Transmitter with peak-tracking PAPR reduction and method therefor

摘要

A transmitter (20) includes a peak reduction section (30), a predistorter (98), and an amplifying section (102) biased by a variable bias signal generator (118). The peak reduction section (30) is controlled by a signal magnitude threshold (36) that defines maximum magnitudes for local peaks (32) of a reduced-peak communication signal (38). The bias signal generator (118) is controlled by a bias control signal (110). Both the signal magnitude threshold (36) and the bias control signal (110) are derived from a common reduced bandwidth (50) peak-tracking signal (42). The peak-tracking signal (42) is derived from an inflated-peak communication signal (26). The predistorter (98) applies distortion to the reduced-peak communication signal (38) that is configured, at least in part, by the bias control signal (110).

主权项

1. A transmitter configured to transmit a communication signal, said transmitter comprising:
a communication-signal source configured to produce an inflated-peak communication signal which exhibits a first bandwidth; an envelope tracking section which is responsive to said inflated-peak communication signal and configured to generate a peak-tracking signal which tracks magnitude peaks in said inflated-peak communication signal and exhibits a second bandwidth that is lower than said first bandwidth; a peak reduction section which converts said inflated-peak communication signal into a reduced-peak communication signal, said peak reduction section being responsive to a signal magnitude threshold which establishes maximum local peak values for said reduced-peak communication signal, said signal magnitude threshold being responsive to said peak-tracking signal, and said peak reduction section being configured to delay said inflated-peak communication signal into synchronism with said signal magnitude threshold, then combine said signal magnitude threshold with said delayed inflated-peak communication signal in order to form said reduced-peak communication signal; and an amplifying section responsive to said reduced-peak communication signal.