一种光传感器高性能放大电路的设计研究

以物联网应用为背景,根据光传感器放大电路的应用场景和特点设计放大电路,得出了制作传感器放大电路的理论依据、设计方法、电路改进措施等。采用计算加实验的方法,在给出一系列设计技巧、注意事项和经验的基础上,研究出了一种使用CMOS型集成运算放大器等新型器件制作的光传感器高性能放大器的实际电路。基于三级级联的方式,该放大器具有灵敏度高,波动性好,低能耗,微型化等特点。     

嵌入式传感器节点设计及其应用

针对现有物联网应用中传感器节点的设计存在大量重复开发、扩展能力不强等不足,以高性能的STM32微处理器和uC／OS-11嵌入式实时操作系统为核心,采用Zigbee无线通信技术,设计了一种具有高扩展能力的通用嵌入式传感器节点。该传感器节点提供多样化的传感器和外扩功能接口,方便各种传感器的连接和功能的扩展。在uC／OS-11嵌入式实时操作系统的支持下可快速搭建面向物联网研究和应用的专用传感器节点。实际应用测试表明,节点良好地实现了高性能、低功耗、高扩展能力和复用性的设计目标,为加快物联网的开发和应用打下了良好的基础。     

基于1-wire总线的温度传感器网络

温度传感器网络广泛应用于工业农业等场合中。1-wire总线技术与传感器技术的结合简化了被测对象的监测网络设计。采用1-wire总线技术构成的传感器网络为大型的传感器网络提供了很好的前端采集网络构建方案。在分析了各种设计方案后，提出了以AT89C51单片机为主控芯片、以DS18820为测温节点的1—wire总线温度传感器网络的设计方案，详细分析了设计流程，并给出了部分设计代码。引入用户按键和定时器，将用户的参与与无人值守的智能性进行有效的结合。为1-wire总线式传感器网络的应用设计提供了参考。     

基才51单片机的酒精浓度检测仪的设计

为了能有效防患因驾驶员酒后驾车而造成的事故发生,设计一种以智能仪器能够监测驾驶员呼出气体酒精含量非常必要。本设计以51单片机和MQ-3气体传感器为核心,设计了系统硬件电路,阐述了各模块功能并着重研究了气体传感器的选择。该系统能提供检测、显示、报警等多种功能,具有成本低、体积小、智能化强的特点。     

基于ZigBee的煤矿监控网络节点设计

针对矿用监控设备采用有线方式传输信号存在的弊端,煤矿实时监控采用基于Zigbee的无线传感器网络技术.根据无线传感器网络工作原理和节点体系架构,设计了以CC2430为核心的传感器网络节点.该节点装置能够完成瓦斯浓度监测、井下人员的实时信息采集和定位等,并详细给出了这种传感器节点的硬件设计和软件流程.     

基于CAN总线的联合收割机智能控制系统的设计与实现

本文介绍了一种以P87C591单片机为主控器,以谷物流量传感器、谷物湿度传感器、割台高度传感器、地速传感器、升运器转速传感器、DGPS接收机、变量作业控制和智能控制终端为主要外围元件的联合收割机智能控制系统。此系统具有显示直观、准确,使用方便、可靠等优点,代表了联合收割机智能控制系统的最新发展趋势。在系统设计过程中充分考虑了性价比,选用价格低、性能稳定的元器件。通过运行调试,试验结果与设计要求基本一致。     

一种通用型无线传感器节点架构

以MSP430F169芯片为控制核心,设计了构建通用型无线传感器网络的传感器节点和汇聚网关。传感器节点具有很强的扩展性,提供了I2C、UART、SPI以及模拟信号等四种接口类型,可以挂接主流的商用传感器,完成光强、温湿度、PH值、地理位置等数据的实时采集.采集的数据以无线通信方式传至汇聚网关,进而以有线的方式传到数据中心。传感器节点和汇聚网关之间的数据和指令交换采用NRF24L01射频模块来实现。现场测试证明传感器节点采集的数据是可靠的,能稳定地传回至汇聚网关。     

基于磁敏角度技术的拉线式位移传感器的设计与应用

介绍MLX90316的结构和特性,设计以LPC2136为CPU,MLX90316为位置反馈的拉线式位移传感器,给出了基于MLX90316的位移检测策略,并详细分析了接口电路原理图和编程原理。该传感器具备一路RS485通信链路和一路基于PWM可调电流输出。试验证明,该传感器克服传统拉线式位移传感器的易磨损、分辨力差、阻值偏低、高频特性差等缺点,提高了测量精度。     

外逸电子传感器8031单片机控制系统设计

基于传感器智能化的设计思想,提出以８０３１单片机为核心传感器计数控制系统。该系统主要由定时／计数同步电路、ＬＣＭ接口电路和光电隔离电路等组成。实验结果表明,系统设计合理,体积小、实时处理速度快和控制精度高,从而为外逸电子传感器的智能化奠定了良好的基础。     

基于DSP和双目视觉的多媒体传感器网络节点设计与实现

针对无线传感器网络对于多媒体信息获取的实际需求,以高性能DSP处理器为核心,结合ZigBee无线通信,设计实现了新型多媒体无线传感器节点。借助DSP的强大运算能力和外设接口,在多媒体节点上配置了双目摄像机、加速度计等传感器,实现了环境信息和图像数据的实时感知与获取,并依托ZigBee协议形成了室内环境短距无线通信与监测能力。实验结果表明,所设计的多媒体传感器节点能够准确、实时地进行综合感知数据的获取与处理,满足无线多媒体传感器网络的应用需求。     

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.