超声波测距模块的设计与实现

本文设计并实现了一个以MCS-51单片机为核心的超声波测距模块.该模块由超声波发射单元、超声波接收单元、温度测量单元、显示单元和ISP下载单元等组成,由单片机产生超声波的发射信号并对其传播时间进行测量,依据超声波在空气中的传播特性,换算出距离数据,从而实现测量距离的目的.设计中采用LM386作为超声波的发射驱动,采用集...     

一种超声波测距传感器温湿度补偿装置

针对现有超声波测距传感器测量精度受温湿度影响的缺点,提出并实现了一种对温度和湿度同时进行补偿的超声波测距传感器温湿度补偿装置,通过对温度和湿度的补偿在一定范围内提高了超声波测距传感器的测量精度.     

基于ARM单片机的自动测高测距小车的研究与设计

生活中许多目标的高度和水平距离需要进行测量。目前主要的测量方法,仍以传统的皮尺丈量为主,测量效率不高,有时还很不方便,没有技术成熟的数字式测高测距产品。以基本的数学方法为理论依据,利用遥控小车做为载体,采用角度传感器测量角度、霍尔传感器测量水平距离等,通过单片机LM3S615进行数据计算,实现了对待测目标物体的高度、水平距离等数据的快速、精确和数字式的测量,高度测量精度可达99.06%,水平测量精度则可达98.06%。     

基于M2080-FNU20的雕刻机超声测距与保护系统

针对电路板雕刻机存在的没有距离显示和超限保护的具体情况,讨论了利用嵌入式工控模块所实现的系统硬件和软件设计.给出了超声测距的原理分析,采用超声波物位变送器实现高精度距离测量.     

基于超声波的移动测距系统设计

该系统是以空气中超声波的传播速度为确定条件,利用发射超声波与反射回波的时间差来测量障碍物的距离。本设计主要分为硬件模块和软件模块。以智能小车为平台来实现移动测距,采用PWM控制直流电机,采用AT89S52单片机进行控制及数据处理,该测距系统主要由超声波发射电路、超声波接收电路、单片机控制电路、寻迹电路、温度补偿电路、直流电机驱动电路及显示电路构成。利用所设计出的超声波测距系统,对不同的距离进行了测试,并进行了误差分析。最后对测距系统进行了验证。实验表明,该系统对室内有限范围内的障碍物距离测量具有较高的精度和可靠性。     

基于单片机的倒车雷达的设计

为降低汽车倒车时的碰撞事故,提出了一种基于单片机的超声波测距倒车雷达的设计方案。该设计根据超声波测距原理,采用AT89S52单片机为控制核心,设计了超声波测距倒车雷达,并对测量距离误差进行了分析。测量距离为0.1～5.0 m,其精度经过校正后可达1 cm。该设计结构简单、工作可靠,有良好的测量精度和灵敏度。     

超声波测距系统的工作原理与应用设计

随着科学技术的飞速发展,超声波在生产、生活中的应用范围越来越广。目前,离生活最近的超声波应用就是测距。如泊车辅助系统、智能导盲系统、移动机器人等距离测量都会用到超声波测距。同时,超声波测距技术还能够实现对障碍物距离的精确测量。文章的超声波测距设计,充分认识到超声波在介质中良好的指向性,因此本次设计正是利用这个优点来实现对前方物体距离的测量。     

基于多传感器的礼仪机器人测距系统的研发

为了提高礼仪机器人在复杂环境中测量数据的可靠性以及解决同一类型多传感器测距盲区无法补偿的问题,使得礼仪机器人可以测得300cm以内障碍物的距离信息,本设计采用红外传感器和超声波传感器组成礼仪机器人的测距系统,并应用自适应加权数据融合技术对传感器所测数据进行融合,实现了两种传感器在功能上的互补,提升了系统的实时性,减小了系统的测距误差。实验结果表明系统可在300cm以内精确测距,提高了整体测距精度,得到了被测距离更加准确的估计。     

基于STC89C52单片机的超声波液位测量仪系统设计

生产生活中离不开距离测量,超声波测距传感器具有成本低、性能好的特点,因此应用较广。该文通过对国内外现状及发展趋势分析,从实际测量问题出发,设计了一款超声波液位测量装置。该装置主要利用"回波测距"原理,配合STC89C52单片机、复位电路、晶振电路、显示电路等硬件部分和相应的程序软件部分来实现。实现了实时显示液面高度并在超出警戒值时自动报警的功能,完全满足业界对液面测量的需求。     

基于单片机带温度补偿的超声波测距仪设计

为了克服超声波测距系统中环境温度波动对系统的测距造成的误差,设计实现了一种AT89S52单片机为核心的超声波测距系统,由DS18B20温度传感器、超声波传感器HC-SRF05以及LCD1602显示电路组成。文中对该系统的硬件组成和软件控制流程中的关键点进行了阐述。实验结果表明,该测距系统稳定可靠、测量精度高,并有一定的实用性和推广价值。     

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.     

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks