Multi-Level Chireix Outphasing Gan Mmic Pa

This paper presents the design and performance of a 9.7GHz GaN MMIC Chireix outphasing PA with discrete supply modulation. This architecture is referred to as Multi-Level Chireix Outphasing (ML-CO). The internal PAs include class-F harmonic terminations, while the Chireix combiner provides the fundamental frequency load modulation. A peak output power of 37dBm (5W) is achieved, while a peak eta(tot) of 60.2% is reached at 35.7 dBm. The average total efficiency calculated for a 6 dB PAR QPSK signal is 48.1 %, a 15.5 point improvement over the constant supply case.