摘要 |
A communication device includes a transmitting circuit that includes a quadrature modulator; a receiving circuit that operates as a quadrature demodulator that, when being in a data non-transferring period, starts when power is switched on and ends when receiving operation starts, switches a local oscillator signal to a harmonic receiving signal, and detects the signal level of a harmonic included in a signal output from the transmitting circuit; a harmonic extracting circuit and a voltage control circuit that extract a harmonic from a modulated signal and adjust the harmonic so as to set the signal level less than or equal to a predetermined threshold. When being in the data non-transferring period, the transmitting circuit outputs a signal to the receiving circuit, the signal being generated by combining an amplified modulated signal with an under-adjustment signal. |