A communication device changes an applied voltage output from a voltage circuit, and allows a capacitance measuring device to measure the respective capacitance values of a variable capacitance element before and after a change in the applied voltage. The communication device calculates a voltage correction value for correcting an initial variation of the capacitance value of the variable capacitance element using the respective capacitance values of the variable capacitance element before and after the change in the applied voltage, and respective applied voltage values before and after the change, and a correction voltage for canceling the initial variation in the capacitance value of the variable capacitance element, and outputs the correction voltage from the voltage circuit.