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In many parts of the world, mobile
phones have become such a part of everyday life one wonders how we ever managed
without them. For world travelers, mobile phones can offer some
incredible benefits. However, they also present certain challenges, not
the least of which is whether they will even work when traveling from one place
to another.
Why Mobile Phones
are helpful
Along with the
obvious convenience and quick access to help in emergencies big and small,
mobile phones can be both economical and essential for travelers trying to stay
connected. An example: it's not uncommon for mobile calls to be cheaper
than local calls made from some hotel rooms. European hotels in particular
are known for excessive phone tariffs -- three days of connecting locally at a
five-star hotel in Amsterdam once cost me more than $100! However,
Europeans have no lock on this practice -- I recently stayed at a hotel in
Quito, Ecuador where local calls cost USD$.50 a minute! In contrast, many
mobile providers offer exceptional plans that include generous amounts of air
time, no long distance charges, and in some cases very reasonable international
roaming rates.
In other situations, a mobile
phone may simply be the only way to get online. This was the case
when I stayed at a lovely historic hotel in Krakow's old town --
unfortunately, the ancient phone lines were too noisy to allow a modem
connection at any speed. However, thanks to a GSM phone and
modem, I could connect with ease at 9600 bps -- good enough for e-mail.
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Checking e-mail with a GSM mobile phone
and
PDA aboard
a train in Denmark.
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Why Mobile Phones can be a
challenge
Mobile phone usage for the traveler
can sometimes be a bewildering affair. This is due to the preponderance of
various differing -- and incompatible -- mobile systems, often delineating
entire continents or regions. The main systems in use are outlined
below. The purpose of this discussion is not to delve much into the
technical aspects of each system -- that sort of thing can easily be found
elsewhere on the web. Rather, here we'll focus more on where these systems
are used and factors important to travelers.
| GSM - Global System for
Mobiletelephones One of the few mobile phone standards with a
self-explanatory name that is actually more or less accurate. It's the
closest thing there is to an "international" standard -- GSM systems
are used in nearly 200 countries (with 600 million subscribers) worldwide, from Europe (where the standard
originated) throughout Africa, Asia and Australia. Coverage in these areas
is for the most part excellent; in some cities the use of picocells even
makes it possible to use phones on moving subway trains. Though a latecomer to North
America, GSM is now making some substantial gains there, though with a different
flavor than used elsewhere. Originally utilizing the 900 Mhz spectrum, GSM
providers in parts of Europe, Africa, and Asia later added additional capacity
at 1800 Mhz. In North America, however, GSM service is currently available only at
1900 Mhz. The good news for world travelers is that most cell phone
manufacturers offer dual-band (900 and 1900 Mhz) or tri-band (900, 1800
and 1900 Mhz) phones that will work in most places GSM systems are found.
The bad news is that a fourth GSM system -- GSM 800, operating at 850 Mhz
-- may soon join the fray in the US. I'm only aware of one
"quad-band" (GSM 800, 900, 1800, 1900) phone so far, but if the
standard achieves widespread use I'm sure we'll see more.
While growing rapidly, in the US and Canada GSM service can be
scarce outside of larger urban areas. In Latin America, coverage currently
exists only in parts of Argentina, Bolivia, Chile, El Salvador, Paraguay and Peru
(all at GSM 1900) along with Venezuela (GSM 900) and Brazil (GSM 1800). Other notable non-GSM countries include South Korea
and Japan. GSM is a feature-rich technology that includes fax capability
and SMS (short messaging service). Most providers offer e-mail to
SMS gateways, making it possible to receive flight updates and breaking
news alerts over the phone. Many providers also offer quick connect
data services through ISDN lines, and the latest generation GPRS (Global
Packet Radio Service) promises high-speed "always on" data
connections much faster than the traditional 9600 bps. If you can't
tell, I'm a big fan of GSM and hope that it soon is available
everywhere. My principal mobile phone is a tri-band
"world" phone with service from T-Mobile, one of the largest
GSM providers in the US with roaming agreements with GSM carriers
worldwide . |

Example of tri-band GSM "World"
Phone
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AMPS - Advanced Mobile Phone
System At one time, this system might well have been
"advanced" compared to earlier methods. The original 800 Mhz
analog cellular system introduced in North America in the early 1980s, now it's
pretty much technically obsolete. However, even though it's been replaced
by newer digital technology, in some rural areas from the US to Australia to
Turkmenistan, it still might be the only mobile signal to be had. I often
carry a pre-paid AMPS phone as a backup for non GSM-areas. An enhanced
version called N-AMPS (Narrowband AMPS) offers some digital phone-like features
such as text messaging. Most of the US now uses E-AMPS, for enhanced
AMPS. Every country in the Western Hemisphere has 800 AMPS service,
as well as American Samoa, Angola, China, South Korea, Lebanon, Nauru, Northern
Mariana Islands, Solomon Islands, Turkmenistan, Uzbekistan, and Western Samoa.
D-AMPS - The first
digital version of AMPS, also using the 800 Mhz spectrum. Still used
(though not widely) in certain countries including Bolivia, Brazil, Canada, El
Salvador, Israel, Malaysia, Myanmar, Panama, Russia, Ukraine, Uzbekistan, and
Vietnam.
TACS - Total Access Communications
Service The original European 900 Mhz analog system launched in 1985
by Vodafone. Still used in Austria, Azerbaijan, Bahrain,
Cambodia, China, Democratic Republic of Congo, Gambia, Ghana, Hungary,
Ireland, Italy, Japan, Kenya, Kuwait, Malaysia, Mauritius, Nigeria, the
Philippines, Singapore, Spain, Sri Lanka, Tanzania, United Arab Emirates, United
Kingdom, and Yemen. Uses a protocol known as Frequency Division Multiple
Access (FDMA). Variations include ETACS (Extended TACS), ITACS
(International TACS), IETACS (International Extended TACS, NTACS (Narrowband
TACS and JTACS (Japan TACS).
NMT - An analog rival to
AMPS and TACS that uses 450 and 900 Mhz spectrum. Still used in most parts
of Europe and Asia, including Algeria, Andorra, Bangladesh, Belarus, Bulgaria,
Cambodia, Croatia, Cyprus, the Czech Republic, Estonia, the Faeroes,
Finland, France, Greenland, Hungary, Indonesia, Latvia, Lithuania, Malaysia,
Morocco, Norway, Oman, Poland, Romania, Russia, Saudi Arabia, Singapore,
Slovakia, Slovenia, Spain, Swaziland, Sweden, Thailand, Tunisia, Turkey, Ukraine
and Uzbekistan. Now that GSM is so widespread, some countries may be
planning to halt NMT service. In Finland, for example,
NMT900 service was shut down in early 2000; NMT450 service will be
discontinued at the end of 2002.
TDMA - Time Division Multiple
Access The first digital network widely used in the Americas, this is
the system which at one time was and still is the core of major US wireless
networks like Verizon, AT&T and Cingular. (Of these, however, AT&T
and Cingular are now converting some US bandwidth to GSM 1900. They may
also use the newer GSM 800, which operates at 850Mhz). Outside
the US, TDMA networks can be found in Argentina, Aruba, Bahamas, Belize,
Bermuda, Bolivia, Brazil, Canada, Cayman Islands, Chile, China (including Hong
Kong), Colombia, Costa Rica, Ecuador, Guam, Indonesia, Israel, Malaysia, Mexico,
New Zealand, Panama, Peru, Russia, St. Maarten, Suriname, Uzbekistan and
Venezuela. Some industry analysts are forecasting that the increasing
growth of GSM and CDMA in the Americas will eventually signal the end of TDMA.
CDMA - Code Division Multiple
Access A rival to TDMA in the Americas, this standard was developed by
QualComm, from which providers must license its use. CDMA carriers
in the US include Sprint PCS (which oddly enough started as a GSM carrier),
Alltel, and Verizon. There are now CDMA
networks elsewhere in the world, including Argentina, Australia, Canada, Chile,
Hong Kong, El Salvador, Guatemala, Israel, South Korea, Peru, Russia, Venezuela
and Zambia. This offers some
international roaming capability, though nothing like the near-global coverage available
from GSM carriers. In the purest technical sense, CDMA is more efficient
than GSM. In actual application, GSM has such widespread following and
rich features to keep CDMA from being much of a threat. However, it's
entirely possible that CDMA will contribute to the eventual demise of TDMA in
the Americas, though that time is likely to be many years away for the US and
Canada, and much longer for Latin America.
iDEN - (Integrated Dispatch
Enhanced Network) iDEN is essentially a hybrid of TDMA digital cell phone and
two-way radio. Providers are limited (examples are NEXTEL in the US and Amigo in
Israel). Phone equipment is produced exclusively by
Motorola, the company that created the standard by blending their historic
experience with handheld radios with the expertise in cellular technology. Certain iDEN phones offer GSM 900
compatibility, making global roaming possible in many countries without iDEN
networks.
PDC - Personal Digital
Cellular Behind GSM and D-AMPS, the world's mostly widely used digital system,
though its use is limited to Japan.
PHS - Personal Handyphone
System A newer Japanese standard especially designed for high-speed
data transmission up to 32 Kbps. Some installations may also be found in
parts of China, Thailand and Taiwan.
For more information about
systems and providers in specific countries, I highly recommend the
world cellular reference page at Teletechnics
Mobile Systems.
Satellite Phones
Whether you're posting a breaking
news story from the mountains of Afghanistan or just staying in touch with the
office during a Caribbean cruise, satellite phones can be the only choice when
you absolutely, positively need a phone in the far reaches of the
world. Satellite
phones can be expensive, though
Iridium's $1.50 USD charge is sometimes equaled or surpassed by international mobile roaming
rates for some GSM carriers. However, only recently have they achieved acceptable speeds
for data transmission.
Since there needs to be a clear line of sight
between the antenna and satellite, performance can also be affected by poor
weather and use is generally restricted to outdoors (though they will
sometimes work through glass or canvas). This can also limit the
ability to receive incoming calls, though for applications on boats and
other places an external antenna can greatly enhance their use.
Also, phones like Qualcomm's
GSP1600 (shown at right) offer compatibility with existing AMPS and CDMA networks to help
alleviate some of these drawbacks while allowing users to stay connected well
beyond the reach of lowly terrestrial networks. Users of the Thuraya
system serving Europe,
North & Central Africa, the Middle East, Central Asia and the Indian
Subcontinent
can also access local GSM networks in those areas. Also, external
antenna connections can help overcome some of the limitations to indoor
usage.
Satellite phone systems are
expensive to build and far less competitive than conventional mobile systems, so
there are only a few providers to choose from like Iridium, Globalstar,
Inmarsat and the previously mentioned Thuraya. Great strides have
been made in making these phones increasingly portable, though briefcase
models are still available and just about all of them need an oversized
antenna.
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Satellite
phone |
More to Come
This has been a general overview of
mobile phone systems used around the world. I will soon add to the information here with specific tips travelers can use when
selecting mobile phone service and options on how to best stay in touch with
mobile service while connecting internationally. Please come back soon.
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