基于IP城域网承载IPTV业务的研究与实现

通过分析IPTV业务的承载需求,指出通信运营商现有的IP城域网不能满足日益增长的IPTV业务需求,IP城域网需要升级改造。分别从IPTV系统架构、业务接入设计、组播部署、IPoE部署、业务隔离、QoS部署等方面对IP城域网的接入和承载能力进行优化和改造。改造后的应用实践表明：运营商可在现有网络中有效地开展IPTV业务,并保障业务有良好的承载效果。     

IP RAN配套接入光缆优化思路

针对LTE对承载网的需求以及IP RAN组网特点,提出了IP RAN接入光缆网优化的原则,并结合现有ODN网络资源,给出3种接入光缆优化模式,提升接入光缆的多业务承载能力,提高IP RAN网络安全性。     

多业务系统共用CE设置方案探讨

基于全网IP化进程不断加深、各业务系统CE数量不断增加的背景,本文通过对现有IP承载网承载业务的介绍,探讨了多业务系统共用CE的可行性,提出了多业务系统共用CE的设置方案。     

cdma2000分组数据安全研究

首先介绍了cdma2000系统的两种核心网接入业务——简单IP和移动IP业务的网络参考模型，然后重点分析了这两种接入业务的分组数据安全体系结构，最后对移动IP中的IPSec协议结构作了进一步探讨。     

技术动态

中兴通讯发布新一代ALL IP承载网解决方案本刊讯10月21日,中兴通讯在2008年中国国际信息通信展览会(PT/EXPO COMM CHINA2008)发布了新一代ALL IP承载网解决方案,旨在为运营商在全业务运营下的转型提供强大动力。中兴通讯的新一代ALL IP承载网解决方案可以实现多种传统和新兴业务、固网和移动业务的统一和融合,在业务控制层通过CE路由器对各类业务服务器进行统一的IP承载,在汇聚接入层通过CE/PTN技术实现移动、固     

TD—SCDMA RAN IP化应积极开展PTN承载规模试验

目前TD—SCDMA RAN的IP化可采用MSTP技术承载，并逐步过渡为采PTN技术承载。PTN在承载IP化无线接入网方面优势明显，比如：PTN具有基站E1／FE、全业务接入的业务承载能力；支持网络保护倒换；能提供面向连接、层次化QoS、OAM和图形化网管系统等特点，特别是在图形化网管这方面。     

从全IP网络特征看3G发展方向

全IP网络是从系统概念的层面上对以往3GPP系统进行改进和优化，包括与IP技术融合、支持各种接入系统以及在此基础上向用户提供高质量有保障的综合业务，确保在未来10年甚至更长的时间内具有竞争力。本文对全IP网络的基本特征进行分析，有助于把握3GPP系统发展的大方向。     

IP承载网CE的高可用系统方案研究

IP承载网是中国移动以IP技术构建的一张专网,用于承载对传输质量要求较高的业务(如软交换语音、视讯、重点客户VPN等),随着业务规模的不断扩大以及网络本身的不断发展,对网络本身的可靠性提出了更高的要求,尤其是对于IP承载网面向业务接入的CE路由器的高可用面临越来越大的挑战,现有IP承载网CE路由器拥有自身构造的电信级高可用之外,虽然已经实现成对CE互为主备容灾的方式承载业务,当出现单台CE路由器故障情况下业务一般能通过另一台CE绕转承载,从而实现业务不受影响。但是通过深入分析IP承载网的组网结构特点及风险,发现比如:当发生CE路由器的互联端口异常/设备单板故障/传输通道故障/传输尾纤故障等场景时,CE路由器仍然存在单节点失效甚至成对CE路由器同时退服的风险,另外,现有CE的带外应急手段缺失、备件管理无序等也同样制约了CE的高可用性。本文从IP承载网的组网架构、应急手段、备件储备等方面提出针对性的高可用网络的建设方案,显著提升了网络承载的高可用性。     

从全IP网络的基本特征看3G的发展方向

为了确保在未来10年甚至更长的时间内具有竞争力，全IP网络从系统概念的层面上对以往3GPP系统进行改进和优化，包括与IP技术融合，支持各种接入系统，以及在此基础上向用户提供高质量有保障的综合业务。本文对全IP网络的基本特征进行分析，有助于把握3GPP系统发展的大方向。     

基于CWDM的城域多业务复用接入系统研究

在分析了城域接入网业务需求和宽带无源光网络发展的基础上,提出了采用CWDM技术构建新型多业务复用接入系统的方案.设计系统采用双向CWDM传输技术提升了网络的容量和业务承载能力,并通过使用光放大器扩大了网络覆盖范围.系统采用分别发大IP信号和视频信号的结构解决了数字信号与模拟信号共纤传输的增益不均衡问题.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks