[Recipient of the 2026 Samsung Ho-Am Prize in Engineering for laying the groundwork for 6G transmitters through Doherty power amplifiers]
"Knowledge can be caught up with very quickly. In the end, what makes the difference in research is concentration, and for that, it is important to enjoy what you do.“
On September 8, POSTECH welcomed a world-renowned authority in wireless communications as a speaker for the POSTECH 40th Anniversary Lecture Series, a special lecture series commemorating the 40th anniversary of the university's founding. The speaker was Bumman Kim, Professor Emeritus of the Department of Electrical Engineering at POSTECH and recipient of the 2026 Samsung Ho-Am Prize in Engineering. The lecture was held at 3:30 p.m. in the main auditorium of the LG Cooperative Electronics Engineering Building and was attended by students, faculty, and staff.
Under the title "My Activities Toward the Power Amplifiers for Mobile Communication Systems," Professor Kim reflected on a research journey spanning nearly half a century and shared his outlook on the future of wireless communication technology. In particular, he described what led him to dedicate himself to power amplifier research and the process of perfecting Doherty amplifier technology, which has since become the mainstream approach in mobile communications. In doing so, he identified concentration as the defining quality of a good engineer, emphasizing that one must learn to enjoy one's work in order to concentrate.
Professor Kim also recounted the turning points of his research career. After moving from nuclear fusion and optoelectronic integrated circuits (OEICs) to semiconductor devices, he went on to achieve, during his time at Texas Instruments (TI) in the United States, the world's first millimeter-wave monolithic microwave integrated circuit (MMIC) and the power operation of heterojunction bipolar transistors (HBTs). HBTs are used today in the power amplifiers of most smartphones. Noting that "small discoveries accumulate to create major breakthroughs," Professor Kim encouraged the audience not to be afraid of venturing into unfamiliar fields. Members of the POSTECH community showed their passion as engineers by asking about the prospects of wireless communications research and seeking his advice on research directions.
The research underlying his lecture concerns radio-frequency (RF) power amplifiers, which enable signals in mobile communications to be transmitted over long distances with high accuracy. Professor Kim is recognized as "a pioneer who laid the foundation for next-generation wireless communication technology" for resolving the long-standing challenge of improving efficiency and accuracy at the same time through Doherty power amplifiers and envelope tracking technology, thereby dramatically enhancing the efficiency and performance of mobile communication transmitters. This technology is widely used today in the design of smartphone and base station transmitters and is regarded as key to the implementation of 6G mobile communication transmitters. In recognition of these contributions, the Ho-Am Foundation named Professor Kim the recipient of the 2026 Samsung Ho-Am Prize in Engineering.
These achievements are the fruit of more than three decades that Professor Kim has spent with POSTECH. He joined POSTECH in 1989, when it was a young university in only its third year. He went on to lead the Microwave Integrated Circuits Laboratory, growing alongside the university. In 2007, he was elevated to Fellow of the Institute of Electrical and Electronics Engineers (IEEE), a distinction conferred on the top 0.1% of IEEE members for outstanding research achievements, and in 2009 he was named the first POSTECH Fellow. The research to which he devoted half his life at a young university he boldly chose to join has now been recognized with a prestigious award of international standing.
The POSTECH 40th Anniversary Lecture Series is a commemorative lecture program marking the university's 40th anniversary that invites pathfinders who have forged their own paths in their respective fields. Following Professor David Baker, the 2024 Nobel Laureate in Chemistry; Seonghoon Woo, CEO of Amogy; and author Bernard Werber, Professor Emeritus Kim took the podium this year, continuing the series of meaningful lectures.