A 24-28 GHz Broadband Doherty Power Amplifier MMIC Based on GaN HEMT Technology for Millimeter-Wave Applications

This paper presents the design and simulation of a 4W Ka-band three-stage GaN microwave monolithic integrated circuit (MMIC) Doherty power amplifier (DPA) for millimeter wave applications using 0.15-μm gate-length GaN technology. The designed GaN MMIC DPA exhibits a saturated output power of 35.4 dBm with the gain of 24 dB in the frequency range 24~28 GHz. The simulated power added efficiency (PAE) better than 34.4% over the band, with a compact size of 4 mm × 2.1 mm. The output matching network in the designed MMIC DPA employs a compact topology that significantly reduces component count while maintaining optimal performance. The developed GaN power amplifier MMIC demonstrates high efficiency with a simplified architecture, exhibiting significant potential for millimeter-wave applications.