IEEE History Center: Ben Gold Abstract

Ben Gold was born in New York in 1923. He received an electrical engineering degree in 1944 from the City College of the City University of New York, and a Ph.D. from the Brooklyn Polytechnic Institute in 1948. His first position in industry was at the Avion Instrument Corp. in New York, where he worked on the theory of radar range and angle tracking. From 1950 to 1953, he was with Hughes Aircraft Company in Culver City, California working on statistical problems of missile guidance. He joined the staff at Lincoln Labs in 1953 working there through 1981 on the Application of probability theory to communications. He also designed and implemented a device to recognize hand-sent Morse code signals and a device to measure the pitch of speech for use in voice-coding systems. He contributed to the theory and application of voice coding systems for digital data rate reduction, the development of the theory of digital signal processing, and the design and development of high speed signal processing computers and parallel computers. His work in the 1950s on pattern recognition led to the first device that could automatically recognize hand-sent Morse code. In the late 1950s and early 1960s he developed a pitch detector for use with vocoders that became a standard algorithm. Many later pitch detectors were compared with the Gold algorithm. In the early 1960s, Dr. Gold, together with Charles Rader and Dr. Joe Levin, pioneered the emerging field of digital signal processing (DSP). They developed the concepts of digital filtering as it applied to audio problems; these concepts proved applicable to diverse fields such as radar, communications, sonar, seismology and biology. Of particular significance were developments of digital filter design methods in both the time and frequency domains, and analysis of quantization effects. He spent 1954 in Rome, Italy on a Fulbright Fellowship and served on the MIT faculty as a Visiting Professor during the 1966-67 academic year. He is a fellow of the IEEE (1972) [Fellow award for "contributions to speech communication and digital signal processing"] and the Acoustical Society of America. His IEEE awards include the Achievement Award (1972), the Society Award (1986), and the Kilby Medal (1997). He and Charles Rader wrote one of the first textbooks in the field of Digital Signal Processing.

The interview focuses throughout on the evolution of digital signal processing as a field and on the impact of the fast Fourier transform and of Linear Predictive Coding. Gold also describes his development of a pitch detector and his contribution to the construction of the Fast Digital Processor at MIT. A major theme is the manner in which the FFT allowed theorists within the DSP community to harness computing power to test their own theories, rather than turning their conclusions over to analog hardware specialists who would then build the appropriate test machinery. He also describes the social relationships among the researchers based at MIT and the dynamics of funding and managerial oversight at Lincoln Labs.

1	1948 Ph.D. in electrical engineering from Brooklyn Poly
	Jobs in New York and at Hughes Aircraft in Culver City, CA
	Joined MIT Lincoln Labs in 1953, stayed until retirement
	Early work on pattern recognition
	Conversation with John Kelly turns his attention to a pitch detector
2	Incorporates pitch detector into a vocoder at suggestion of Paul Rosen
3	Origins of digital filters
	Discussion of his work with Jim Kaiser and Charlie Rader
	Importance of FFT
	Influence of an exhibit at the New York Worlds Fair called "the Voder"
4	1954 Fulbright Fellowship study in Rome
5	Group leader Oliver Selfridge changes focus of group on Gold's return
	Transferred to Paul Rosen's group
	Pattern recognition group broken up
6	Trains himself to use computers
	Works with Wes Clark and the TX-2
7	Tests pitch detector on a Bell Labs vocoder
	Rosen urges him to build a vocoder
	Slowness of processing speech through these analog machines creates demand for digital processing
8	Jim Kaiser at Bell Labs suggests building digital filters
	Application of Hurewicz' work on sample data control systems
9	Charlie Rader joins group
	Joe Levin lectures on control theory, 1963
	Pressure from management who don't see the potential of DSP
	Involvement of Jim Kaiser, Hank McDonald
10	Visiting Professorship at MIT, 1966
	Meets Al Oppenheim
	Bruce Bogert develops cepstrum analysis
	Application to Oppenheim's homomorphic filtering
11	Tom Crystal, a TA, shows him internal draft of Cooley and Tukey's work on FFT
	Rader and Tom Stockham see applications of Cooley-Tukey paper to DSP
	Gold, Rader, Oppenheim, and Stockham collaborate on book on FFT
	Stockham's background, connection to Amar Bose
12	Stockham develops concept of High Speed Convolution
	Centrality of the FFT to the definition of the Field
	Distinction between discrete Fourier transform and FFT
13	FFT allows integration of theory and computation power
14	Influenced by Oliver Selfridge's work on pattern recognition
	Description of his pitch detector
15	Description of his course at MIT, 1966-67
	Relationship with Larry Rabiner and Tom Crystal
16	Sampling and quantization as problems confronting DSP
	Discussion of accuracy, and solutions to sampling and noise problems in DSP
17	Comparison of his work on quantization with that of Widrow
18	Hierarchy and social relations within DSP community at MIT
	Different skills, interests among the group
	Early involvement of radar specialists Ed Muehe and Bob Purdy
19	Construction of the Fast Digital Processor with Lincoln labs in house funds
	Application to radar research to demonstrate utility of project
	Development of Block Diagram Compiler at Bell Labs
20	Development of PATSY algorithm by Charlie Rader
	Development of Homomorphic Vocoder by Al Oppenheim
	Capacity of FDP to process FFT in parallel
	Rapid obsolescence of this hardware
21	Focus on Radar pushed by Jerry Dineen
	Louis Smullen [sp.] and Bill Siebert examples of those who did not recognize the digital revolution
22	FFT eventually allows mathematical/theoretical researchers to control their own hardware
	Impact of integrated circuits
23	Lee Jackson as example of researcher who went left the lab to develop hardware applications
	Integrated circuits allow for the programming of most DSP functions
24	Loss of interest in the field by mid-seventies
	Impact of Linear Predictive Coding in early 70s
	Ed Hofstadter's application of FDP to LPC allows coding in real time
25	His awareness of LPC through lectures at MIT by Schroeder or Atal
26	DSP synonymous with digital filtering before the advent of the FFT
27	Despite exit from field, he relies on its tools for work on speech
28	Recent innovations such as auto regression and maximum entropy theory
	These innovations not of the same magnitude as FFT, LPC
29	Reemphasizes importance of FFT and integrated circuits