Patent attributes
An amplifier circuit includes an RF amplifier that is configured to amplify an RF signal between a first terminal and a second terminal across an RF frequency range. The amplifier circuit includes a multi-stage impedance matching network having a broadband impedance transformer, a phase shifter, and a high-pass impedance transformer connected in series with one another between a first port of the amplifier circuit and the first terminal. The broadband impedance transformer provides impedance transformation in the RF frequency range. The phase shifter shifts a phase output port reflection coefficient in a second order harmonic frequency range that overlaps with a second order harmonic of the fundamental RF frequency. The high-pass impedance transformer transmits an RF signal in the RF frequency range while providing impedance transformation in the RF frequency range and transmits RF signals in the second order harmonic frequency range with low impedance.
