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。     

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。     

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。     

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IEEE 1451.3的IPv6网络传感器设计

针对网络环境下的信息获取,研究了传感器网络和IPv6网络之间的融合。结合IEEE 1451网络传感器的设计思想,设计了一个以单总线传感器为基础、以IEEE 1451．3为接口标准的即插即用的IPv6网络传感器。采用MAXIM公司的DS80C400作为网络接口控制器．使传感器网络成功地接人IPv6网络。本文着重介绍了网络控制器的开发,即单总线接口、IPv6网络接口的开发以及虚拟TEDS的设计。     

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.     

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.     

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.     

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.     

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.     

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.