Based On Virtual Instrument Technology Of Automatic Test And Measuring Equipment Research And Development,

The instrumentation industry is undergoing a variety of exciting changes as a result of the rapidly development of computer techno logy micro-electronics technology and communication technology. Traditional instruments are almost composed of hardware or fixed-software, which is hardly satisfied the needs of the rapidly development of new technology. In order to solve this problem, the NI(National Instrument) Corporation bring forward the term "virtual instrument" and the slogan "software are instruments". With making use of the powerful calculation ability of computer, and composing of some necessary hardware, The "virtual instrument" break the limit of traditional instrument's abilities in field of calculation DSP display and so on. It bring a enormous transform in instrumentation community. Virtual instrument describes the combination of programmable instruments with general-purpose PCs.The system discussed in this paper, TACAN automatic test system, is based on the virtual instrument technology. The design process of virtual instrument is learned by the TACAN automatic test system. Firstly, the base concept of virtual instrument is introduced, and virtual instrument have been compared with traditional instrument, the development of virtual instrument is also discussed. Secondly, the concept of TACAN system is introduced, especially the VOR(Very high frequency Omni-directional Range) composite signal is discussed in details. Thirdly, the design process and constitutes of TACAN automatic test system are discussed in details, focus on the design idea of collectivity and realization of hardware and software. The method of how to design a virtual instrument in PCI-DAQ(Data AcQuisition) mode is also introduced. All functions of this system satisfied requirements and passed the test. It can test the TACAN components automatically, and display the advances compared to traditional instruments.