首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
介绍了中兴GoTa移动集群调度系统,较详细地描述了调度服务系统(DSS)和基站系统(BSS)各功能实体以及可实现的业务功能,全面讨论了中兴GoTa移动集群调度系统的优势.  相似文献   

2.
Important aspects of mobility and security in the Global System for Mobile communications (GSM) system are discussed in this paper. Mobility management functions are broadly categorized into three groups: a) mobile turned on, b) mobile turned off, and c) mobile in conversation. The paper first outlines the mobile synchronization sequence followed by its mobility functions: mobile identification, authentication, international mobile station identity attach/detach, and its location update. The important role of security in the GSM system is fully explored, including authentication, encryption, and positive identification of mobile equipment before the user is provided with the service. The future of mobility management with respect to subscriber identification module roaming, intersystem roaming, advancement in mobile service, and its impact on data base requirements, is covered  相似文献   

3.
随着移动互联网业务的迅速发展,位置服务需求越来越多样化,定位技术也变得越来越重要.LTE(long term evolution)室内蜂窝网络可以解决GPS(global positioning system)信号无法进入室内的问题,从而提供高精度的位置服务.LTE室内定位需要不同基站之间进行精确同步,这给室内网络部署带来了新的挑战.针对上述问题,提出了一种基于多天线簇的LTE新型无线定位系统,通过上行探测参考信号(sounding referencesignal,SRS)获取信号到达时间差(time difference of arrival,TDOA).该方法不需要簇间同步,可有效降低网络部署难度.其次,针对此系统设计了一种新的TDOA定位算法,可支持灵活的天线簇配置.最后,通过仿真及实验验证了该定位系统及算法的有效性,实验结果表明可实现米级室内定位精度.  相似文献   

4.
基于RFID技术的小额支付系统的设计   总被引:2,自引:0,他引:2  
杨小妹  申敏 《世界电信》2006,19(4):54-57
作为一种移动数据业务,移动小额支付业务已经走进人们的生活,成为大家关注的焦点,也必将成为移动运营商竞争的一个领域.基于射频识别(RFID)的核心技术,针对当前小额支付系统的现状,提出了基于RFID技术的小额支付系统的优化设计方案,并对系统结构、业务流程和安全性等方面做了详细的阐述.  相似文献   

5.
A variety of land mobile radio systems are compared by their spectral and economic efficiencies in providing various user services, system types covered are private one-channel, shared repeater one channel, controlled-access one-channel, trunked multichannel, and cellular. Spectral efficiency is defined to be the number of mobile users that can be served per MHz of spectrum in a core urban area, while economic efficiency is the average system cost per mobile. Both efficiencies vary with the type of usage, hence they are calculated for three major usages-mobile telephone service, dispatch service emergency, and dispatch service nonemergency. Services are described via seven "service parameters," namely call holding time (average), tolerable average wait for channel access, peak busy hour utilization per mobile, audio quality (S/N), noise levels tolerable, and service range. Sensitivity of the basic results to variations in the service parameters are also computed and discussed.  相似文献   

6.
Rapid advances in wireless mobile network technologies and mobile handsets (MHs) facilitate ubiquitous infrastructure that can support a range of mobile services and applications in addition to conventional mobile Internet access. One recent trend is to effectively run desktop PC-oriented heavier applications on MHs. However, due to their miniature, portable size, MHs are resource-constrained and therefore, running these applications directly on an MH is not satisfactory given a user's expectations. To cope with this problem, this article proposes a novel offloading service that can seamlessly offload some of the tasks of a mobile application from an MH to nearby, resource-rich PCs (called surrogates). The system architecture and key components of the proposed offloading service are presented, prototyped, and evaluated. The results of experiments and simulations have demonstrated the effectiveness and efficiency of this offloading service for mobile applications.  相似文献   

7.
新一代移动通信综合业务信息服务系统   总被引:2,自引:0,他引:2  
高欣 《电信快报》2000,(8):15-20
无线应用协议 (WAP)融合了因特网技术与移动通信技术的优势 ,成为事实上的业界标准。基于WAP技术提供无线信息服务已成为目前移动通信与信息行业新的业务增长点。文章通过对WAP技术及其应用现状的分析 ,提出新一代移动通信综合业务信息服务系统解决方案。该系统将运营商优势与WAP技术充分结合 ,实现符合当前无线应用需求的运营模式和体系结构。  相似文献   

8.
9.
Interference scenarios and methodologies between a terrestrial mobile service (MS) system and mobile‐satellite service (MSS) system in a co‐channel environment are established. Taking into account a practical deployment situation for both systems, we perform computational simulation of interference in terms of carrier‐to‐interference ratio (C/I) and interference‐to‐noise ratio (I/N) to evaluate the cofrequency interference from an MS system into an MSS system, and from an MSS system into an MS system, respectively. The methodology and results can be used as a guide when planning the deployment of MSS and MS systems with no unacceptable interference impact between them.  相似文献   

10.
While speech services in mobile communication systems are investigated quite well, video telephony services are relatively novel in this sector. Because of the market penetration of camera equipped mobile phones the video telephony service is expected to become a widely used service. In this article an introduction of the protocols used for video telephony in UMTS is given. Concepts for the performance evaluation in terms of video (PEVQ) and audio quality (PESQ) are presented and utilized. Evaluations are performed by both live measurements and network emulation. The results show that there is quite potential for improvements related to video telephony in UMTS in terms of video quality and channel setup time. Finally, an improved radio bearer configuration is provided which aims at a better integration of video telephony services into the UMTS architecture.  相似文献   

11.
To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services.  相似文献   

12.
We investigate the notion of per-user integrated location and service management in personal communication service (PCS) networks by which a per-user service proxy is created to serve as a gateway between the mobile user and all client-server applications engaged by the mobile user. The service proxy is always colocated with the mobile user's location database such that whenever the MU's location database moves during a location handoff, a service handoff also ensues to colocate the service proxy with the location database. This allows the proxy to know the location of the mobile user all the time to reduce the network communication cost for service delivery. We investigate four integrated location and service management schemes. Our results show that the centralized scheme performs the best when the mobile user's SMR (service to mobility ratio) is low and CMR (call to mobility ratio) is high, while the fully distributed scheme performs the best when both SMR and CMR are high. In all other conditions, the dynamic anchor scheme is the best except when the service context transfer cost is high, under which the static anchor scheme performs the best. Through analytical and simulation results, we demonstrate that different users with vastly different mobility and service patterns should adopt different integrated location and service management methods to optimize system performance. Further, the best integrated scheme always performs better than the best decoupled scheme that considers location and service managements separately and management schemes that do not use any service proxy.  相似文献   

13.
基于MBMS的手机电视技术   总被引:1,自引:0,他引:1  
多媒体广播组播业务(MBMS)是3GPP Release 6版本中引入的一项重大功能,目的在于节省系统资源,为用户提供广播或者组播的分组数据业务.作为一种具体的MBMS应用,手机电视技术在3G业务中占有重要的地位.文中介绍了多媒体广播和组播技术(MBMS),包括MBMS的网络结构、业务流程以及基于TD-SCDMA的MBMS系统架构,对LTE中的E-MBMS技术进行了初步研究,并从逻辑结构、业务模式和信道结构等方面简单分析了从MBMS到E-MBMS的演进.  相似文献   

14.
A hybrid location finding technique based on time difference of arrival (TDOA) with round‐trip time (RTT) measurements is proposed for a wideband code division multiple access (WCDMA) network. In this technique, a mobile station measures timing from at least three base stations using user equipment receive—transmit (UE Rx—Tx) time difference and at least three base stations measure timing from the mobile station using RTT. The timing measurements of mobile and base stations are then combined to solve for both the location of the mobile and the synchronization offset between base stations. A software‐only geolocation system based on the above mobile/base stations timing measurements is implemented in Matlab platform and the performance of the system is investigated using large‐scale propagation models. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

15.
USSD网关及其移动接口的设计与实现   总被引:1,自引:0,他引:1  
非结构化补充数据业务(USSD),是一种基于全球移动通信系统(GSM)网络的新型交互式数据业务.USSD系统采用面向连接的交互式会话方式,是会话类业务的理想载体.文中首先分析了USSD中的信令及移动台与USSD网关的信令交互过程,然后描述了USSD网关的系统结构,最后给出了USSD网关的移动接口设计方案,并给出具体实现过程.  相似文献   

16.
第三代移动通信技术的现状和展望   总被引:4,自引:0,他引:4  
吴更石  杨平 《电信科学》2001,17(4):28-31
本文首先分析了第三代移动通信未来的业务和市场。回顾了第三代移动通信协议的标准化进程,分析了几种主流的第三代移动通信技术的特点和优势,特别分析了第三代移动通信标准化工作的最新内容和未来移动通信的可能发展方向,最后介绍了中国移动通信设备商在第三代移动通信设备研制和生产上的进展。  相似文献   

17.
移动电话内容服务系统的设计与实现   总被引:1,自引:0,他引:1  
移动电话内容服务系统允许移动用户通过移动互联技术浏览、购买和下载系统内容,是当前移动增值领域研究的热点。文中介绍了一个基于WEB和WAP技术的移动电话内容服务系统的设计与实现.并对系统的基本框架结构和主要功能模块进行了详细介绍。最后介绍了系统实现所采用的几项关键技术。  相似文献   

18.
19.
区域性卫星移动通信系统对于发展中国家具有十分重要的意义,特别是对于中国这样幅员辽阔且在广大农村地区缺乏基本通信手段的国家.采用中轨星座是解决这一问题的有效途径.本文提出了一种用于区域性系统的中轨星座设计方法:"时间决定"星座设计.该星座可为特定地区提供性能优越的服务,它提供的服务可以是时限的,也可以是非时限的.利用这种设计方法可以为中国设计经济的卫星移动通信系统星座方案,同时这些星座方案也可为美国大陆提供优越的服务.  相似文献   

20.
A variety of land mobile radio systems are compared by their spectral and economic efficiencies in providing various user services. System types covered are private one-channel, shared repeater one channel, controlled-access one-channel, trunked multi-channel, and cellular. Spectral efficiency is defined to be the number of mobile users that can be served per MHz of spectrum in a core urban area, while economic efficiency is the average system cost per mobile. Both efficiencies vary with the type of usage, hence they are calculated for three major usages-mobile telephone service, dispatch service emergency, and dispatch service nonemergency. Services are described via seven "service parameters," namely call holding time (average), tolerable average wait for channel access, peak busy hour utilization per mobile, audio quality (S/N), noise levels tolerable, and service range. Sensitivity of the basic results to variations in the service parameters are also computed and discussed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号