IMT一2000系统网络概述

简要介绍了国际电联(ITU)建议的IMT-2000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-2000家族的概念、网络的兼容和过渡及网络实现的原则和方案.     

第三代移动通信系统标准研究的现状与进展

介绍了ITU、3GPP及3GPP2有关IMT-2000标准化工作的现状及其进展情况，讨论了未来移动通信的发展方向。     

第三代移动通信技术的发展

移动通信从80年代进入人们的生活后，以每10年换一代的速度，走过了模拟话音系统和窄带数字话音系统两个阶段。在21世纪到来之际，完成了第三代移动通信系统(正式名称为IMT-2000系统)标准的制定工作，为今后十余年移动通信向多媒体数据通信的发展打下了基础。IMT-2000系统标准的发展历程与演进ITU在1996年底确定了第三代移动通信系统的基本框架，包括业务需求、工作频带、网络过渡要求和无线传输技术的评估方法等，并将FPLMTS更名为IMT-2000，其用意在于希望在2000年左右商用、最高速率达2Mb/s、工作在2GHz频段。IMT-2000的目标是…     

面向6G的星地融合标准化研究进展

星地融合被视为6G的标志性发展方向,ITU和3GPP等国际标准化组织或其它机构正有序推进面向6G的星地融合标准研发。对具有全球代表性的面向6G的星地融合标准化研究机构进行了简单介绍,重点分析ITU和3GPP在5G-Advanced及6G标准化过程中关于星地融合的主要研究和标准化成果。ITU在对卫星在IMT-2020网络的用例、场景、能力、系统、无线电接口,以及性能参数等方面进行了规范的同时,在IMT-2030未来技术趋势有关建议书突显了卫星的地位与作用。3GPP在冻结全球首个5G非陆地网络标准Rel-17、确立NR-NTN规范之后,于Rel-18版本中优化NR-NTN的同时,推出E-UTRA-NTN,并已启动Rel-19研发工作,有望在2026年启动6G标准研发。对中国IMT-2030(6G)推进组在推动6G星地融合标准化方面所做出的积极贡献一并进行了介绍,并对6G星地融合标准化工作进行了总结和展望。     

无线高速数据传输标准定立——UWC同为无线多媒体制定准则

无线通讯联盟(UWC)公布认可的UWC-136标准后，已有机构作出支援是个标准的宣布，并表示将透过DAMPSIS-136网络提供IMT-2000宽频无线多媒体通讯服务，IMT-2000即指国际流动通讯2000，乃由国际电信联盟(ITU)制订的一组标准，旨在支援第三代高速数据通讯及无线多媒体服务。     

GSM与IMT-2000互通技术的研究

简述了 IMT- 2 0 0 0的系统结构 ,分析了 IMT- 2 0 0 0家庭成员的网间直连 ,重点论述了 GSM与 IMT- 2 0 0 0间的3种互通方式和 IWF的信令协议参考模型 (S- PRM) ,最后指出了互通的重要性     

5G核心网标准化进展及B5G演进初探

为了给后续B5G核心网技术研究和标准化提供思路,首先介绍了5G核心网的服务化架构,描述了网络切片、边缘计算等关键技术;然后介绍了3GPP R15核心网标准化成果,提出了5G核心网系统架构,并介绍了R16在固移融合、5G LAN、TSN等方向的核心网标准化进展;其次介绍了ITU IMT-2020核心网标准化进展,包括IMT-2020核心网架构,给出了B5G核心网演进思路分析,提出网络极简化、行业专网增强、网络智能化、uRLLC、mMTC、天地一体化等5G核心网演进方向,并提供了3GPP、ITU的B5G核心网标准化最新进展;最后提出B5G核心网技术方案研究和标准化应覆盖全部的主流技术方向,面向未来做好技术能力储备。     

新型文本—语音软件

今年将有许多第三代（3G）移动通信网开通，这些网络支持革新性的多媒体业务，业务功能范围已超出GSM、CDMA和D-AMPS等第二代系统。这些3G网基于IMT-2000系列标准（在ITU范围内，3G系统亦称作IMT-2000系统），将在全球推广使用，亚太地区已于2001年开通，预计2002年欧洲和美洲也会开通。有这样一种设想：IMT-2000系统用户可以在世界任何地方使用IMT-2000终端，或在已开通IMT-2000网的任何国家使用这种终端，并可以在任何地方发送信息。这一理念称作全球循环，许多移动运营商认为实现全球循环是IMT-2000发展成功的关键。１全…     

IMT-Advanced频率相关问题研究进展

介绍了ITU关于IMT-2000以及IMT-Advanced系统未来发展的频率需求、候选频段等问题的研究情况及进展。     

数字蜂窝移动通信系统的多址方式与系统容量比较

现行运营的数字蜂窝移动系统中，以GSM蜂窝移动系统为主。近年来，随着数字蜂窝移动通信技术飞速发展，以及移动通信用户的增多和业务种类需求的多样化，国际电联(ITU)已着手对第三代移动通信系统(即IMT-2000)技术标准进行研究，目前．在15个提交给ITU的IMT-2000无线传输技术(RTT)标准的系统具有接通率高、     

Current IMT-2000 R&D status and views in Korea

In this article Korean development of IMT-2000 is considered. It includes the second-generation digital mobile communications, R&D and standardization activities related to IMT-2000, and the authors' perspectives on IMT-2000 in Korea. In Korea, there are many activities for development of IMT-2000 radio transmission technologies, and the results of these activities will be the submission of technologies to the ITU. However, the Korean telecommunications standardization body (TTA) will make every effort to make a common global standard for IMT-2000. Therefore, the TTA will make a domestic standard for IMT-2000 after the ITU finalizes the related Recommendations. It seems to the authors that difficulties in harmonization in the TTA are very similar to difficulties in harmonization worldwide. The only way of reaching the harmonization of IMT-2000 in Korea is that the key players should have the view from the end users' seat     

The 3GPP proposal for IMT-2000

Market expectations for third-generation mobile radio systems (IMT-2000) show an increasing demand for a wide range of services from voice to low, high, and advanced data rate services to support mobile multimedia. This leads to technical requirements for IMT-2000 which are currently being standardized worldwide. Circuit- and packet-oriented services will be supported. These systems will operate in all radio environments to provide service to anyone, anytime, anywhere. The ITU has identified spectrum for the allocation of IMT-2000. However, these frequency bands are currently not available worldwide. In different regions research activities on IMT-2000 have been initiated to support the international consensus building process and standardization activities. Based on these activities system proposals have been submitted to ITU TG 8/1. In particular, the newly formed Third Generation Partnership Projects 3GPP and 3GPP2 have the objective of harmonizing similar proposals and defining detailed standards. Proposals from Europe, Japan, Korea, and the United States are very similar. The evolution and migration of second-generation systems to the third generation takes into account the deployed investment to save today's investment where useful and necessary. This article focuses on market and technical requirements and, in particular, the technical approach of 3GPP based on the big footprint of the GSM system     

Satellite UMTS/IMT2000 W-CDMA air interfaces

The third-generation IMT-2000 initiative of the International Telecommunication Union is aiming at the provision of a limited family of global standards providing worldwide multimedia wireless services in a host of environments encompassing indoor picocells to satellite megacells. The ITU IMT-2000 initiative has been supported by several regional standardization bodies such as the European Telecommunication Standard Institute with its Universal Mobile Telecommunication System. In this article a few air interface proposals for the satellite component of UMTS/IMT-2000 based on adaptation of the emerging terrestrial wideband CDMA standards are reviewed. In particular, S-UMTS requirements are examined together with W-CDMA applicability to the satellite environment. It is shown that with minor adaptations, the terrestrial W-CDMA air interface provides an efficient solution for the satellite UMTS component. This commonality will certainly help in the realization of low-cost low-size dual-mode user terminals encompassing both terrestrial and satellite components     

UMTS/IMT-2000 based on wideband CDMA

The UMTS terrestrial radio access is based on wideband 4.096 Mchip/s DS-CDMA technology. UTRA will be connected to an evolved GSM core network for both circuit and packet services. A merger between ETSI/Europe and ARIB/Japan based on W-CDMA, a GSM core network, and a common frequency allocation according to the ITU Recommendation of 2 GHz makes a global IMT-2000 standard feasible. UTRA based on W-CDMA fully supports the UMTS/IMT-2000 requirements (e.g., support of 384 kb/s for wide-area coverage and 2 Mb/s for local coverage). Furthermore, the air interface has flexible support of mixed services, variable-rate services, and an efficient packet mode. Key W-CDMA features also include improved basic capacity/coverage performance compared to second-generation systems, full support of adaptive antenna arrays, support of hierarchical cell structures with interfrequency handover, and support of asynchronous inter-base-station operation. There have been no constraints due to the strong requirements for backward compatibility with second-generation systems. This has facilitated a high degree of flexibility and a future-proof air interface. Extensive evaluations by means of simulations and field trials have been carried out by a number of companies, and full system tests are ongoing. Consequently, W-CDMA technology can now be regarded as a mature technology, ready to provide the basis for UMTS/IMT-2000     

An overview of CDMA evolution toward wideband CDMA

Third-generation mobile radio networks, often dubbed as 3G, have been under intense research and discussion recently and will emerge around the year 2000. In the International Telecommunications Union (ITU), third generation networks are called International Mobile Telecommunications-2000 (IMT-2000), and in Europe, Universal Mobile Telecommunications System (UMTS). IMT-2000 will provide a multitude of services, especially multimedia and high-bit-rate packet data. Wideband code division multiple access (CDMA) has emerged as the mainstream air interface solution for the third-generation networks. In Europe, Japan, Korea, and the United States, wideband CDMA systems are currently being standarized. This article provides a comprehensive introduction to wideband CDMA. It also provides a review of the wideband CDMA air interface proposals including WCDMA in Europe and Japan, cdma2000 in the United States, and wideband CDMA in Korea.     

TD-LTE-Advanced国际标准历程

2000年5月,中国提交的TD-SCDMA技术被国际电联接受为IMT-2000（3G）的国际标准;2010年10月,国际电联WP5D工作组确认中国提交的TD-LTE-Advanced技术成为IMT-Ad-vanced（4G）国际标准。从TD-SCDMA到TD-LTE-Advanced,10年时间里中国已经打造了比较完整地TD产业链,并在积极推动移动通信产业的发展。     

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     

IMT-Advanced信道建模探讨

作为第四代移动通信技术,高级国际移动通信（IMT-Advanced,International Mobile Telecom Advanced）相比于第三代移动通信技术（IMT-2000,International Mobile Telecom System-200）,能够提供更高的数据速率和更好的用户体验。为了适应新的无线传播特性,国际电信联盟（ITU,International Telecommunications Union）提出了相关的测试环境和评估场景,这对开展相关技术研究,系统评估和测试具有重要的意义。IMT-Advanced信道模型的建立,相比与早期的模型更加完善,也更加准确,适于在不同场景下对无线传播特性进行分析和研究。     

IMT—2000固定无线接入技术及其应用

根据宽带接入的技术要求,在分析ＩＭＴ－２０００／ＦＷＡ技术特点的基础上,探讨它在未来宽带接入网中的两种应用方案及其在信令接口、业务质量、网络管理等方面的相关问题。