3G/IMT-2000的移动性管理分析

第三代移动通信系统(3G)的重要特点是支持覆盖全球的综合多媒体业务,包括高速到低速移动、室外到室内的各种系统运营环境.由于它的全球性服务与全球性网络设计,3G的移动性管理成为近年发展迅速热点研究领域之一.本文对3G分层系统的移动性管理进行分析,提出优化步骤并进行讨论,得出3G分层系统较3G单层系统性能要好.     

第三代移动通信的频率和牌照问题

介绍了ITU对IMT－2000频率的分配建议和欧、美、亚洲一些国家在频率分配上的实际情况,详细介绍了这些国家3G牌照发放政策和情况。     

The design policy for a GSM-based IMT-2000 network

The third-generation mobile network has been a topic of considerable interest worldwide and has begun to be commercialized throughout the world. The 3G mobile network has evolved from two types of 2G networks; one type has evolved from GSM and another from ANSI-41. We operate the Personal Digital Cellular network as a 2G network and have designed a GSM-based IMT-2000 network as a 3G network. This article gives our design policy for the GSM-based IMT-2000 network and the technology that enabled us to develop the network based on this policy (e.g., ATM switching in the core network). Furthermore, the foundations for 2G/3G dual network operation (e.g., number portability and succession of 2G services in a 3G network) and efficient transition from a 2G network to a 3G network are also considered.     

IMT-2000无线通信标准

国际无线通信联盟（ＩＴＵ）于去年 １１月在赫尔辛基会议上最终确立了ＩＭＴ－２０００标准。在不偏袒现有任何一个协议的情况下，这一协议为所有主要的无线通信协议提供了统一的３Ｇ（第三代）无线通信平台。有了ＩＭＴ－２０００标准，互相竞争的无线通信技术将在３Ｇ世界里共存，并可在一个框架下做到互相连接。 两年多来，无线系统供应商一直在为适用于第三代（３Ｇ）无线通信网络的最好平台争吵。一个无线平台的主要结构层包括一个基础的核心网络和相应编码、处理、传输的无线通信协议。为满足目前手机、ＰＤＡ（个人数字助理）和其它…     

IMT-2000 core network node systems

The IMT-2000 third-generation network system has been operating in the Japanese market since May 2001. In order to provide value added phone services including CAMEL services, a layered call control architecture has been developed. This architecture could achieve smooth core network migration from 2G to 3G. This system provides MSC/VLR, SGSN, and GGSN functionalities based on ATM technology.     

The current situation of IMT-2000 standardization activities inJapan

This article provides an overview of the current IMT-2000 standardization activities in Japan. This article includes three main points, namely a guideline for introducing IMT-2000 into the Japanese market, radio transmission technology and an outline of the proposal to ITU-R, and key issues of network aspects     

Dielectric resonator antenna for dual-band PCS/IMT-2000

A novel broadband and small dielectric resonator antenna has been investigated experimentally and numerically. A bandwidth of 25% has been achieved, and an omni-directional radiation pattern obtained. These features make such antennas highly suitable for application to mobile handsets     

Small internal ceramic chip antenna for IMT-2000 handsets

A small internal ceramic chip antenna for IMT-2000 handsets is investigated experimentally and numerically. It has a bandwidth of about 14%, measured gain of 1.3 dBi, and an omnidirectional radiation pattern similar to that of a monopole antenna. These features make the proposed antenna suitable for handset applications.     

IMT-2000的融合、演进新进展

论述了有关IMT-2000的融合、演进新进展。     

超3G研究的最新进展

超3G在ITU—R范围内的各项研究工作还刚刚开始．基本上还处于制定工作计划的阶段。但目前关于对超3G频率需求计算方法的研究．已经有一些国家提出了自己的建议，主要是日本和德国。超3G研究工作。特别是频谱计算、业务预制、新的无线接入和核心网技术方面研究工作的开展，对我国的研究机构、相关公司和高校都是一个继续赶超世界先进通信技术．获取成果的绝好机会。     

Current development of IMT-2000 in China

This article describes the current development of mobile communications in China, including market demand, operators, and technologies. The reasons China put great emphasis on IMT-2000 research and development are discussed. An IMT-2000-related organization structure is given, and their different responsibility and latest progress are also described. Finally, the author gives some viewpoints on IMT-2000     

IMT—2000系统网络概述

简要介绍了国际电联 (ITU)建议的 IMT- 2 0 0 0网络技术方面的特点 ,以及 ITU的相关建议制订情况 ,阐述了IMT- 2 0 0 0家族的概念、网络的兼容和过渡及网络实现的原则和方案。     

The cellular phone industry in Malaysia: toward IMT-2000

Explosive growth of the cellular phone industry in Malaysia has been witnessed in the 1990s. Eight nationwide cellular phone operators with different technology bases exist in a single market. This article provides an overview of the telecommunications industry, especially the cellular phone sector, and also the activities on IMT-2000 in Malaysia     

基于CDMA的IMT-2000空中接口方案简介

围绕第三代移动通信系统IMT - 2 0 0 0标准 ,各国间正展开激烈的竞争 ,提交ITU的地面候选方案多达 10种。由于CDMA具有容量大、频谱利用率高、频率规划方便等优点 ,IMT - 2 0 0 0候选标准已基本上统一到基于CDMA方案上。本文先简要介绍了第三代CDMA空中接口的特征 ,然后分别介绍呼声最高的两种方案的空中接口标准 :W -CDMA和cdma2 0 0 0。     

基于CDMA的IMT-2000空中接口

首先介绍了第三代CDMA空中接口方案的特征,然后对WCDMA和cdma2000这两种方案进行了比较。     

Wide-band CDMA for the UMTS/IMT-2000 satellite component

This paper describes the main aspects relevant to the development of a third-generation radio transmission technology (RTT) concept identified as satellite wide-band CDMA (SW-CDMA), which has been accepted by the International Telecommunications Union (ITU) as one of the possible RTTs for the satellite component of International Mobile Telecommunications-2000 (IMT-2000). The main outcomes of the extensive system engineering effort that has led to the above ITU RTT are described. In particular, we address propagation channel characteristics, satellite diversity, power control, pilot channel, code acquisition, digital modulation and spreading format, interference mitigation, and resource allocation. Due to its similarity with respect to the terrestrial W-CDMA proposal from which it is derived, the SW-CDMA open air interface solution is described briefly, with emphasis only on the major adaptation required to best cope with the satellite environment. Quantitative results concerning the physical-layer performance over realistic channel conditions, for both forward and reverse link, are reported. A system capacity study case for a low-Earth-orbit constellation is also provided     

Mobile IP-DECT internetworking architecture supporting IMT-2000applications

Realistic realization and mass acceptance of mobile data services require networking architectures offering acceptable quality of service and attractive tariffs. A novel strategy for this goal is maximum integration of popular data networking standards and their infrastructure into wireless networks. This article discusses a Mobile IP-based network architecture to provide IP services in DECT to support IMT-2000 applications. DECT offers micromobility within multicell subnets, while Mobile IP supports macromobility between multicell subnets. Incorporating Mobile IP into the DECT handoff mechanism in this way extends DECT micromobility with IP macromobility. Also, utilizing fast, seamless DECT handoff management reduces Mobile IP handoff delay to circumvent TCP throughput degradation during handoff and reduce frequency of Mobile IP signaling over the ether to conserve spectral efficiency. This feature seamlessly unifies DECT with the global Internet. Seamless integration of DECT with the Internet is crucial due to the continuing phenomenal popularity of the Internet and wireless communications, and ubiquity of DECT systems. To achieve the above DECT/IP interworking efficiently, the architecture introduces a network entity called a DECT service switching point, which is an extended DECT central control fixed part. DECT network-level services are mapped onto those of the IETF integrated services architecture to maintain QoS provided by DECT in the backbone Internet. Mobile Resource Reservation Protocol, an extended RSVP tailored to mobile networking, is adopted to provide the needed signaling in IntServ. The proposed architecture preserves traditional non-IP based services such as PSTN voice     

移动通信后3G或4G技术前景探索

对移动通信前20余年的发展略予回顾，指出其现状差强人意之处。阐述了当前世界各国相关业界对于新一代移动通信技术发展的一些要求、设想和探讨。     

多用户检测算法及其在IMT-2000中的应用

本文研究了应用于CDMA移动通信系统的各种多用户检测算法的原理和优缺点。首先指出多用户检测技术主要分为线性多用户检测和干扰对消多用户检测两类，然后对各类多用户检测技术的特点进行了分析比较。最后，探讨了用软件无线电实现多用户检测的可行性。