Oral-History:Louis Scharf

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About Louis Scharf

Louis L. Scharf (Life Fellow, IEEE) received the Ph.D. degree from University of Washington, Seattle, WA, USA, in 1969. He is currently Research Professor of Mathematics and Emeritus Professor of Electrical and Computer Engineering at Colorado State University, Fort Collins, CO, USA. He holds a courtesy appointment in Statistics. He has coauthored the books, Statistical Signal Processing: Detection, Estimation, and Time Series Analysis, Addison-Wesley, 1991, Statistical Signal Processing of Complex-Valued Data: The Theory of Improper and Noncircular Signals, Cambridge University Press, 2010. His coauthored book, A First Course in Electrical and Computer Engineering, Addison-Wesley, Reading, MA, 1990, was republished by Connexions in 2008. The coauthored book, Coherence in Signal Processing and Machine Learning, Springer, will appear in Fall 2022. His research interests include statistical signal processing and machine learning as they apply to space-time adaptive processing for radar, sonar, and communication, modal analysis for electric power system monitoring, spectrum analysis for nonstationary times series modeling, hyperspectral imaging, and image processing for group-invariant classification and registration. Prof. Scharf was the recipient of several awards for his contributions to statistical signal processing, including the Technical Achievement and Society Awards from the IEEE Signal Processing Society, Donald W. Tufts Award for Underwater Acoustic Signal Processing, Diamond Award from the University of Washington, and 2016 IEEE Jack S. Kilby Medal for Signal Processing. In 2021, he received the Education Award from the IEEE Signal Processing Society.

About the Interview

LOUIS SCHARF: An Interview Conducted by Michael Geselowitz, Center for the History of Electrical Engineering, 18 August 2022

Interview #882 for the IEEE History Center, The Institute of Electrical and Electronics Engineers, Inc.

Copyright Statement

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Request for permission to quote for publication should be addressed to the IEEE History Center Oral History Program, IEEE History Center, 445 Hoes Lane, Piscataway, NJ 08854 USA or ieee-history@ieee.org. It should include identification of the specific passages to be quoted, anticipated use of the passages, and identification of the user.

It is recommended that this oral history be cited as follows:

Louis Scharf, an oral history conducted in 2022 by Michael Geselowitz, IEEE History Center, Piscataway, NJ, USA.

Interview

INTERVIEWEE: Louis Scharf

INTERVIEWER: Michael Geselowitz

DATE: 18 August 2022

PLACE: Virtual

Early life and Education

Geselowitz:

Okay, great. So I’ll just do a little, a little introduction. This is Mike Geselowitz from the IEEE History Center. Today I’m conducting an oral history interview with Louis Scharf via Zoom. I am at my home in New York, and he is at his home in Colorado. So with that, Louis if you don’t mind, would you start, tell us about your childhood and how you got interested in engineering and technology?

Scharf:

Well, I grew up in a small town in southwest Washington, Longview, Washington. I have two siblings, one younger sister, one younger brother. Longview, Washington was a highly industrialized, blue-collar town, which at that time had two of the largest lumber mills in the world, Weyerhaeuser and Long-Bell, had large paper companies, Weyerhaeuser Paper and Longview Fiber. Reynolds aluminum company had a plant there as well. This town lay right at the confluence of the Cowlitz and Columbia Rivers, so it was a busy shipping port called the Port of Longview. My father was an electrician in Hanford, Washington during the Second World War, and after the Second World War he and my mother started a company called Scharf Electric and ran that business for 20 years quite successfully. On weekends, from an early age, I worked as a shop boy for Scharf Electric. And in my late high school years and early college years, I actually held an IBEW union card as an apprentice electrician and worked for Scharf Electric in summers. I went to R.A. Long High School and graduated in a class of 360. I was a determined schoolboy student and athlete. I and my peer group studied at R.A. Long Library and played basketball, baseball, golf, and table tennis. That’s what you did in the 1950s. Actually I don’t know if it’s in spite of the nature of the town or because of the nature of the town, but a lot of very successful people came out of R.A. Long High School. And if you came out of R.A. Long High School and went to university, you went to university to study mathematics, physics, chemistry, engineering, something technical. That was just the nature of our upbringing. As I said in some of my notes to you, I was just a rising junior in high school when Sputnik was launched, and that changed the environment for everybody. It was palpable. If you had any interest in mathematics, physics, chemistry, you felt yourself swept along into what we now call STEM during what was the space race. So that was kind of my early childhood. Our high school class sent students to Princeton, to MIT, Rensselaer, and several of us to the University of Washington, which is where I enrolled. And I don’t know, maybe that kind of brings you up to date on my early childhood.

Geselowitz:

So that’s great. Why did you choose Washington? Because it was close to home, because it was the state school?

Scharf:

My parents were very intelligent and active citizens of the community. It was a foregone conclusion that all of their children would go to university, even though they had not. We didn’t know that much about enrolling in a university, but one of the kids in the neighborhood had these two older sisters who had enrolled at the University of Washington. And so, I don’t know, they kind of coached us through it and I had some other classmates going to the University of Washington. I just did what everybody else was doing.

Geselowitz:

How about when you got there, did you do, you said that several people in your high school did go into technical careers. How did you end up majoring in engineering?

Scharf:

Well, as I say, if you come out of a blue-collar town like Longview, Washington and you’re going to university, you’re going to go to university to study a STEM subject. And coming out of a small town high school like that, I don’t think I would’ve known what it meant to be a mathematician or a physicist or a chemist, but growing up in the environment I grew up in and having several friends whose fathers were engineers at Longview Fiber or Weyerhaeuser, and having worked as an apprentice electrician, I kind of had an idea of what an engineer might do. So I suppose this explains why I chose engineering.

Geselowitz:

Okay. And did freshman year encourage you or disappoint?

Scharf:

Well, I was a desultory student to begin with. I joined a fraternity at the University of Washington and got swept up in the fun times of fraternity life. And I got off to kind of a rocky start. And then as I engaged with some faculty in electrical engineering somewhere along the line, I got traction. I was inspired by many of the faculty members at the University of Washington. So I’d say my first two years were quite unsatisfactory from the point of view of performance. I had one of these minimax strategies, minimum effort, maximum result. And I certainly achieved minimum effort.

Geselowitz:

When you got to higher levels, what were your courses like? What sort of electrical engineering did you get to study?

Scharf:

Well, this gives me a chance to contrast electrical engineering curricula then with electrical engineering curricula now. The first thing is we had a quarter system, so we took three halves as many courses as students in semester systems. They were shorter in duration; they were like nine or ten weeks as opposed to 14 weeks. And really it was an engineering science education. We took mathematics all the way through differential equations, and you could elect complex variables. We took a full year of physics and then an extra quarter of modern physics, studying quantum mechanics and special relativity theory. We did courses in statics, dynamics, and advanced dynamics. We did fluid dynamics. We did strength of materials; we did chemistry. I actually did a physical chemistry course. And so we took a broad range of technical and scientific courses. And of course we took our liberal arts courses in the, I can’t remember, College of Liberal Arts or College of Arts and Sciences then. And then in electrical engineering, we had a great education. I mean, we studied circuits, a challenging circuits course, I would say, quite challenging compared with what I see now. We did courses in electromagnetic fields and transmission lines. We did courses in solid-state electronics. Actually at that time, the transistor had been invented, I guess in 1947 or 1948, and I was in undergraduate school from 1960 to 1964. We had a lab where we attempted to build a point-contact transistor, which is the first transistor built at Bell Labs before the solid-state junction transistor. And as I recall it, we never got this point-contact transistor to work, but we were working at it. I remember writing one or two computer programs because at that time there was no computer engineering. I graduated in 1964. There was no computer engineering. We had a computer center down near the small nuclear reactor the University of Washington had, and we’d carry these big boxes of cards down to the computer center.

Geselowitz:

So, was it an IBM mainframe?

Scharf:

Yes, an IBM mainframe.

Geselowitz:

Probably an IBM?

Scharf:

Probably, I don’t remember. And you’d slip your cards into a little cubby hole and come down later at night and you’d find one of these printouts, one of these alternating green/white printouts with the track holes on the side. And it would say fatal error. Okay, so then you go back to your office, and you’re trying to figure out what’s going on. But, basically, I never really learned to program as an undergraduate. I just hacked away at Fortran. And we wrote some kind of program to approximate the solution to one of those traveling salesman problems. That’s what I remember. And okay, we did courses in Fourier analysis, we did courses in power, communication theory, control theory, so we had a very broad education in electrical engineering. But the thing that distinguished it was this very broad education in engineering science. We took the dynamics courses in mechanical engineering, we took fluid mechanics in the civil engineering department, strength and materials we took in a material science department. So we took courses in many, many departments. Really there was, I’m repeating myself, but we never really did electronics, besides this experience with a point-contact transistor. I remember just reading out of some SEEK notes about designing with transistors, but we never really did anything serious in the way of circuit design. It was all sort of engineering science.

Geselowitz:

And did you have any opportunity in the summers to do work for local industry?

Scharf:

Except for electrician work, I never did have what you’d call an apprentice engineering experience. Now in graduate school, I was fortunate to have as a graduate advisor, a man named Dean W. Lytle. He was the most important consultant at Honeywell’s Marine System Center, and he got me a consulting job in graduate school, which I had for I guess, two or three years. So I had a one-day-a-week consulting job at Honeywell’s Marine System Center. And I always choose my words carefully when I tell people this. I tell them that until I started working at Honeywell, “I didn’t really understand what it was I thought I was trying to do in my research program.” But when I got to Honeywell and began working on problems in underwater acoustics, underwater signal processing, mostly active signal processing, transmitting active pulses to detect various kinds of surface and undersea vehicles and building out tracking algorithms and that sort of thing, I immediately began to understand what it was I thought I was trying to do in my detection, estimation, and time series work as a graduate student.

Boeing and Honeywell

Geselowitz:

So you went straight from the BS program to the MS program at University of Washington?

Scharf:

I did not. Actually I went to The Boeing Company for about 16 months, and I had a very rudimentary job as an engineer. My job was to pore over printouts from telemetered data that came from Minuteman missile tests at the Vandenberg Air Force Base. These missiles were fired fairly regularly. Sensors on the missile transmitted data, telemetered data, to a base station. That data was printed out and sent to us at Boeing. We pored over it for any anomalies. It was not interesting, but somewhere along the line, I confronted a least squares problem, and I didn’t know anything about it. My engineering manager pointed me to an experienced engineer a couple floors down from me to learn what I could about least squares theory. And well, that really kind of energized me. And so that was just about, from a scientific or mathematical or engineering point of view, the only thing interesting I did at Boeing. I decided I was not having fun, I was not advancing, so I applied to graduate school and enrolled in graduate school at the University of Washington in 1966. And there I worked for a guy named Lynn Alexander Keeling Watt, a Canadian, who did solid-state electronics. He had an NSF grant to study what were called 3-5 compounds for solid-state electronics. They were studying diffusion in these 3-5 compounds. So I wrote a master’s thesis on diffusion in 3-5 compounds. But while I was doing it, I thought I invented a method that I called the method of phase plane displacements for solving the diffusion equation numerically. And I actually sent a paper to one of these winter annual meetings that the mechanical engineers hold. I didn’t go to the meeting, but it was published, and in response to the paper, somebody pointed me to prior work where this had already been done, so that was kind of sobering. Prof. Watt left to return to University of Waterloo in Canada. I had taken some courses in communication theory from Dean Lytle, and I was fascinated by it. So I hooked up with him as a graduate student in signal processing. He had graduate students in communications and signal processing. The environment for faculty in the 60s was completely different. I mean these faculty members, their job was to teach school, so to speak. And very few of them had funded research programs, so most of us were teaching assistants. I was a teaching assistant in an electromagnetics course. And then, as I mentioned in one of the documents I sent to you, somewhere along line the NDEA Title IV fellowship program was created in response to the space race and what, at that time was called the missile gap. That’s the way I remember it. There’s a space race. The missile gap, there was the competition with Russia; it was deemed that we were behind. So the senator from South Dakota, George McGovern, the candidate who got beat so badly by Nixon, marshaled this NDEA Title IV fellowship program through Congress, and I got an NDEA Title IV fellowship. From then on, I wasn’t a TA; I was an RA. And that, plus some money I borrowed from the Leona M. Hickman Award fund at the University of Washington, was enough to get me through graduate school. And as I said in other notes to you, I entered the University of Washington single in 1960 and graduated with a Ph.D. in 1969, married with two children. In graduate school I worked various part-time jobs, consulting at Honeywell, serving pizza … anything to pay bills and stay in school.

Geselowitz:

So you got married while you were in graduate school?

Scharf:

Yes. Married, what you would say is a high-school sweetheart.

Geselowitz:

So what was your first job out of your Ph.D. in 1969?

Scharf:

My first job then was to join Honeywell’s Marine System Center as a fulltime employee, what was called a principal engineer then. I stayed there for two years.

Geselowitz:

So you had kept your contacts with them after that initial internship?

Scharf:

Well I had been working with them one day a week all the way through graduate studies until I graduated, and then I took this fulltime engineering position there.

Geselowitz:

Okay. And what did you work on there?

Scharf:

Oh, all kinds of things. Signal design for active sonar systems, error analyses for various types of signal processing systems, basic detection theory. As I mentioned, in the materials I sent to you, Michael, I had an interesting episode with Hughes Aircraft. I don’t know if you want me to recount that or not.

Geselowitz:

Yes, that was a great story. If you want to briefly tell it “on tape,” that’d be terrific.

Scharf:

So much of what I’m telling you now, I didn’t actually know until about 1976 or so when I happened to read about something called the raising of the K-129, which was a Soviet nuclear submarine that had sunk in the North Pacific, north of Hawaii. So what I’m telling you, I learned in 1976. But if you go to a documentary movie on PBS from 2010 called “Azorian: The Raising of the K-129,” you’ll see the whole story of the US government effort to raise this Russian submarine. And it was actually funded by the CIA and it cost something over $300 million. But anyway, one day I was introduced to a gentleman from Hughes Aircraft who said that Hughes was interested in building a deep-sea drilling platform to drill for magnesium modules. And it was in 18,000 ft. of water and they needed to stabilize this platform so that they didn’t break off their drills. So this is the way it was explained to me. It turned out there was another group at Honeywell, unbeknownst to me, that was meeting with other Hughes representatives and they were designing these thruster systems they’d put on the corners of a platform. And they were also designing a so-called long baseline station-keeping system consisting of transmitters, transponders on the bottom about a mile away, transponding back to the original transmitter. And by measuring time delays, you could stabilize this platform because you’d know exactly where you were. I was tasked with the problem of doing the error analysis to find out whether at typical signal-to-noise ratios, with typical timing errors and with the sea surface bobbing up and down and this platform moving around so that its receiver was bobbing around a little bit. I had to do all the error analysis and deliver concentration ellipses, error ellipses, so that when you said we’re here, you could have a certain confidence that you actually were here. So I did this work, and that other work was going on in another part of Honeywell. Honeywell delivered this whole engineered system to the Azorian project. I think the boat the project was using was called the Glomar Explorer. I actually wrote up my work and submitted it to the winter annual meeting of the Acoustical Society of America and about the same time left for Fort Collins to take a faculty position at Colorado State University. And shortly after I got to Fort Collins, I got a letter saying that my paper had been withdrawn, and I had no idea why. And as I said, somewhere around 1976, I read an article about this Glomar Explorer project to raise the submarine. And then I realized that what I had been doing was the error analysis for the Glomar Explorer effort to raise this Russian submarine. So, when you’re a naïve engineer of 28, 29 years old-- I guess there was little skepticism.

Geselowitz:

Right, so instead of giving you clearance, they just told you it was a different project.

Scharf:

Yes, that’s exactly right. So that was interesting.

Geselowitz:

That’s a great story.

Scharf:

Actually, for people who are watching this, they might be interested in something else. I had nothing to do with the project I’m going to describe to you, but right across the hall from me were digital designers who were designing a rack of random logic hardware to deliver to the Naval Underwater Systems Center in San Diego to compute fast Fourier transforms. And Honeywell at that time designed a box to do a 256-point complex FFT at 8 bits of accuracy every 0.4 milliseconds. Now that was about the fastest real-time FFT box that I knew of, and that was being done not by me, but by others at Honeywell. And people watching this might be interested to see what the numbers looked like in 1960, 1969, ‘70, ‘71. They might want to compare that with what they can do with an interpreted language like MATLAB, sitting on their laptop.

Geselowitz:

At a café, right.

Scharf:

Yeah, so I just tossed that in as an interesting technological note

Geselowitz:

Thank you. Now, what made you decide to go back to academia?

Scharf:

Well, I don’t know. I always felt drawn to it. I had had a lot of positive feedback from the faculty at the University of Washington when I took the qualifying exam there and when I served as a TA and when I gave a few seminars and defended my masters thesis and PhD dissertation. Some people were quite complimentary about my ability to present what I was doing in something like an understandable manner. So I’d received some positive feedback. And I had always been captivated by people in academe who seemed to have a fundamental command of a topic area. And the idea of having command of a topic appealed to me. And I thought I’d have a better idea of developing a command like that in academe. So I took a salary cut by about a factor of two.

IEEE

Geselowitz:

Interesting. So now I’m just going to detour you a sec before we continue now, because now we’re going to get to really the meat of your career here. But little detour is about your IEEE involvement. When did you first become aware of IEEE as an organization?

Scharf:

Well, I think I was an IEEE student member. In fact, what I think I remember, people watching this might say I have some dates wrong, but I seem to remember that when I was an undergraduate student, somewhere between 1960 and 1964, there was the IRE, which was the Institute of Radio Engineers, and later it merged with another organization to become IEEE.

Geselowitz:

Right, in 1963. So you would’ve initially started as an IRE member. And in 1963, IRE emerged with AIEE to form the IEEE.

Scharf:

Okay, good. So what I remember is pretty close to right then.

Geselowitz:

Yes. Go ahead

Scharf:

I would have been aware of the IEEE then, and I think I became an IEEE student member somewhere along there.

Geselowitz:

And before I go further, were you also Eta Kappa Nu?

Scharf:

I was. And I just let that membership expire. I haven’t considered myself an Eta Kappa Nu member for, I don’t know, 40 years probably.

Geselowitz:

I only mention it because Eta Kappa Nu also eventually merged with IEEE.

Scharf:

Oh, is that right?

Geselowitz:

Yes, it’s now called IEEE-Eta Kappa Nu. So that happened about, I think about twelve years ago, something like that.

Scharf:

Well by then my Eta Kappa Nu membership would’ve been long dormant.

Geselowitz:

Long gone. Okay. And do you think, did you pretty much from then on stay, stay a member of IEEE though?

Scharf:

Oh, yes.

Geselowitz:

Okay. And did you, when do you first remember going to an IEEE conference?

Scharf:

Well, I do remember going to a conference which had a very short lifetime. It was something like the Mervin J. Kelly Conference on Communications. It was in Missouri, near the University of Missouri. I remember going to that conference. Maybe that was like 1970 or something like that. I’m just kind of guessing, but I do remember this Mervin J. Kelly conference, and it had a pretty short lifespan. Mervin J. Kelly was an important engineer at Bell Laboratories. And then I got quite active in IEEE, and I got quite active in the Signal Processing Society, served on its administrative committee. And then in 1980, we hosted ICASSP in Denver, and I was the technical program chair. At that time, I remember all the papers were mailed hard copy to us. And for the final decision, I gathered people from CSU and University of Colorado, and we had a meeting in Denver and accepted and rejected papers, and then we had to go back to New York City to have our decisions ratified. I remember schlepping all these papers back to New York City in cardboard boxes, and checking them through on the flight I took from Denver to New York City. So again, just to convey to people how much different things were then. And it sounds like I’m ranging all over the place, but I had a graduate student many years later who was reading one of my early papers. He was asking me how I generated those curves. And I said well, I had some data points, and I took a sheet with data points on it to an artistic woman named Hannah at the Engineering Research Center. She fit a French curve through these points and got out her Keuffel & Esser lettering and drawing kit, laid vellum over the sheet, taped it down, and inked in all this stuff to show experimental curves for an experimental result. And of course, he just couldn’t believe it. But that’s the way things were done back then. Paper, ink.

Geselowitz:

Yet a huge amount of progress was done in those years.

Scharf:

Yes.

Geselowitz:

If you look at engineering, electrical engineering, electronic engineering, signal processing, there was a huge amount of progress in the 70s.

Scharf:

Oh yes, no doubt. And actually I don’t know when you’d say the golden years were, but I mean the transistor was 1947, and information theory was 1948. And there was a lot of beautiful work that came out of the Radlab and Lincoln Laboratories after the Second World War, and that kind of laid the foundations really. Engineering in this country has been a very vital enterprise, extremely vital. And yes, I just happened to get caught up in some decades of it.

Colorado State University

Geselowitz:

You have had a long and distinguished career in Colorado, but I guess you left for a few years, is that correct?

Scharf:

Well, let me see. I was at Colorado State University from 1971 to 1981. I took a nine-month study leave at Duke University in 1974. Then I took a one-month study leave at La Plata in Argentina in 1981. And then I spent two months at the end of 1981 at the National School for Telecommunications in Paris, before I joined the faculty at the University of Rhode Island in 1982, and I was there from ‘82 to ‘85.

Geselowitz:

Now why did you go there? Did they ask you to be the chair?

Scharf:

They asked me to be the chair. And really the draw was a man named Donald Tufts there. He was one of the great eminences in signal processing, very scientifically minded. And he and I had got to know each other by running into each other at IEEE conferences. He called me and asked me if I had any interest in it. I had a mild interest in being chair, but I had a real interest in falling into orbit around him. So I went there for three years. Our family were fish out of water in New England, though. We had a hard time adjusting. We were kind of West Coast people by then, Westerners. And I had a chance to join the faculty at the University of Colorado, which also had a couple of very distinguished signal processing faculty, so it was a chance to return to Colorado. So in 1985, I returned. I moved to the University of Colorado in Boulder and remained there for 15 years. As a family we had a lot of study leaves and sabbaticals. We had a couple of fairly extensive leaves in Europe as a family. So we had a lot of really great international experiences as a family. When I had a chance to take a sabbatical or a study leave, I took it, but I never really left academe.

Geselowitz:

And so what were, over that career, what do you think were the high points of your research?

Scharf:

Well, I don’t know. I didn’t think I had written a very good Ph.D. dissertation, but I had one pretty good paper published in information theory transactions out of that. It was published in 1971, and it had to do with signal detection in noise of unknown level, which seems like a problem that should have been treated a lot, but it hadn’t been. And I used some fancy group theory and principles of invariance to derive a result. So that kind of got me started, and I think had I not published that, I probably never would have gotten a faculty position. I had some really great students early on at the Colorado State University, and we actually did a nice paper on the design of finite impulse response filters. Hasn’t gotten a lot of attention, but it was a nice piece of work. We had a result on stochastic approximation with correlated data, which one of my students published. And then somewhere along the line, I suppose it was under the influence of Don Tufts and Steve Kay, I got interested in what then were called subspace methods. And so I guess the things, probably what we’re best known for, is all the work we did on matched and adaptive subspace detectors. These have been quite influential. They’ve been used across a wide variety of disciplines. And so that work certainly counts. And I guess that would be the thing where we’ve had the most impact. We wrote an influential paper on modal analysis in power systems with a collaborator at Bonneville Power and with students at CU Boulder. And then with Ben Friedlander and with Tom Mullis, we did some work I really liked on spectrum analysis and time-varying spectrum analysis. Now recently, in collaboration with Spanish colleagues, and colleagues here in Colorado, we’ve gotten interested in variations on passive radar. With colleagues in Italy we have generalized a lot of work on adaptive coherence estimators (ACE) that had been done independently by them and by us. And this is an area where I think we’ll make some contributions. So I guess these would be the main topics.

Geselowitz:

You mentioned, that’s really great, very impressive, you also mentioned some of the work you do with your students. So what were some of the highlights of your teaching, over your long teaching career?

Scharf:

Oh, let me see. Golly, that’s hard to say. So when I first got to Colorado State University, I had a student who did an undergraduate student project on speech coding and decoding using a Bell Labs technology for generating pulse trains, white noise, and sinusoidal inputs to excite digital filters to synthesize speech, and the student actually got it to work. So that was pretty neat. I’ve always enjoyed teaching the courses in linear systems, probability theory, communication theory, detection and estimation theory. One thing I did that you might call innovative was to write a little textbook for a course at the University of Colorado which was called An Introduction to Electrical and Computer Engineering. And I taught that course for several years. It was a freshman course. And if I looked at the first freshman cohort that ever came out of that class, it would’ve been, I don’t know, about 30 students. I think something like six of them went on to do Ph.D.s in electrical engineering. You might say it was a successful course. So that freshman course was quite rewarding, and we ran a freshman seminar series.

Geselowitz:

So was that course designed as sort of a survey for students new to engineering school to see if electrical engineering was their thing? It was sort of across all of electrical engineering?

Scharf:

Well, definitely the seminar was. And the seminar invited people from the Boulder community to give talks about what they did as electrical engineers in private enterprise in Boulder. That’s exactly what that was.

But the freshman introductory course was an introduction to complex variables and circuits. It had some stuff on coding, it had some stuff on image transformations, had some stuff on circuit theory, had some applied math in it, just had a grab-bag of mathematical methods that would put them in good stead/ These methods were used for simple coding schemes, image transformations and so forth. So that was kind of a hardcore electrical engineering course for a first course. That was rewarding. But then, all my courses were at least rewarding for me. Now, I think you’d have to ask the students, but a lot of students have come back and said that some things that they had to choke down, they found in their later years to be quite nourishing. And I had a lot of fun in my courses. I had a lot of funny episodes in my courses that kept things kind of light.

Geselowitz:

Anything you can share without embarrassing your students?

Scharf:

Well, there are some things I wouldn’t share in the modern environment, things that everybody found humorous then but are in decidedly poor taste in the enlightened present, so I won’t relate those. I do remember one funny thing. I mean, you have to be a technical person to remember this, but I was lecturing on the board, and I had a bad habit of leaning back against the blackboard and then waving my arms to make a point and then returning to the board. And the students are giggling, and I didn’t know what was going on. They were looking at each other and exchanging sides and so forth, and I said what’s going on here? And they said, well Professor Scharf, you have a chalk psi on the back of your sweater where I’d been leaning up against the board. And I said, oh my God, that was supposed to be a phi. Okay. So things like this, just unimportant things that kind of kept things light.

Geselowitz:

So actually you mentioned changing social mores. When did women start to come into your classes in an appreciable number?

Scharf:

Well, electrical engineering is still having a very difficult time attracting women into its curricula. And I never remember having a large number of women in my classes. In fact, I think the stationary level now for women in electrical engineering is still something like 7% to 10%. It’s very low, although it’s much, much higher in biomedical engineering. So we never had a lot of women in our courses. When I graduated from University of Washington, we had one woman in our graduating class, and it was probably a class of 40 or something, so it’s been a real problem. But what I have observed, and I’ve said this many times, and many of my female faculty colleagues have validated this, and that is the following. First of all, if a woman does graduate as an electrical engineer, she will graduate as the top student in the class. This has happened many times at Colorado State University and the University of Colorado. The top student in the class will be a female student. But the other effect is that students come in their freshman year, and the male students will make a 2.5 to a 3-point grade point average and they’ll think, okay, I’m making my way. And a female student gets a 3-point to 3.5 average, and she thinks she’s failing. So she quits. And so this has been a real problem in engineering where these very, very successful female students, for the reason I gave or maybe some other reasons which we don’t understand, quit the discipline. And it’s a real problem. But I’m not the person to speculate about what the solutions are, because I haven’t studied the issue really. I’m pretty comfortable with the idea that I’ve been very supportive of the women students I have had, but I don’t think you’ll get any insights from me, Michael, about what the basic problems are and what the solutions are.

Geselowitz:

No, no, I’m trying to capture the history, the facts, right. We have to, the experts have to look at the facts and then try and figure out what is going on. Were you ever able to attract a female graduate student?

Scharf:

Okay, so I did have three very fine female master’s students at the University of Colorado. In my return to Colorado State University, I graduated a female Ph.D. in electrical engineering, who’s now at Qualcomm Research in San Diego.

Geselowitz:

That’s good.

Scharf:

I co-advised a female graduate student in statistics who’s now on the faculty in the Department of Mathematics and Statistics at Washington State University. I think that’s it. So you can see the numbers are pretty sparse

ICASSP

Geselowitz:

Yeah, interesting. Getting back to IEEE for a sec since I work for IEEE, I guess you were saying that the height of your Signal Processing Society career was when you actually hosted and were chair of ICASSP, which was, which was hosted locally in Denver.

Scharf:

That was probably the most demanding thing I ever did in the service of IEEE, yes.

Geselowitz:

I know what those big conferences are like. So what, what has your involvement been with the society since then?

Scharf:

Well, I don’t know. When you get older, young people come in, and with great enthusiasm to take their leadership roles. And when that happens, old people kind of step aside, which is my case. So I was the tutorials chair for the ICASSP meeting that was held in Salt Lake City. And I still review papers for IEEE. But I haven’t served as an associate editor for many, many years. So I guess you’d say my service is pretty low now, except that I, I still publish papers and I still review papers. I think that’s the extent of it now.

Geselowitz:

When did you officially quote/unquote retire, become emeritus?

Scharf:

Okay, so two things happened. First of all, I can’t remember when I became Life Fellow. I think you have to be a certain age…

Geselowitz:

So what happens is, its two separate processes. The Fellow process makes you a fellow, right. So a member can be a member, a senior member, or a fellow. But when you’re over 65 and your years of service plus your age exceed 100, you are given life designation, whatever your member level. So if you’re a member, you become a life member. If you’re a senior member, you’re a life senior member. In your case, if you’re a fellow, you become a life fellow. So theoretically the bottom-line case would be if you were part of IEEE for 35 years, you joined when you were 30, when you turn 65, you get to be, you get life designation. But it could be, if you join later, it could be later.

Scharf:

I told people that my parents actually took out an IEEE membership for me when I was born.

Geselowitz:

And I can certainly get those dates and fill them in.

Scharf:

Yes. So anyway, that happened at some point. But the question was emeritus. So actually in 2011, I took emeritus status from Colorado State University. That means you give up your tenure and stop teaching, but I went over to the math department and asked them if I might join the math department in some capacity. They gave me a research professorship in mathematics in 2011. So for the last 11 years I’ve called myself research professor of mathematics with a courtesy appointment in statistics. So, I’ve maintained all my close friendships and collaborations with my electrical engineering friends. And I’ve made a lot of new friends in mathematics with whom I’ve published, and with whom I co-advise students. I don’t serve as anybody’s advisor now where I have to look after their graduate program and so forth. But I have served as co-advisor for many students.

Geselowitz:

Sitting on committees and that sort of thing.

Scharf:

Yes

Geselowitz:

Wow. And what’s the, what do you see as a difference between what’s happening in the math and statistics departments and what’s happening in engineering departments since you’re in one of the more mathematical fields of electrical engineering, right. Sort of information theory, signal processing is much more mathematical than the circuits and systems folks, or the power folks.

Scharf:

Yes. Oh, well that’s a tough question. But of course mathematics is such a rich and dynamic discipline. I think I always knew it because I took a lot of math classes during my graduate studies at the university. But I’ve encountered new things like non-Euclidean geometries, which have had quite an influence on my thinking now about signal processing. All the insights and in some cases, some of the methods that come from reasoning about non-Euclidean geometry, things like subspace averaging, which is something we’ve been doing, we’ve made some contributions to, with colleagues in mathematics. I never would’ve found that in electrical engineering. But it’s given me a renewed appreciation for the mathematics that electrical engineers do because in some fields I see that what we do in electrical engineering in some fields is as good as the mathematics of mathematicians who also work in those fields. So you take some fields that electrical engineers and mathematicians work, and the quality of the work is pretty equivalent, I’d say. But of course it gets outside these applied areas, and you get in things like, as I say, non-Euclidean geometries, well then there’s work there that only mathematicians can do. It’s not a very good answer for you.

Geselowitz:

It’s pretty good.

Scharf:

I just want to make the point that mathematicians are interested in structure and form and generality. And so I think it might be the case that the mathematical work is maybe more basic in form and structure, and there’s more computation in electrical engineering, more working out of important details, computing, and of course inventing. I mean, engineering invention is different than mathematical invention.

Geselowitz:

Right. So I mean that’s great that you, you straddle departments, because it seems to me that like the mathematicians and all the mathematics aren’t always thinking about what the applications might be.

Scharf:

Yes.

Geselowitz:

And the engineers who need the math to do their applications might not understand the big picture.

Scharf:

I think that’s fair enough, yes. And you never know when some very deep abstract idea, which seems to have no relevance whatsoever, becomes important 20, 30, 50, 100 years now.

Closing remarks

Geselowitz:

Right. So the last question I wanted to ask, and then I will of course give you the final word, anything you want to add that you think we didn’t cover, you wanted to say, is in your travels, are there any particular events that sort of stick out in your mind? Like I know you visited China at one point, which must have been interesting at that time. So anything, any particular international conferences you went to that sort of, that sort of stick in your mind?

Scharf:

Well, of course I loved them all, but for the most recent one to China, I put together two visits. One was an ICASSP meeting in Shanghai. And then I followed it with a workshop in Xi’an. And at that time my son and his wife went with me on this trip, and we saw the horses and dragons at Xi’an. And of course that’s most remarkable work of man that I’ve ever seen. So that certainly stands out. But I mean, a lot of these conferences and workshops were great fun, very energizing, always meeting people, some of whom you had known of but never met in person, meeting some for the first time, stumbling across a paper. And this is really important. I mean, we’ve had a couple of cases where we’ve just stumbled across a paper or poster where somebody has been doing something and maybe we knew how to do it, and we were able to establish a collaboration with them and produce something of value. Or maybe they were doing something that we needed in our work, and a collaboration was established. So what I remember about these conferences is these one-on-one meetings with people to talk about what they’re doing and talk about what you’re doing. There’s an affiliated conference out in the Asilomar Conference grounds in Pacific Grove, California that I went to for, I don’t know, about 40 years until the pandemic hit. And that was a place where there were small presentation rooms, a small number of people. And those have always been very enriching. So it’s hard for me to pick one event as the most memorable. But I guess I’m not giving you an answer you want.

Geselowitz:

Particularly I want the answer that you want to give, so that’s fine.

Scharf:

The answer I want to give is that these international collaborations—either through visits, study leaves, sabbaticals, conferences, or international visits— are so enriching for the people you meet, the people you talk to, the new ideas you have, the new ideas they have. It’s the exchange of ideas; that’s what stands out. And I can’t pinpoint for you which idea I grabbed onto, in which city at which conference.

Geselowitz:

I got it. So actually one bonus question, I think about it, because you mentioned your family traveling with you. Did either of your children end up in technical fields?

Scharf:

Well, no, not really. My son was a very fine undergraduate physics student. He ended up completing his degree in political science, and he now owns a sporting goods store in BC Canada. So he’s very scientifically minded. And my daughter was a fine undergraduate student who completed a degree in biology and ended up doing a Ph.D. in nursing. She now serves on the faculty of nursing at the University of Pittsburgh.

Geselowitz:

Oh, wow.

Scharf:

But now that you bring up my children, and since we were talking about international travel and visits and so forth, our first sabbatical leave was in Paris. And I had an appointment at a place called Supélec, which was the Superior School for Electricity, with a joint appointment at the University of South Paris. Our family went there in 1977/78. Our children were 12 and 14, turned 13 and 15 shortly after we got there. We picked up a Volkswagen camper van in London, took it across the Channel, and had this camper van in a small village called Bures-sur-Yvette, southwest of Paris. We enrolled our kids in French-speaking schools the day we arrived. By Christmas they were fluent. In French. And during that one-year sabbatical, as a family of four, we spent 60 nights in this camper van traveling around Europe, the four of us. And that’s the kind of thing that either tightens a family or it doesn’t. And in our case, it tightened our family. It was just a tremendous family adventure.

Geselowitz:

It sounds like it. Wow, that’s amazing.

Scharf:

Yes.

Geselowitz:

So this has been really, really fascinating for me. I hope it was fun for you. Is there anything that you would like to add for posterity here? Again, you’ll get an opportunity to edit, if you think of something you want to add when you get the transcript, you can do that, but anything now you’d like to add that I didn’t ask about?

Scharf:

Well, all I would add is I’ve used very few names in this interview, but there’s a great number of people older than I, younger than I, some deceased now, who have had a tremendous impact on my intellectual development. And I think anybody in my situation who’s had a long career, an honest appraisal of what successes they might have had are really built on the successes of all these great people who were willing to talk with them, tolerate them, help them, work with them and so forth. And I’ve had a great class of graduate students, many of whom I still stay in touch with, who’ve done wonderful work. So I feel like, as one of my friends has always said, engineering is a team sport. And that’s the way I feel. I feel like I’ve played my position to some level of competence, but any success I’ve had are real team success.

Geselowitz:

And I’d like to think that, I mean, obviously you mentioned your students and your colleagues at your universities, but that some of those people you met through IEEE, through these conferences.

Scharf:

Oh, no doubt, absolutely. I’d say almost every one of these people that I’m alluding to is a member of IEEE.

Geselowitz:

But your students may have joined because you were a member.

Scharf:

Yeah, we always encourage them to, but if they’ve maintained their memberships, and I presume many of them have, that’s their choice.

Geselowitz:

Right, great. Okay, terrific. Well, again, thank you so much and have a great afternoon, and I’ll turn off the recording now.