C-band Double-gap Output Cavity, Theoretical Analysis And Experimental Research

This dissertation mainly involves two parts, theory analysis and experiment investigations for double-gap output cavity. Firstly starting from all variables are taken as functions of the incident phase at the first gap by using the larger signal theory of one-dimension disc mode. Some basic laws of double-gap output cavity are analyzed, and energy equations for double gaps are derived. The latter are employed to program calculation to obtain some variable relation curves between unknown quantities, and thus the general energy relations of double-gap output cavity in which phase of electrical fields are inverse (i.e. it-modes) are studied in details. And then a practical double-gap output cavity of 21-modeshe split cavity is produced. To further understand the high-frequency character of it-modes, according to the matching conditions of electromagnetic fields, a cold dispersion relation is derived by solving Maxwell?equations for the fields in an equivalent periodic structure. The dispersion relation and field solutions are employed to numerically calculate eigenfrequencies and eigenfunctions for C-band the split cavity, and the distributing character of it-modes are discussed. In the last part of the dissertation, the C-band double-gap output cavity is designed by using the 2.5D, relativistic, fully electromagnetic, PlC code KARAT, and more optimizing the construct of output cavity. Then by modulating the different construct parameters, the cold tests are carried on, by which the low-Q output cavity of center frequency 3.74GHz and 7 of load Q is developed. Then the experiments of C-band HPM Oscillator are conducted by using the double-gap output cavity. Ultimately the high- power microwave of >300MW of peak power with 2Ons of bottom duration at 3.78GHz are obtained.