【正文】 成，包括計算機、應(yīng)用軟件和儀器硬件，計算機及其測量儀器硬件模塊組成了虛擬儀器硬件平臺的基礎(chǔ)。 (2)數(shù)據(jù)分析與處理 ： 虛擬儀器充分利用計算機的存儲、運算功能，并通過軟件實現(xiàn)對輸入數(shù)據(jù)信號的分析與處理。 (2)軟件設(shè)計 ： 主要采用 LabVIEW 設(shè)計 ，虛擬儀器的界面開發(fā)主要由 LabVIEW 軟件完成，其實現(xiàn)數(shù)據(jù)的采集、處理、分析等人機交互的界面設(shè)計。它的功能包括函數(shù)數(shù)值運算、數(shù)據(jù)采集、數(shù)據(jù)分析、信號生成、信號處理、輸入和 輸出控制，以及圖像 3 獲取、處理和傳輸?shù)鹊取?我國在虛擬儀器方面，起步較為緩慢，只是部分院校實驗室引進虛擬儀器系統(tǒng)。因此，研制一種結(jié)構(gòu)簡單、操作方便、費用低的虛擬示波器是非常必要的。 關(guān)鍵詞 虛擬儀器 ， 虛擬示波器 ， 頻域分析 ，數(shù)據(jù)采集 ABSTRACT In the contemporary world, information and puter technology develop rapidly with each passing day. The Software Development Technology is quite different, too. Compared with the traditional instrument technology, the virtual instrument technology based on puter has more advantages from the aspects of data acquisition, realtime analysis and processing, display and storage. Because of traditional instruments’ single function and high price for always and the continuous improvement of puters’ cost performance, the technology of virtual instrument is irreversible. The NI (National Instrument) took the lead in the technology of virtual instrument research and development, and established the LabVIEW software development platform. The technology of puterassisted virtual instrument promoted the traditional instruments to the direction of intelligent, digitizing, working, modular and userfriendly. This article, based on LabVIEW virtual instrument development platform, design virtual oscilloscope interface and realize the function of data acquisition, filtering process, time domain analysis, frequency domain analysis, waveform storage and recall, and debug program, illustrate design results, analyze the system performance. KeyWords: Virtual instrument, Virtual oscilloscope, Frequency domain analysis, Data acquisition 目 錄 1 緒論 .............................................................................................................................. 1 前言 .................................................................................................................... 1 設(shè)計背景與意義 ................................................................................................... 1 國內(nèi)外現(xiàn)狀 .......................................................................................................... 2 設(shè)計研究方案 ...................................................................................................... 2 ................................................................................................................ 3 虛擬儀器系統(tǒng)的組成 ............................................................................................ 4 虛擬儀器的構(gòu)成 ................................................................................................... 5 虛擬儀器的硬件系 ...................................................................................... 5 虛擬儀器的軟件系統(tǒng) .................................................................................. 5 虛擬儀器與傳統(tǒng)儀器優(yōu)缺點對比 .......................................................................... 6 的軟件概述 .................................................................................................... 7 軟件的特點 ........................................................................................... 7 LabVIEW 程序的構(gòu)成 .......................................................................................... 8 LabVIEW 的操作選板 ........................................................................................ 10 4 傳統(tǒng)示波器與虛擬示波器 ............................................................................................ 12 傳統(tǒng)示波器 ........................................................................................................ 12 傳統(tǒng)示波器工作原理 ................................................................................ 13 傳統(tǒng)示波器的分類 .................................................................................... 14 虛擬示波器 ........................................................................................................ 14 虛擬示波器的組成結(jié)構(gòu) ............................................................................. 15 虛擬示波器的性能指標(biāo) ............................................................................. 15 傳統(tǒng)示波器與虛擬示波器對比 .................................................................. 16 ................................................................................................ 17 數(shù)據(jù)采集模塊 .................................................................................................... 18 數(shù)據(jù)采集系統(tǒng)的構(gòu)成 ................................................................................ 19 采樣原理 .................................................................................................. 20 用戶登陸界面 .................................................................................................... 21 虛擬示波器主界面 ............................................................................................. 23 濾波模塊 ........................................................................................................... 26 時域分析與參數(shù)測量模塊 ................................................................................... 28 頻譜分析模塊 .................................................................................................... 29 波形存儲和回放 ................................................................................................ 30 ............................................................................................ 32 程序調(diào)試 ........................................................................................................... 32 虛擬示波器數(shù)據(jù)顯示 .......................................................................................... 33 噪聲干擾的防止方法 .......................................................................................... 37 7 總結(jié)與展望 ......................................................................................................