Linear pre-amplifier for radio-frequency power amplifier

摘要

The invention concerns an amplifier comprising an input circuit (26) tuned on the frequency to be amplified and receiving in input the signal to be amplified, a first transistor (Q2) connected in common base, whereof the transmitter is coupled to an input circuit and whereof the collector supplies the amplifier output signal, and a feedback circuit returning on the base of said transistor a fraction of the output voltage. The feedback circuit comprises a capacitive bridge (Ca, Cb) and a second transistor (Q3). The input circuit can form part of a first stage of the amplifier or of a mixer.