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The Wireless World

  • August 27, 2002
  • By Prentice Hall
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Globalization

Movies like to show the hero using a cell phone aboard a jumbo jet or underneath the desert in Iraq. Both these scenarios will remain fiction for many years; it's still impossible to get a cell phone that will work everywhere in the continental United States, let alone the world. Only satellite systems achieve true global coverage, and they don't work indoors.

For world travelers, the best choice is probably GSM, but this is actually available in five different varieties. There are two versions of the American Digital AMPS (D-AMPS) system and two of cdmaOne, the Code Division Multiple Access (CDMA) cellular technology first developed by Qualcomm. Many phones support more than one version of a system, or even different systems, but it's important to make sure that the one you choose will work where you want to take it. In particular, American GSM uses different frequencies than does European GSM, and phones supporting both are still quite rare. The companies assume (probably rightly) that most people who buy a cell phone in Europe will never take it to America, and vice-versa.

Despite early hopes of a global standard, the incompatibility is set to continue into 3G. This is due partly to the commercial interests of rival companies, partly to the political machinations of national governments, and partly to genuine practical difficulties in making a new system compatible with older networks. Because 3G networks are initially limited to a few small areas, people want phones that can also be used with existing 2G networks. This affects the design of the 3G networks themselves, as it's easier to make dual-mode phones for systems that have something in common.

There is officially a worldwide standard for 3G, but it's really just a name ("IMT-2000"). It contains so many options that no phone or network will support them all. Three countries built 3G networks in 2001—Japan, Korea, and the Isle of Mann—and all used different systems. Whereas all European countries are building the same system, America will be a microcosm of the world: U.S. cellular operators are planning at least three different types of 3G, which may splinter into even more.

There is greater hope for worldwide standards in shorter range wireless systems, which are already replacing wires as a means of connecting computers together and may form the basis of 4G mobile. Wireless LANs based on the Institute of Electrical and Electronics Engineers (IEEE) standard 802.11 (Wi-Fi) system can be used nearly everywhere, as can the emerging Bluetooth technology. These really will enable a phone or a computer to communicate anywhere in the world.

WEB RESOURCES
www.s3.kth.se/radio/4GW/
The Personal Computing and Communication research group at Sweden's Royal Institute of Technology is trying to develop a 4G mobile system for the year 2010 onward. Its site has lots of interesting papers covering different possible directions that mobile communications could take in the future and a free 100-page report (in PDF format) called Telecom Scenarios 2010.

www.bt.com/bttj/
British Telecom publishes the quarterly BT Technology Journal, a combination of in-depth tutorials on 3G technology and futurology covering the wider applications of 4G.

www.wirelessweek.com
The trade magazine Wireless Week publishes most of its daily news stories online and has a huge archive of information about the cellular industry.

www.wirelessdevnet.com/
The Wireless Developer Network is a news and analysis site that covers every aspect of the wireless industry from the perspective of programmers and Web designers.

www.thefeature.com
The Feature is an online magazine about wireless technology and its applications. The site is run by Nokia, so its analysis is hardly objective, but it can still be interesting.

www.unstrung.com
Unstrung is an online magazine featuring daily news and analysis of wireless technology, applications, and business.


BIBLIOGRAPHY
Gralla, Preston. How Wireless Works. Que, 2001.
A picture book illustrating many aspects of wireless communications in full-page spreads and describing them in a very simple, nontechnical way.

Stetz, Penelope. The Cell Phone Handbook. Aegis, 1999.
A consumer-oriented guide to cell phones and service plans, teaching people how to avoid getting ripped off by slick salesmen and small print.

Webb, William. The Future of Wireless Communications. Artech House, 2001.
An exploration of how wireless communications might develop over the next 20 years, with a look at 4G and beyond. The author is much less optimistic (i.e., more likely to be right) than the companies touting virtual reality and direct brain links.

SUMMARY

  • The Web is going wireless. By 2003, more people will access the Internet via mobile phones than through computers.
  • Most existing mobile phone systems are 2G. New 3G terminals will support higher-speed data services. Further in the future, 4G may enable true mobile broadband.
  • Short-range wireless LANs and longer range cellular systems are fundamentally different, but can be used for similar applications. They are both competing and complementary.

This is a sample chapter of The Essential Guide to Wireless Communications Applications: From Cellular Systems to Wi-Fi, Second Edition (ISBN: 0-13-009718-7). For the full text, visit http://www.phptr.com

©2002 Pearson Education. All Rights Reserved.

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