Theoretical And Experimental Research Of Relativistic Magnetron

After extensive review of the research into relativistic magnetron in the country and abroad, this paper explores the basic theories of magnetron and special physical problems of relativistic magnetron, proposes an obstacle, a highlight and a direction of the current development and application of relativistic magnetron: relatively low efficiency with typical value between 10% to 20%; frequency agile; miniaturization.With single particle model, fluid model and particle simulation tools, factors that affect electronics efficiency were analyzed, including electronics cyclotron rotation and rf-drift, Brillouin hub, space charge field and Larmor radius etc. Meanwhile the physical mechanism of the evolution of ordinary magnetron to relativistic magnetron was investigated. The conclusion is "strong" rf field plays a central role in the efficiency of relativistic magnetron. Based on this, the author proposes three ways to improve the efficiency of relativistic magnetron from different perspectives: â‘ lower the load Q value; â‘¡set an upper limit to work current; â‘¢ array of relativistic magnetron with high impedance. Particle in-cell indicates that in do so, the efficiency of relativistic magnetron can be up to 40%. Such a comprehensive research and multidimensional proposal find no parallel until now.After studying the mechanism of frequency tunable with couple cavities, this paper identifies mode competition and 0 mode component as the main barriers to limiting the frequency tunable range and the performance of relativistic magnetron, and proposes the relationship between mode competition, 0 mode component and rf field structure. Considering the experimental environment available, economize and practicability, this paper suggests a basic project on frequency agile relativistic magnetron, and perfect it with high frequency structure simulator (HFSS) according to the theory of rising magnetron, thus to design a S band frequency agile relativistic magnetron with 900MHz tunable range by adjusting dimension of syntonic cavities and open anode ports. According to the analyzed results, a frequency agile relativistic magnetron was designed by the numbers and successfully manufactured, whose performance in high load Q value and low load Q value was tested and whose output window breakdown phenomena in high power was analyzed. The research results prove that this frequency agile relativistic magnetron has 20% tunable range, exceed 1GW output power, whose output power and bandwidth product value is 40% higher than reported abroad.With engineering design method and finite element method, the magnetic circuit with radial polarization was calculated and studied. Considering previous experience, the author designed and manufactured a permanent magnet with high magnetic field fitted for the relativistic magnetron, whose average magnetic field in the interactive area reaches 0.57T and whose uniformity area...