Computer Simulations of a Megawatt-Class S-Band Coaxial Magnetron

The distinguishing feature of a coaxial magnetron design is the presence of a stabilizing cavity between an anode and an output waveguide, which is coupled to the cavity through a coupling slot. The cavity, which, in its turn, is coupled to alternate anode resonators through the appropriate number of coupling slots, operates in the azimuthally-uniform TE011mode. Such a design allows the anode system of a coaxial magnetron to consist of an increased number of anode resonators/vanes, as compared to the number of resonators/vanes employed in a conventional magnetron, where an output waveguide is coupled directly to an anode resonator through a single coupling slot. Combination of a stabilizing cavity and an increased number of anode resonators/vanes in a coaxial magnetron results in enhanced stability of its operating mode, increased anode current (number of magnetron spokes), reduced RF electric field between neighbor anode vanes, and a possibility to mechanically tune its operating frequency by varying length of the stabilizing cavity.