Patent ID: 8050637

Claim:
A polar modulation transmitter comprising: a polar modulation section that generates an amplitude signal from a baseband orthogonal signal generated based on transmission data; an amplitude modulation section that generates an amplitude modulation signal based on the amplitude signal; a phase modulation section that generates a phase modulation signal in a wireless frequency band based on a signal having at least a phase component of the baseband orthogonal signal; an amplifier that generates transmission data in the wireless frequency band by inputting the phase modulation signal as an input high frequency signal and inputting the amplitude modulation signal as a control signal; a detection section that calculates out of band power in two frequency bands of predetermined same detuning frequencies from the center frequency of the output signal of the amplifier; and a distortion compensation processing section that includes: a predistortion compensation section which stores distortion compensation processing data and executes predetermined distortion compensation processing based on the distortion compensation processing data for at least one of an input signal to the amplitude modulation section and an input signal to the phase modulation section using the amplitude signal as a reference signal: and a distortion compensation adjustment section which compensates a transient response characteristic of the output signal from the amplifier at the control voltage driving time based on the control signal, by executing a distortion adjustment to a signal output from the predistortion compensation section or the reference signal based on output of the detection section, wherein the predistortion distortion compensation section has a steady characteristic compensation circuit for linearizing the output signal of said amplifier in a steady state based on the output signal characteristic for a control voltage value in the steady state after a predetermined control voltage is input when a predetermined input high frequency signal amplitude is input.