Patent ID: 8185065

Claim:
A transmitting unit which reduces peak to average power ratio (PAPR) for a communication signal, said transmitting unit comprising: a modulator configured to form a communication signal having signal components confined within a bandwidth; a clipping section coupled to said modulator, said clipping section being configured to generate a threshold-responsive signal having distortion within said bandwidth and outside said bandwidth; a notching filter coupled to said clipping section, said notching filter being configured to notch a frequency spectrum of said threshold-responsive signal to generate a notched signal, wherein said frequency spectrum is notched adjacent to said bandwidth; an upconverter coupled to said notching filter, said upconverter being configured to frequency shift said notched signal into an RF signal in which said bandwidth has been frequency shifted to an RF bandwidth, said distortion within said bandwidth has been frequency shifted to said RF bandwidth, and said distortion outside said bandwidth has been frequency shifted outside said RF bandwidth; an RF amplifier coupled to said upconverter and configured to form an amplified RF signal from said RF signal; and a bandpass filter coupled to said RF amplifier and configured to filter said amplified RF signal to attenuate said distortion outside said RF bandwidth.