采用高速FIFO和双CPU的光纤陀螺捷联系统

在光纤陀螺构成的捷联惯导数据采集系统中,采用了双CPU结构的工作模式,用高速FIFO作为数据交换桥梁.采用FPGA DSP构建系统,DSP用于捷联算法解算,FPGA用于DSP与各类传感器之间的接口,并用软FIFO成功解决了系统中断不够用的问题.最后对光纤陀螺进行了专项测漂与标定,验证了该系统的数据采集和传输的正确性和可靠性.     

基于FPGA和DSP的高速数据采集系统的设计

数据采集与处理系统的设计是现代信号处理系统的基础,被广泛应用于雷达、通信、图像处理、遥感遥测等领域。在对WCDMA数字基带接收机的设计中,提出了一种基于FPGA和DSP的高速数据采集方案。该方案将A/D采样的数据送往FPGA,经过FPGA预处理后送到DSP,最终通过CPCI接口送到主控台。详细介绍了设计思想、具体的硬件连接以及FPGA设计的仿真结果。     

基于V/F变换的高精度寻北仪信号处理系统设计

为提高寻北仪精度,设计了基于V/F变换的数据采集及信号处理系统。陀螺输出的微弱信号通过解调放大电路、专门的V/F变换电路和基于FPGA的信号处理电路,配以软件滤波算法,最终得到较精确的数据采集和处理结果。试验结果表明,该方法能有效去除陀螺输出信号中的噪声,采集的数据用于寻北仪解算能够得到精度较高的寻北结果。     

基于Visual C++的光纤陀螺多参数自动化测试系统

设计了一套基于Visual C++的光纤陀螺多参数自动化测试系统,包括USB接口通信、数据实时显示和存储、数据自主分析、自动生成Word测试报告4个主要功能模块。USB接口通信模块主要完成基于USB接口的数据采集（采用可编程阵列(FPGA)和USB控制芯片实现）,并将数据传输至PC机;数据实时显示和存储部分利用NI公司的Measurement Studio插件实现,主要用于实时显示陀螺数据及数据存储;数据自主分析部分实现了针对光纤陀螺数据的特征分析;自动生成Word测试报告部分实现了针对光纤陀螺多种参数的自动化的计算及测试报告生成。该系统目前已应用于光纤陀螺生产研究中,经多次测试,结果证明其自动化程度高,性能稳定。     

基于FPGA与DSP的H.263硬件电路设计

介绍了以 DSP与 FPGA为核心的 H.2 63的硬件实现电路 ,电路功能主要由图像采集、处理、传输、显示等部分组成。在该硬件系统中 ,主要采用了 TI公司的图像处理 ASIC、高性能浮点运算数字信号处理器 (DSP)tm s3 2 0 c6711,以及 Xlinix公司的 FPGA。其中 ,FPGA实现 ASIC之间的接口电路 ,DSP实现图像数据的 H.2 63编解码。     

数字声波测井的数据采集与处理电路设计

针对多通道数字声波数据采集时序控制复杂的特点,设计了一种基于DSP和FPGA的声波数据采集与处理电路。该设计采用每个通道设计由独立的ADC转换模块进行处理,同时使用单片DSP和单片FPGA进行数据汇总和协调处理,设计中在FPGA内部构造2个双端口RAM作为模数转换器和DSP之间的数据缓存器,电路协调一致地完成4路信号的...     

DSP EMIF与FPGA双口RAM高速通信实现

现代电子技术的快速发展使得大量的数据需要处理与传输,为解决该问题,通过TMS320C6455的EMIF接口实现了DSP与FPGA之间的数据双向快速通信。FPGA通过EMIF接口将内部RAM中的数据传输给DSP进行处理,DSP将处理后的数据结果再通过EMIF接口传送到FPGA的片内接收模块双口RAM并进行存储。EMIF通道实现了对数据的传输,双口RAM完成了对数据的接收。实验结果表明,该设计方案能够实现数据的双向快速正确传输。     

基于EPGA与DSP的H．263硬件电路设计

介绍了以DSP与FPGA为核心的H．263的硬件实现电路，电路功能主要由图像采集、处理、传输、显示等部分组成。在该硬件系统中，主要采用了TI公司的图像处理ASIC、高性能浮点运算数字信号处理器（DSP）tms320c6711,以及Xlinix公司的FPGA。其中，FPGA实现ASIC之间的接口电路，DSP实现图像数据的H．263编解码。     

基于频率解调的半球谐振陀螺控制系统设计

与力平衡模式相比,半球谐振陀螺的全角模式具有测量范围大及线性度高等优点。该文针对现有全角模式解调方案里驻波方位角计算过程中存在的精度损失,以及输出对温度变化敏感等问题,以行波线性叠加原理为基础,提出基于顺时针、逆时针行波同步频率解调的半球谐振子驻波信息解算方法。设计基于频率解调的全角模式半球谐振陀螺多回路控制方法,实现驻波的频率、幅度及正交控制。针对现场可编程门阵列(FPGA)电路算法优化难及浮点运算精度低等问题,设计并实现了现场可编程门阵列+数字信号处理(FPGA+DSP)双核心半球谐振陀螺数字控制电路。通过实物实验验证了该文提出的控制方案及数字控制电路的有效性。实验结果表明,此方法可减小由温度波动引起的谐振频率改变对陀螺输出的影响。     

基于ADSP TS201的雷达通用信号处理板的设计

为了缩短信号处理系统的研发周期,需要一个通用的信号处理硬件平台,只通过设计软件就可以满足不同雷达系统的需求。采用高性能DSP和FPGA为主要芯片设计通用信号处理板,多片DSP通过链路口及总线共享的方式,可以同时进行数据的交互和处理,运算能力强。 FPGA与DSP之间也具有链路口及总线通道,可以将多种接口形式的数据通过转换与DSP进行数据交换。 DSP和FPGA相结合既满足了信号处理的数据处理能力,又拥有多种数据接口方式,适合不同雷达系统信号处理的应用,具有一定的通用性。     

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.