Department of Electrical Engineering: Associate Professor in Communications Biophysics 1951--1957; Professor 1957-1984; Professor Emeritus 1984-; Research Laboratory of Electronics 1951-1969; Chairman, MIT Faculty 1967-1969; Associate Provost 1969-1971; Provost 1971-1980; Institute Professor 1975-1984; Institute Professor Emeritus 1984- .
