Patent ID: 8477870

Claim:
A transmitter including a polar modulation circuit, wherein the polar modulation circuit comprises: an extraction section configured to extract an amplitude component and a phase component separately from an input signal; a first processing section configured to perform a first signal process which causes a delay on the amplitude component extracted by the first extraction section; a second processing section configured to perform a second signal processing which causes a delay on the phase component extracted by the first extraction section; an amplifier configured to synthesize an output of the first processing section and an output of the second processing section and amplify the synthesized outputs to generate an output signal; a first calculator configured to perform an exclusive OR logical operation between the amplitude component before being inputted to the first processing section and the amplitude component after having been inputted to the first processing section; a first accumulation section configured to accumulate outputs of the first calculator for a predetermined time period; a second calculator configured to perform an exclusive OR logical operation between the phase component before being inputted to the second processing section and the phase component after having been inputted to the second processing section; a second accumulation section configured to accumulate outputs of the second calculator for a predetermined time period; and a delay fluctuation detection/compensation section configured to: obtain a delay time of the amplitude component based on an amount of accumulation of the first accumulation section; obtain a delay time of the phase component based on an amount of accumulation of the second accumulation section; detect an amount of delay fluctuation by using the delay times; and adjust, in accordance with the amount of delay fluctuation, timings of the amplitude component and the phase component before being synthesized by the amplifier.