| Imagining
the Unseen
 Aesthetic
Scientist interview with Khosrow Lashkari Ph.D., Executive Research
Engineer, Media Laboratory, DoCoMo USA Labs
Q: Can you tell us a little about your background and where
you grew up?
A: I was born in Tehran, Iran. I also went to high school and did
my undergraduate studies in Iran. Then I came here on a scholarship
and went to Stanford for my masters and Ph.D. in electrical engineering.
Q: What was your family like? Were you influenced from
anybody in your family regarding technology or engineering?
A: No, my mom was a housewife and my dad had a factory that produced
terrazzo tiles. I was just personally curious and interested in
math and physics - especially learning how things worked.
Q: Did you take things apart as a kid?
A: I would take things apart, yes. But back then; I didn’t
really have much to take apart.
Q: Today, you would have a field day.
A: Yes, that’s right – even with books. Libraries were
not that available. I had to take a bus 45 minutes to go to a central
library in Tehran to check out books. But in a way maybe it was
good, if you found a book, you really appreciated it and didn’t
take it for granted.
In my early days - when I was in seventh and eighth grade - I was
always fascinated by radio: It seemed so amazing that there was
this little device on a shelf not hooked up to anything other than
a power source - and magically, sounds came from it. I could hear
people hundreds or sometimes thousands of miles away. I was extremely
curious how this worked. I kept wondering, what was the invisible
link that makes this work? So when I was in tenth grade in high
school - about 16 years old - I built a small crystal radio. It
was a simple receiver, which had only three or four components,
but once you attached a piece of wire to it, you could pick up all
these radio stations.
Q: Sounds like a good early science experiment.
A: Yes. I was mostly curious how this little thing could pick up
signals from so far away? So I tried to learn more about radio waves,
and in 11th grade, I built a complete radio receiver with a box,
a loudspeaker and a red light for power. It was sitting in our house
for several years after I left the country. It continued to work
for a very long time.
Once I conceptually - and begrudgingly - understood radio waves,
I accepted that you can’t touch, hear, smell or see them,
but yet they exist. This was a very foreign concept at that time,
because we can perceive most of the things in the world with our
senses - but here was something that you couldn’t really detect
with any of your senses. Up to that point, I looked at the world
from a mechanical point of view - but here was an intangible, a
reality that exists but you can’t sense until you build a
device that detects it Once I understood how it works, I realized
that it’s basically like water waves - it is the same principle,
always the same laws and equations.
I also developed some fascination with mathematics, mathematical
tools and analysis, because if you write three or four lifeless
equations, lo and behold out of that falls this big equation that
predicts that such waves actually do exist. In fact, Maxwell predicted
that electromagnetic waves existed 20 years before Hertz discovered
them.
When I went to university, I studied electrical engineering. I
was extremely interested in electronics and in radio waves, so I
took a number of courses in electromagnetic wave propagation and
a lot of courses in electronics. One day when I was in the second
year of university, a group came from another university; they had
built a computer and were showing it off. At that time that was
pretty exciting.
Two of my friends and I decided that we should build one for our
university as a challenge - but that project didn’t go that
far because we were working on our own time and own budget and we
had very little money.
In my second year, I got involved in a lab project to build a voice
scrambling system. This was for a military application of secure
voice communications. That was where I really seriously started
in signal processing. When I was working on my earlier radio projects,
I learned that radio waves are really just half of the story; the
other half is how the signal is processed through various stages
like RF amplifiers, IF amplifiers, audio amplifiers and so on. So
I became seriously interested in signal processing.
As I mentioned, once I began the voice-scrambling project, I got
heavily into signal processing and have stayed there ever since.
On this particular project, we built a system that had about 25
printed circuit boards inside. We worked on it for about three years,
and then installed and tested it on airplanes – it was a real
product. You spoke into a microphone, and the system scrambled your
voice and sent it either over a telephone line or over wireless.
If it’s intercepted, the voices are unintelligible, so you
can’t understand what’s being said unless you know how
to decode it and unscramble it.
Q: What was your first university where you got into signal
processing and audio scrambling?
A: It was in Tehran. It’s called the Sharif University of
Technology. It was a new university at the time when I joined; it
was founded only two or three years before. Most of the faculty
were educated in the U.S. at really good universities like M.I.T.,
John Hopkins, Stanford - and the books were in English. One of the
requirements of getting into the university was you had to be able
to read and write in English very well, so you would pass a test
before being accepted. The lab was a two-story house on campus turned
into a lab - and it still exists. They also built early modems,
back in the 1970’s.
Q: What were the modems like that you built?
A: We built 300-baud modems, which at the time was good enough.
We would sell it to different departments and sometimes sell it
outside the university. In those days we had an IBM 1130 mainframe.
This was in the days where you only saw the computer through a glass
wall in an air-conditioned room.
Q: Do you mean main frame computers running on magnetic
tape?
A: Right, and punch cards. So you only see the tapes and all these
lights. You would run programs and basically punch them on these
cards and give the deck of cards to the computer center. Then you
come back in the afternoon or the next day to see if your program
worked or not and if it didn’t, there was some little thing
you had to change around those cards and turn it in. So it wasn’t
interactive at all. But these modems allowed you to remotely log
into the computer and get feedback. At the time it was really very
interesting. The speed was slow - 300 bits per second at first -
but then we also built faster ones; for example, I designed the
circuits for a 1,200 bps modem.
Q: Was that your undergraduate project?
A: No, my undergraduate project was building a PWM, or pulse width
modulation amplifier. This is a very efficient amplifier, meaning
that the amplifier itself doesn’t consume too much power.
PWM amplifiers are used today to drive loudspeakers. The scrambling
system and modems were after I graduated in 1972. I worked in the
lab until 1975, when I came to the U.S. to do graduate work.
Q: What got you to come to the U.S.?
A: I was working in that lab at the university for about three
years after I graduated. They were building a new university, needed
faculty and were giving financial scholarships to the students who
had high GPAs to go to Europe or the U.S. The condition was that
you had to get admission from top universities.
Actually, I was very happy working at the lab, but one morning
as I was passing by the president’s office I saw him waving
and I went in and he said, why aren’t you applying for this
scholarship? He gave me the forms, I filled them out and a week
later, they said okay, you’re approved for financial aid.
So I applied for Stanford, MIT and Berkeley, and I got admission
from all three of them.
In the end I decided to go to Stanford.
Q: So you went directly from Tehran to Stanford?
A: Yes. I landed in New York and the next day, flew to California.
Everything was different; the buildings, bridges, and airports.
Everything was on a much grander scale. It was like a new world.
Actually, when I was in high school, one summer I was teaching
one of my cousins English. There was this color book called Practice
your English; it was the story of a person traveling from the east
coast to California. It had beautiful color pictures of different
states, so when I was reading this book, I really got fascinated
with how beautiful America was and I told him, one day I will go
and travel like that. I arrived here in 1975. The next summer I
drove from California to New York and back. I went through many
different states. That early book and the pictures in that book
had a big influence on me. Of course, if not for the scholarship,
I couldn’t have come because I didn’t have the financial
means.
Q: Let’s talk a little bit about your work at Stanford.
What was your primary course of study there and what was your dissertation
on?
A: The primary course of study was initially data communications,
because that was where I left off - working on modems - when I came
from Iran. However, I later decided to work on speech coding - I
also had built the scrambling system, and was very interested in
speech and signal processing - my dissertation was on designing
a new speech codec that provided higher quality from the same amount
of information, the same number of bits.
Q: Where did you go from there? How did things develop?
A: From there, I went to work for a company in Palo Alto called
Systems Control Technology, where I again worked on speech coding
- because speech coding was a hot research area at the time. We
would write proposals for the military - Air Force, Navy and so
on. I was there from 1980 – I got into that company while
I was still working on my thesis – to 1986. I also worked
on a number of signal processing and sonar projects for detection
and classification of underwater objects – primarily ASW.
Q: What is that?
A: Acoustic Anti-Submarine Warfare - detecting and classifying
submarines. At the time - it was 1985 - the government put a lot
of money into those kinds of projects.
Q: Could you differentiate, say, steel from titanium? How
could you tell one vessel from another?
A: Actually, what we would do is we would use the engine frequency.
Soviet submarines had a primary engine frequency of 50 Hertz, and
you could tell one submarine from another by small differences in
the frequency – for example, one was 50 hertz and the other
was 50.01 Hertz.
Q: If you were doing it today would you do it differently?
A: Actually, if you would do it today, you don’t have much
choice. When you are under water sound really rules. That’s
the difference. Sound to water is like light to air. Air is transparent
to light and offers very little resistance. Light can travel very
long distances in air. Light comes from the stars hundreds of millions
of miles away and can keep on going almost forever. However, underwater
light quickly gets absorbed. Radio waves also get absorbed quickly
underwater, but sound travels thousands of miles. It is like being
able to hear a jet take off from New York when you’re in California.
If there was a jet under water taking off in Hawaii, you would hear
it in Monterey. In fact, later when I worked at the Research Institute
in Monterey, which was founded by David Packard, we were doing research
using underwater sound.
So the point is in answer to your question, you can’t do
much – I mean you can probably use better signal processing,
more computer power but in terms of what actually carries the information
from the source hundreds of miles away to you, sound waves are the
only physical mechanism that can do that.
Q: You’ve been a professor and an assistant professor.
When did you start teaching?
A: I was a teaching assistant at Stanford, and taught for one year
as a professor of electrical engineering at DeVry University in
Fremont. I had always wanted to teach so I took one year off and
did just that. Then I decided to get back into the industry and
had the opportunity to join DoCoMo USA Labs.
Q: It’s great kind of realizing your dreams along
the way.
A: Yes, actually I have been lucky really that I have worked on
very interesting projects. Like the one at the Packard Research
Institute, where we were trying to measure global warming by sending
sound waves from Australia and detected them in Monterey. We had
a receiver array of hydrophones or underwater microphones a mile
long. We deployed it off of Monterey and we were at sea on the ship
collecting data, resending the sound from Australia, which was 11,200
miles away. From the travel time of the sound, you could estimate
the speed of sound - and the speed of sound is a function of temperature.
So this was basically an acoustic thermometer.
Q: What did you determine through that experiment?
A: This was a feasibility experiment. We determined that it is
possible to actually send sound very long distances in water and
receive it. There was a two-year multi-national follow-up study
between Monterey and Hawaii – the Ocean Monitoring Project
- where Monterey was one node and the Scripps Institute in San Diego,
Woods Hole in Boston and a location in France were other nodes.
Q: How did you end up here?
A: I was doing audio signal processing, but speech and audio coding
is my first love - and I wanted to get back into it because of the
activity in MP3, wireless devices and other new applications. DoCoMo
USA Labs was about seven months old when I found out about it; I
sent my resume and was asked to come in for an interview. So I came
and things worked out.
Q: You’re one of the original people, aren’t
you?
A: Yes.
Q: How is it here for you?
A: Great. I really like it here because I can work on things I
like, and I’m given the support and the freedom to do that.
We also collaborate a lot with Japan on joint projects.
Q: Which group are you in?
A: I’m in the Media Lab, working on the Hyperaudio component
of the Hypermedia project. There is also a Hypervideo component.
Q: How is your work going?
A: Very well. Over the past three years, we took the standard codecs
that exist today and improved on them. We developed codecs that
are compatible and interoperable with current technology, but with
better audio quality or lower processing delay.
Q: Can you tell me a little bit about what you feel is
your contribution to the to the overall team?
A: I guess my main contribution is to identify important research
problems in my field - important in the sense that they will contribute
to future products; and to some important fundamental research.
Identify those few really good problems that we can address with
the finite resources we have, we have to select the right problems;
otherwise, we can’t really make any progress. We can’t
just work on everything and anything.
Q: What is your vision for the future?
A: DoCoMo Labs has a vision of 2010, which is 4G technology used
in ubiquitous communications across heterogeneous devices, networks
and media. I share that mission and am committed to that vision.
Q: As we conclude our interview today, I was wondering
if you have a favoritie quote?
A: “Whatever the human mind can conceive and believe, it
can achieve”
Napoleon Hill
Q: Thank you for your time today.
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