万兆以太网物理层编码子层转换芯片研究

研制了符合IEEE802.3ae万兆以太网10GBASE-R标准物理层编码子层转换芯片,该转换芯片采用单片FPGA进行10GBASE-R标准中万兆以太网16比特接口(XSBI)与10Gb介质无关接口(XGMII)的相互转换,实现了物理层编码子层(PCS)的全部功能,并在万兆以太网物理层传输实验系统中进行了验证。     

万兆以太网物理层转换芯片研究

研究符合IEEE802.3ae标准的万兆以太网10GBASE-X和10GBASE-R物理层技术,采用商用FPGA实现了万兆以太网16比特接口(XSBI)和10GE连接单元接口(XAUI)的相互转换。该转换芯片实现了物理编码子层(PCS)、物理介质连接子层(PMA)的全部功能。采用商用评估板进行测试,在接收端恢复出万兆以太网帧结构数据,逻辑功能正确。     

基于FPGA的万兆以太网接口的设计与实现

介绍了IEEE802.3ae标准中万兆以太网物理层及媒质接入控制子层的相关协议.以10GBASE-R应用物理环境为例,阐述了万兆以太网接口各个单元模块的功能和设计实现方法.FPGA仿真结果表明,该万兆以太网接口可以实现以太网之间的万兆接入,对以太网的应用空间和性能提升有着重大的意义.     

万兆以太网技术的研究与实现

为了提高通信系统的数据吞吐量,增加系统集成度,在IEEE 802.3ae标准的基础上,对万兆以太网技术进行了研究并实现。万兆以太网技术是基于FPGA实现的,FPGA完成的主要工作包括:完成与上层软件的指令和数据交互、数据的组帧/解帧、与物理层的接口管理等。物理层发送端主要完成数据对齐、变速并加扰、并串转换等工作,将串行数据发送给光电转换模块,接收端正好相反。经过万兆以太网标准仪器测试,传输速率达到了10 Gb/s,大大提高了系统间数据传输的速度和效率,简化了系统结构。     

基于FPGA的万兆协议转换系统设计与实现

万兆通信技术已成为卫星通信领域又一研究热点,为星上设备提供高速可靠的万兆数据源尤为重要。系统采用Xilinx公司新近推出的K7系列现场可编程门阵列(FPGA),利用其吉比特收发(GTX)接口模块和万兆媒体访问控制(MAC)软核实现了万兆协议转换功能。通过状态机设计方法实现了以太网协议帧和专用链路协议帧之间的相互转换。通过测试结果可知,系统达到了每通道10 Gb/s的转换带宽,总带宽达到40 Gb/s,能够满足星上设备的测试需要。     

10Gbit/s并行光收发模块在万兆以太网的应用

介绍了万兆以太网技术(10 gigabit ethernet technology).万兆以太网使用以太网结构实现10Gbit/s点对点传输,距离可达到40km,使以太网的应用从局域网扩展到城域网和广域网.重点介绍了万兆以太网的功能结构、分层结构、物理传输介质和甚短距离(very short reach)网络传输的并行光传输系统在万兆以太网方面的应用.     

10Gbit/s并行光收发模块在万兆以太网的应用

介绍了万兆以太网技术(10 gigabit ethernet technology).万兆以太网使用以太网结构实现10Gbit/s点对点传输,距离可达到40km,使以太网的应用从局域网扩展到城域网和广域网.重点介绍了万兆以太网的功能结构、分层结构、物理传输介质和甚短距离(very short reach)网络传输的并行光传输系统在万兆以太网方面的应用.     

BCM8481：10GBASE-T收发器

采用65nm工艺制造的万兆以太网（10GbE）物理层（PHY）收发器,支持在长达100米的6A类非屏蔽双绞线（UTP）或7类铜缆线上运行IEEE802．3 10GBASE-T。Broodcom 10GBASE-TPHY是唯一能够支持在4种不同的以太网速率（10／100／1000Mbps和Gb／s）之间进行白适配的器件。因此,它能够很好地和目前已经安装使用的各种以太网兼容。     

网捷网络：主导快速增长的第3层万兆以太网市场

网捷网络是第一家提供万兆以太网产品的网络公司，其万兆以太网产品于2001年10月就开始交付使用。目前，网捷网络公司正在向客户提供从网络边缘到核心的具有业界最高扩展性、产品线最丰富的万兆以太网产品。近期，网捷网络发布了多款业界领先的万兆以太网产品，其中包括获奖的高性能Bigiron MG8万兆以太网模块化交换机的主要可扩展性和性能的增强版本以及Fastlron Edse和Edgelron产品线中的全新万兆以太网小型汇聚、工作组和堆叠式交换机。网捷网络还推出了几种全新的万兆以太网XENPAK光收发器，其中包括业界第一款模块化万兆以太网广域网物理层(WAN PHY)光收发器。     

基于10G以太网物理层的RPR融合技术研究

参照吉比特/10吉比特以太网的融合子层,探讨了弹性分组环MAC层协议实体在10G以太网的物理层上需要的接口处理,提出了利用10吉比特介质独立接口(XGMII)的融合方案,这对于指导弹性分组环MAC层、融合子层(ReconciliationSublayer,RS)的设计与实现具有重要意义。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

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.