K. J. Ray Liu

Kuo-Juey Ray Liu (; born February 11, 1961 is a Taiwanese-American electrical engineer and entrepreneur. He was the founder, chairman, chief technology officer (CTO), and chief executive officer (CEO) of Origin Wireless, Inc., an artificial intelligence analytics company pioneering wireless sensing and indoor tracking technology, which was acquired by ADT, Inc. in 2026. He was also the founder and president of Odyssey Technology, a company which developed the earliest Internet-based digital surveillance system.

Liu was the Distinguished University Professor at the University of Maryland, College Park, where he retired in 2021. In 2022, he was the president and CEO of the Institute of Electrical and Electronics Engineers (IEEE). His research contributions are in information and communication technology.

Early life and education Liu grew up in Taichung, Taiwan, where he attended St. Viator Catholic Junior High School. After graduating from Taichung First Senior High School, he studied electrical engineering at National Taiwan University and received a Bachelor of Science (B.S.) in 1983. He then served two years in the Republic of China Armed Forces and earned a master's degree from the University of Michigan in 1987. In 1990, he earned his Ph.D. from the University of California, Los Angeles, under Kung Yao.

Career Liu joined University of Maryland, College Park, in 1990, and a Distinguished Scholar-Teacher and also Christine Kim Eminent Professor of Information Technology at Electrical and Computer Engineering Department of A. James Clark School of Engineering. of which 13 are now IEEE fellows. According to the Mathematics Genealogy Project, he has had over 200 Ph.D. descendants. He retired from the University of Maryland at the end of 2021.

Liu founded Origin Wireless in 2013, and pioneered ambient sensing and intelligence by leveraging the ubiquitous radio waves around us as the new sixth sense to decipher human activities, secure home, provide better health care, automate intelligent space, without using any proprietary devices or wearables. Origin was acquired by ADT, Inc. in February 2026. 2017 CEATEC Grand Prix, and the 2021 Red Dot Design Award.

Liu was the 2022 IEEE President and CEO. He has served as the 2019 IEEE Vice President - Technical Activities, Division IX Director of IEEE Board of Directors in 2016–17, and the President of IEEE Signal Processing Society in 2012–13. He was also the Editor-in-Chief of IEEE Signal Processing Magazine in 2003-05. Liu was a founder of Asia-Pacific Association of Signal and Information Processing (APSIPA). the world's first digital surveillance system through the Internet when the only available surveillance systems were analog. the 2021 IEEE Fourier Award for Signal Processing with the citation "For outstanding leadership in and pioneering contributions to signal processing for wireless sensing and communications", and the 2016 IEEE Leon K. Kirchmayer Graduate Teaching Award "for exemplary teaching and curriculum development, inspirational mentoring of graduate students, and broad educational impact in signal processing and communications". Recognized by Web of Science as a Highly Cited Researcher (2001–2014, 2016–17), Liu is a member of National Academy of Engineering for contributions to signal processing for wireless sensing and communications, and a fellow of the IEEE, for contributions to algorithms, architectures, and implementations for signal processing. Liu is also a fellow of the American Association for the Advancement of Science, and National Academy of Inventors. He was honored as 2021 Distinguished Alumni of National Taiwan University. His research was featured as one of seven technologies that IEEE believes will have the world changing implications on the way humans interact with machines, the world and each other, in honor of IEEE's 125th Anniversary. for "influential technical contributions and profound leadership impact"; IEEE Signal Processing Society 2009 Claude Shannon-Harry Nyquist Technical Achievement Award "for pioneering and outstanding contributions for the advances of signal processing in multimedia forensics, security, and wireless communications"; APSIPA 2018 Grand Award; 1994 National Science Foundation Young Investigator Award; IEEE Signal Processing Society Distinguished Lecturer; IEEE Signal Processing Society Meritorious Service Award; EURASIP Meritorious Service Award,

He also received various research and teaching recognitions from the University of Maryland, including Poole and Kent Senior Faculty Teaching Award (2005), Outstanding Faculty Research Award (2008), and Outstanding Service Award (2012), all from A. James Clark School of Engineering; Invention of the Year Award (three times) from the University's Office of Technology Commercialization, as well as the George Corcoran Award for outstanding contributions to electrical engineering education from the Electrical and Computer Engineering Department, and the Outstanding Systems Engineering Faculty Award in recognition of outstanding contributions in interdisciplinary research from Institute for Systems Research. It was earlier than technology readiness for such a dramatic paradigm shift, but now time-reversal is a promising technology being considered for 6G wireless communications.

Using the time-reversal principle, he also developed the world’s first centimeter-accuracy indoor positioning and tracking system in 2015 with only a single transmitter and terminal device, both with a single antenna, in a completely non-line-of-sight environment. It represented the first non-line-of-sight, non-triangulation technique for accurate position estimation, solving a long-standing conundrum of indoor positioning/tracking for over many decades. This discovery enabled precise speed estimation in complex indoor settings, a task previously considered insurmountable. By establishing a principle that succeeds where the Doppler Effect fails, his work enabled accurate tracking of an unlimited number of subjects, indoors, and without costly infrastructure or a priori measurements, it also served as the theoretical foundation for accurate/reliable wireless sensing by simply using ambient radio waves, including Wi-Fi.

Remoteeyes was the world's first digital video surveillance system to monitor and secure home/office through the Internet remotely.

Liu pioneered cross-layer design using antenna arrays for wireless communications in 1997 by first introducing the concept of duality between uplink and downlink for joint transmit beamforming and power control to increase the number of users in a cellular network by a factor of 100.

When the narrowband space–time codes were exciting the research community, there have been many attempts in the research community to search for the broadband full-diversity space-frequency code or even the full-diversity space-time-frequency code. Liu's group showed for the first time in 2003 that the maximum achievable diversity order with arbitrary channel power delay profile is a product of the number of delay paths, the rank of the channel temporal correlation, and the number of transmit and receive antennas. With that his group developed the world’s first full-diversity, full-rate space-frequency code and the only available systematic space-time-frequency code that achieves the maximum achievable diversity in space, time, and frequency for broadband wireless communications by exploiting all of the available spatial, temporal and frequency diversities in broadband wireless systems. This work provides a first step toward achieving full-diversity in multiple-input multiple-output (MIMO) broadband OFDM systems that are commonly used in modern wireless communications standards such as 4G/WiFi and beyond.

He made significant contributions to cooperative communications and networking by holistically addressing performance, coverage, energy efficiency, and throughput.

Liu published early research in multimedia forensics and security. His 2005 book, Multimedia Fingerprinting Forensics for Traitor Tracing laid the foundation of this emerging field, in which he contributed new concepts, such as anti-collusion codes, behavior forensics, and anti-forensics. He coined the name “information forensics” when proposing the journal IEEE Transactions on Information Forensics and Security. "Reciprocity, Evolution, and Decision Games in Network and Data Science", Cambridge University Press, 2021 "Wireless AI: Wireless Sensing, Positioning, IoT, and Communications", Cambridge University Press, 2019 "Cognitive Radio Networking and Security – A Game Theoretic View", Cambridge University Press, 2010 "Cooperative Communications and Networking", Cambridge University Press, 2009 "Ultra-Wideband Communication Systems: The Multiband OFDM Approach", Wiley, 2007 "Network-Aware Security for Group Communications", Springer, 2007 "Multimedia Fingerprinting Forensics for Traitor Tracing", Hindawi, 2005 "Handbook on Array Processing and Sensor Networks", Ed., IEEE-Wiley, 2009