Method and apparatus for digital envelope tracking with dynamically changing voltage levels for power amplifier

A device for digital envelope tracking with dynamically changing voltage levels, the device comprising:

• a power management unit for generating a set of supply voltages for a power amplifier based on a control signal, wherein the power management unit comprises:
• a voltage converter including a voltage regulator for generating the set of supply voltages based on a target voltage;
• and
• a setpoint generator for gradually increasing or decreasing the target voltage from a first level to a second level such that the set of supply voltages gradually increase or decrease from a first set of voltages to a second set of voltages in response to a gradual transition of the target voltage;
• a digital voltage level generator for determining voltage levels of the set of supply voltages and generating a set of digital voltage levels corresponding to the set of supply voltages, wherein the control signal is generated based on the voltage levels for the set of supply voltages;
• a control unit for determining characteristics of an input data stream and generate control signals for selecting one of the set of supply voltages and one of the set of digital voltage levels;
• and
• a signal pre-distortion unit for distorting the input data stream based on a digital voltage level selected among the set of digital voltage levels.