John M. Cioffi

To John M. Cioffi, for contributions to multicarrier communications and high-speed digital subscriber line technology.

Hitachi America Professor Emeritus of Engineering, Stanford University, California

  • BS, 1978, Electrical Engineering, University of Illinois at Urbana-Champaign
  • MS, 1979, Electrical Engineering, Stanford University
  • PhD, 1984 , Electrical Engineering, Stanford University

John M. Cioffi is best known for his contributions to the theory and practice of high-speed digital communications. After completing his degree at Illinois, Cioffi went to work as a modem designer at Bell Laboratories. During that time, he completed his master’s and doctoral degrees at Stanford University. In 1984 and 1985, he worked for IBM doing research on disk read channels. In 1986, Cioffi joined the faculty of Stanford University, where he has focused his research on discrete multitone technology (DMT) and asymmetric digital subscriber lines. To transfer this research commercially, he founded Amati Communications Corporation in 1991 and served as its chief technology officer until Texas Instruments acquired it in 1997.

Digital subscriber line (DSL) service is a broadband digital transmission service offered on ordinary copper pair telephone lines. Versions of DSL date from the mid 1980s, but the data rates and reliability were not adequate for widespread adoption. Cross-talk and transmission variations across the frequency spectrum due to line length and other factors were central problems. In the early 1990s, Amati suggested a highly adaptive DMT approach, which became the basis for all the modern DSL standards in use today and allowed significantly higher data rates than had been believed to be possible.

Cioffi has published more than 90 journal articles, presented approximately 200 conference papers, and holds numerous patents. His publications have garnered best paper awards from the IEEE Communications Society (1990), the IEEE International Conference on Communications (2006, 2007, and 2008), IEEE Communications Magazine (2007), and the IEEE International Symposium on Subscriber Loops and Services (2004). He was named a Marconi Fellow in 2006 and this year received the IEEE Alexander Graham Bell Medal.

Current as of 2010.