Research On Millimeter-wave Sheet Beam Extended Interaction Oscillator

Millimeter wave usually refers to the electromagnetic wave with a wavelength between 1-10 mm and a working frequency between 30 GHz and 300 GHz.Millimeter wave technology has a great application in national defense,artificial detection,5G communication,driverless cars and other aspects.The millimeter wave oscillator is an important part of the millimeter wave technology and has great research value.Extended interaction klystron and extended interaction oscillator are called extended interaction devices.Among them Extended interaction klystron(EIK)is a compact amplifier which has been used as important source of high power millimeter-wave vacuum device.ElO plays an important role in scientific,commercial and military applications such as communication,radars,transmitters,atmospheric sensing and near object analysis.The interaction cavity of EIO is shorted slow wave structure which takes advantage of the merits of traveling wave tube(TWT)and klystron.The common extended interaction oscillators are cylindrical EIO and sheet beam EIO.The difference between cylindrical and sheet beam injection lies in their electron channels.Among them,the traditional cylindrical EIO is difficult to produce high power because of the small size and large current density in the resonant cavity.Sheet Beam injection of EIO can significantly reduce the current density of the beam,thus reducing the free space charge effect of the beam.Compared with circular injection EIO,it can carry more current,thus enhancing the beam power and achieving high output power.For example,researchers at CIP have designed a high frequency CW tunable EIO with a working frequency of 264 GHz and a power output of 1W.Compared with sheet beam EIO,ribbon EIO has better heat dissipation effect and more power capacity.In this thesis,we explore the millimeter-wave sheet beam extended interaction oscillator.Design the high-frequency structure of the Ka-band and discuss the relationship between the number of gaps and the characteristic impedance and output power.Based on the fact that the electronic channel and the output port are unchanged,the influences of the parameters of the coupling cavity and the interaction gap and the coupling port on the resonance frequency,the characteristic impedance and the field strength distribution are expanded,and the parameters of the coupling cavity and the interaction gap are changed.The effect on the dispersion curve.Finally,the design of the electronic injection into the 1mm × 4mm electronic channel under the electronic injection 0.8mm × 3.2mm,at the working voltage of 15.5kV,operating current 4A,operating frequency of 33.57 GHz,finally reached the output power of 14.9 kW,Ka-band Sheet Beam extended interaction oscillator with 24% electronic efficiency...