虚拟示波器的设计

论文编号:JD247   字数:18009,页数:52,

摘    要
虚拟仪器技术是最近二十年发展的一项新技术，其核心思想是“软件就是仪器”。虚拟仪器利用PC强大的数据处理能力，由用户根据软件定义的界面来操作计算机，完成对被测信号的采集、分析、处理、判断及显示等一系列功能，从而实现仪器的功能。
示波器是在科学研究和高等院校中应用广泛的一种通用仪器。目前研制一种能够满足高等院校科研和教学要求的示波器是非常必要的。虚拟示波器是虚拟仪器技术的一种具体应用。该虚拟仪器基于计算机平台，将虚拟仪器硬件和软件紧密结合，实现比传统仪器更强大的功能。
本文介绍了示波器和虚拟仪器的原理与发展。在此基础上，提出了基于LabVIEW的虚拟示波器设计方案。本虚拟仪器系统由数据采集、数据分析和结果输出显示三个主要功能部分组成。本文介绍了虚拟示波器各模块功能，并给出了具体的设计方法和测试结果。

关键词：LabVIEW 虚拟示波器  PCI-6221

Abstract
The virtual instrument technology is a new technology which developed in recent twenty years .The core idea of virtual instruments is ''The software is the instrument''. The virtual instrument utilizes the PC''s strong data processing ability, operates the computer according to the interface that the software defined, completes a series of function of the signal collecting, analyzing, processing, judging and display, and realizes the function of the instrument.
Oscilloscope is a kind of general instrument extensively used in science research and Universities. It is very necessary to develop a kind of oscilloscope to meet the requirement of scientific research and teaching in universities. The virtual oscilloscope is a kind of application of VI technology. This VI is based on computer. It combines the virtual instrument''s hardware with software close to realize the stronger function than traditional instrument.
This thesis introduced the principle and the development of the oscilloscope and virtual instrument. On this basis, this thesis puts forward the design of the virtual oscilloscope scheme based on LabVIEW. The virtual oscilloscope system includes three main function parts. They are data acquisition, data analysis and output display. This thesis presents a virtual oscilloscope for the function of the module, and gives a specific design methods and text results.

Keywords：LabVIEW  virtual oscilloscope  PCI-6221
目    录
第一章绪论...................................................................1
  1.1 问题的提出.............................................................1
  1.2 示波器概述与发..........................................................2
    1.2.1 示波器概述.........................................................2
    1.2.1 示波器的发展.......................................................3
  1.3虚拟仪器的概述与发展.....................................................4
    1.3.1 虚拟仪器概述.......................................................4
    1.3.2 虚拟仪器的发展.....................................................5
  1.4 本课题研究内容.........................................................7
  1.5 本课题的研究意义.......................................................7
第二章 虚拟示波器的总体设计方案 ...............................................8
  2.1硬件设计..............................................................8
    2.1.1 数据采集卡的选择...................................................8
  2.2软件设计..............................................................13
    2.2.1编程语言选择 ......................................................13
    2.2.2 NI驱动软件的选择..................................................13
    2.2.3虚拟示波器功能设计.................................................15
第三章 LabVIEW软件介绍......................................................17
  3.1 LabVIEW 程序组成.....................................................17
  3.2 LabVIEW编程模板......................................................18
    3.2.1工具选板..........................................................18
    3.2.2控件选板..........................................................18
    3.2.3函数选板..........................................................19
第四章程序设计..............................................................21
  4.1 数据采集模块..........................................................21
    4.1.1 DAQ 助手.........................................................22
    4.1.2通道选择...........................................................23
  4.2波形显示模块...........................................................25
    4.2.1波形图............................................................25
    4.2.2时基控制和幅值控制旋钮..............................................26
  4.3滤波模块..............................................................28
    4.3.1滤波器............................................................28
  4.4参数测量模块...........................................................28
    4.4.1幅值和电平测量.....................................................28
    4.4.2时间与瞬态特性测量..................................................30
    4.4.3频谱测量..........................................................31
  4.5数据存储模块...........................................................32
    4.5.1写入测量文件.......................................................32
  4.6数据回放模块...........................................................34
    4.6.1读取测量文件.......................................................34
  4.7 虚拟示波器前面板......................................................36
  4.8 虚拟示波器程序........................................................37
第五章系统测试..............................................................38
  5.1 虚拟示波器的主要功能...................................................38
  5.2 虚拟示波器的性能指标....................................................38
    5.2.1硬件性能指标........................................................38
    5.2.2软件性能指标........................................................38
  5.3 数据采集和波形显示模块测试...............................................38
  5.4时基控制旋钮测试........................................................41
  5.5 幅值控制测试...........................................................41
  5.6 滤波模块测试...........................................................42
  5.7 参数测量模块测试........................................................44
  5.8 数据存储模块测试........................................................45
  5.9数据回放模块测试.........................................................46
  5.10 系统测试结果..........................................................48
第六章技术经济分析报告........................................................49
第七章结论与展望..............................................................50
参考文献....................................................................51
致谢........................................................................52
声明........................................................................53