Permanent Magnet Packaging Tunable Relative Research Of Magnetron

After extensive review of the research into relativistic magnetron (RM) in the country and abroad, this paper explores the basic theories of magnetron and special physical problems of relativistic magnetron. After analyzing the Hull cutoff condition and the B-H condition and plotting the dispersive curve of2typical RM resonant systems:the A6system and the rising-sun system with10caves, compare this2kinds of resonant systems and the conclusion is that the rising-sun system with10caves can work in a larger B-H region and have less mode competition.Based on the resources and research results of our laboratory, designed the first permanent magnet packaging Tunable-RM over the world, and demonstrated the feasibility of the design program. Early experiment researches of the permanent magnet packaging Tunable-RM has been finished.A10caves rising-sun anode,which’s smaller caves is tunable, has been used to verify the tunable properties of the permanent magnet packaging RM, the output microwave frequency range of the permanent magnet packaging RM was2.73GHz-2.88GHz while the depth of the small cavity was10mm-13mm. The permanent magnet packaging RM output more than1GW microwave power in S-band and the efficiency is about13%. lOHz repeat pulse experiment of the permanent magnet packaging RM has also been finished, and we get more than500MW microwave power and the efficiency is more than8%.All of those experiments used the old permanent magnet with the peak value of5940Gs.Explores the effects of axial non-uniform magnetic field on RM, which is ineluctable in practical. Work out the Spatial distribution of magnetic field based on the B-field on Z-axial, and aware of that the Br is enough small to ignore. Analyze the trajectory of a single electron with axial non-uniform magnetic field; the conclusion is that the axial non-uniform magnetic field brings more mode competition to RM and the3D PIC simulation work out the same result, RM can work successfully when the degree of magnetic field non-uniformity is less than6.9%. At the same time, the simulation result shows that when the degree of magnetic file non-uniformity is between4%and6%,the time when RM starts to work smoothly is shorter. The theoretical analysis and the3D PIC simulation results confirmed that longer cathode rod can effectively suppress the axial drift of electronics, thereby reducing the mode competition caused by the axial non-uniformity magnetic field. And the output power and efficiency has increased by11%when the longer cathode rod is been used.The experiment researches of the first permanent magnet packaging Tunable-RM over the world have been finished. In the experiment of the permanent magnet packaging Tunable-RM,which with the peak magnetic field value of4993Gs, we get more than500MW output microwave power in the operating bandwidth, which is300MHz in S-band, center frequency is2.77GHz and the efficiency is6%-16%.