基于RFID的嵌入式系统设计与实现

<正>一、RFID技术概述RFID是Radio Frequency Identification的缩写,即自动识别技术的一种,通过无线射频方式进行非接触双向数据通信,对目标加以识别并获取相关数据。射频识别的主要核心部件是读写器和电子标签,电子标签可以接收相距几厘米到几米距离内的读写器发射的无线电波,而读写器可以读取电子标签内     

无线射频识别技术（RFID）应用与发展

文章概述了无线射频识别技术(RFID)原理和应用领域,评述了电子标签天线的制造方法。     

无源超高频电子标签射频模拟前端设计

基于对射频识别技术（RFID）物理基础的介绍,并阐述射频识别技术（RFID）的作用范围,介绍了无源超高频电子标签射频模拟前端设计的实现原理框图。通过对ISO 18000.6B协议相关规定的分析,合理地确定了模拟前端和射频前端各个模块的设计指标,并就这些规定的指标设计出了中心频率为915MHz的无源超高频电子标签芯片射频模拟前端。     

基于物联网的RFID电子标签研究进展

概述了国际上射频识别标准组织的发展过程,总结了电子标签的关键技术和发展前景,提出了基于物联网的射频识别(RFID)电子标签实施策略。目前信息技术已经从人与人的通信,逐步扩展到人与物、物与物的通信,国际上对物品的自动识别技术发展很快,RFID电子标签扮演了重要角色。电子标签是实现物联网的基石,可以实现对物品的透明化追踪,但也带来了数据碰撞、保密性差等问题,通过采用防冲突机制和加密技术等,可以有效解决这些问题。利用RFID电子标签实现物品识别具有十分重要的意义,可以极大推动物联网的发展,使信息技术发生根本性变革。     

浅析RFID射频识别技术

RFID射频识别技术是利用射频信号使读写器与电子标签能够相互通信,实现读写器对电子标签的识别。RFID系统采用电感耦合和电磁耦合两种工作方式对电子标签进行识别。该系统包括天线、读写器、电子标签、中间件、系统应用软件等子系统,在系统设计时要注意各子系统间的兼容性。     

RFID 有源电子标签节能技术研究

在对RFID有源电子标签节能常规解决方法中存在的弊端进行分析的基础上,提出了利用感应器切换RFID有源电子标签的工作模式和对RFID有源电子标签根据不同应用场景设置不同休眠策略的办法,有效减少RFID有源电子标签射频发送次数,达到节约能量的一种新的节能技术。以典型应用详细说明了电子标签进出出入口方向的准确判定和休眠时间策略设置方法,并介绍了在重要物品管控系统中利用新节能技术研发的感应器、RFID有源电子标签的功能、组成、软件设计,从而验证新的节能技术能应用于RFID有源电子标签系统中。     

可穿戴无线体温监测RFID电子标签

本文设计了一种无源超高频(UHF)可穿戴射频识别(RFID)电子标签,可实现对人体体温的无线监测.传统超高频RFID电子标签,只能对物品的身份信息进行识别,而无法对生物体征(如体温、血压、心率)进行识别.近几年来随着物联网的逐渐普及,对健康医学领域的实时监测的需求也在逐渐增加.本文基于RFID识别传感一体化技术,提出了...     

基于有源RFID物联网的物资跟踪管理及追溯系统设计与实现

为了方便对贵重物资的储运过程进行实时跟踪管理,分析了物资存储和运输过程中普遍存在跟踪及追溯的实时性、准确性等问题,设计了以有源射频识别(RFID)为感知层的物联网物资跟踪管理及追溯系统。该系统通过对电子标签上的物资信息的读写,能够对附有电子标签的物资进行跟踪管理,结合地理信息系统(GIS)软件展示物资定位信息,最后通过Visual Studio工具及SQL Server 2005数据库系统进行系统管理软件开发。与传统无源RFID相比,该系统采用2.4GHz有源RFID克服了传统射频识别技术读写距离短的问题,能够同时读写多个电子标签,并采用低功耗技术延长了电子标签的使用时间,实现了存储过程中管理的便利性及运输过程中物资的可追溯性,具有数据采集便利、速度快,实时性和直观性强等特点。     

面向中长跑体能测试的RFID设计与实现

将RFID无线射频技术应用于中长跑的体能测试计时,以我国标准400 m跑道为例设计RFID自动计时系统的无线阅读器布局,使用频率为2.4 GHz的阅读器对电子标签进行识别。针对基于RFID的中长跑自动计时系统的无线阅读器和电子标签进行硬件设计,并使用帧时隙ALOHA算法实现多个运动员同时进入阅读器识别范围内的防碰撞处理。使用定位算法对阅读器识别范围内的运动员进行定位,确定运动员成绩。最后通过实验方法验证基于RFID的中长跑自动计时系统。     

基于电子纸技术的无线电子标签研究

RFID电子标签技术即无线射频识别技术,是一种非接触式的自动识别技术。首先介绍无线电子标签的工作原理和应用特点,以及电子纸的驱动显示技术,针对一种常用的无线电子标签设计感应模块和数据存储处理模块,并提出一种新型应用。     

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.