DOHERTY AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To provide a Doherty amplifier in a simple configuration capable of obtaining linear amplification and a power combining operation nearly ideal by providing a gain compensation unit whose gain is changed in response to the level of a signal inputted to a pre-stage of a peak amplifier even when the same device is used for a carrier amplifier and the peak amplifier. SOLUTION: The Doherty amplifier includes: an input terminal; an input branch means for distributing a signal received from the input terminal to a first and a second paths; the carrier amplifier for amplifying the signal distributed to the first path by the input branch means; the peak amplifier 4 for amplifying only the signals of a prescribed level or over among the signals distributed to the second path by the input branch means; an output combining means for combining the output of the carrier amplifier with the output of the peak amplifier; and the gain compensation unit 6 provided to the pre-stage of the peak amplifier in the second path and changing the gain in response to the level of the received signal to correct the level of the distributed signals. COPYRIGHT: (C)2004,JPO&NCIPI