Predistortion of concurrent multi-band signal to compensate for PA non-linearity

A method of operation of a transmitter comprising:

• amplifying, via a power amplifier of the transmitter, a modulated concurrent multi-band signal to provide an amplified concurrent multi-band signal;
• and
• prior to amplifying, effecting predistortion of the modulated concurrent multi-band signal to compensate for a non-linearity of the power amplifier of the transmitter via a plurality of predistorters each configured to provide predistortion for a different one of a plurality of frequency bands of the modulated concurrent multi-band signal;
• where at least one predistorter of the plurality of predistorters provides predistortion for a corresponding frequency band of the plurality of frequency bands of the modulated concurrent multi-band signal based on carrier frequency information for the modulated concurrent multi-band signal;
• and
• where effecting predistortion of the modulated concurrent multi-band signal further comprises, for the at least one predistorter:
• receiving a plurality of baseband input signals that correspond to the plurality of frequency bands of the modulated concurrent multi-band signal;
• processing at least a subset of the plurality of baseband input signals based on one or more permanent basis functions of the predistorter to provide one or more permanent basis function output signals;
• processing at least a subset of the plurality of baseband input signals based on one or more temporary basis functions of the predistorter and the carrier frequency information to provide one or more temporary basis function output signals;
• and
• combining the one or more permanent basis function output signals and the one or more temporary basis function output signals to provide a predistorted output signal for the corresponding frequency band of the modulated concurrent multi-band signal for which the predistorter provides predistortion.

A method configuring a plurality of predistorters to effect predistortion of a concurrent multi-band signal to compensate for a non-linearity of a power amplifier in a transmitter, wherein configuring at least one predistorter of the plurality of predistorters comprises:

• determining one or more permanent basis functions for the predistorter that are not a function of carrier frequency information for the concurrent multi-band signal;
• wherein determining the one or more permanent basis functions comprises:
• identifying terms in an expansion of odd orders up to a maximum order of an expression for the concurrent multi-band signal that have center frequencies that are equal to a carrier frequency for one of a plurality of frequency bands of the concurrent multi-band signal for which the predistorter provides predistortion;
• and
• obtaining the one or more permanent basis functions from the terms identified as having center frequencies that are equal to the carrier frequency for the one of the plurality of frequency bands of the concurrent multi-band signal for which the predistorter provides predistortion;
• determining one or more temporary basis functions for the predistorter that are a function of the carrier frequency information for the concurrent multi-band signal;
• and
• configuring the predistorter with the one or more permanent basis functions and the one or more temporary basis functions.