Patent ID: 7366482

Claim:
A transmitter for outputting a transmitting signal while amplifying power of the transmitting signal, comprising: a variable gain amplification means for amplifying an input modulated signal based on the transmitting signal and controlling the gain based on a control signal; a power amplification means connected to the rear of the variable gain amplification means; a multiplier for multiplying the amplitude signal of the transmitting signal and the phase-modulated signal obtained by modulation of the phase signal of the transmitting signal to thereby apply amplitude modulation, wherein the power amplification means performs power amplification on the basis of the amplitude-modulated signal; and a power amplification control means for controlling a supply voltage of the power amplification means on the basis of the control signal, wherein: the power amplification means has a linear operating mode for amplifying power by using a linear operating region in input-output power characteristic of the power amplification means, and a saturation operating mode for amplifying power by using a saturation operating region in input-output power characteristic of the power amplification means; the control signal includes an operating mode set signal for setting the operating mode of the power amplification means; and the power amplification means operates in either operating mode on the basis of the operating mode set signal.