Design Of Simple Virtual Oscillograph

The instrumentation industry is undergoing a variety of exciting changes as a result of the development of PCs, The PC revolution has equipped users with powerful processing and display capabilities of their own. The computer can enhance instrument functionality in any of the three areas-data acquisition, analysis, and presentation. Virtual instrument (VI) changed the ideas of traditional instrument and made full use of the powerful resources of computer. It is a new-style instrument that combines the technologies of electronic measurement, signal processing, computer and network. It has been used widely because of lower cost and convenient application.This thesis introduced the basic framework and design ideas of virtual machines. On this basis, made a virtual oscilloscope-based PC sound card in the system design. The article focused on the simple virtual oscilloscope modules of the detailed design, including data collection and processing, trigger control, waveform display, measuring parameters, spectrum analysis, waveform storage and coordinates conversion modules, and given specific design methodology and experimental results. Final papers for the virtual oscilloscope system testing and performance analysis, pre-design met requirements.The most important feature of this design is low cost. Easy access to the oscilloscope Y axis using the computer card, which has 16 spaces and the conversion accuracy of the sampling frequency of 44.1KHz, has resulted in the virtual oscilloscope can reach around 20K analog bandwidth, suitable for low frequency (0~20KHz) data collection application occasions.