Viterbi honored
rcrnews.com
Viterbi's math genius ahead of its time
By Lynnette Luna
Dr. Andrew Viterbi knows that
innovative technology isn't an easy
sell.
Perhaps the former Qualcomm Inc.
vice chairman was scientifically a
bit ahead of his time. At any rate,
Viterbi got his message across.
Considered one of the most brilliant
mathematicians in the wireless
industry, Viterbi is a primary
mathematical genius behind CDMA
technology, the world's fastest-growing mobile-phone
technology, poised to appear in some form in virtually
all third-generation wireless systems. And the Viterbi
Algorithm is not only used in all digital and satellite
networks for interference suppression, but medical
scientists are using his mathematical invention to
research DNA. Textbooks today make mention of the
formula.
It was in the late 1980s when Viterbi, Dr. Irwin Mark
Jacobs and a group of Qualcomm scientists began
studying the prospect of using a military-based
spread-spectrum technology called Code Division
Multiple Access. The complex technology, which relied
on many statistical estimates to work properly, was not
an easy sell to a U.S. wireless industry that had locked
down rival Time Division Multiple Access technology as
the new digital standard.
"I don't think it would have taken off if we didn't have
the reputation that we did," reflected Viterbi. "There
was quite a debate, and in order to win that debate you
had to know what the parameters were and do a lot of
analytical work. That's my strength. I worked on that."
Viterbi had built up his reputation for 30 years when he
and Jacobs approached the industry with CDMA
technology. His experience with spread-spectrum
technology began in 1957 as a member of a team that
designed and implemented the telemetry equipment of
the first successful U.S. satellite, Explorer I, in the
Communications Research Section of the California
Institute of Technology Jet Propulsion laboratory.
By 1967, Viterbi and Jacobs had co-founded Linkabit.
There, they studied and developed applications for
spread-spectrum technology, selling military electronics,
including spread-spectrum modems used by the Air
Force and B-52 fleets. MA/COM bought the company in
1980, giving Linkabit enough capital to begin looking at
commercial applications for spread-spectrum
technology. The company began building VSAT
terminals. Hughes eventually bought that business,
making $1 billion in revenues a year. The two scientists
started Qualcomm in 1985, and applied
spread-spectrum technology to mobile data services via
VSAT terminals. That business is known as OmniTracs.
Qualcomm today has licensed the technology to more
than 300,000 trucks.
"That was a bit of a struggle, demonstrating that you
could process more mobile data with very small aperture
antennas," said Viterbi. "The FCC also said we could use
small dishes as long as they didn't interfere with other
services. Our license was conditional, and we'd be off
the air if we interfered. We solved that problem with
spread spectrum."
Though Viterbi and Jacobs had established their
reputations as spread-spectrum experts, CDMA
technology was no easy sell. It was mathematically
confusing, and many doubted the capacity claims
Qualcomm said the technology could provide compared
with analog networks when the system was loaded with
users.
"Gradually, by not only talking, but demonstrating and
doing some elaborate show-and-tells, we were able to
convince more and more of the industry," said Viterbi.
"The technologists were more familiar with the concept.
Getting to the decision-makers took a little more effort.
It took a lot of presentations. I made my share.
Gradually, I'd say that at the CDMA World Congress
every year, the audience got bigger and the reception
was warmer."
By the early 1990s, the fundamentals of CDMA
technology were sound. Viterbi had figured out the
underlying mathematics to CDMA technology in a 1991
white paper. He also was a contributor to the 1995
book, CDMA Principals, which further strengthened the
standard's technological foundation.
"I'd be the first to stress that had it not been for the
demonstrations and the clever ideas that came from the
theory, that others are more responsible for than I,
CDMA would not have taken off," said Viterbi. "It was a
team effort, and I'm proud of the part I played."
Viterbi was no stranger to hostile receptions prior to
CDMA technology's acceptance. Nearly 30 years before,
he had developed the Viterbi Algorithm, a mathematical
equation considered far too complex for 1966. Today it
is used in all wireless systems and most digital satellite
communication systems, both for business applications
and for direct satellite broadcast to the home.
"The interesting story there was that it was initially
considered far too complex, which resonates what
happened to CDMA. We didn't have an enabling
technology," Viterbi recalled of his efforts to educate
the communications industry of the mathematical
equation. "I would talk about 1,000 memory registers to
implement and people would leave the room. Moore's
law has made things a lot easier to do."
The scientist has received numerous awards and
recognition for his leadership and substantial
contributions to the communications industry over the
years. He has received honorary doctorates from
universities in Canada, Italy and Israel and has been
granted numerous awards in Japan, Germany, Italy and
the United States. Today, he's a member of the U.S.
President's Information Technology Advisory Committee.
He's most proud of the advancement of the Viterbi
Algorithm.
"Certainly the Viterbi Algorithm is a source of
considerable pride, not only for what it did in wireless,
but it's used in other applications like voice recognition
and most amazing to me, it's become popular in
molecular biology," said Viterbi.
These days, the 65-year-old Viterbi is anything but
retired. Though earlier this year he ended his stint as
vice chairman with Qualcomm, now only serving on the
board, he's serving on a half a dozen boards of other
companies, including technology start-ups and venture
funds, and keeping up with professional activities that
include speaking at various conferences and colleges.
Today, he's trying to set up office in San Diego and is
looking for an administrative assistant. "I haven't had a
chance to lie on the beach yet," he joked. |
