基于EPON+EoC技术模式下的广电双向网的运营和维护

广电双向网络经过几年的发展,已达到了一定的规模.随着双向用户大量发展,确保EPON+EoC技术模式下双向网络的正常运营和维护显得尤为重要.通过对EoC的原理、故障和扩容等问题的阐述,加强对EoC模式下的双向网络维护技术手段和力量.     

三网融合下有线双向网络技术及接入方案比较

＂三网融合＂指的是网络、技术、业务以及相应的模式全面融合,它并不意味着电信和广电从此合并,而是从网络结构、传输技术以及业务模式方面相互融合,取长补短,杜绝竞争式的重复性网络投入。主要从网络技术的角度,分析有线网络在双向化改造过程中的关键技术及其特点,以及几种典型的双向改造的模式,浅谈下一代双向网络方案。     

当前广电网络双向改造主要技术模式

广电网络双向改造的目的是将现有的单向传输、下行广播式的有线电视网络改造成双向传输、上下行互动式的网络。本文通过对当下广电网络双向化建设的几种主要技术模式的基本架构、网络优点的介绍分析,阐述选择正确的双向网络改造方案的重要和必要性。     

广电双向网络建设规划与运营实施

本文主要介绍了三网融合背景下广电双向网络建设与规划的思路,全面阐述了双向网络建设的具体模式与应用特点,针对双向网建设与规划中存在的问题,提出了适当的解决方案,对广电网络公司双向网络建设具有参考和借鉴意义。     

FTTH模式在广电双向网络改造中的可行性探讨与实践

目前各宽带网络运营商在宽带市场中的竞争日趋激烈,所使用的技术模式也更加多样化,随着三网融合的推进和7部委关于加快推进光纤宽带网络建设意见的出台,FTTH技术模式已经成为主流。根据宽带市场的竞争环境和广电的现状来探讨分析FTTH模式在双向网络改造中的可行性,并以网络改造的实践论证FTTH模式是适合广电双向网络改造的最佳方案。     

有线电视双向网改造模式选定分析

在三网融合的背景下,剖析了东海县有线电视网络现状及双向网改的必要性,并从3个方面分析了双向网络改造各种模式之优缺点,据此确定了东海有线电视网络双向改造的方案。     

广电网络双向改造实施技术探讨

广电网络双向改造技术实施的目的与方向就是将单向传输、下行广播式有线电视网络,通过技术改造实现成双向传输、上下行互动传输的网络形式.本文首先分析了广电网络双向改造相关信息;然后,对CMTS系统进行了介绍,并探讨了网络双向化技术实施的四种方案:EPON+EOC方案、EPON+LAN方案、FTTH模式、RFOG技术;最后,通过双向网络改造技术方案的分析,探讨了现阶段主要技术模式的基本架构与网络有点等.     

双向HFC＋CM网络模式是西部地区县级广电运营商开展双向增值业务的最佳选择

本文以西部地区县级广电网络的现状为出发点,指出以双向HFC＋CM的网络模式是支持西部地区县级广电网络运营商开展双向增值业务、实现可持续发展的主要网络技术模式。     

利用EPON＋EoC进行HFC双向网络改造技术探讨

目前各地正在进行数字化整体平移,数字化使整个有线电视的业务、运营模式发生了革命性的变化。原有HFC网络需改造实现双向,网络双向改造需根据各地实际情况和技术的发展选择性价比最高的方案。本文就目前实现网络双向化改造的无源光网络EPON技术和各种最后100米同轴接入技术进行探讨。     

广播电视有线网络双向化技术研究

广播电视有线网络进入了千家万户,为了更好地满足客户的新型需求,更大范围地占据市场,广播电视有线网络进行了双向试点建设和NGB网络同步示范建设,这种双向化技术,更好地实现了广播电视的双向化信息交流。在三网融合的背景下,广播电视有线网络将彻底转变原有的单向电视广播传输运营模式,改造升级为一种新型的、可以承载电信和电视业务双向宽带入网的系统。     

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