An oven includes a housing that defines a cavity therein, a radio wave generator coupled to the housing and configured to generate a radio wave to be transmitted to the cavity, a control unit electrically connected to the radio wave generator and configured to determine radio wave information related to an intensity, a phase, and a frequency of the radio wave to be generated by the radio wave generator, and a plurality of antennas electrically connected to the radio wave generator and configured to allow the radio wave to be radiated into the cavity. The plurality of antennas are spaced apart from one another, and the control unit is configured to determine the radio wave information for each of the plurality of antennas.