Experimental observation of two microwave radiation mechanisms with widely separated frequencies during the output pulse of a high-voltage virtual cathode oscillator

Abstract

Results from two 4 MV, 100 kA coaxial magnetically insulated transmission line virtual cathode oscillator experiments are presented. In both experiments, two distinct microwave pulses with vastly different frequencies were generated during the beam current pulse. The first, lower frequency pulse was found to be produced by an electron reflexing process, while the second, higher frequency pulse was due to the virtual cathode oscillation mechanism.

Time-frequency analysis of virtual cathode oscillator

“…Virtual cathode oscillator is one of the promising devices being developed as high power microwave sources [3]. Research efforts on virtual cathode oscillator have been concentrated on efficiency improvement and oscillation frequency control [4][5][6][7][8].…”