$S$ -Band Relativistic Magnetron Operation With Multichannel Radial Outputs of the Microwave Power

Abstract

The results of an experimental study of the S-band magnetron operation with a six-vane anode block and multichannel radial outputs for microwave power extraction are presented. The magnetron was driven by a linear induction accelerator (~350 kV, ~2.5 kA, and 150 ns). In the case of three outputs for microwave power extraction and another three outputs connected to waveguides short circuited by movable plungers for adjusting the magnetron resonance, frequency-stable generation of the microwaves radiation with a total power of 570 MW from these three outputs was demonstrated. This power was equal to the power obtained when the same magnetron with one output was operated with high efficiency ( $\geq 40$ %). In addition, it was shown that the distribution of the generated microwave power between the three outputs allows wedge insulators to be used in the waveguides vacuum–air interface without electrical breakdown. Finally, microwave radiation, extracted in free space by a cluster of horn antennas connected at the output of the waveguides, was coherently added to each other at the desired distance with a three times larger microwave power density than in the case of 570-MW single output magnetron operation.