Alternative concepts for wideband Doherty power amplifiers

Heidebrecht, Eduard; Negra, Renato (Thesis advisor); Reynaert, Patrick (Thesis advisor)

Aachen : RWTH Aachen University (2023)
Dissertation / PhD Thesis

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2023


As we increasingly develop on technologies such as autonomous driving, Industry 4.0, and cloud computing, the need for reliable and high-speedwireless communication is more crucial than ever. However, increasing the frequency bandwidths and centre frequencies of wireless communication systems to achieve higher data rates leads to physical limitations on the receive input power of RF receivers. To overcome these limitations, the next generation of wireless communication will combine multiple antennas to an active beamforming transceiver system. This is technically challenging, particularly for the power amplifiers, which need to provide high bandwidth, be small in size, and perform energy-efficient amplification for complex modulated signals. In this thesis, the author explores the use of the Doherty power amplifier (DPA) as a potential solution to these challenges. While DPAs have some limitations in terms of bandwidth and area consumption, they are promising to increase the overall energy efficiency of the transceiver system. The author proposes alternative architectures, which promise to provide higher frequency bandwidth and high integrability. Through the development of three prototypes using complementary metal-oxide- semiconductor (CMOS), gallium nitride (GaN) monolithic microwave integrated circuit (MMIC), and hybrid design technologies, the author demonstrates the potential of these wideband designs with 5 dB to 10 dB output power backoff (OBO) while also reducing the area consumed in all used technologies. The proposed architecture also leads to the smallest transmission line based DPA combiners ever reported, which paves the way for energy-efficient, high power amplifiers with highest integration capability.


  • Chair of High Frequency Electronics [618510]