Skyworks Solutions, Inc.
APPARATUS AND METHODS OF CALIBRATING A POWER AMPLIFIER SYSTEM TO COMPENSATE FOR ENVELOPE AMPLITUDE MISALIGNMENT

Abstract:

Apparatus and methods of calibrating a power amplifier system to compensate for envelope amplitude misalignment are provided. In certain configurations, a method of calibrating a power amplifier system includes generating a supply voltage of a power amplifier using an envelope tracker based on shaping a scaled envelope signal using shaping data generated at a target gain compression, controlling a variable gain of a variable gain amplifier based on a gain control level signal, changing the variable gain by adjusting the gain control level signal using a calibration module, monitoring an output of the power amplifier to determine an amount of variable gain at which a detected gain compression of the power amplifier corresponds to the target gain compression of the shaping data, and calibrating the power amplifier system to compensate for envelope amplitude misalignment based on the determined amount of variable gain.