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1.
With the advent of IP technologies and the tremendous growth in data traffic, the wireless industry is evolving its core networks toward IP technology. Enabling wireless Internet access is one of the upcoming challenges for mobile radio network operators. The General Packet Radio Service is the packet-switched extension of GSM and was developed to facilitate access to IP-based services better than existing circuit-switched services provided by GSM. We illustrate how a visited mobile subscriber on a GPRS/UMTS network can access his/her home network via the gateway GPRS support node (GGSN). We also propose some implementation ideas on wireless Internet access for a remote mobile subscriber based on a GPRS/UMTS network  相似文献   

2.
Wireless LAN access network architecture for mobile operators   总被引:16,自引:0,他引:16  
The evolution of IP-based office applications has created a strong demand for public wireless broadband access technology offering capacity far beyond current cellular systems. Wireless LAN access technology provides a perfect broadband complement for the operators' existing GSM and GPRS services in an indoor environment. Most commercial public wireless LAN solutions have only modest authentication and roaming capability compared to traditional cellular networks. This article describes a new wireless LAN system architecture that combines the WLAN radio access technology with mobile operators' SIM-based subscriber management functions and roaming infrastructure. In the defined system the WLAN access is authenticated and charged using GSM SIM. This solution supports roaming between cellular and WLAN access networks and is the first step toward an all-IP network architecture. The proto-type has been implemented and publicly verified in a real mobile operator network  相似文献   

3.
Mobile phones are becoming pervasively used to access Internet and multimedia contents due to their increasing processing power and its wide range of featured wireless communication technologies (Infrared, Bluetooth, NFC, GSM, UMTS, HSPA, WiMax, LTE). In this paper we also introduce mobile devices as a pervasive testbed platform to characterize the energy consumption profile of Internet services. The most innovative advantage provided by our solution is the testbed’s flexibility and simplicity, making it possible to carry out extensive testing campaigns using actual mobile devices in live networks with real services.  相似文献   

4.
Several of the emerging mobile commerce services, such as mobile auctions, mobile financial services, and multi‐party interactive games, will require support for dependable transactions. This is a difficult challenge because of both intermittent connectivity and potential failures in wireless infrastructure. In this paper, we present a multi‐network access‐based wireless architecture and related protocols to support dependable transactions. The key idea is to allow group users to utilize access to one or more wireless networks to complete different steps of a transaction. This allows for transactions to be completed even under time‐ and location‐dependent connectivity problems and network failures. The performance results show that access to multiple wireless networks leads to very high transaction completion probability even when individual wireless networks do not offer continuous and/or highly available access. The transaction completion probability is found to be dependent on the group size and number of steps in a transaction, and the same level of dependable performance for transactions can be achieved by increasing the number of wireless networks or improved access to individual networks. The overhead for multi‐network access can be further reduced by creating preferred wireless networks and by reducing the number of critical users in different transaction stages. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

5.
Digital wireless local loop system   总被引:2,自引:0,他引:2  
The digital access technologies for the wireless local loop (WLL) or fixed wireless system are discussed. WLL is an important means of providing telephone services more cheaply and quickly in the developing countries than through a wireline system. Capacities of a WLL system based on the IS-54 (now IS-136) TDMA, IS-95A CDMA, and ETSI GSM technologies are developed and compared  相似文献   

6.
在我国,中国移动已成为全球为数不多的几个同时拥有固定网络与移动网络的大运营商之一,如何充分利用固定网络资源与移动网络资源成为了全球通信业界研究的热点之一。本平台的目标是利用UMA技术有效的将Wi-Fi网络与TD-SCDMA网络和GSM网络结合在一起,实现三网融合,将话音业务和数据业务进行分流;由一个具有自主开发产权的UMA控制器(UNC)和双模手机构成。在不影响现有移动网络的基础上,通过增加UMA控制器,双模手机能够通过Wi-Fi网络无缝接入移动通信网络,实现WLAN、TD-SCDMA网络和GSM网络相互切换、漫游、无线上网等功能,移动用户不需改变号码即可享受该功能。  相似文献   

7.
家庭智能化网络监控系统的设计   总被引:1,自引:0,他引:1  
针对目前家庭住宅人身财产的安全,设计了一种基于单片机为控制核心,通过全球移动通信系统(GSM,Global System For Mobile Communications)无线移动网络与公用电话网络,实现远程自动监控报警控制的系统。该设计是以GSM移动网络与公用电话网络为媒介,通过手机用户、电话用户实现对远程住宅设备的控制及信息采集。重点阐述了GSM模块、双音多频(DTMF,Dual Tone Multi Frequency)检测发生模块的硬件设计原理及应用。介绍了MT8880芯片与GSM模块的连接及实现原理。实际应用说明了该设计系统稳定、可靠、成本低廉。  相似文献   

8.
安全控制管理中心通过蜂窝移动通信网络,可构建蜂窝移动通信安全服务系统,为专用手机提供安全信息自动产生和分配、被动式和主动式安全信息销毁、安全数据控制以及失控专用手机追踪等安全通信管理服务,确保专用手机的使用、操作安全。论文提出专用手机利用在GSM提供的数据信道上建立的虚拟专网(VPN)来实现数字安全话音和安全数据通信,适合在国内外现有的GSM蜂窝移动通信系统上使用。  相似文献   

9.
The forthcoming mobile communication systems are expected to provide a wide variety of services, from high-quality voice to high-definition videos, through high data rate wireless channels anywhere in the world. The high data rate requires broad frequency bands, and sufficient broadband can be achieved in higher frequency bands such as microwave, Ka-band, and millimeter-wave. Broadband wireless channels have to be connected to broadband fixed networks such as the Internet and local area networks. The future-generation systems will include not only cellular phones, but also many new types of communication systems such as broadband wireless access systems, millimeter-wave LANs, intelligent transport systems, and high altitude stratospheric platform station systems. Key to the future generations of mobile communications are multimedia communications, wireless access to broadband fixed networks, and seamless roaming among different systems. This article discusses future-generation mobile communication systems.  相似文献   

10.
Recently, mobile networks and internet technologies have been widely developed for the voice communication and information retrieval services all over the world. Compared with the wire‐line internet environment, mobile networks have lower bandwidth, longer transmission latency and unreliable connection, and the capability of mobile terminals is restricted by the limited memory size, lower CPU computation capability and inconvenient I/O interface. These limitations restrict the development of the wireless internet applications. In this paper, we design and implement a ‘wireless internet remote access platform’ (WIRAP). The WIRAP platform interconnects the wireless network and internet to provide mobile users a remote centralized storage and computation environment. A mobile user can store large volume of data and execute complex computations on WIRAP instead of on the mobile terminals. WIRAP supports different network interfaces (e.g. short message service (SMS), wireless markup language (WML) and hyper text markup language (HTML) and users may use terminals (with different network capabilities) to access WIRAP. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

11.
Willie W. Lu 《中国通信》2009,6(2):134-143
This paper relates to an advanced open mobile communication system and method of integrating the mobile communications, wireless access systems and wired communications into one common platform architecture for China's 4th generation mobile communications, supporting costeffective broadband voice, data and video services in wireless, mobile and wired environment with one single integrated mobile terminal device. The paper includes new architecture in the integrated mobile device and converged network access, and minimum modification in the existing mobile telecommunication infrastructures. This paper introduces the long-term evolution strategy for China's TDD system platform towards China's future 4G mobile communications.  相似文献   

12.
新一代应急综合通信系统的构建   总被引:1,自引:0,他引:1  
从应用和技术角度分析了应急综合通信系统的需求,提出了基于IP技术的综合网络通信平台——应急综合通信系统的构建方法,有效解决了目前城市应急联动系统亟待解决的3个问题:①传统的电话、VHF/UHF/HF无线电、新一代无线数字集群、VSAT卫星、移动电话网GSM/GPRS、计算机网络综合通信与互通互联;②移动(车载)指挥中心的综合通信;③指挥中心(包括固定和移动指挥中心)间的互联互通。  相似文献   

13.
无线异构网络的关键安全技术   总被引:1,自引:0,他引:1  
异构网络的融合及协同工作在下一代公众移动网络中将是一个很普遍的问题,无线异构网络融合技术作为改善公众移动网络的覆盖和容量以及提供无处不在的通信能力、接入Internet的能力和无处不在的移动计算能力的有效手段,已引起广泛的关注,有着良好的应用前景。构建无线异构网络的安全防护体系,研究新型的安全模型、关键安全技术和方法,是无线异构网络发展过程中所必须关注的重要问题。无线异构网络中的关键安全技术包括安全路由协议、接入认证技术、入侵检测技术、节点间协作通信等。  相似文献   

14.
Chen  Yih-Farn  Huang  Huale  Jana  Rittwik  Jim  Trevor  Hiltunen  Matti  John  Sam  Jora  Serban  Muthumanickam  Radhakrishnan  Wei  Bin 《Wireless Networks》2003,9(4):283-297
iMobile is an enterprise mobile service platform that allows resource-limited mobile devices to communicate with each other and to securely access corporate contents and services. The original iMobile architecture consists of devlets that provide protocol interfaces to different mobile devices and infolets that access and transcode information based on device profiles. iMobile Enterprise Edition (iMobile EE) is a redesign of the original iMobile architecture to address the security, scalability, and availability requirements of a large enterprise such as AT&T. iMobile EE incorporates gateways that interact with corporate authentication services, replicated iMobile servers with backend connections to corporate services, a reliable message queue that connects iMobile gateways and servers, and a comprehensive service profile database that governs operations of the mobile service platform. The iMobile EE architecture was also extended to provide personalized multimedia services, allowing mobile users to remotely control, record, and request video contents. iMobile EE aims to provide a scalable, secure, and modular software platform that makes enterprise services easily accessible to a growing list of mobile devices roaming among various wireless networks.  相似文献   

15.
本文从大都市移动电话网的现状出发,分析了移动电话发展的趋势,针对大都市移动电话的发展特点,对移动网的网结构和组网方案,基站和无线接入网的建设等方面进行了探讨。  相似文献   

16.
With an increasingly mobile society and the worldwide deployment of mobile and wireless networks, the wireless infrastructure can support many current and emerging healthcare applications. This could fulfill the vision of “Pervasive Healthcare” or healthcare to anyone, anytime, and anywhere by removing locational, time and other restraints while increasing both the coverage and the quality. In this paper, we present applications and requirements of pervasive healthcare, wireless networking solutions and several important research problems. The pervasive healthcare applications include pervasive health monitoring, intelligent emergency management system, pervasive healthcare data access, and ubiquitous mobile telemedicine. One major application in pervasive healthcare, termed comprehensive health monitoring is presented in significant details using wireless networking solutions of wireless LANs, ad hoc wireless networks, and, cellular/GSM/3G infrastructure-oriented networks. Many interesting challenges of comprehensive wireless health monitoring, including context-awareness, reliability, and, autonomous and adaptable operation are also presented along with several high-level solutions. Several interesting research problems have been identified and presented for future research.  相似文献   

17.
基于GSM网络的无线显示系统设计   总被引:1,自引:0,他引:1  
为了能够利用现有的移动通信网控制远端的电子显示屏,提出基于GSM网络的无线控制显示屏的解决方案,该系统由单片机及TC35无线接收器构成。控制者通过手机发送短消息,短消息经GSM网络传送到接收端,最终显示在显示屏上。结果表明,该系统结构简单,易于操作。  相似文献   

18.
Challenges in the migration to 4G mobile systems   总被引:9,自引:0,他引:9  
With the rapid development of wireless communication networks, it is expected that fourth-generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies including GSM, wireless LAN, and Bluetooth. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems supports comprehensive and personalized services, providing stable system performance and quality service. However, migrating current systems to 4G presents enormous challenges. In this article, these challenges are discussed under the headings of mobile station system, and service aspects. Proposed solutions to the research problems in each aspect are also examined.  相似文献   

19.
A performance evaluation approach for GSM-based information services   总被引:1,自引:0,他引:1  
The ever increasing diffusion of mobile communications will lead to massive mobile access to the Internet. The paper focuses on the wireless application protocol (WAP) for providing mobile information services, as envisaged by the personalized access to local information and services for tourists (PALIO) project within the fifth research framework of the European Commission. In particular, we consider a global system for mobile communications (GSM) network where WAP traffic is transported by the short message service (SMS) on specific GSM signaling channels. We develop suitable traffic models for both the WAP downlink traffic and the signaling traffic. An analytical approach is described that allows evaluation of the mean transmission delay of a WAP page. Finally, a downlink traffic scheduling policy is proposed in order to reduce the delay variance so that users experience a more regular traffic behavior (service usability requirement). The theoretical derivations for the GSM-SMS scenario are general and can also be tailored for other mobile communication systems. The study allows dimensioning of both the service and the downlink signaling traffic capacity in order to fulfill quality-of-service requirements for users.  相似文献   

20.
Software testing for wireless mobile computing   总被引:1,自引:0,他引:1  
4G wireless networks make it increasingly difficult to develop and test application software for mobile terminals in comparison with 3G or earlier generations. These 4G networks incorporate wireless LAN technologies, and mobile terminals can access the services provided by LANs as well as global network services. Therefore, software running on mobile terminals may depend on not only its application logic but also on services within the LANs to which the terminals are connected. To construct correct software to run in mobile terminals for 4G wireless networks and wireless LANs, it must be tested in all the networks to which the terminal could be moved and be connected. This article presents a new approach, called flying emulator, to testing software designed to run on mobile terminals. Like existing approaches, the approach provides software-based emulators of its mobile terminals for software designed to run the terminals. It is unique because it constructs emulators as mobile agents that can travel between computers. These emulators can carry the target software to the networks to which the terminals are connected and allow it to access services provided by the networks in the same way as if it was moved with and executed on the terminals connected to the networks. This article describes the idea of the approach, its implementation, and our experience with a typical application.  相似文献   

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