Thomas E. Tremain, a pioneer in the field of digital speech coding, died of cancer on October 5, 1995, at age 60. He was a recognized leader and expert in speech science. His work spanned five decades of state-of-the-art modem and speech coding innovations that are the basis of virtually every U.S. and NATO modem and speech coding standard. His original work on channel vocoders, continuously variable slope delta modulation, linear predictive coders, adaptive predictive coders, code excited linear predictors, modem technology, channel simulation, and intelligibility and quality test methodology forms the basis of most voice communications used today.
Tom made remarkable contributions to the work of both the U.S. Department of Defense and NATO and to the speech community at large. He was a friend to everyone in the speech community and touched many as the most frequent session chair of the IEEE's International Conference on Acoustics, Speech, and Signal Processing, of which he never missed a meeting. He won U.S. Meritorious Civilian Service Medals in 1985 and 1992 and a special award from the IEEE Signal Processing Society in 1993 for his major contributions and sustained leadership in digital speech coding, modem technology and U.S. and NATO Standards for speech coding and communication. Tom was the National Security Agency's chief speech scientist, the chair of the Department of Defense Digital Voice Processing Consortium ( DDVPC ) , and the chair of the NATO Narrowband Speech Working Group.
Tom's unique ability to interpret diagnostic rhyme and diagnostic acceptability tests to pinpoint weaknesses in speech coding algorithms and systems led people from all over the world to seek his expert advice to improve their systems. Every U.S. and NATO narrowband speech coding standard developed over the past three decades has benefited from Tom's diagnosis. Tom's professional dream was always ''plain text 2400'' ( transparent speech quality at 2400 bps ) . In the final hours of his career, he did what he enjoyed most -he helped candidates tune their algorithms for the DDVPC's emerging 2400-bps speech coding standard. The excellent quality of these new coders put a smile on Tom's face -his career goal had been met. Although his personal contributions were enormous, he was most proud of the new generation of speech researchers whom he nurtured to carry on his work. Tom's brilliant career is described in the article ''A History of Voice Coding : Insights Drawn from the Career of One of the Earliest Practitioners of the