Patent ID: 6525603
Filing Date: 2003-02-25
Classification: H03F

Abstract:
A method of reducing distortion in a feedforward amplifier output signal, the method comprising:receiving an input signal; modulating the input signal with a modulation source signal; delivering the modulated input signal to a main amplifier to produce an output; extracting a sample of the output of the main amplifier; subtracting a sample of the input signal from the extracted sample of the output of the main amplifier thereby producing an error signal; detecting the presence of the modulation source signal in the output of the feedforward amplifier; and adaptively modulating and amplifying the error signal, and combining the modulated and amplified error signal with the main amplifier output so as to minimize the presence of the modulation source signal in the output of the feedforward amplifier; wherein the input signal is modulated to create a single additional sideband with a carrier signal maintained.