Patent ID: 6285252
Filing Date: 2001-09-04
Classification: H03F

Abstract:
A circuit for amplifying an input signal, comprising:a first amplifier having an input terminal to which the input signal is applied, whereby the first amplifier produces a distortion at its output terminal;a first attenuator having a first terminal coupled to the output terminal of the first amplifier;a phase-shifter having its input terminal coupled to a second terminal of the first attenuator thereby phase-shifting a signal from the first attenuator;a first combiner coupled to combine the input signal and the phase-shifted signal;a second amplifier having its input terminal coupled to an output terminal of the first combiner;a second combiner having its input terminals coupled respectively to the output terminals of the second amplifier and the first amplifier;a second attenuator coupled to attenuate an output signal from the second combiner; andan output amplifier having its input terminal coupled to an output terminal of the second attenuator,wherein a signal gain from the input terminal of the first amplifier to the input terminal of the output amplifier is zero.