| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high efficiency radio transmitter for digital modulated waveforms by CDMA, WCDMA, and FDM having a large power difference between average power and peak power, whose occurrence probability is Rayleigh distributed. <P>SOLUTION: In the radio transmitter, a power supply control part receives information on modulation type of transmission RF signal from a host device, reads signal power distribution information and an efficiency characteristic of a high frequency amplifier for an applied modulation type from an internal memory on the basis of the received information, and controls an ET power supply by generating a controlling function so as to fix a voltage or widen a voltage selection range in a transmission signal power range of a low occurrence probability and increase the number of selectable voltages in a power range of a high occurrence probability instead. Thus, the radio transmitter maximizes efficiency of the high frequency amplifier. <P>COPYRIGHT: (C)2013,JPO&INPIT |
