The Research Of W Band Folded Waveguide Traveling Wave Tube

With the development of millimeter wave technology,there is an urgent need for the millimeter wave amplifier which can provide a certain bandwidth and power.The millimeter wave frequency is very high,relatively small bandwidth can provide a very wide absolute bandwidth,the satellite communication link in the attempt to use millimeter wave as carrier communication satellite and ground station at the same time,because of the high precision radar,are also used to millimeter wave.The millimeter wave band has three larger attenuation peaks in the atmosphere,the frequency is 60 GHz,120GHz and 180 GHz respectively.Because the attenuation in the atmosphere is as high as 15dB/km,the ground cannot be intercepted,and it can be used as the carrier of satellite relay.There are also four low attenuation atmospheric window,frequencies were 35 GHz,45GHz,94 GHz,140GHz,220 GHz,due to the narrow beam of millimeter wave,suitable for high speed data transmission from point to point,is the deployment of 5G networks will be regarded as the key technology of millimeter wave.W band is in the atmospheric window 94 GHz,it has a great application prospect in communication,radar electromagnetic countermeasure,and millimeter wave traveling wave tube is used for signal amplification is the ideal device,folded waveguide traveling wave tube is to solve the traditional traveling wave tube heat transfer performance is poor,difficult processing problem.At present,the competitive advantages of folded waveguide traveling wave tubes in millimeter wave devices are very large.In this paper,a W band folded waveguide traveling wave tube which work at 81GHz~86GHz,and output 100 W of pulse power and with a efficiency of 25% was proposed.The electronic optical system of the traveling wave tube is designed.We analyzed and summarized the electronic optical system including the design theory and method of electron gun,focusing system and collector,according to the specific requirements of the technology,with the initial value calculated approximate structure parameters,then the use of professional design software design process optimization simulation,electron optical system design of a work in the W band traveling wave tube.A folded waveguide slow wave line.The first theoretical analysis of the frequency characteristics of the slow wave structure of folded waveguide,using MATLAB according to the requirements of technical input and calculate structure parameters of the slow wave line preliminary,and use HFSS to analyze the impact of folded waveguide slow wave line parameters on high frequency characteristic,interaction with results calculated by TAU,finally in slow HFSS optimization wave structure,design calculation of the complete iterative TAU folded waveguide slow wave line.Input and output energy coupling device,attenuator.Based on the theory of equivalent circuit and pattern matching,the input and output energy coupling device and attenuator are analyzed.Finally,the optimized design of the structure is completed by using HFSS.