Recently, Fang Xiaohu's research team from the National Demonstrative Microelectronics College, part of the College of Engineering at the Southern University of Science and Technology, has achieved notable advancements in the design of broadband radio frequency (RF) and millimeter-wave integrated circuits. Their work encompasses both theoretical innovation and practical engineering applications, with a particular focus on RF front-end modules, including high-efficiency power amplifiers, millimeter-wave RF switches, and ultra-wideband low-noise amplifiers.

Among their key accomplishments, the linear millimeter-wave GaN monolithic integrated Doherty power amplifier stands out. This device leverages complex-to-real impedance modulation technology, delivering an Adjacent Channel Power Ratio (ACPR) of -34dB and an Error Vector Magnitude (EVM) of 2.8% under a 400MHz 5G NR FR2 64QAM signal. Additionally, the broadband switchless Class-G amplifier achieves impressive saturation efficiencies ranging from 47.8% to 57.7%, along with back-off efficiencies between 39.2% and 51.2% within the 1-3GHz frequency range.

Another highlight is the high-efficiency C-band Class-F power amplifier, which incorporates a multifunctional bias network and a harmonic isolation LC resonator, resulting in an energy efficiency ratio exceeding 70%. Furthermore, the broadband millimeter-wave power amplifier successfully attains broadband matching across the 24.5-29.5GHz frequency band by effectively compensating for transistor parasitic capacitance.

These significant findings have been published in prestigious journals, including the IEEE Transactions on Microwave Theory and Techniques. Some of the research projects have also received financial support from esteemed institutions, such as the National Natural Science Foundation of China.