The Design And Implementation Of High-accuracy Virtual Frequency Instrument Based On USB2.0

Industrial control, information transmission and processing as well as modern digitization technology can't act normally without time-frequency technology and time-frequency measure. That the traditional frequency instrument, however, whose function is realized through hardware circuit or solidified software, causes high cost of the traditional products and its exploitation expense, as well as slow updating speed.Comparing to the traditional frequency instrument, the frequency instrument based on the virtual instrument technology has the advantages of low cost, flexibility and convenience, which has broad practical prospect and market that the former is unapproachable. In the virtual reality system, the data analysis and display are accomplished by the PC machine software completely. So it can compose a measure instrument by connecting the data collection hardware with PC through a special connection so long as provided a data collection hardware.This article designs a high accuracy virtual frequency instrument based on USB2.0 by combining the virtual instrument technology, the USB2.0 connection and the frequency measurement algorithm having the key function in the time frequency technology. This article proposes the solution and realization procedure of this topic, and gives a more detailed elaboration of the related technology, for example the high accuracy frequency measurement algorithm, the FPGA logic succession design, the device driver, the firmware code, the application program and so on. Meanwhile this article has realized the system design by using the corresponding design tools, and has provided the system structural model and design point.At last, the thesis summarizes all work finished that is related to this project, and prospects the evolution of this project.