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1.
随着移动通信的发展,各种无线电话网与有线电话网通过有线/无线转接器实现有线用户与无线用户间的通信越来越广泛。本文从硬件电路处理及软件识别两个方面介绍了有线/无线转接器中有线呼无线时对DID信号的处理方法。  相似文献   

2.
王云 《中国有线电视》2007,(16):1488-1490
介绍有线数字电视双向网的组成,论述建设城市有线数字电视双向网络的5个基本组成部分以及各部分在网络建设中的技术要求,系统介绍HFC光纤传输网、电缆分配网的组成,分析FTTC与FTTB之间的关系。  相似文献   

3.
详细介绍了有线数字电视双向网设计的总体规划和设计要求,并具体分析了有线数字电视双向网的调试过程,主要包括正向调试和反向调试两部分,对其他城市的双向网调试具有一定的借鉴意义。  相似文献   

4.
本文主要介绍了有线无线卫星融合网开展的业务规划分类,详细介绍了各种业务的具体形式,并结合这些业务的规划,介绍了融合网络中的网络终端和用户终端,业务和终端规划将指导有线无线卫星融合网的建设和落实.  相似文献   

5.
介绍了马鞍山有线宽带数据网的设计与组网方案。  相似文献   

6.
《中国有线电视》2011,(6):721-721
5月25日,上海市有线网络运营商东方有线网络有限公司隆重召开“网·融新生活:NGB网络及三网融合业务新闻发布会”,向社会公众详细介绍了上海下一代广播电视网(NGB)建设进展,  相似文献   

7.
主要阐述了数字电视的基本概念及其在有线电视网中的传输方式,重点介绍有线数字平台的基本结构,以及有线电视网开展数字电视传输的各种类型综合业务分析。  相似文献   

8.
随着三网融合时代的到来,有线电视网络的业务将发生革命性的变化,视频、数据、语音业务将全面展开。有线电视网络在现网基础上进行快速、低成本的改造,形成下一代广播电视网络是当前面临的重大课题。为推进三网融合业务发展,青岛有线结合自身网络实际情况,提出了“同纤共缆“的网络改造扩容方案,形成了一种有线网络双向改造扩容的新思路,本文将从多个角度介绍青岛有线这一实施方案的具体情况。  相似文献   

9.
目前有线电视网正向星-树形结构的光纤同轴混合网发展,以此为基础建设宽带用户接入网成为人们关注的一个课题,本文介绍了目前有线电视网的发展状况,并对它在向宽带接入网过渡中的关键技术和发展策略进行了讨论。  相似文献   

10.
本文从如何在SDH网搭建有线数字电视传输平台的角度,对SDH网络现状、网络扩容和在SDH网搭建数字平台技术作了分析。主要介绍金华有线数字电视平台,以及基于SDH网络对DS3、IP数字电视信号以及VOD点播业务的传输。  相似文献   

11.
柴晓蕾  李辉  冯平 《电子测试》2009,(7):34-36,61
随着各运营单位的重组和3G牌照的发放,各通信网络的融合与完善对IMS网络发展提出了更高的要求。模拟IMS网络,测试IMS网络,完善IMS网络,使得IMS实验网的搭建变得至关重要。本文介绍了IMS网络的基本结构和功能,采用相关研究工具,组建IMS实验网,部署实现包括P-CSCF、I-CSCF、S-CSCF、HSS和AS等功能实体,实现IMS网络的基本的通信,设置AS提供增值服务。经过测试,验证了系统设计的有效性,为用户带来全新体验。  相似文献   

12.
介绍了澳大利亚插头产品的法规要求及插头的型式、尺寸、参数和测试要点,分析了插头的电流额定值和配线之间的关系,强调了插销绝缘套的要求。对重要的试验项目,如弯曲试验、插销绝缘套的耐磨试验、温升试验、高温压力试验进行了说明。  相似文献   

13.
Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost, complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed schemes from the security and operation point of view summarizes their relative performance. Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in 1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over 15 papers in the above areas. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.  相似文献   

14.
随着企业规模逐渐扩大,远程用户、分支机构、合作伙伴也在不断增多,关键业务的需求增加,出现了一种通过公共网络(如Internet)来建立自己的专用网络的技术,这种技术就是虚拟专用网(简称VPN)。本文首先介绍了VPN的概念,对VPN的实现技术进行了分类和适用性分析,然后分析了各种类型的企业在信息安全方面的需求和限制,根据不同企业的特点提出了不同的VPN解决方案,最后,对VPN在集成电路企业中的应用做了简单的拓朴展示。  相似文献   

15.
RFID技术作为一项重要的非接触式识别枝术,近来发展迅猛。本文对RFID天线相关的技术进行了专利战略分析,主要包括:RFID天线相关整体行业分析、RFID标签天线和制造工艺等三个方面,分析了如下主要指标:申请年度发展趋势、主要申请人地区分布、IPC分布、DWPI分布、主要申请人分布、核心专利排名、专利地图。根据分析结果,本文给出了分析结论,对相关企业在专利利用、保护和管理方面给出了建议与对策。  相似文献   

16.
RFID相关技术专利分析(二)   总被引:1,自引:0,他引:1  
RFID技术作为一项重要的非接触式识别技术,近来发展迅猛。本文对RFID天线相关的技术进行了专利战略分析,主要包括:RFID天线相关整体行业分析、RFID标签天线和制造工艺等三个方面,分析了如下主要指标:申请年度发展趋势、主要申请人地区分布、IPC分布、DWPI分布、主要申请人分布、核心专利排名、专利地图。根据分析结果,本文给出了分析结论,对相关企业在专利利用、保护和管理方面给出了建议与对策。  相似文献   

17.
基于统计判决的关联决策是当前多雷达数据关联的一个有效途径.然而,在采用该方法对高超声速目标数据关联的问题进行研究时,却会出现随着雷达测量精度的提高,不同雷达数据关联的正确关联概率反而下降这一现象.针对这一情况,首先,利用线性调频(linear frequency modulated,LFM)雷达合理构建了基于统计判决的高超声速目标数据关联模型;接着,在现有的统计判决机制下,进一步分析了目标高超声速运动对多LFM雷达数据关联的影响,并得出了其关联判决函数(服从非中心卡方分布)与现有的关联判决门限(服从卡方分布)相矛盾的结论;最后,结合统计学的原理,通过对目标非中心统计参量的有效求解,合理解释了上述奇怪现象的出现.仿真结果表明,在目标高超声速运动的条件下,上述奇怪现象的出现是合理的.  相似文献   

18.
徐春霞 《电子工程师》2004,30(5):65-67,73
在讨论了接入控制器(AC)网络管理系统安全重要性的基础上,分析了SNMP协议的应用,包括对其3个版本SNMPv1、SNMPv2及SNMPv3的优缺点的对比,并解释了该设备网络管理系统采用SNMPv3版本的原因.详细介绍了AC所实现的管理信息库的内容,包括RFC1213协议、IEEE 802.1x协议、RMON协议、Web DHCP、EAP_OTP、EAP_MD5、EAP_TLS、EAP_SIM等多种认证协议以及网络管理系统的五大功能.最后阐述了AC安全网络管理系统结构的设计与实现.  相似文献   

19.
雷达探鸟技术发展与应用综述   总被引:3,自引:0,他引:3  
探鸟雷达已成为机场鸟击防范、风力发电场鸟击风险评估、鸟类自然保护区鸟情观测与科学研究的重要工具。文中首先论述了探鸟雷达的主要组成部分。然后,分析了地面杂波、空域杂波和其他无关目标对探鸟雷达探测效果的影响,进而介绍了传统的杂波抑制方法和相参雷达杂波抑制技术,以及先进的探鸟雷达采用的目标检测、目标跟踪、目标显示、数据记录和雷达组网等数据处理技术。接着,给出了当前的探鸟雷达能够获取的目标轨迹、回波大小、回波强度、信号波动、飞行速度、飞行高度等反映飞鸟目标特性的主要指标。最后,描述了国内外四种典型雷达探鸟系统,并针对雷达探鸟技术的未来发展提出了一些思考及可行性建议。  相似文献   

20.
Thanks to their structure, the SOI technologies present several intrinsic advantages for analog and RF applications. Indeed, as it is well established now, these technologies allow the reduction of the power consumption at a given operating frequency. Moreover, the high-insulating properties of SOI substrates, in particular when high resistivity substrate is used, make that these technologies are perfect candidates for mixed-signal applications. In the present paper, we will discuss the performances of the SOI technologies in radio-frequency range. First of all, the high-frequency behavior of SOI substrates, thanks to the characterization of transmission lines, will be shown. The impact of the SOI substrate resistivity on the performances of passive components will also be analyzed. Then, an overview of RF performances of SOI MOSFETs for two different architectures, fully- and partially-depleted, will be achieved and compared to the bulk ones. Finally, the influence of some specific parasitic effects, such as the kink effect, the self-heating effect and the kink-related excess noise, on the RF performances of SOI devices will be studied, thanks to a specific high-frequency characterization.  相似文献   

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