Paradigm Shift>
Mobile World Leader
GSM heads the pack as the most favored digital wireless standard, and
seems likely to do so for the next generation
Sarah Parkes, Contributing Writer
In the world of mobile, no technology can boast the widespread success of global system for mobile
communication (GSM), the digital cellular standard now used in more than 133 countries around the
world. GSM is by far the favored technology in Europe, which boasted an estimated 95 million
subscribers by the end of last year. It has also seized the lead in Asia and Africa, and is now
making inroads in the previously resistant markets of the Americas.
According to the GSM Association (Dublin), more than 140 million people around the world used
GSM networks last year, representing more than 60 percent of the world market for digital wireless.
That figure is expected to balloon to as many as 230 million by year's end.
Until now, cellular technology has been mostly about providing voice connectivity to keep people in
touch while on themove. But the emergence of new data-based applications, from home
management networks to interactive television, multimedia-based news and online shopping,
promise to make data king of the world's landline and wireless networks by 2005.
Upping the Ante
To ready GSM for the imminent launch of new mobile services such as Web access, a number of
data-oriented enhancements are already in the pipeline. High-speed circuit-switched data (HSCSD)
technology, for example, bumps up GSM's sluggish 9.6-kbit/s data rate to as much as 57.4 kbit/s
by making use of up to four time slots in GSM's time-division multiple access (TDMA) structure.
Easy and relatively cheap to implement, HSCSD provides a quick-fix boost but has the
disadvantage of being both spectrum-inefficient and based on circuit-switched technology, which is
better suited to voice than to bursty data applications.
A better solution is general packet radio service (GPRS), which has the power to increase
transmission rates on GSM networks to 115 kbit/s. Based on packet-switching technology, GPRS
is cost-effective because it can cram large amounts of information into one time slot and, unlike
HSCSD, doesn't insist on keeping a channel open when there's no information to transmit.
The downside: The move from circuit- to packet-based technology entails an investment of around
$150 million for a wireless network. Dominique Strowbridge, technology marketing manager at
Motorola in the United Kingdom, says that while the infrastructure investment is indeed
considerable, operators need to upgrade to GPRS to preserve future competitiveness. "It's the
stepping stone to the future," he says. "Third-generation is going to be based around data
capabilities, so moving to GPRS now will provide significant long-term benefits."
On the Edge
While HSCSD and GPRS provide stopgap solutions for offering high-bandwidth applications over a
technology originally designed for carrying voice, third-generation (3G) systems and Enhanced Data
Rates for GSM Evolution (EDGE) systems will open the floodgates to high-speed data streams.
EDGE makes use of a special modulation scheme to increase the data transmission rates for a
GSM 200-kHz carrier to as high as 384 kbit/s. Even better, the technology can be implemented on
second-generation as well as 3G systems, helping operators that missed out on a 3G license to
remain competitive.
L.M. Ericsson AB (Stockholm), a leading EDGE proponent, was one of the first to trial an EDGE
system. The company installed an experimental network at its research and development (R&D)
center in Montreal last year. Aside from testing wireless connectivity, Ericsson says its engineers
will evaluate the performance of Bluetooth, the wireless data system it is developing-along with other
emerging 3G technologies-with Nokia, Intel and others.
While data-rate enhancement technologies like EDGE will provide souped-up versions of standard
GSM, the real boost to wireless will come with the implementation of 3G systems, due as early as
2001. With data rates around 2 Mbit/s, next-generation GSM will deliver high-bandwidth multimedia
to new kinds of mobile devices that resemble a combination phone and PC.
"User demand for data-based applications will make the broadband services market worth $10 billion
by 2010," says Ragu Gurumurthy, a New York-based consultant with Booz Allen & Hamilton Inc.
(McLean, Va.). "We're looking at a penetration of 50 to 60 percent in the developed markets of
Western Europe, the U.S. and some countries in Asia-Pacific."
Gurumurthy says people soon will routinely use wireless technology to access the Internet and a
wide range of online services such as electronic news, interactive games and customized
information.
For the GSM vendor community, 3G inevitably means Universal Mobile Telecommunications
System (UMTS), the next-generation iteration of the GSM spec based on wideband code-division
multiple access (WCDMA) technology. Developed by the European Telecommunications Standards
Institute (ETSI, Sophia Antipolis, France), UMTS is twice as spectrum-efficient as GSM and
supports both circuit- and packet-switched transmission. That means increased network capacity
and the 2-Mbit/s data transmission speeds essential for smooth video, broadcast-quality multimedia
and high-speed Net cruising.
With standards for Phase 1 systems being finalized this year, UMTS-based networks are expected
to arrive in commercial services around 2002.
Then there's the Wireless Application Protocol (WAP), a new standard that's expected to be the
basis for a Web browser specifically for wireless devices: the microbrowser. Handset-makers
representing three quarters of the GSM equipment market and carriers representing 100 million
GSM subscribers, have pledged to roll out WAP-enabled handsets by the end of this year.
Paradigm Shift
The new technologies already pushing GSM bandwidth and the more advanced 3G systems just a
few years away will change the delivery of mobiles in the coming years, says Mike Short, a former
chairman of the GSM MoU (Memorandum of Understanding) Association and now director of
network strategy with BT Cellnet Ltd. (London). "The old mobile 3-C model of Coverage, Coverage
and Coverage is being replaced by a new 3-C paradigm-Capacity, Capability and Content," Short
says. Capacity means catering to a range of different usage patterns encompassing not just
geographical and time parameters but also voice and data profiles. Capability means 3G operators
will compete head-on with existing 2G and need to woo users with added features and higher
quality. Content, meanwhile, highlights the growing importance of Internet and personalized
information services.
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