基于FPGA的视频帧同步机的设计

描述了一种可以支持实时数据流处理的帧同步方法.该方法用SDRAM做帧存储器,存放一帧视频数据,用FPGA实现数字视频解串、串化、帧同步逻辑控制以及SDRAM控制器等功能,用同步器连接异步模块的方法解决异步时钟域信号传输问题.该设计方法可完成标清数字视频的帧同步功能.     

视音频延时器用大容量FIFO的设计

介绍视音频延时器用大容量FIFO的设计,大容量FIFO的设计采用了SDRAM代替双口RAM,并采用FPGA设计双口SDRAM控制器.该FIFO也可用作高速数据采集系统的数据缓冲.     

嵌入式实时图像处理系统中SDRAM控制器的实现

介绍一种用于嵌入式实时图像处理系统的SDRAM控制器的实现方案.根据实时系统对数据传输速率及连续性的要求,将SDRAM配置为全页突发操作模式,并采用异步FIFO作为FPGA与SDRAM间的数据缓冲器.为配合SDRAM的全页操作模式,并充分利用其高速读写性能,将FIFO设计为基于乒乓操作的流水线结构,实现了数据的无缝缓存.将该方案用于实时红外热成像系统,经实验结果表明,该SDRAM控制器执行效率高,占用资源少,可移植性强.     

基于FPGA的高速大容量异步FIFO的实现

为了实现测试光纤陀螺仪的大量的数据采集,提出了一种基于FPGA的高速大容量异步FIFO控制器的实现方法,分析了所用SDRAM的特点和工作流程,设计出了实现这种控制器的方法。最后给出了SDRAM控制器的写数据仿真结果图。此设计基本满足了测试光纤陀螺仪数据采集和数据存储的要求。设计中采用SDRAM作为FIFO缓冲器,利用FPGA实现对SDRAM的控制。这种方法通用性好且成本低,可以应用在任何一种有大容量数据缓冲要求的系统中。     

基于FPGA的双端口视频缓冲器设计

介绍一种基于FPGA和SDRAM的双端口的视频缓冲器设计方法。使用小容量的同步FIFO和异步FIFO串联构成用户接口,采用分块方式读写单块存储器SDRAM,采用混合算法合理仲裁读、写和刷新请求,实现单路视频数据的实时采集和输出。本系统设计简单,调试方便。只需适当地改变数据块的长度和FIFO的容量就可以应用于其他的视频处理系统。仿真测试结果表明:SDRAM时钟频率工作在71MHz下可以确保视频流的流畅性。而且通过改变FIFO的相关参数,还可以继续提高SDRAM的实际带宽。本设计还具有一定的灵活性。     

一类基于AMBA总线的SDRAM控制器设计

提出一类SDRAM控制器的设计方法,针对SDR SDRAM的突发特性,采用数据预读取机制提高SDRAM的读取效率,同时又加入了写指令FIFO消除读缓存带来的负面影响.并且以该控制器在AHB总线的集成为例,实现了控制器在SoC中的应用.功能仿真和FPGA验证均表明本设计能够准确高效地实现对SDR SDRAM的访问控制.     

基于FPGA的高速海量FIFO的设计

为了解决视频信号的大量存储及视频延时问题,研究了一种以DDR2 SDRAM为存储体的高速海量FIFO设计方法.该方法通过采用FPGA对DDR2 SDRAM进行控制,以状态机来描述其各种时序操作,来完成DDR2 SDRAM的命令和数据的接口,从而实现数据的正确有序的存取.另外,流水式处理的方式,也保证了输入输出数据的连续性.经过最终硬件的成型和下栽调试,验证了该方法的可行性和可靠性.该系统已经成功应用于视频的延时处理.     

基于FPGA的通用PCM接收解码电路的设计

为了准确接收提取某遥测系统的PCM数据,设计了基于FPGA的通用PCM接收解码电路,该电路通过基于锁相环的位同步器实现不同码率的PCM数据流接收,通过三态搜索理论的帧同步器可判别不同帧结构数据,码型转换模块识别并转换NRZ-L/M/S、BiФ-L/M/S 6种码型,最后电路将解调出的数据通过USB接口传送至计算机进行存储、显示和处理。该电路可识别码型不同、码速率不同以及帧同步码组不同的PCM数据流,兼有单端和差分输入接口,在遥测领域具有很强的通用性。     

基于Kintex-7 FPGA的DDR3 SDRAM接口应用研究

针对FPGA中使用DDR3进行大容量数据的缓存应用背景,采用模块化设计方法,提出基于Xilinx Kintex-7 FPGA的DDR3 SDRAM FIFO接口设计方案。在分析DDR3用户接口特点和用户接口时序的基础上,对不同读/写模式进行效率测试。借鉴标准FIFO的设计思想,结合DDR3 SDRAM控制器的特点,设计遍历状态机对该FIFO接口进行读/写测试。最后,原型机平台验证了该接口不仅具有标准FIFO简单易用的功能,而且具有存储空间大等优势。     

基于FPGA的SDRAM读写双口控制器设计

在研究了SDRAM工作特性的基础上,提出了利用FPGA将单片SDRAM作为乒乓RAM的双口接口设计。采用ALTERA公司的EP1C6Q240C8和HYNIX的HY57V161610DTC-8，将FPGA作为主控制器，并在其中配置两块删分别作为SDRAM的输入、输出缓冲区。前者接收外设慢速数据流，经处理后写入到SDRAM，后者读取SDRAM中数据,为外围高速设备提供高速数据流。高速数据流按自定义数据包间续发送，在此问隔中执行慢速数据流写入SDRAM和自动刷新SDRAM的操作。     

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.     

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.