Research And Design Of High Frequency Scalar Network Analyzer With USB

Scalar network analyzer is a kind of intelligent instrument based on frequency sweep test technology that used to measure the amplitude-frequent cy characteristic of linear system.Network analyzer adopt these new technology such as frequency synthesis,sampling technique,broad-band sweeping and computer-assisted testing.This paper propose and design a kind of high frequency scalar network analyzer with USB.Firstly,discuss the intention and meaning of this research of network analyzer,introduce the characteristic of usb technology and the process of development.Then provide the base of network analyzer and the method,summarize the overall project of hardware,put forward the scheme of PC software.Lastly ,this paper give the debug result of an example and suggestion for the future work .In the design of hardware,frequency sweep signal is based on DDS+PLL.By the control the singlechip C8051F060,AD9852,the DDS chip, can achieve stepped frequency signal.With amplifying and detector circuits ,the instrument can achieve the measurement and receiving of amplitude frequency characteristic result.By means of PDIUSBD12 finish the USB1.1 protocol conversion, communicate with USB interface of PC,the instrument give the measurement resul of amplitude-frequency characteristic in LCD of PC.In the design of software,this paper stress the USB system drive archecture and the idea of firmware programming.Based on WDM drive programming thinking,give an example of USB device drive.Under the environment of Visual C++ 6.0, adopt the idea of object-orientation ,modular design and multithreading to finish the development of user application ,including the function of operation interface,USB device attachment,wave display, parameter read/write, document printing and saving .