GPRS Lengthy Delays>
Lengthy Delays Plague GPRS
Overheating GPRS terminals cause vendors to drastically decrease
speeds.
Andrew Dornan, Data Communications
All over the Telecom 99 show, vendors are proclaiming that general packet radio service (GPRS)--a
big step towards third-generation (3G) wireless networks--is ready to roll. Ready to roll, it may be.
But ready to use, it is not.
The problem? Vendors have run into difficulties developing GPRS terminals. GPRS equipment to
build networks exists; vendors are right about that. But carriers won't be able to offer GPRS services
until the terminals arrive.
Right now, some vendors have prototype GPRS terminals that are being used in trials. In the eyes
of the GSM Association (Dublin), that means everything is on schedule, according to association
chairman Michael Stocks. "The terminals are here," Stocks told the Show Daily.
The vendors themselves tell a different story. "It will be at least a year before we are selling GPRS
phones," says Juha Junnonen, a mobile marketing manager at Nokia OY (Espoo, Finland). Alcatel
N.V. (Paris) says the same thing: "We won't be selling GPRS phones until Q3 2000," admits Ivan
Gouletquer, a GPRS demonstrator from Alcatel. "Neither will anyone else."
Nokia's GPRS demonstration at the show uses wireless local area network (LAN) cards, not GPRS
cards, for the actual radio interface. Ericsson LM (Stockholm, Sweden) hasn't even brought any
prototypes, preferring to show off its nonfunctioning "concept" 3G phones. Both of them--and
Motorola Inc. (Schaumburg, Ill.)--quote the second half of next year as their GPRS shipping target.
The delays are only half the problem. When GPRS terminals do finally arrive in the shops,
customers will find another disappointment: the phones and PC cards won't allow speeds anything
close to the 115 kbit/s so often touted by vendors.
Alcatel is one of the only vendors to have a working prototype GPRS phone at the show, and guess
its speed? A mere 14.4 kbit/s, no better than the bandwidth available using conventional
circuit-switched global system for mobile communication (GSM).
To make things even worse, the first GPRS terminals will only handle asymmetrical traffic. Nokia's
first GPRS card will only run at 14.4 kbit/s upstream--the same as GSM--and 43.2 kbit/s
downstream. Alcatel says the same thing about its GPRS phone, and Ericsson won't even put a
figure on speeds.
Panasonic Matsushita Co. (Yokohama, Japan) has announced a GPRS terminal that will handle 56
kbit/s in each direction, but right now, it's just an announcement. A mock-up of it is on display at
the Japan Pavilion. But potential customers face an even longer wait. "It should be available by
Christmas," says Hiroshi Tamano, associate director of sales and marketing at Panasonic. "That's
Christmas next year."
What's the fundamental problem? Cellular terminals transmit using microwaves, which, like the
radiation used in a microwave oven, produce heat. The more time slots the terminal uses to
transmit, the hotter it gets. And because GPRS is always switched on, it continuously gives off
heat, unlike GSM phones, which only transmit very short messages to tell the base station where
they are. Wasting energy as heat also shortens battery life: Power consumption rises almost
proportionately to bandwidth.
Vendors are trying to find a way to focus the transmissions out of the equipment so that less is
used to cook the cards, but until then, the maximum bandwidth is about 20 kbit/s upstream and 40
kbit/s downstream, according to experts.
GSM Association chairman Stocks plays down the difficulties in tackling these problems. "It's a
challenge, not a crisis," he asserts. He maintains that GPRS terminals capable of handling
bidirectional 115 kbit/s will be available next year, but admits that he's not familiar with the technical
challenges faced by vendors.
The delays in rolling out GPRS terminals are likely to have some additional effects. In particular,
Wireless Application Protocol (WAP) will let service providers offer Internet access via mobile
phones, needs a packet-based technology such as GPRS to work effectively. WAP can be used
over today's circuit-switched mobile networks, but takes a long time to set up a call: Nokia, whose
first WAP phone has just shipped, is quoting a call setup time of up to 40 seconds. And
downloading Web sites at 14.4 kbit/s can be tedious.
All the same, GPRS promises to be well worth the wait. Higher bandwidths are only one of its
attractions. Other pluses include being "always on," eliminating the lengthy call set up times. In
addition, GPRS services promise to be low cost, because the data is carried over otherwise-unused
bandwidth.
While GPRS is on hold until terminals arrive, some users wanting higher-bandwidth mobile data
have another option: high-speed circuit-switched data (HSCSD), which enables users to set up
multiple parallel calls and then combine them together. The main problem with HSCSD, however, is
that users have to pay for multiple calls and suffer lengthy setup delays. Still, commercial HSCSD
terminals exist. One of the first, Nokia's HSCSD card, the CardPhone 2.0, offers 42.3 kbit/s
downstream and 28.8 kbit/s downstream, but calls still take up to 40 seconds to set up.
Peter Heywood contributed to this report
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