The Research And Design Of Vlasov Quasi-optical Mode Converter Of Gyrotron

This paper analyzes the systematic design of nisov radiator rom the theoretical to the practical operation and conducted numerical calculation of Vlasov quasi-optical mode converter. The article first introduces the overall development of domestic and international quasi-optical mode converter, and then introduces various quasi-optical mode converter and ways to choose the conditions. The design principles and calculation methods of the quasi-optical mode conversion are given step by step. Finally, Matlab programming is used for numerical simulation.The entire system of quasi-optical mode converter is analyzed with geometrical optics and vector diffraction theory and methods of mathematical. First, it analyzes the radiators with the principles of geometric optics. At different modes, how to cut the waveguide, how to calculate the length of the incision and how to choose the type of radiator is presented. Design reflection equations and geometric parameters of the quasi-optical mode converter and analyze the relationship between the local coordinates and global coordinates. Then use the vector diffraction radiation to calculate the field and optimize its parameters repeatedly. The article derives the theory of vector diffraction theory, explains its physical meaning, and analysis Secularization vector equation of diffraction theory.Finally, through theoretical analysis, the article designed the Vlasov TE01 mode quasi-optical mode converte which working frequency is 94 GHZ and feed waveguide radius is 9mm. This quasi-optical mode selects a trapezoidal incision edge length of 81 mm and two parabolic mirrors. Calculated by programming optimization, a perfect Gaussian beam(TEM00 mode) is got in the output window, and the conversion efficiency is 76.42%. The algorithm and the cut surface of each reflection surface of the mirror and the current source equivalent is presented in detail. The feature in the calculation methods are as follows: Compared with the traditional area of the caliber of surface integral, used the equivalent current source method to divide the radiator into two surfaces(the cut surface of the radiator and the surface of the feed waveguide mouth), and calculate both surfaces of the equivalent current source, this method enables more accurate calculation.