虫虫首页| 资源下载| 资源专辑| 精品软件
登录| 注册

PAPER reading

  • 提高在噪声环境下的磁卡读写器(MCR)系统

    Abstract: Most magnetic read head data sheets do not fully specify the frequency-dependent components andare often vague when specifying other key parameters. In some cases, the specifications of two very similarheads from two different manufacturers might be quite different in terms of parameters specified and omitted.The limitations in the data sheets make designing an optimum card reading system unnecessarily difficult andtime consuming. This document outlines a strategy to overcome the above shortcomings and offers guidelinesto overcome the noise issues.

    标签: MCR 噪声环境 磁卡读写器

    上传时间: 2013-11-13

    上传用户:dysyase

  • 三电平变换器STATCOM空间矢量调制

    This paper presents a space vector modulation(SVM)-based switching strategy for a three-level neutral point clamped (NPC) converter that is adapted as a STATCOM.

    标签: STATCOM 三电平 变换器 空间矢量

    上传时间: 2013-10-20

    上传用户:zyt

  • 水声信号功率放大器的设计与实现

    设计了水声信号发生系统中的功率放大电路,可将前级电路产生的方波信号转换为正弦信号,同时进行滤波、功率放大,使其满足换能器对输入信号的要求。该电路以单片机AT89C52,集成6阶巴特沃思低通滤波芯片MF6以及大功率运算放大器LM12为核心,通过标准RS232接口与PC进行通信,实现信号增益的程控调节,对干扰信号具有良好的抑制作用。经调试该电路工作稳定正常,输出波形无失真,在输出功率以及放大增益、波纹系数等方面均满足设计要求。    This paper presented a design and implementation of underwater acoustic power amplifer. This circuit converted the rectangle signal generated by frontend circuit into the sine signal, then filtered and power amplification, it meets the requirements of the transducer.Included AT89C52, 6th order Butterworth filter MF6, hipower amplififier LM12.Communication with PC through the RS232 port. The signal gain is adjustable and could be remote controlled. It has a good inhibitory effect on the interference signal. After debugged, this circuit works stable, the output waveform has no distortion, it meets the design requirement in outprt power, amplifier gain and ripple factor.

    标签: 水声信号 功率放大器

    上传时间: 2013-11-20

    上传用户:qwe1234

  • 射频集成电路设计John Rogers(Radio Freq

    Radio Frequency Integrated Circuit Design I enjoyed reading this book for a number of reasons. One reason is that itaddresses high-speed analog design in the context of microwave issues. This isan advanced-level book, which should follow courses in basic circuits andtransmission lines. Most analog integrated circuit designers in the past workedon applications at low enough frequency that microwave issues did not arise.As a consequence, they were adept at lumped parameter circuits and often notcomfortable with circuits where waves travel in space. However, in order todesign radio frequency (RF) communications integrated circuits (IC) in thegigahertz range, one must deal with transmission lines at chip interfaces andwhere interconnections on chip are far apart. Also, impedance matching isaddressed, which is a topic that arises most often in microwave circuits. In mycareer, there has been a gap in comprehension between analog low-frequencydesigners and microwave designers. Often, similar issues were dealt with in twodifferent languages. Although this book is more firmly based in lumped-elementanalog circuit design, it is nice to see that microwave knowledge is brought inwhere necessary.Too many analog circuit books in the past have concentrated first on thecircuit side rather than on basic theory behind their application in communications.The circuits usually used have evolved through experience, without asatisfying intellectual theme in describing them. Why a given circuit works bestcan be subtle, and often these circuits are chosen only through experience. Forthis reason, I am happy that the book begins first with topics that require anintellectual approach—noise, linearity and filtering, and technology issues. Iam particularly happy with how linearity is introduced (power series). In therest of the book it is then shown, with specific circuits and numerical examples,how linearity and noise issues arise.

    标签: Rogers Radio John Freq

    上传时间: 2014-12-23

    上传用户:han_zh

  • CTP知识全解

      1.什么是CTP?   CTP包括几种含义:   脱机直接制版(Computer-to-plate)   在机直接制版(Computer-to-press)   直接印刷(Computer-to-paper/print)   数字打样(Computer-to-proof)   普通PS版直接制版技术,即CTcP(Computer-to-conventional plate)   这里所论述的CTP系统是脱机直接制版(Computer-to-plate)。CTP就是计算机直接到印版,是一种数字化印版成像过程。CTP直接制版机与照排机结构原理相仿。起制版设备均是用计算机直接控制,用激光扫描成像,再通过显影、定影生成直接可上机印刷的印版。计算机直接制版是采用数字化工作流程,直接将文字、图象转变为数字,直接生成印版,省去了胶片这一材料、人工拼版的过程、半自动或全自动晒版工序。

    标签: CTP

    上传时间: 2013-10-27

    上传用户:baiom

  • 双x波段电压控制振荡器研究

    In this paper, two types of MMIC voltage controlled oscillators have been successfully demonstrated. The first chip with single tuning diode shows the excellent tuning linearity. The second chip with two tuning diodes can improve the tuning bandwidth.

    标签: 波段 振荡器 电压控制

    上传时间: 2013-10-17

    上传用户:xjz632

  • 电网现场作业管理系统的信息化设计

    为了改变目前电网现场作业管理的变电巡检、变电检修试验、输电线路巡检检修等管理系统各自独立运行,信息不能共享,功能、效率受限,建设和维护成本高的现状,提出了采用B/S+C/S构架模式,将各现场作业管理模块和生产MIS(管理系统)集成为一体的现场作业管理系统的设计方案,做到各子系统和生产MIS软硬资源共享,做到同一数据唯一入口、一处录入多处使用。各子系统设备人员等基础信息来源于生产管理系统,各子系统又是生产管理系统的作业数据、缺陷信息的重要来源。经过研究试用成功和推广应用,目前该系统已在江西电网220 kV及以上变电站全面应用。 Abstract:  In order to improve the status that the substation field inspection system, substation equipments maintenance and testing system, power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency, and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode, integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS,the field work data of the sub systems are the source information of MIS, by which the same single data resouce with one-time input can be utilized in multiple places. After the research and testing, this system is triumphantly using in all 220kV and above substations in Jiangxi grid.

    标签: 电网 信息化 管理系统

    上传时间: 2013-11-15

    上传用户:han_zh

  • 基于微网的光伏变流器系统设计

    光伏发电是未来新能源发电重要方向之一,而光伏变流器是光伏发电系统的核心。介绍一种基于微网理念的光伏变流器设计。以该变流器为核心的光伏发电系统可以看做一个小型的微网系统。该系统能根据外部电网情况,工作于并网模式和离网模式。介绍了该系统的各个组成部件的设计以及变流器主电路部分器件的选型。最后,由实验样机进行测试。试验结果验证了电路拓扑结构及控制方案的可行性,也说明了系统参数设计方法的正确性。 Abstract:  Solar Photovoltaic generation is an important direction of new energy power generation in the future,while photovoltaic converter is the core of photovoltaic generation system. This paper deals with a study on photovoltaic inverter based on the concept of microgrid. This paper describes a system whose core component is the photovoltaic inverter,can work on grid-connected mode or run independently according to the external situation. The paper simply describes the main components of the system. At last,the prototype was produced and tested. Test result has proved feasibility of circuit topology structure and controlling scheme and shown correctness of system parameters.Key words: PV inverter; microgrid; off-grid; storage battery

    标签: 光伏 变流器 系统设计

    上传时间: 2014-12-24

    上传用户:Shaikh

  • 无线通信网络基本概念及设计

    This white paper raises some fundamental issues the design engineer should address before deciding upon a communication approach for a wireless network. As no universal wireless network solution exists, it should be custom tailored to suit the application demands. Defining your application communication characteristics is the key to ensure optimal communication reliability and resistance to interfering noise sources.

    标签: 无线通信网络 基本概念

    上传时间: 2013-11-23

    上传用户:zhichenglu

  • 基于AVR的PCB板雕刻机的设计

      为了提高PCB板制作的效率,改变传统的化学腐蚀制板工艺,使用机械仿形铣制作电路板的方法,设计了以ATMEGA16单片机为核心部件的PCB板雕刻机控制系统。其中包括PCB雕刻机的基本功能、主要硬件电路设计和软件的实现流程,并给出了相关设计电路。重点分析了雕刻机步进电机的驱动电路以及主轴电机的驱动电路,该雕刻机经实际运行,系统工作良好,可有效提高PCB板的制作效率。   Abstract:   In order to improve the efficiency of production of PCB board and change the traditional chemical etching plates, using of mechanical copying milling method makes circuit boards,this paper introduces the PCB engraving machine control system used ATMEGA16 microcomputer as the core components. It includes basic function, the hardware circuit design and software realization process, and gives the corresponding circuit design.It analyses the drive circuit of engrawing machine stepper motor and spindle motor in detail. This engraving machine by practical operation, the system works well, which can effectively improve the production efficiency of PCB board.

    标签: AVR PCB 雕刻机

    上传时间: 2013-10-17

    上传用户:liangliang123