Patent ID: 6449465
Filing Date: 2002-09-10
Classification: H03F,H04L

Abstract:
An apparatus for the linear amplification of a radio frequency signal, the apparatus comprising:a modulating amplifier that is effective to modulate, in response to at least one control signal, and to amplify a radio frequency input signal to produce an output signal, wherein the modulating amplifier comprises: at least one input port coupled to receive the radio frequency input signal; an amplifier that amplifies the radio frequency input signal; an impedance modulator that modulates the radio frequency input signal in response to the at least one control signal; an output port; a signal coupler, coupled to the modulating amplifier, that is effective to sample a portion of the output signal to produce an attenuated output signal; and a feedback circuit, coupled to the signal coupler and the modulating amplifier, that is effective to determine a modulation error between a baseband input signal and the attenuated output signal and is effective to generate the at least one control signal to reduce the modulation error.