智能ODN在宽带接入网中的应用

针对已有ODN(光分配节点)的现状与不足,提出智能ODN在宽带接入网中的解决方案,建立智能ODN设备和网络模型,利用智能OTDR(光时域反射仪)和智能管理,给出系统框图,并将传统ODN与智能ODN进行比较。实践证明,智能ODN不仅能解决海量光纤的管理和提升运营维护效率,还能降低工期和成本,实现光纤故障准确定位。     

智能光配线网络技术的研究

智能 ODN(光配线网络)技术是将电子标签技术应用到传统 ODN中,利用电子标签标识 ODF(光纤配线架)设备端口资源。文章提出一种基于电子标签的新型光纤指环技术,用其对光纤唯一性进行标识,具有读取方便、稳定高效等优点。系统实现了光纤信息数据的自动存储与上传、监控光纤正确接入 MUMM(熔配单元盘)和光纤资源信息校准等功能,从而解决了智能 ODN技术难题。     

基于OTDR的PON光纤故障定位方法

针对目前PON面临的光纤故障问题,对基于OTDR的光纤定位技术进行了研究.结合OTDR的定位原理,利用光纤故障会导致OTDR测试曲线发生变化的特点,提出PON的光纤故障定位方法,并利用该方法搭建PON故障定位集中测量系统.实验平台验证了PON光纤故障定位方法的效果及局限性.     

智能ODN解决方案及应用探讨

智能光分配网络(ODN)技术因具有可管可控、稳定高效等优势,已成为近期光纤接入(FTTx)网络建设与改造的研究重点。首先,通过简单介绍业界三种典型的智能ODN解决方案,然后分析各自的差异性和优缺点,并提出了一种基于电子标签和二维码的智能ODN解决方案。最后,对智能ODN系统的发展进行了展望,认为制定智能ODN规范标准以及提高产品兼容性对实现ODN规模化发展及差异化运营具有重要的意义。     

智能ODN技术在FTTx网络中的应用分析北大核心

面对海量光纤管理维护难题,智能光分配网(Optical Distribution Network,ODN)开启全新管理模式,即通过增加电子标签赋予光纤网络智能特性。针对华为、中兴和烽火3家主流设备商相继推出的智能ODN技术在解决方案、功能特性、部署方案、研究现状等方面进行对比分析。商用测试部署证明,各家方案均能够实现光纤智能管理、故障定位及施工指导等功能。     

基于双正交编码的波长可调谐OTDR研究

传统的基于光时域反射计(OTDR)的光纤链路监测技术,在用于WDM-PON系统的光纤链路的在线监测时面临如波长可调谐,功率受限下的大动态范围等问题.文章针对这一应用需求,对基于双正交编码的波长可调谐OTDR技术进行了理论和实验研究.通过采用64bit的双正交编解码(Biorthogonal Codes)技术,经512次的累加平均,即可将OTDR的信噪比(SNR)提高约14.7dB,可以实现满足WDM-PON光纤链路在线监测需求的波长可调谐OTDR.     

OTDR应用于PON ODN测试与诊断分析

光宽带的规模建设带来了接入网光纤光缆的海量建设,大建设应用后重点在于光网运营维护管理,因而高效的光网检测手段及其相关的灵活应用方式非常重要.在分析ODN组网基础上,研究OTDR应用于ODN的测试能力,重点分析了OTDR测试中ODN关键事件的特征,同时根据ODN建设模式和OTDR检测缺点,针对性提出了相关应用方案.     

ODN“智能化”的考虑

智能ODN将电子标签技术应用到传统ODN中,利用电子标签对光纤进行惟一标识,自动存储、导入和导出光配线设备端口资源及光纤连接关系数据,从而实现光纤信息自动存储、光纤连接关系信息自动识别、光纤资源信息校准、可视化施工指导等功能。本文对智能ODN的系统构成、智能ODN关键技术的现有差异以及发展前景进行了探讨。     

ODN“智能化”的考虑

智能ODN将电子标签技术应用到传统ODN中,利用电子标签对光纤进行惟一标识,自动存储、导入和导出光配线设备端口资源及光纤连接关系数据,从而实现光纤信息自动存储、光纤连接关系信息自动识别、光纤资源信息校准、可视化施工指导等功能。本文对智能ODN的系统构成、智能ODN关键技术的现有差异以及发展前景进行了探讨。     

ODN网络在线运维的解决方案

介绍了一种基于华为专利技术的PON网络区分分支光纤的方法,该方法可以单独显示分光器后各个分支光纤的OTDR测试曲线,便于准确识别各个分支的光纤衰减事件和反射事件,并探讨这一方法对运营商在ODN网络的工程验收、业务发放、资源管理和故障分责等方面所能够提供的帮助。     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

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.     

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.     

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.     

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.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.