摘要 |
A Doherty amplifier includes an impedance transformer located between a load and a signal combining point of a carrier amplifier and a peak amplifier. The impedance transformer subjects, at frequencies including a fundamental frequency and at least a second harmonic frequency thereof, an impedance Zo of the load to impedance transformation into a value lower than Zo, for example, (½)×Zo, over a wide band or a plurality of frequency bands.
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