Equivalent circuit approach for the design of hole and slot bare anode block of magnetron

Abstract

Magnetron is a high-power microwave source with high demand among vacuum devices. Before the design, validating it with other methods gives confidence to the designer. An equivalent circuit analysis is developed for a 16 vanes hole and slot structure yielding the design parameters, hole radius, slot length, slot width, and anode height. This method is adopted to calculate the cavity resonant frequencies preferable over the field equations, simulation, and fabrication. From inductance and capacitance definition, dispersion equation of the anode block is derived for each mode. The equivalent circuit approach is validated with the simulation to verify consistency. The resonant frequency relative difference of these two methods is 1.46%. The inductance and capacitance changes are observed by parametric variation of these structure dimensions. Strapping causes the frequency shift from 3.1685 to 2.217 GHz, and change in the cavity resonant frequency with the strap depth and strap height are plotted.