Noise Suppression and Precise Phase Control of a Commercial S-Band Magnetron

We demonstrate noise suppression and precise phase control of a commercial 2.45GHz magnetron aiming for wireless power transfer application. The impurity of the microwave spectrum was confirmed to be due to the switching frequency of 76kHz in the power supply. With the decoupling capacitor installed to the output of the high-voltage power-supply driving the magnetron, the spectral purity of the magnetron was significantly enhanced. And we achieved extreme precision in phase-control (peak-to-peak 0.3°) for the high-power (1 kW) microwave magnetron by applying the phase locking loop to the noise-suppressed magnetron system.