| 摘要 |
Provided is a transmitter including a polar modulation circuit which adjusts a timing lag between an amplitude component and a phase component more accurately than a conventional art. The polar modulation circuit includes: an extraction section for extracting an amplitude component and a phase component from an input signal; a first processing section for performing a first signal process on the amplitude component; a second processing section for performing a second signal processing on the phase component; an amplifier for synthesizing an output of the first processing section and an output of the second processing section and amplifying the synthesized outputs; a first calculator for performing 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 for accumulating outputs of the first calculator; a second calculator for performing 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 for accumulating outputs of the second calculator; and a delay fluctuation detection/compensation section for obtaining a delay time of the amplitude component based on an amount of accumulation of the first accumulation section; obtaining a delay time of the phase component based on an amount of accumulation of the second accumulation section; detecting an amount of delay fluctuation by using the delay times; and adjusting timings of the amplitude component and the phase component. |
