Electronic Computer Laboratory, Indian Statistical Institute, Calcutta, India – Assistant Engineer from August 1956 to August 1958
Cornell University, Ithaca, New York - Assistant Professor of Electrical Engineering from June 1962 to June 1965
Bell Telephone Laboratories, Holmdel, New Jersey - Member of the Technical Staff from June 1965 to January 1967
University of California, Davis, CA - Associate Professor of Electrical Engineering from January 1967 to June 1971
Professor of Electrical Engineering from July 1971 to June 1977, University of California, Davis
University of California, Santa Barbara, CA - Professor of Electrical Engineering and Computer Science from July 1977 to December 1978
Professor of Electrical and Computer Engineering from January 1979 to June 1987, University of California, Santa Barbara
Professor Above Scale from July 1987 to June 2006, University of California, Santa Barbara
Research Professor from July 2006, University of California, Santa Barbara
University of California, Santa Barbara, Vice-Chairman of the Department of Electrical and Computer Engineering from April 1979 to June 1979
University of California, Santa Barbara, Chairman from July 1979 to June 1982
University of Southern California, Los Angeles, CA - Stephen and Etta Varra Professor Emeritus, Ming Hsieh Department of Electrical Engineering from July 2006 to May 2012
University of California, Berkeley Teaching Assistant and later Associate from September 1958 to June 1960
University of California, Berkeley Graduate Research Engineer from September 1960 to June 1962
University of California, Berkeley Associate from January 1962 to June 1962
Bell Telephone Laboratories, Murray Hill, New Jersey - Member of the Technical Staff from June 1962 to September 1962
Faculty Advisor, Pi Kappa Alpha Fraternity, Cornell University, Ithaca, New York, from 1963 to 1964
GTE Lenkurt Electric Company, San Carlos, California - Staff Engineer from June 1967 to September 1967
Ampex Corporation, Redwood City, California - Consultant from March 1968 to June 1969
Stanford Linear Accelerator Center, Menlo Park, California - Visiting Scientist from June 1969 to August 1969, and from July 1972 to September 1972
Lawrence Livermore Laboratory, University of California, Livermore, California - Staff Engineer from July 1974 to September 1974
Lawrence Livermore Laboratory, University of California, Livermore, California - Consultant from September 1974 to September 1993
Siliconix Ltd., Santa Clara, California - Consultant, 1980
U.S. Army Ballistic Missile Defense Advanced Technology Center, Huntsville, Alabama - Consultant, 1980-1981
Fairchild Semiconductor, Palo Alto, California - Consultant, 1981
Harper and Row, Publishers, Inc., New York, New York - Series Advisor, January 1982 to September 1987
HDR Sciences, Santa Barbara, California - Consultant, May-June 1981
General Motors Delco Electronics Division, Goleta, California - Consultant from May - June 1983
International Advisory Panel, Chinese University Development Project I, National Academy of Sciences, and the Ministry of Education, People's Republic of China - Consultant from July - August 1983
Los Alamos National Laboratory, Los Alamos, New Mexico - Consultant from June 1984 to the June 1987
International Advisory Panel, Chinese University Development Project II, National Academy of Sciences, Washington, D.C. and the Ministry of Education, People's Republic of China - Consultant, January 1985
National Semiconductor, Santa Clara, California - Consultant from March 1999 to March 2000
Visiting Professor, Department of Electrical Engineering, Indian Institute of Technology, New Delhi, India – (September 1972 - April 1973)
Visiting Professor, Department of Electronic Engineering, Kobe University, Kobe, Japan – (May - September 1973), (November – December 1988), (March 1997)
Visiting Professor, Institüt für Nachrichtentechnik, University of Erlangen-Nürnberg, Erlangen, Germany - (September - December 1975), (June - December 1989), (July -September 1996), (July 2013)
Visiting Fellow, Australian National University, Canberra, ACT, Australia – (July - December 1982)
Visiting Research Professor, Tampere University of Technology, Tampere, Finland, (June -July 1984)
Visiting Professor, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil - (August 1984)
Visiting Professor, Electrotechnical Faculty, University of Zagreb, Zagreb, Croatia – (August 1986)
Visiting Professor, Department of Electrical and Electronic Engineering, Technical University of Istanbul, Turkey – (September-October 1988)
Visiting Professor, Department of Electrical Engineering, Bilkent University, Ankara, Turkey – (October 1988)
Visiting Professor, Institüt für Theoretische Elektrotechnik und Messtechnik, University of
Karlsruhe, Karlsruhe, Germany - (June - September 1992)
Visiting Professor, Institüt für Nachrichtentechnik und Hochfrequenztechnik, Technical University of Vienna, Vienna, Austria - (August - September 1994)
Visiting Professor, Department of Electrical Communication Engineering, Indian Institute
of Science, Bangalore, India – (June – July 1997)
Visiting Professor, University of Strathclyde, Glasgow, U.K., and University of Edinburgh, Edinburgh, U.K. - (June - July 1999)
Visiting Scientist, Research & Development Center, Telenor, Kjeller, Norway - (AugustSeptember 1999)
Nanyang Professor, Nanyang Technological University, Singapore (October 2002), (November 2004)