Patent ID: 9363852
Filing Date: 2016-06-07
CPC Classification: H05B

Claim Text:
1. A microwave heating apparatus comprising: a cavity arranged to receive a load; a microwave generator arranged to generate microwaves; a transmission line arranged to transmit the generated microwaves to the cavity; a sensing device arranged to measure electromagnetic field strengths configured to provide information about the phase and the amplitude of a reflection coefficient, the reflection coefficient being representative of the ratio between the amount of microwaves reflected back towards the microwave generator and the amount of microwaves transmitted in the transmission line from the microwave generator; and a control unit configured to detect whether the measured electromagnetic field strengths correspond to a reflection coefficient having a phase within a predetermined interval of phases and an amplitude within a predetermined interval of amplitudes, said predetermined intervals of phases and amplitudes corresponding to an operating region of the microwave generator, to measure a time during which the microwave generator is in the operating region, and to control feeding of microwaves to the cavity based on said detection and time measurement.