This chapter contains new simulation results concerning the physical foundations of how microwave tubes operate based on Cherenkov’s mechanism of radiation (interaction with slow electromagnetic wave) and some experimental results connected with improving the output characteristics of the magnetrons (a mm band surface wave magnetron and a magnetron with two RF outputs of energy), as well as results of computer modeling of a 320-GHz band traveling wave tube (TWT). The results of analytical calculations and computer modeling, a phase bunching process in the mm band surface wave magnetron, are considered. It is shown that the process of phase focusing has two features associated with a concentration of RF wave energy close to the vanes of an anode block and higher electron hub of a space charge as compared to the classical magnetrons. The features and examples of practical application of the magnetron with two RF outputs of energy are presented. It is shown that the main advantage of the magnetrons is its extended functionalities (for example, possibility of frequency tuning including electronic tuning of a frequency from a pulse to pulse). The presented materials will be of interest not only for starting researchers but also for those who have microwave tube experience.
Part of the book: Electromagnetic Fields and Waves