Patent ID: 7248642

Claim:
A method for reducing spurious emissions in an amplified signal, comprising the steps of: (a) receiving an input signal; and (b) applying frequency-dependent phase pre-distortion to the input signal to generate a pre-distorted output signal, wherein the frequency-dependent phase pre-distortion is based on at least one corresponding phase difference between at least one pair of critical frequencies, such that, when the pre-distorted output signal is applied to an amplifier to generate the amplified signal, the frequency-dependent phase pre-distortion reduces spurious emissions in the amplified signal, wherein step (b) comprises the steps of: (1) generating a main output signal from the input signal; (2) generating one or more frequency-dependent phase pre-distortion signals from the input signal; and (3) advancing or delaying each frequency-dependent phase pre-distortion signal relative to the main output signal; and (4) combining each advanced or delayed frequency-dependent phase pre-distortion signal with the main output signal to generate the pre-distorted output signal.