Design of the 80W Doherty power amplifier with offset lines

In this paper the design of a Doherty power amplifier is reported. The Doherty power amplifier is designed for high power applications for modern communication such as digital television system. In order to gain high efficiency and good linearity, the offset line technique is utilized. For verification, a 80W Doherty power amplifier is implemented by the computer simulation and circuit experiment. The measured results show the power added efficiency of 35.5% and the Adjacent Channel Power Ratio (ACPR) of -36dBc at the output power of 49dBm.

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