Far-field measurement of microwave mode radiated by an axial feedback vircator

Far-field measurement is carried out for the radiation patterns from the opening of the vircator and the opening of the TM01-TE11 converter connected with the vircator, with the distance being 1.00 m between the openings of the receiving horn and that of the microwave radiation. The results show that the main modes of the radiation are the TM01 and TE11, respectively. This confirms the theoretical expectation of the TM01 main mode for the microwave generated by an axial feedback vircator with experimentally cylindrical symmetry. Modes analysis shows that the radiated microwave has its main mode of the TM01 with its mode-purity of about 90%, and that the radiation power exceeds 300 MW, with the power of the TE11 mode being approximately 5% of that of the TM01 mode, and the total power of th