wireless networks. This reduction is based on an adaptive call admission control scheme that provides QoS guarantees and gives the priority of handoff call over new call in admission. The performance results of the proposed schemes are compared with other competing methods using simulation analysis. Simulation results show the major impact on the performance of the 3rd Generation Partnership Project Long Term Evolution network, which is reflected in increased resource utilization ratio to (99%) and in the ability in satisfying the requirements of QoS in terms of call blocking probability (less than 0.0628 for Voice over IP service) and dropping probability rate (less than 0.0558).Copyright © 2012 John Wiley & Sons, Ltd.     

3GPP LTE的预编码和空间多路复用MIMO技术

当多路径信道在一个或多个MIMO接收机上无法提供足够的SINR时,3GPP LTE中的预编码技术可以极大地提高系统性能.测试结果表明,各种测量均可在多路径和信道失真条件下,对预编码系统的操作和性能进行非常有用的深入分析.     

3GPP LTE系统的切换机制研究

3GPP LTE是基于OFDM和MIMO技术对当前3G系统的中长期演进,对现有的3G系统的网络结构和无线接入方式都有较大的改进.文章详细分析了3GPP LTE所规范的切换过程,并对各大厂商提出的移动终端接入目标基站的几种方法(同步和非同步)做了比较性研究.     

3GPP LTE中Femtocell数据信道干扰管理策略

对3GPP LTE中针对家庭基站引入后的干扰场景进行了介绍,之后从频率资源和功率资源2个资源分配自由度对数据信道的干扰管理算法进行了分析,最后,对家庭基站在3GPP LTE版本10中的标准化方向进行分析。