| 摘要 |
PROBLEM TO BE SOLVED: To provide an amplifier which responds to a limit of the response speed and a nonlinear characteristic of a device performing control of a drain voltage, and generates an envelope tracking signal in a form close to an envelope of an original transmission signal, to provide an amplifier control method, and to provide a transmitter. SOLUTION: An envelope detector 22 detects an envelope of a transmission signal. A differentiator 11 calculates a differential component by differentiating the envelope by time. A filter processor 12 performs filter processing to the differential component. An integrator 13 generates an envelope tracking signal by integrating each differential component subjected to the filter processing with respect to time. A drain voltage controller 25 controls a drain voltage based on the envelope tracking signal. An amplifying unit 28 amplifies a transmission signal according to the drain voltage controlled by the drain voltage controller 25. COPYRIGHT: (C)2011,JPO&INPIT |
