Choosing optimum method for the efficient design of a relativistic magnetron with diffraction output

The relativistic magnetron with diffraction output (MDO) is promising to be the most compact narrow band high power microwave source. In this paper, based on the theory of S-parameters, a method named “choosing optimum” is proposed for the efficient design of the MDO in any wave band. By means of S-parameters, the π-TE31 mode conversion efficiencies of an S band MDO are calculated and then verified by three-dimensional particle-in-cell simulations. In order to illustrate the advantage of the choosing optimum method, the S-parameters of another L-band MDO are computed in a wide range of structure parameters and two results are chosen with detail information. Compared with the conventional method, the choosing optimum method is not only a shortcut, but also a convenient and easy way for choosing the high efficient MDOs in any wave band to meet the needs of different applications.