OUTPUT MATCHING DEVICE OF MICROWAVE DOHERTY AMPLIFIER

摘要

PURPOSE: An output matching device of a microwave Doherty amplifier is provided, which controls a matching to optimize an efficiency and a linearity according to a phase at a low output as maintaining its characteristics without changing the matching at a high output. CONSTITUTION: The microwave Doherty amplifier makes a Doherty operation by connecting quarter wave transformers(141,142) to a final output of a carrier amplifier(10) and a peaking amplifier(20) connected in parallel. A load matching circuit(121) achieving an RF output matching is connected to the output of the carrier amplifier and the peaking amplifier, and a phase tuning component is connected to a rear part of the load matching circuit. The phase tuning component connects an impedance line(131) to the rear part of the load matching circuit connected to the carrier amplifier and to the peaking amplifier. A phase delay line(151) is connected to a front part of the peaking amplifier to compensate a phase difference between the quarter wave transformer and the phase tuning component.