Next-Generation Wireless: No Panacea
Think the cellular providers will surely learn from their current quagmire? Think again.
October 16, 2000
Judging from the money, effort–and hype–expended for its development,
the third generation (3G) of wireless services due to roll out around the
world later this year should usher in an era of go-anywhere, do-anything
communications. Third-generation (analog is cellular's first generation;
current digital systems are the second; and future high-speed digital wireless
will be the third) wireless systems will transmit data at hundreds to thousands
of kilobits per second–far faster than the standard 9.6kbps wireless modems
in use today. Technology optimists gush about the possibilities of instant-response
mobile Web browsing, full-motion video cell phones, and viewing movie trailers
over 3G portable devices.
It's far more likely, however, that future global 3G networks will be
as fragmented and incompatible–i.e., as confusing and frustrating for users–as
today's cellular networks. In particular, one of the most critical features
of wireless communications–roaming, or the ability to use a device outside
of one's home network or country–will remain a headache for some time to
come.
The main reason: Any future global wireless infrastructure has to evolve
from today's hodgepodge of competing and incompatible wireless networks,
a process tremendously complicated by the strategies and maneuvers of manufacturers
and operators with vested interests in one system or another. And while
last year's International Telecommunication Union deal (ITU) established
a specification that would supposedly "harmonize" future wireless systems
globally, it also left plenty of room for disharmony. "The goal was to
converge on one standard, and that's not going to happen for a long time,
if ever," says Peter Rysavy, president of Rysavy Research, a wireless-industry
consultancy in Hood River, Ore.
Valiant attempts
The ITU specification, dubbed IMT-2000 (for international mobile
telecommunications) established outlines for future 3G systems. Among other
things, it called for them to support wireless data transmission rates
of at least 2 megabits per second for indoor fixed terminals, 384 kilobits
per second for outdoor terminals at walking speed, and 144kbps at driving
speed. The specification represented a valiant attempt to resolve an acrimonious
struggle between major factions that had seen lawsuits between large European
and U.S. manufacturers, and even U.S. government intervention.
At issue were the details of the proposed air interface (the method
of packaging data for wireless transmission and reception) known as code
division multiple access, or CDMA. U.S. CDMA pioneer Qualcomm
and its partners stood behind a version called cdma2000, which is based
on the second-generation (2G) system currently used by such cellular operators
as Sprint and Verizon in the U.S. and DDI and IDO in Japan. Although it succeeded in bringing the two standards closer technically,
the ITU was unable to get the sides to agree completely. As a result, it
was forced to leave the actual choice of air interface for 3G systems optional,
as long as it met the stated performance requirements–and to put the best
face on the lack of true standardization by calling it harmonization.
Back door plan
The lack of a specific air interface standard also left the door
open for a third major approach to 3G wireless systems. Led by AT&T,
operators using TDMA (time division multiple access, the 2G system most
widely used in North and South America), are pinning their hopes on a technology
called EDGE (enhanced data rate for global evolution), another high-speed
technology that the ITU has accepted as meeting 3G performance requirements.
Because it is compatible with existing TDMA networks, EDGE doesn't require
TDMA operators to install all-new network radio equipment as they would
have to with the CDMA-based 3G options.
With three major systems in the works, users will face choices in 3G
wireless services as difficult as they do in today's cellular market. Adding
to the confusion will be the variety of interim technologies operators
can use to get from today's low data speed systems to the fastest 3G networks.
Current users of 2G CDMA networks–such as Sprint and Verizon customers–have
the simplest choices. Their operators can offer increasingly speedy data
transmission using technologies with names like 1X (in various versions)
and HDR (high data rate) that are all based on the same underlying technology,
eventually arriving at 3G cdma2000.
The simplicity comes with a trade-off, however. While such users will
have roaming capabilities on a fair number of other networks around the
world that use the same version of CDMA, those will be substantially outnumbered
by GSM networks. As a result, says Rysavy, "Countries that are picking
cdma2000 run the risk of ending up isolated islands in the worldwide cellular
situation."
Perry LaForge, executive director of the CDMA
Development Group (CDG), argues, however, that dual-mode phones–devices
able to communicate over two types of networks, such as future cdma2000
and W-CDMA systems–will allow the same kind of roaming many operators offer
today. Even with different versions of 3G CDMA being installed, he claims,
"You're talking about two similar technologies. You will be able to roam
across both as people do with AMPS (an analog cellular technology) and
CDMA today."
Complicated choices
That may be true once the entire world has migrated to full-fledged
W-CDMA or cdma2000 3G systems. But such migration won't happen smoothly,
and perhaps not at all, because of the more complicated choices facing
operators of the two other major types of systems, GSM and TDMA.
For example, users of GSM–which was developed through a remarkable cooperative
effort among European manufacturers, operators, and governments, and then
spread rapidly around the world mainly because it made roaming so effortless–will
get higher data speeds when their service providers upgrade to an interim
technology known as GPRS (general packet radio service, expected to begin
commercial service next year), and once more when they move to UMTS. The resulting situation will have at least two effects. First, it will
complicate future cdma2000 users' prospects for roaming across around the
world on UMTS networks using dual-mode handsets, because neither cdma2000
nor UMTS systems will be uniformly available. Second, it will cause future
users of networks based on UMTS, the chosen successor to GSM, similar problems
when traveling away from home–while they'll be able to access 2G services
everywhere there is a GSM network, 3G services requiring UMTS networks
will be less uniformly available.
Not free to roam
Users of future versions of GSM networks–those incorporating either
GPRS or UMTS–will for the most part face the same problems in the U.S.
as do current GSM users: in particular, a lack of networks providing roaming
capabilities. They may find partial relief, however, if their home operators
implement EDGE, which in addition to being a method of bringing high data
speeds to TDMA networks, is also a tool for giving them compatibility with
the GSM world. With EDGE-capable handsets, GSM users will have roaming
capability over any TDMA network that also uses EDGE.
It's unclear how much motivation GSM operators will have to implement
EDGE, however–the advantages to them are far less obvious than to TDMA
operators, while the disadvantages are greater. "We think EDGE will not
happen anywhere outside U.S.," says Jane Zweig, executive vice president
at market researcher Herschel Shosteck Associates. As GSM operators begin
building out GPRS and UMTS infrastructure, she notes, "money is limited,
and so are engineering resources. EDGE is not going to be at the top of
the list for investment."
If GSM operators in Europe and Asia decide not to implement EDGE, it
will inconvenience those regions' users wishing to use their phones in
the U.S. It will be far worse for U.S. TDMA users, however, which include
the customers of AT&T, BellSouth, and Southwestern Bell. For such customers,
who are by far the majority in the U.S., EDGE–which AT&T claims will
be available as soon as 2002–is not just the only route to higher-speed
data services, it also offers the only mid-term hopes for roaming outside
the U.S. If non-U.S. GSM operators don't adopt EDGE, such hopes are futile.
In the longer term, though, EDGE should make it possible for huge numbers
of U.S. TDMA customers to use their phones overseas for the first time.
That will happen, according to Jim Grams, vice president for technology
development at AT&T's wireless group, because manufacturers will develop
hybrid phones and other user devices capable of working with both EDGE
and UMTS networks. "UMTS and EDGE technologies are going to be quite complementary,"
he claims.
In the end, though, choice of technology is only the beginning of the
struggle for operators–and, by extension, for their customers. At least
as important, according to Herschel Shosteck's Zweig, is actually engineering
and building the physical network. "In most cases, when you look at the
2G digital stuff, it's never been question of what's a better technology,
it's a question of how is the network designed," she says. "And that determines
how successful they are." Alphabet Soup
A breakdown of the technologies, and our take on each.
ACRONYM: CDMA
ACRONYM: TDMA
ACRONYM: GSM
ACRONYM: GPRS
ACRONYM: EDGE
ACRONYM: W-CDMA
ACRONYM: cdma2000
ACRONYM: UMTS
Robert Poe(rpoe@business2.com)is
a Senior Writer for Business 2.0.
Illustration:
James O’Brien
WHAT IT STANDS FOR: Code division multiple access
WHAT IT DOES: Sends multiple signals, each containing a unique
code, and each spanning the same 1.25 Mhz frequency band. Receivers ignore
all signals except those that contain the code they are looking for. The
system significantly increases the amount of data that can be sent in a
given frequency range.
WHERE IT'S USED: As a second-generation system, currently used
by operators in the U.S. (including Sprint and Verizon), Korea, Japan,
Hong Kong, and other Asian markets.
WHO MANUFACTURES IT: Technology commercialized by Qualcomm;
manufactured by many companies, including Samsung, Ericsson, and Nokia.
PROGNOSIS: As a 2G technology (called IS-95 or cdmaOne), offers
better performance than other 2G systems. With a late start behind GSM
and TDMA, though, users are far outnumbered by those of GSM globally, and
of TDMA in U.S. But two of the three major 3G systems are based on CDMA,
so it will dominate in the future
WHAT IT STANDS FOR: Time division multiple access
WHAT IT DOES: Divides available spectrum into narrow frequency
bands, and each second into individual time slots. An individual transmission
uses one of the time slots for each second in one of the frequency bands.
Offers significantly more transmission capacity for a given frequency than
analog cellular.
WHERE IT'S USED: Used mostly in the United States by operators
such as AT&T, BellSouth, and Southwestern Bell
WHO MANUFACTURES IT: Most major manufacturers
PROGNOSIS: An outdated technology being kept alive indefinitely through
prodigious engineering and marketing efforts by AT&T and supporting
manufacturers
WHAT IT STANDS FOR: Global system for mobile communications
WHAT IT DOES: A standard based on TDMA technology, GSM was established
by Europe-wide agreement among manufacturers, operators and governments.
Became phenomenally successful because of the roaming and manufacturing
economies of scale it offered.
WHERE IT'S USED: Almost exclusively by operators in Europe,
at least one operator in most Asian markets, and several substantial operators
in the United States
WHO MANUFACTURES IT: Most major manufacturers, but especially
in Europe
PROGNOSIS: Along with its 3G evolution, likely to predominate
everywhere except in the U.S., where it will continue to play a modest
role in the face of fierce competition by technically superior CDMA
WHAT IT STANDS FOR: General packet radio service
WHAT IT DOES: Provides higher-speed data transmission for GSM
networks
WHERE IT'S USED: Commercial operation to begin early next year
WHO MANUFACTURES IT: Same as GSM operators
PROGNOSIS: Probably will be adopted by most GSM operators
WHAT IT STANDS FOR: Enhanced data rate for global (or GSM) evolution
WHAT IT DOES: Uses enhanced TDMA technology to achieve 3G data
transmission speeds; compatible with both GSM and U.S. TDMA networks
WHERE IT'S USED: Commercial introduction slated for 2002. Likely
to be widely used in the U.S., where it's the only high-speed data option
for TDMA operators. GSM operators in Europe and Asia may also adopt it,
but spending on GPRS and 3G equipment will be their first priority
WHO MANUFACTURES IT: Manufacturers of TDMA and GSM equipment
PROGNOSIS: Good in United States, iffy in Europe and Asia
WHAT IT STANDS FOR: Wideband CDMA
WHAT IT DOES: A high-speed version of CDMA, which is based on
Qualcomm technology, but significantly modified by Japanese and European
manufacturers
WHERE IT'S USED: The GSM world's chosen 3G technology
WHO MANUFACTURES IT: GSM manufacturers
PROGNOSIS: Will be the dominant 3G technology outside the U.S.,
less so in the U.S.
WHAT IT STANDS FOR: Commercial name for the version of 3G CDMA
based on 2G CDMA (IS-95/cdmaOne)
WHAT IT DOES: A high-speed version of CDMA compatible with existing
2G CDMA networks
WHERE IT'S USED: First commercial operation scheduled for later
this year in Korea; will be 3G technology for all 2G CDMA operators in
the U.S. (including Sprint and Verizon), Japan, Korea, and several other
Asian countries
WHO MANUFACTURES IT: Further development of earlier CDMA technology
by Qualcomm and its partners, manufactured by most major manufacturers
PROGNOSIS: Besides being a lock with 2G CDMA operators, may
entice new operators, particularly in Asia, away from GSM because of its
superior efficiency and call quality
WHAT IT STANDS FOR: Universal mobile telecommunications system
WHAT IT DOES: An overarching standard mainly based on W-CDMA
technology but also includes technologies for particular uses
WHERE IT'S USED: Same as W-CDMA
WHO MANUFACTURES IT: Same as W-CDMA
PROGNOSIS: Same as W-CDMA
Content copyright © 2000 Imagine Media Inc.