Study On Millimeter Wave Dual-Band TWT

Millimeter-wave dual-band TWT is a kind of adjustable frequency traveling wave tube,it is one of the special vacuum electronic devices which can make aslow wave circuit working at two frequencies bands.The operating bandwidth and output power of this kind of TWT need to be as possible.It has significance in the development of radar and communication systems,not only can effectivelyreduce the radar transmitter system size,weight and cost for the rapid development of mobile system and provide lightweight,compact transmitter solutions,but also can promote the dual-band radar system research.Therefore,it has important academic and practical value.So far,the research of millimeter-wave dual-band TWT is just limited to some of the traveling wave tube research institute company,but research in this area is blank in China.This paper is about a kind of sloe-wave structure of dual-band helix TWT working at Ka/Q band(29~31 GHz and 43.5~45.5 GHz).In this paper,the high frequency characteristics,beam-wave interaction and the structure of dual-band TWT are analyzed,and the structure parameters are optimized by high frequency simulation software.It is shown that the optimized dual-band space helix TWT can meet the design requirements well.The main work and innovations of this dissertation are shown as follows:1.Based on the existing slow-wave structure with weak dispersion characteristics,the high-frequency characteristics of the slow-wave structure which is suitable for Ka /Q dual-band TWT is analyzed and optimized by using the three dimensional electromagnetic simulation software and simulated by optimizing the design or improving the structure.2.The structure parameters and operating parameters are designed by ORION code.According to these parameters,beam-wave interaction simulation of the Ka/Q dual-band helix TWT are calculated by CST software.The beam-wave interaction simulation predicts a minimum output power of 199/191 W,minimum electronic efficiency 15.1%/12.5%,and maximum gain of 49.9/49.8 dB,respectively,for Ka band(29~31 GHz)and Q band(43.5~45.5 GHz).3.According to the beam voltage and current requirement of the Ka/Q dual-band helix TWT,a dual-anode electron gun suitable for.This TWT is designed by ORIONcode.