CPC H03F 1/0288 (2013.01) [H03F 1/565 (2013.01); H03F 3/211 (2013.01); H03F 2200/222 (2013.01); H03F 2200/387 (2013.01); H03F 2200/451 (2013.01)] | 20 Claims |
1. An inverted Doherty amplifier comprising:
a main amplifier in a first circuit branch;
a peaking amplifier in a second circuit branch;
a combining node located where a first portion of the first circuit branch after the main amplifier connects with a second portion of the second circuit branch after the peaking amplifier;
a first impedance-matching component connected in the first portion of the first circuit branch between the main amplifier and the combining node, the first impedance-matching component comprising an output impedance of Rcomb; and
an impedance inverter connected in the second portion of the second circuit branch between the peaking amplifier and the combining node, the impedance inverter comprising an impedance value of Rcomb/α, wherein:
α is an asymmetry factor for the inverted Doherty amplifier,
the asymmetry factor is a ratio of a maximum power output by the peaking amplifier to a maximum power output by the main amplifier, and
the impedance inverter adds a phase delay of approximately 270 degrees.
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