Design And Implementation Of Automatic Test System For Traveling Wave Tube Based On Labwindows/CVI

Traveling wave tube is a kind of microwave vacuum electronic device,which has been widely used in national defense fields,national fields and so on.In order to measure the whole tube characteristics of the traveling wave tube,the testers must not only master the use of microwave measuring instruments,but also master the microwave measurement technology of the traveling wave tube;in addition,because of the diversity,complexity,and batch testing of various technical indicators of the traveling wave tube,in response to the request,the task of setting up an automatic test system and implementing automated tests was put on the agenda.The research of this subject is the design and implementation of the automatic test system of characteristic parameters of TWT based on Labwindows/CVI.The main purpose of this project is to automate the testing of the characteristic parameters of TWT to solve the problems of low efficiency,low testing accuracy,influence of test results on human factors,and inability to fully preserve the process data of TWTs.This topic which takes the virtual instrument technology and traveling wave tube measurement technology as the theoretical basis,and based on the manual test of the characteristic parameters of the traveling wave tube,studies the design and implementation of the automatic test system of the traveling wave tube,mainly including the hardware platform design and software platform design of the automatic test system.The design of the hardware platform includes the research on the connection of computers,computers and instruments,microwave measurement instruments to be used for testing,and the construction of test system for different characteristic parameters of traveling wave tubes.The software platform design includes the study of computer operating systems,various bus communication protocols,program-controlled commands supported by the instrument,and development software that can be used to develop TWT automated test systems.In this paper,based on Labwindows/CVI and VISA library,an automatic test system for characteristic parameters of TWT is designed.This system sends SCPI commands to the test instrument through LAN bus to control the instrument to perform automatic test on the established test platform.The TWT automatic test system has simple and convenient operation,high test accuracy,and high test efficiency.It can quickly realize the test of the harmonic output ratio characteristics,third-order intermodulation ratio characteristics,noise power spectral density characteristics,noise coefficient characteristics,and group Delay wave characteristics,gain fluctuation characteristics,nonlinear phase shift characteristics,amplitude modulation-phase conversion coefficient characteristics,and gain compression characteristics.In addition,during the test process,the automatic test system will display the measurement curve and the result data on the test panel.After the test is completed,all the test information will be saved in the computer as an xml file,which is convenient for the tester to view and call.At the same time,a fast and accurate test method for harmonic output ratio is proposed,which accelerates the test speed and improves the test accuracy.Through the error analysis of the automatic test results and the manual test results of each traveling wave tube characteristic parameter,it is found that the error is within the working fluctuation range of the traveling wave tube and the effectiveness of the traveling wave tube automatic test system is verified.