Dr. Philipos Loizou, a pioneer in the field of hearing aid and speech enhancement, died late last month of cancer. He was 46.
Loizou was an internationally known leader in signal and speech processing, speech perception and cochlear implants – electronic medical devices attached to the inner ear of profoundly deaf people that send sound signals to the brain. His algorithms also helped improve the performance of cochlear implants by programming the devices to operate more effectively in a range of listening conditions.
“He was the first person to develop specific speech enhancement algorithms that directly improve intelligibility – previously believed not to be possible,” said Dr. John Hansen, head of the Department of Electrical Engineering. “More than his research, Philip was a true scholar – always looking to make contributions which would help improve the quality of life of people with hearing loss.”
A Cecil H. and Ida Green Professor in Systems Biology Science, Loizou developed an interface that enables smartphones and personal digital assistants, or PDAs, to process acoustic signals, such as speech, through a microphone worn behind an individual’s ear. It sends the processed signals to electrodes implanted in the inner ear. This interface was approved by the Food and Drug Administration, and Loizou was overseeing a clinical trial on the interface. At the time of his death, he was also working on basic scientific research with animals, looking at how the auditory system reacts to electrical stimulation.
He has been the principal investigator on several significant grants and contracts funded by the National Institutes of Health and received the NIH Shannon Award in 1998. He was known for mentoring his students and helping other faculty members at UT Dallas garner support from the NIH.
“He sought out collaborations which would later become some of the most profound contributions in the field,” said Hansen, holder of the Distinguished Chair in Telecommunications. “In addition to his work, he was a valued colleague, mentor and academic citizen. In true Philip style, he always brought a careful, thoughtful approach to all he did and made all around him better.”
Loizou attributed much of his success to his students.
“I’ve had very hardworking and dedicated students,” he said earlier this year. “Without them, I find it’s difficult for me to progress in my research, so I owe a lot of praise to them.”
Loizou grew up on the island of Cyprus. At the time, there was no university there, so he went to Arizona where he had family. He earned his bachelor’s, master’s and doctoral degrees in electrical engineering from Arizona State University in Tempe, where he also completed a postdoctoral fellowship. His focus was mostly on processing speech for machines, the engineering side of speech processing and recognition, until what he called serendipity gave him the opportunity to work with a professor researching cochlear implants.
“I left his lab and kept pursuing it,” he said. “I found it very gratifying because it’s research that could affect people’s lives.”
Loizou taught at the University of Arkansas in Little Rock before joining the Erik Jonsson School of Engineering and Computer Science faculty in 1999, where he helped co-found the Center for Robust Speech Systems (CRSS) in the Jonsson School and directed the Speech Processing and Cochlear Implant Labs within CRSS.
He was a fellow of the Acoustical Society of America, the highest honor awarded in the field of acoustic signal processing. He authored or co-authored more than 170 publications, including the book, Speech Enhancement Theory and Practice (Signal Processing and Communications).
“He spent countless hours reading and editing not only journals and papers, but also filling his passion for the arts with poetry, short stories, paintings and much more,” said his wife, Demetria Loizou.