基于LabVIEW的数字示波器的设计

I摘要众所周知，示波器是测量电子信号的波形的一种仪器，它可以分析计算出波形的各种参数，包括频率、周期、电压等。以往的示波器在某些方面都存在些许不足之处，而利用近年来出现的图形化编辑环境LabVIEW即虚拟仪器的这个平台则可以完善老式示波器的不足，其优势在于可以由用户自己来选择与定义仪器的功能，能更高效率地完成新产品的研发，满足多样化需求。借助PC机的强大功能，将虚拟仪器的硬件和软件相结合，以完成虚拟示波器的设计。文中介绍了虚拟示波器拟达到的一些技术指标以及设计方案。主要包括数据采集、参数测量、频谱分析、波形显示和波形存储几大模块，可进行数据采集、显示、存储和分析处理，同时显示、记录和存储多通道显示出来的波形，还可以对波形进行数据分析和处理，即完成对模拟信号的数字处理，其中数据采集参数的设置、波形数据存储显示和分析处理都由软件实现，与传统的数字示波器相比，虚拟数字示波器在人性化程度、处理能力、性价比、可操作性等方面都具有明显的优势。关键词：虚拟仪器；LabVIEW；数字示波器；数据采集IIABSTRACTAsisknowntoall,oscillographisakindofelectronicsignalwaveformmeasurementinstrument,itcananalyzethecalculatedwaveformparameters,includingfrequency,cycle,voltage,etc.Previousoscilloscopeisinsomewaystherearesomedeficiencies,andtheuseofLabVIEWgraphicaleditingenvironmentappearedinrecentyearsistheplatformofvirtualinstrumentcanimprovetheshortcomingsofoldoscilloscope,itsadvantagescanbedefinedbytheusertoselectandthefunctionoftheinstrument,canbemoreefficienttocompletethenewproductresearchanddevelopment,meetthedemandofdiversification.WiththeaidofthepowerfulfeaturesofthePC,combininghardwareandsoftwareofvirtualinstrument,tocompletethedesignofvirtualoscilloscope.Thispaperintroducesavirtualoscillographisproposedtoachievesomeofthetechnicalindicatorsandthedesignscheme.Mainlyincludingdataacquisition,parametermeasurement,spectrumanalysis,waveformdisplayandwaveformstorageofseveralmajormodules,dataacquisition,display,storageandanalysiscanbeprocessing,atthesametimedisplay,recordingandstoragemulti-channeldisplaywaveform,canalsobethewaveformdataanalysisandprocessing,thecompletionoftheanalogsignaldigitalprocessing,thedataacquisitionparameterssetting,waveformdisplayanddatastorage,analysisisimplementedbysoftware,comparedwiththetraditionaldigitaloscilloscope,virtualdigitaloscilloscopeinthedegreeofhumanization,capacity,costperformance,operability,etchaveobviousadvantages.Keywords：virtualinstrument;labview;digitaloscilloscope;datacollectionIII目录1绪论............................................................11.1研究背景与意义.............................................11.2数字示波器的发展状况.......................................11.3虚拟仪器...................................................31.3.1虚拟仪器简介........................................31.3.2虚拟仪器与传统仪器对比...........................................................31.4研究内容...................................................31.5文章结构安排...............................................42虚拟数字示波器设计方案...........................................52.1LabVIEW....................................................52.1.1LabVIEW简介........................................52.1.2LabVIEW的优势......................................52.2设计方案...................................................52.2.1虚拟数字示波器的设计流程图..........................52.2.2软件设计............................................63数字示波器前面板设计.............................................73.1前面板所需模块.............................................73.1.1数据采集模块........................................73.1.2触发控制模块........................................83.1.3时基模块........................................................................................83.1.4参数测量模块................................................................................83.1.5频谱分析模块................................................................................83.1.6波形显示模块................................................................................83.2总体前面板设计..........................................................................................93.2.1波形显示控制部分........................................................................93.2.2输入信号测量值的显示部分........................................................93.2.3数据存储与读取部分..................................................................103.2.4波形打印部分..............................................................................114数字示波器后面板设计............................................114.1后面板所需模块............................................11IV4.1.1波形显示模块................................................错误!未定义书签。4.1.2输入信号测量值模块..................错误!未定义书签。4.1.3频谱分析模块..............................................................................134.1.4数据采集模块..............................................................................134.1.5数据存储与读取模块..................................................................144.1.6自动扫描控制模块......................................................................154.2总体后面板设计........................................................错误!未定义书签。5虚拟数字示波器的仿真与调试......................................175.1虚拟数字示波器的仿真......................................175.1.1正弦波与三角波的仿真...............................175.1.2通道的选择以及频谱分析.............................175.2结果分析...................................................................................................21结束语.............................................................22参考文献...........................................................23致谢...............................................................2611绪论1.1研究背景与意义传统仪器的功能都由生产厂家给定而用户不可随意改动，仪器笨重不易移动且耗费的资金巨大，技术更新却