The Influence Of Voltage Waveform And Magnetic Field Distribution On Relativistic Magnetron

The relativistic magnetron is an important member of the high-power microwave source family.Its structure is relatively simple,and its beam current quality is relatively low.The operating frequency ranges from L-band to X-band,and the peak output power reaches 100 MW to GW.Although relativistic magnetrons have reached a higher level of power output,in recent years,many studies have been conducted to improve the output characteristics of relativistic magnetrons,and some typical excitation techniques have been proposed,including anode excitation and cathode excitation.And magnetic excitation.Experiments have verified that the relevant excitation techniques are conducive to suppressing mode competition,reducing the start-up time and increasing the pulse width.Among them,magnetic excitation and anode excitation are periodic disturbances of the applied magnetic field and voltage along the angular direction.This paper mainly studies the influence of the working magnetic field and electric field along the axial aperiodic disturbance on the output characteristics of relativistic magnetrons.Theoretically,the working magnetic field in the relativistic magnetron is uniformly distributed,but the actual magnetic system due to the spatial structure makes it impossible to evenly distribute the applied working magnetic field in the working area of the relativistic magnetron.The role of the axial magnetic field is to bind the electrons emitted from the cathode,so that the electrons orbit in the angular direction in the interaction region to complete the wave-injection interaction process,that is,the process in which the electrons deliver their own energy to the high-frequency field.If the axial magnetic field distribution is not uniform,the angular velocity dispersion of electrons will be too large,and the interaction effect will be poor.The change in the voltage waveform affects the generation of the plasma and the movement of the electrons in the magnetron.The quality of the pulse voltage waveform mainly depends on the parameters in the pulse formation line.The actual pulse voltage waveform will fluctuate with time,and the voltage waveform and the theoretical value of the actual magnetron will be different due to the difference in point length,harmonic frequency,network bandpass,and upper frequency of the transmission line.There are different degrees of difference.This paper takes the A6 relativistic magnetron as the research model,firstly the basic theory of combing magnetrons,introduces the basic structure of the magnetron,the characteristics of the resonant cavity,the interaction principle,analyzes the movement process of the electron in the resonant cavity,and uses the BH curve.Find the workspace of the magnetron.Study the spatial distribution characteristics of the magnetic field applied to the relativistic magnetron,collect the experimental data of the magnetic field,import the data into the simulation program,and obtain the output result,compare it with the output characteristics under the uniform magnetic field,and use the simulation data to illustrate the experimental magnetic field conditions and Difference in output characteristics under uniform magnetic field conditions.Explain why the voltage waveform is indefinite during the experiment,and perform numerical simulation on the standard voltage waveform,obtain the output characteristics under the theoretical conditions,and then collect the irregular voltage waveform data with typical characteristics,and import the data into the simulation program.The corresponding simulation results are obtained through simulation calculation,the simulation results are analyzed,and then compared with the previous theoretical analysis results,the theoretical analysis is verified,and new conclusions are drawn.The final part of the article is the experimental verification,and the experimental results show that it is consistent with the results of the previous simulation analysis.