Patent ID: 7915969
Filing Date: 2011-03-29
Classification: H03F,H04L

Abstract:
1. A polar modulating circuit comprising: a polar coordinate converting portion which produces an amplitude signal and a phase signal from a baseband quadrature signal that is produced from transmission data; a distortion compensation processing portion which includes a memory portion for storing predistortion distortion compensating process data for a predetermined phase correcting process and outputting an phase correction signal for correcting the phase signal, and a phase compensating circuit for phase compensation; an amplitude modulating portion which produces an amplitude-modulated signal based on the amplitude signal; a phase modulating portion which produces a phase-modulated signal in a radio-frequency band based on a phase signal corrected by using the phase correction signal output from the memory portion; and an amplifying portion into which the phase-modulated signal is input as an input high-frequency signal and the amplitude-modulated signal is input as a control signal, thereby producing transmission data in the radio-frequency band, wherein the phase compensating circuit performs the phase compensation by adjusting amplitude of an address designation signal when the phase correction signal is output from the memory or adjusting an amplitude of the phase-modulated signal input to the amplifying portion as the input high-frequency signal.