| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an envelope tracking radio-frequency amplifier that can suppress gain degradation even if an envelope of an input modulation signal has a wide dynamic range. <P>SOLUTION: A modulation power supply circuit 100 comprises: a modulation power supply 120 which adjusts an output voltage according to a modulation power supply control signal corresponding to an envelope signal; a first radio-frequency device 140 that operates optimally in a first voltage region where the output voltage is high; a second radio-frequency device 150 that operates optimally in a second voltage region where the output voltage is lower than the first voltage region; an input RF switch 160 and an output RF switch 170 that switch one of channels and output signals of the first radio-frequency device 140 or the second radio-frequency device 150; a signal generation part 112 that generates a switching signal capable of controlling the input RF switch 160 and the output RF switch 170. <P>COPYRIGHT: (C)2012,JPO&INPIT |
