Patent ID: 6504428
Filing Date: 2003-01-07
Classification: H03F

Abstract:
A RF power amplifier arrangement comprising:an RF input port to which an RF input signal is applied; an RF output port from which an RF output signal is derived; an RF carrier cancellation loop coupled between said RF input port and said RF output port and including an RF amplifier stage that is operative to provide a first amplified RF output, said RF amplifying stage including first and second RF signal processing paths containing first and second matched RF power amplifiers coupled in circuit with one another in such a manner that said second matched amplifier is pre-distorted by the output of said first matched amplifier which is driven by essentially the same RF signals driving said second matched amplifier, said first and second RF signal processing paths being differentially combined to produce a composite RF output in which RF carrier components constructively combine and distortion introduced by said matched RF power amplifiers destructively combine; a feed-forward amplifier loop coupled to said RF carrier cancellation loop and being operative to provide a second amplified RF output containing distortion introduced by said RF amplifier stage but effectively excluding said RF input signal; and an output signal combiner coupled to receive said first and second amplified RF outputs of said RF carrier cancellation loop and said feed-forward amplifier loop, respectively, and being operative to produce a composite RF output signal, in which distortion introduced by said RF amplifier stage is reduced.