Patent ID: 7392023
Filing Date: 2008-06-24
Classification: H03G,H04W

Abstract:
1. A transmitter comprising: a power amplifier having an amplifier power-supply input and an output for supplying a transmission signal with an output power, a power supply having power supply outputs for supplying a first power supply voltage and a second power supply voltage, a switching circuit arranged between the power supply outputs and the amplifier power-supply input, and a controller having an input for receiving a power change command to control: (i) the switching circuit to supply the first power supply voltage to the amplifier power-supply input, and the power supply to vary a level of the second power supply voltage to be lower than a level of the first power supply voltage if the power change command indicates that the output power has to decrease and to be higher than the level of the first power supply voltage if the power change command indicates that the output power has to increase, and (ii) the switching circuit to supply the second power supply voltage to the amplifier power-supply input; wherein the power supply supplies a third power supply voltage, the controller controls (i) the level of the second power supply voltage to above a level of the first power supply voltage, and a level of the third power supply voltage to below the level of the first power supply voltage, (ii) the switching circuit to supply either the second power supply voltage or the third power supply voltage to the amplifier power-supply input, depending on whether the output power has to increase or decrease, respectively.