基于模拟IC测试的任意波形发生器设计与实现

面向模拟IC自动测试仪设计并实现了一种由FPGA控制的任意波形发生器.设计采用闭环控制的方法,保证任意波形发生器输出信号的高精度.任意波形发生器波形数据存储深度最大可达128 MB,采样精度为16位,最高采样率可达到160 MHz,输出信号频率为1 Hz～1 MHz,峰峰值范围为20 mV～20 V,幅度偏置范围为＋2.5 V,精度可达到±0.1 dB.实际测试表明该设计满足模拟IC测试仪的项目要求.     

DDS任意波形发生器研究

工程实践中往往会应用到多种信号形式的信号源。为了实现信号源中信号的多样性,采用直接数字额率合成技术设计了一种任意波形发生器。波形存储器中存储的波形数据是任意波形发生器的关键,详细说明了使用Matlab生成波形存储器中波形数据的方法。采用上述方法得到了一种工程实践中常用的扫频信号仿真波形图。实验表明,所设计的任意波形发生器实现简单,可编程,适合广泛应用于工程实践中。     

宽带高纯频谱任意波形发生器的设计

信号波形的复杂化和多样化设计是当今雷达与电子战系统工程师所要面对的重要问题.文中介绍了一种基于高速数模电路的任意波形发生器设计思路及其工程实现模型,并就其相位噪声、杂散电平等性能加以分析.最后介绍了任意波形发生器的几个典型应用.     

4GHz带宽任意波形发生器设计

针对高采样率大带宽复杂波形信号的测试需求,设计实现了一种宽带任意波形发生器.采用国产高速DAC芯片、高性能FPGA和宽带可控增益放大器的设计方法,国产DAC集成CML数据接口,保证了传输带宽.测试结果表明:该系统支持10 GSPS采样率、4 GHz带宽的任意波形信号输出,具有良好的性能.     

基于QDRII的一种PXI任意波形发生器数字部分的设计

随着测试技术的发展,对信号的要求越来越高,高采样率任意波形发生器被广泛应用于各种测试系统中.文章重点介绍了在PXI 3U板卡上实现采样率高达200MS/S的任意波形发生器模块的设计.设计中采用QDRII代替了SRAM,解决了由于存储器带宽过小而阻碍任意波形采样率提高的问题.     

最新高端函数／任意波形发生器集成丰富功能

普源精电(RIGOL)目前推出一款高端信号源产品--DG5000系列函数/任意波形发生器.DG5000系列函数/任意波形发生器集成了矢量信号调制、跳频信号输出等丰富功能,是一款多功能的高端信号源.     

泰克AWG70000任意波形发生器满足高标准信号发生需要

由于所有电子和射频细分市场领域的数据率与信号复杂性都不断增加,因此工程师和研究人员需要更先进的信号发生器对设计进行充分的压力测试或者开展前沿研究。泰克公司日前推出采样率高达50GS/s的下一代任意波形发生器新AWG70000。通过提供高采样率、长波形内存和深动态范围组合,新AWG70000系列任意波形发生器可满足宽带电子、高速串行通信、光网络及高级研究应用领域的广     

基于QDRⅡ的一种PXI任意波形发生器数字部分的设计

随着测试技术的发展,对信号的要求越来越高,高采样率任意波形发生器被广泛应用于各种测试系统中。文章重点介绍了在PXI 3U板卡上实现采样率高达200MS／S的任意波形发生器模块的设计。设计中采用QDRⅡ代替了SRAM。解决了由于存储器带宽过小而阻碍任意波形采样率提高的问题。     

一种新型虚拟任意波形发生器的设计

通过分析传统任意波形发生器（AWG）的局限性,提出了一种基于通用串行总线（USB）和直接数字频率合成（DDS）技术的新型虚拟AWG的设计方法,并详细讨论了虚拟AWG的软件设计及硬件实现。该波形发生器操作灵活,可以产生任意波形的周期性信号,能灵活控制波形的幅值、频率和相位,并且在很宽的频率范围内快速切换频率,在自动测试、雷达等方面有着广泛的应用价值。     

任意波发生器的研究与设计

在任意波形发生器设计中,DDS技术具有成本低、功耗小、分辨率高和切换时间快等优点,但波形形状任意可编辑性较差;软件无线电技术可产生任意复杂波形,但切换时间慢。采用DDS和软件无线电相结合的技术,正弦波、三角波、方波等普通信号的产生用DDS实现;复杂无规则波形信号的产生用软件无线电实现;最后任意波形发生器通过波形存储器、相位累加器、取样时钟发生器、地址发生器等硬件平台设计和软件波形算法设计来共同完成。     

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.     

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.     

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.     

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.     

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.