多业务并发模式下基于用户感知的无线网络资源优化

随着3G网络建设的日趋完善和移动数据业务的迅猛发展,3G网络承受的业务量越来越大,业务类型也越来越丰富,四网协同工作的开展使3G网络资源利用率逐步提升。由于TD-SCDMA是自干扰系统,资源利用率的提高将导致网络质量和用户感知的下降,加之3G网络数据业务与话音业务并发的特点,以及数据业务种类繁多的现状,给无线网络资源优化工作带来了极大的挑战。     

TD-SCDMA网络分流GSM网络数据业务方案

GSM/TD-SCDMA双模终端的数据业务流量"倒流"GSM网络现象严重,使得GSM网络负荷压力加大,而TD-SCDMA网络利用率偏低.本文针对上述问题,提出了网络2G/3G互操作参数调整、网络控制的2G到3GPS小区重选以及新型双模终端的综合解决方案,实现TD-SCDMA分流GSM网络数据业务,均衡2G/3G双网协调...     

全速率HSDPA:运营商的必然选择

用户需求驱动H S D P A/HSUPA发展无线数据业务发展迅速3G网络的主要特征表现在基础设备之上的业务应用,与2G不同,3G网络除了基本通话业务之外,更主要的是特色业务,包括可视电话VP、流媒体、交互式数据及背景类业务,正是3G的特色业务增加了3G网络的吸引力及竞争力。数据业务已经是无线运营商的一个主要利润来源,而且这种比例将会越来越大。根据UMTS论坛的估计,到2010年,3G业务的收益将超过3000亿美金,其中2/3的收益来自数据业务。无线数据业务对空口速率的要求越来越高,技术上也面临越来越多的问题:第一,如何提高小区的吞吐量;第二…     

增强TD-SCDMA上行能力提升移动互联体验

增强TD-SCDMA网络的上行能力,可在有限的无线带宽资源下最大限度地提升数据业务的业务质量和业务带宽,提升网络竞争力。3G网络相对于2G无线传输速率高很多,微博、手机上网等迅猛增长的数据业务要求3G网络的上下行都能提供良好支撑。目前TD-SCDMA的高速数据业务只由HSDPA和HSUPA来承载,但由于HSUPA终端的成熟度问题导致HSUPA功能仍没有规模商用,因此高速的数据业务下行可以使用HSDPA,但是上行只能使用R4的DCH信道承载。现有TD-SCDMA网络的小区时隙配置一般为2:4,因此上行带宽资源(DCH)非常容易受限。     

需求三完善的室内覆盖网络

TD-SCDMA工作的核心频段为2GHz频段,与2G网络工作的900MHz频段相比,TD-SCDMA的穿透能力相对较差,在室内环境下将形成更多的覆盖不足区域.同时,随着TD-SCDMA网络的逐步完善,大量的3G数据业务出现在室内环境中,这对室内覆盖提出了更高的要求.     

1880～1900MHz频段的引入及其对TD-SCDMA网络的影响

为充分发挥TD-SCDMA在数据业务支持方面的优势,中国移动将TD-SCDMA网络主要定位于承载数据业务。随着试验网业务的发展,频率资源日趋紧张,最初使用的2 010～2 025 MHz频段已逐渐不能满足业务开展的需要。2009年1月,随着3G牌照的发放,1 880～1 900 MHz被分配给中国移动作为TD-SCDMA网络运行的频率使用。本文对引入1 880～1 920 MHz频段后对TD-SCDMA网络的影响进行了探讨。     

杭州移动F频段TD-LTE网络规划探讨

1 网络规划思路 中国移动TD-LTE网络是TD-SCDMA网络未来演进发展的方向。TD-SCDMA是GSM网络流量的“分流”渠道,主要承载手机数据业务,并分流GSM话音业务,且未来要继续扩大3G智能机用户规模。TD-LTE网络是用户数据业务需求的“泄洪”渠道,是未来高带宽、高质量无线宽带业务的主力承载网。     

TD-SCDMA网络HSDPA引入后的组网策略分析

HSDPA的引入将进一步增强TD-SCDMA网络下行数据传输速率.本文分析了TD-SCDMA网络中HSDPA技术特点并比较了与WCDMA HSDPA技术的异同,同时结合产业成熟程度以及3G数据业务的发展状况给出TD-SCDMA网络中HSDPA引入后的组网策略建议.     

3G接入网支持高速数据时对传输流量的估算

2G移动通信系统主要是GSM系统和窄带CDMA系统。3G移动通信主要以TD-SCDMA、WCDMA、cdma2000三大主流标准为主,在这三种标准基础上发展的高速数据业务中,cdma2000对应的是cdma2000 1x EV-DO（1x增强型数据业务）,WCDMA和TD-SCDMA对应的是HSDPA（高速下行分组数据业务）。目前这些技术在国内都建有实验网。3G传输网作为电信网的基础网络,其建设和应用在整个3G网络发展中扮演着重要的角色。     

基于TD-SCDMA的HSDPA系统性能仿真研究

基于用户对高速分组数据业务的需求,3GPP在R5引入了HSDPA(FDD、TDD)技术.在国外已经运营的WCDMA网络中,HSDPA的引入确实大大提高了下行数据速率,而国内正在规模建设中的TD-SCDMA实验网络也将逐步引入HSDPA,充分体现出3G在数据业务上的优势.主要通过理论分析结合系统仿真的手段来考察基于TD-SCDMA的HSDPA系统网络的性能,作为实际网络规划的参考.     

我国移动通信网从第二代到第三代的演进策略

随着第三代移动通信标准的日趋成熟,其产品预计可在2004年前后投入商用。本文在分析市场需求、技术发展现状和保护已有设备投资的基础上,从保证我国移动通信产业、运营商和移动用户利益出发提出：第一步,在IMT－2000核心网成熟之前,采用现有的GSM／GPRS核心网,通过A和Gb接口提供话音和数据业务;空中接口采用频谱利用率高、符合IMT2000要求的TD－SCDMA技术,以满足高话务量区域的需求。第二步,采用成熟的IMT-2000核心网（Release2000)、IMT2000FDD和TD－SCDMA无线传输技术,逐步形成第三代移动通信系统。     

TDD-CDMA for the 4th generation of wireless communications

This article discusses an evolutionary TDD mode of CDMA-based path for 3.5G/4G systems. This technology has already been the basis of two 3G standards: TD-CDMA and TD-SCDMA with a synchronous uplink. Several techniques have been developed that allow TDD-CDMA-based systems to transmit at rates usually associated with 3.5G to 4G, up to 10-20 Mbit/s with wide area coverage. The present TDD-CDMA-based 3G standards are evolving to provide these higher rates, while fully retaining the coverage and mobility associated with, and expected from, the present mobile communications systems. This article discusses how TDD-CDMA specific techniques facilitate delivering services at data rates associated with 3.5G and 4G. We review how TDD-CDMA can provide for asymmetric uplink and downlink transmissions, facilitate deployment of advanced antennas for improved downlink coverage, and enable provision of advanced receiver techniques in base stations and mobiles. We also discuss how these techniques affect systems capacity in full packet-switched IP-based systems. We then discuss 4G TDD CDMA systems: those with different modulation techniques for uplink and downlink communications. These are generally based on a multicarrier mode of CDMA, and may incorporate OFDM technique.     

TD室内覆盖技术及应用

随着3G对数据业务的强劲支持,室内业务占整网的比重迅速提升,在TD网络的建设和规划中,更需要一种灵活的室内覆盖解决方案。本文借助中兴通讯的室内覆盖产品,结合工作的实际,对TD的室内覆盖特点、“多通道”室内覆盖技术的实现给予了分析,并对该技术的实际应用给出了案例。     

The role of high altitude platforms in beyond 3G networks

High altitude platforms represent a new alternative to terrestrial and satellite communications systems, and have gained considerable interest in the past few years due to some of their outstanding features. Of the multitude of services HAPs can provide, in this article we, focus on the potential role of HAPs in beyond 3G networks. First, a short introduction to HAPs is made. Then we discuss different hybrid system architectures with emphasis on the merits of HAPs and provide a potential mapping of services to the components of a terrestrial-HAP-satellite integrated system. We also examine critical issues that stem from the use of HAPs. Finally, the maximum uplink capacity is evaluated for a multiservice W-CDMA HAP network.     

Cell Planning in WCDMA Networks for Service Specific Coverage and Load Balancing

Third-generation (3G) Wideband Code Division Multiple Access network is an evolutionary network which supports services from circuit-based voice service to high and low rate packet-based data services. Unlike the voice oriented second-generation service, the 3G network is enhanced to support services with different data rate, different asymmetry, and different coverage. We thus need to investigate the coverage of multiple services and the capacity of a cell in cell planning for the advanced network. Service specific uplink coverage and downlink capacity with load balancing are considered in our cell planning. The problem is formulated as a linear integer programming optimization model. An efficient tabu search heuristic is developed to solve the NP-hard problem. Very promising computational results are demonstrated, where the solution gap from the optimal to the lower bound by CPLEX is within 0.9% in problems to cover all service traffic in the system. It is demonstrated that higher load factor effectively reduces cell sites for multiple service classes. Load balancing among cells is also demonstrated with different coverage ratio.     

LTE系统上行链路质量提升的方法研究

随着VoLTE业务的商用以及4G用户大规模增加，4G网络不仅承担数据业务，还承担着语音业务，这对上行链路质量提出了更高的要求。在网络结构和无线环境日趋复杂的情况下，LTE链路质量在很大程度上制约着LTE网络性能的发挥，LTE网络受干扰、覆盖或容量受限程度直接影响了通话质量、上传下载速率、业务时延等用户的实际感知，还会引起无法接通、掉话、切换失败等一系列问题事件。本文利用功率余量值PH表征LTE上行链路质量，通过挖掘并调整上行性能参数来快速的提升上行链路质量。结合上海核心城区低功率余量TOP小区的实际情况，探究上海低PHR小区占比高的主要原因，提出一套区别于传统优化方式的参数优化方案以实现低PHR小区占比降低，达到上行链路质量提升的目的。通过试点验证可知，目前核心城区上行低PHR问题小区占比已由3.94%降至1.48%。     

TG分流提升TD-SCDMA网络利用率

三大TG分流措施提升TD-SCDMA网络利用率：适当提升PCCPCH功率改善TD覆盖。23G互操作参数精细优化,使用户尽量驻留在TD。采用新技术,保证客户感知,引入基于IMEI的分组切换算法和基于上行链路质量的切换算法两项新技术。     

Impact of imperfect power control multiuser detection on the uplink of a WCDMA high altitude platform system

Within the broad field of communications, considerable interest has been drawn towards High Altitude Platforms (HAPs) the past few years owing to their appealing features. Among the multitude of services that HAP systems are able to provide, HAPs have the potential to deliver 3G communication services. In this letter, we examine the impact of both imperfect power control and multiuser detection (MUD) on the uplink of a WCDMA HAP system.     

面向5G的小蜂窝网络研究综述

超密集组网的小蜂窝网络将是解决人们对更高无线通信服务需求的重要技术。总结了5G的发展愿景及对应的关键技术,分析了小蜂窝网络在未来无线通信系统中所承担的重要作用和面临的挑战,并给出了对应的解决思路,提出了解决认知小蜂窝网络与宏网络共存时上/下行通信所面临问题的解决方案。相关内容和建议可为小蜂窝网络的进一步发展提供明确的参考。     

A CDMA wireless packet network for voice-data transmissions

This letter investigates the possibility of integrating voice and data communications in a CDMA wireless packet network to provide access to a base station over a common short-range radio uplink channel for many spatially dispersed voice and data user terminals. Speech activity detection is assumed for voice communications to temporarily devote codes unused by voice user terminals during silence periods to data transmissions. The network proposed exhibits a good performance both in terms of quality of voice communications which is independent of data transmissions and maximum data traffic load supported with bounded delay