Operation Modes Switchable Doherty Power Amplifier with Back-off Efficiency Reconfiguration

This paper presents a dual-band and wideband switchable Doherty power amplifier (DPA) with back-off efficiency reconfiguration. It can be operated in wideband mode and dual-band mode with higher back-off efficiency through switching the carrier and peaking amplifier roles directly. The phase relationship required for dual-mode operation is first given. Meanwhile, the efficiency reconfigurable feature is realized by utilizing the integrated compensating reactance (ICR) technology. To verify the proposed circuits, a back-off efficiency reconfigurable dual-mode Doherty power amplifier (DM-DPA) which can be operated in wideband mode from 3 GHz to 3.8 GHz and dual-band mode at 2.4 GHz and 4.4 GHz was designed and fabricated. The implemented efficiency reaches 35% and 40% for wideband mode and dual-band mode respectively at 6-dB back-off power. When excited by a 100-MHz long-term evolution-advanced modulated signal with 6.5-dB peak-to-average power ratio, the DM-DPA can achieve an average efficiency of more than 37.3% in both wideband and dual-band modes. To the best of authors' knowledge, this is the first kind of operation mode switchable DPA with back-off efficiency reconfiguration.