Study On Networked Virtual Instrument And Application Of It In PDA

The virtual instrument technique has vitality only keep up with the progress of information technology. The invention and widely application of virtual instrument which is caused by computer technology has made a technical revolution in measuring and control. Computer and communication network develop rapidly in recent two decade and has been applied to every walk of life. Network and virtual instrument combine to networked virtual instrument which is widely used in remote teaching and experiment, networked data collection and control, sharing remote instruments, remote fault diagnose, remote measurement, remote monitor.The performance/cost ratio of PDA (Personal Digital Assistant) is increasing with the development of embedded technology. Pocket virtual instrument is a result of applying virtual instrument and networked virtual instrument technology to PDA. Pocket virtual instrument is light, small, portable and can equip with wireless communication. Thus test and measurement task become more free and more convenient.Networked and pocket virtual instrument is the most importance direction in the development of virtual instrument, have market potential and application foreground. It is valuable and significance for studying networked and pocket virtual instrument technique and for developing virtual instrument products. The study for this are showed in detail as follows:1) Deeply study networked virtual instrument and its realization technology. From networked data acquisition, networked data management, networked data analyze, networked data sharing and release to form of networked virtual instrument.2) Applying virtual instrument and networked virtual instrument concept and technology to PDA, we give the concept of pocket virtual instrument and build its technique system.3) The ways to apply WLAN, BLUETOOTH, IrDA, GPRS to pocket virtual instrument are discussed. Those wireless technologies can enhance facility of virtual instrument.4) Study the way that applying Web Services to virtual instrument.5) The developing toolkit of pocket virtual instrument based on VS.NET consists of virtual instrument controlling panel library, analyzing library and data transmittinglibrary which are seamless integrated with VS.NET by plug-in. The applications of networked virtual instrument based PDA can be rapidly develop with this toolkit.6) The data stream compress library based PDA has been developed which can be combine application to compress data, reduce size of data and transfer time.7) Pocket data logger, Mobile temperature monitor, Pocket FFT analyzer, Pocket wavelet analyzer are built using the developing toolkit of pocket virtual instrument.