Patent ID: 7196583

Claim:
A method of providing power control of a power amplifier used to amplify input signals modulated in accordance with a variable envelope modulation scheme, the power control being effective to control the output power of signals amplified by the power amplifier to be within a predetermined power control range, the method comprising: providing a power amplifier having a gain which reduces as the supply voltage to the power amplifier reduces, the change in gain over the voltage supply range of the power amplifier being at least the change in output power over the predetermined power control range; and during operation of said power amplifier to amplify input signals modulated in accordance with the variable envelope modulation scheme, controlling the output power of the power amplifier by regulation of the supply voltage to the power amplifier over a voltage control range, the power amplifier being arranged to provide that at each respective value of the supply voltage in the voltage control range the output power of the power amplifier is less than the saturation output power of the power amplifier.