Amplifier circuit and method

摘要

First and second amplifiers are respectively coupled to first and second lines, each having first and second portions. An auxiliary amplifier has an output coupled to an auxiliary line network which comprises: a first auxiliary line coupled between an auxiliary junction and a first intersection between the first and second portions of the first line; a second auxiliary line coupled between the auxiliary junction and a second intersection between the first and second portions of the second line; and a third auxiliary line for coupling the output of the auxiliary amplifier to the auxiliary junction. Each of the first and second lines have a higher-impedance portion and a lower-impedance portion whose lengths are substantially equal. Lengths of the respective first portions of the first and second lines sum to half a wavelength, and lengths of the respective second portions of the first and second lines sum to half a wavelength.

主权项

1. An amplifier circuit comprising:
a first amplifier configured to amplify a first input signal wherein an output of the first amplifier is coupled to an output node via a first transmission line, the first transmission line comprising a first portion having a first characteristic impedance and a first length, and a second portion having a second characteristic impedance and a second length; a second amplifier configured to amplify a second input signal, wherein an output of the second amplifier is coupled to the output node via a second transmission line, the second transmission line comprising a first portion having a first characteristic impedance and a first length, and a second portion having a second characteristic impedance and a second length; and an auxiliary amplifier configured to amplify a third input signal, wherein an output of the auxiliary amplifier is coupled to an auxiliary transmission line network comprising: a first auxiliary transmission line coupled between an auxiliary junction and a first intersection between the first and second portions of the first transmission line; a second auxiliary transmission line coupled between the auxiliary junction and a second intersection between the first and second portions of the second transmission line; and a third auxiliary transmission line for coupling the output of the auxiliary amplifier to the auxiliary junction; wherein for each of the first and second transmission lines the first and second portions consist of a higher-impedance portion and a lower-impedance portion whose lengths are substantially equal; and wherein the lengths of the respective first portions of the first and second transmission lines sum to half a wavelength, and the lengths of the respective second portions of the first and second transmission lines sum to half a wavelength.