METHOD AND APPARATUS FOR CALIBRATING AN ENVELOPE TRACKING SYSTEM

摘要

A method of calibrating an envelope tracking system for a supply voltage for a power amplifier module within a radio frequency (RF) transmitter module of a wireless communication unit. The method includes, within at least one signal processing module of the wireless communication unit: applying training signal having time-variant envelope to input of the RF transmitter module; receiving indication of instantaneous output signal value(s) for the power amplifier module in response to the training signal; and adjusting timing alignment between envelope tracking path of the envelope tracking system and transmit path of the RF transmitter module to align envelope tracking power amplifier module supply voltage to instantaneous envelope(s) of a waveform signal to be amplified by the power amplifier module, based at least partly on the received indication of the instantaneous output signal value(s) for the power amplifier module in response to the training signal.