Patent ID: 8520767

Claim:
A transmission circuit using polar modulation, comprising: a signal generation section operable to process an input signal and generate an amplitude signal representing an amplitude component and a phase signal representing a phase component; a delay adjustment section operable to calculate a difference between a signal delay amount in an amplitude path and a signal delay amount in a phase path based on the amplitude signal, the phase signal, and a feedback signal and adjust, in accordance with the difference, one or both of the signal delay amount in the amplitude signal and the signal delay amount in the phase signal; a phase modulation section operable to modulate a predetermined carrier signal by an adjusted phase signal adjusted by the delay adjustment section and generate a phase modulation signal; a regulator operable to output a voltage control signal in accordance with a magnitude of the adjusted amplitude signal adjusted by the delay adjustment section; an amplitude modulation section operable to modulate the phase modulation signal by the voltage control signal and output the modulated signal to an antenna as a transmission signal; and a feedback signal generation section operable to, by receiving a same phase modulation signal and a same voltage control signal as those received by the amplitude modulation section, modulate the received phase modulation signal by the received voltage control signal and feed back the modulated signal to the delay adjustment section as the feedback signal, wherein the feedback signal generation section has a circuit scale which is smaller than a circuit scale of the amplitude modulation section.