System and method for analyzing a frequency response of an electromagnetic cooking device

A method for analyzing an extended frequency response of an electromagnetic cooking device comprising a resonant cavity comprising:

• controlling a plurality of RF signals comprising a first RF signal and a second RF signal within an operating range of the cooking device at a plurality of phase shifts between the first RF signal and the second RF signal;
• measuring a plurality of efficiencies of at least one reflection signal in the resonant cavity in response to a plurality of RF feeds generated from the RF signals for the plurality of phase shifts;
• modeling a partial frequency response of the resonant cavity with a numeric model comprising an efficiency function;
• calculating a plurality of interpolation parameters as coefficients for the efficiency function of the numeric model based on the plurality of measured efficiencies of the RF feeds in response to the plurality of phase shifts;
• estimating the extended frequency response of the resonant cavity for the operating range of the cooking device based on the numeric model with the plurality of interpolation parameters;
• and
• identifying at least one resonant mode as a localized maxima of the efficiency function from the measured efficiencies of the resonant cavity and calculated based on the numeric model with the plurality of interpolation parameters.