To provide a communication device capable of reducing output power by suppressing reduction in power addition efficiency.

A base band signal generator 1 provides a modulation output to be transmitted. A fixed amplitude phase modulator 2 generates a fixed amplitude high frequency signal whose amplitude is fixed based on the modulation output. An amplitude signal generation means 7A generates an amplitude signal for reducing a modulation degree in pulse width modulation in an area whose modulation error is not more than a modulation error upper limit value. A pulse width modulator 8 generates a logical pulse signal having an ON period rate proportional to the amplitude of the amplitude signal and outputs the logical pulse signal to a switching means 5. The switching means 5 generates a burst signal by making the fixed amplitude high frequency signal intermittent by the logical pulse signal, amplifies the generated burst signal and outputs the amplified signal to a band-pass filter 6. The band-pass filter 6 filters the burst signal and outputs a transmission output.