Intellectual Capital - William C.Y. Lee Looks Ahead to 4G Wireless

Posted: 03/2001

Intellectual Capital

William C.Y. Lee Looks Ahead to 4G Wireless
By Bruce Christian

Calling it a patched-up system that could be inefficient, William C.Y. Lee,
one of the world’s leading authorities on mobile communications, says it may be
best if the industry were to leapfrog over third-generation wireless and prepare
for the fourth-generation.

"I don’t like 3G," says Lee, chairman and chairman of the board for
LinkAir Communications Inc. (www.linkair.com).
"It is not a very good system. I feel it is wasting our time, and the
performance won’t be as we expected."

On the other hand, "4G technology can evolve quickly, so we can skip 3G
and go directly to 4G," Lee says.

For 35 years, Lee has worked on the technology side of wireless
communications. But he also recognizes the business side and the need for
resellers and agents to offer wireless communications.

"They have to get into wireless to survive," Lee says. "In the
future, portability and mobility will be vital to business and to personal
communications. If the distribution channels don’t get into wireless, I think
they are missing the boat."

Lee began exploring wireless communications after receiving his doctorate at
Ohio State University–writing his dissertation on satellite communications. He
was hired in 1964 at Bell Labs to further his satellite research with AT&T
Corp. (www.att.com). But before he arrived,
Congress cut funding to the AT&T project, because lawmakers feared the major
telecommunications company only would enhance its then monopolistic position. If
Lee wanted to work on satellite communications, he would have to go somewhere
else.

"I chose not to go," he recalls. He was then told of Bell Labs’ new
research department called AMPS, which would develop mobile communications. He
accepted the challenge, because he had never heard of mobile communications.

"Sometimes you don’t choose your future," Lee says. "But this
turned out to be a very rich field for me."

Indeed it has. Lee has written three books on wireless and more than 200
papers. He has taught at the university level and lectured throughout the world.
Lee’s latest book, Lee’s Essentials of Wireless Communications, was
released in mid-January. It is part of the McGraw-Hill (www.mcgraw-hill.com)
Telecommunications Series.

"Dr. Lee is among the elite telecom luminaries and has been a key player
in the evolution of wireless technologies from its first generation through its
current third generation," says Steve Chapman, executive editor at
McGraw-Hill.

After 15 years at Bell Labs, Lee went to work for the ITT Defense
Communications Division. Following his work there, Vodafone Airtouch plc (www.vodafone.com)–the
world’s largest mobile telecommunications company–hired him. His attention
turned to personal communications network (PCN) technology and, in 1989, the
United Kingdom granted Vodafone its PCN license.

Lee’s 1990 work developing a new microcell system increased radio capacity by
2.5 times over the conventional microcell system.

In all, Lee’s work has led to 25 U.S. patents, with 11 more pending. He also
was instrumental in conducting key research for Pacific Telesis Group’s (PacTel,
now part of SBC Communications Inc., www.sbc.com)
PCS experimental CDMA, which was perfected and launched in 1995 as a viable
commercial mobile technology.

When Lee speaks of 4G, his emotions are betrayed. He becomes excited. He says
the technology is a step beyond the immediate tomorrow.

He explains that the first three generations of wireless communications have
required using a pair of frequencies. One frequency is used to send out a
signal, a second one is used to receive.

"That is called the FDD [frequency division duplex]," Lee explains,
as if he has returned to City University of New York, where he taught the first
wireless classes offered there. "The first three generations use FDD
because they have no way to isolate the interference in the sending out and
receiving back in the cellular system.

"New scholars have come up with special smart codes that can isolate the
interference in the host cellular system, so you don’t need the FDD. Instead, we
can use TDD (time division duplex)."

According to Lee, this innovation allows a signal to be sent on one time slot
and return in another time slot on the same frequency.

"It’s really about spectrum efficiency," he says. "With this
system, you don’t need complicated technology."

Lee says much of the research done to make wireless better has been focused
on isolating interference.

"Interference is the killer. But now we have these special codes. We
don’t need any of the expensive technologies, like smart antennas," Lee
says. "This is simple, high-tech efficiency in using the spectrum, which is
very expensive."

Lee knows something about the cost of wireless. He remembers when the first
mobile system was available commercially in the United States. It was rolled out
just about the same time as the 1984 Los Angeles Olympics. The cost per unit was
$3,800.

"All the Wall Street analysts were saying it was too expensive. They
didn’t think there would be many people who would want it."

The Wall Street analysts were wrong.

"People like mobility," Lee said. "People like to travel.
California [residents] came to mobile quickly, because California likes to try
new stuff."

Of course, Lee agrees with the industry analysts who say that the future for
mobile communications is in data. It is another reason he is such a big
proponent of 4G.

"Since the Internet has come up and data transmission has started, we
need more bandwidth, and more capacity and now more frequency," Lee
explains.

That is why using the available frequency more efficiently makes more sense,
he adds.

"Sometimes you may be downloading very heavy traffic, but you may only
be sending back an acknowledgement or a request, so we don’t need the FDD. You
should be able to use the single frequency."

Bruce Christian is editor of PHONE+ magazine