Developing Wireless Technology Comes With Its Own Language

It’s a wireless world out there. Not only are cellular phones now routine, but some also are being used for
text messages, and wireless capabilities are being added to other devices, like personal digital assistants,
laptops and desktop computers.

by Walter S. Mossberg Wall St. Journal

Unfortunately, the ridiculous jargon associated with wireless technology is spreading even faster than the
technology itself. You can’t read an article or hear a talk about wireless communications without
encountering dense terminology like GSM, Bluetooth, 3G and 802.11b.

So here’s a primer for wading through this jargon. I’ve tried to write it in plain English, which means techies
will find it insufficiently detailed, but I hope it will help everyone else.

First, let’s tackle the acronyms that describe the current wireless phone systems, which are mainly
designed to handle voice, not data.

• GSM: This stands for global system for mobile communications, and is the standard transmission and
reception technology used for wireless phones in Europe and much of the rest of the world outside the U.S.
Most countries, logically, decided to pick a single, standard wireless phone technology years ago, and they
settled on GSM. The U.S., incredibly, refused to settle on a standard and that blunder has resulted in a
patchwork of multiple, incompatible technologies. The result has been better and more innovative wireless
phones and wireless services in Europe than in the U.S.
GSM exists in the U.S., and is gaining ground here, though it is broadcast on a different frequency than the
system used in Europe. It is used by companies including VoiceStream, Cingular and AT&T, which is in the
process of converting its network to GSM.

• CDMA: The most widespread of the three main wireless phone technologies used in the U.S., it stands for
code-division multiple access, and is the system used by Verizon and Sprint.

• TDMA: This stands for time-division multiple access, and is the third of the three major U.S. wireless
technologies. It has been mainly used by AT&T, which is abandoning it for GSM.

These are the current systems in the U.S. The following terms, describing future technologies, have a lot
more hype surrounding them.

• 3G: This is the Holy Grail of wireless systems, a new "third-generation" standard that supposedly allows for
high-speed, always-on data transmission and reception. It promises to handle e-mail, instant messaging and
Web browsing as smoothly as current wired technologies. It is supposed to be able to transmit data at
speeds up to two megabits a second — faster than most home DSL and cable-modem connections. But
many 3G tests have been disappointing, and phone carriers are having trouble getting it off the ground.

• 2.5G: This is an interim step toward 3G, and is arriving in the U.S. this year. It supposedly gets peak data
speeds of 144 kilobits per second, more than double the speed of a home dial-up modem and much faster
than the data speed of about 10 kbps achieved by current wireless phones. But most users, most of the
time, will see much lower speeds of around 50 kbps, which is about as fast as a home dial-up modem.

• GPRS: This is the name for the 2.5G system that will work on GSM phone networks. It stands for general
packet radio service.

• 1xRTT: Sometimes known as CDMA2000 1x, this is the CDMA operators’ 2.5G technology — their answer
to GPRS.

These wireless technologies are all for wide-area networks, like cellphone systems, that must stretch for
miles. But there are two very important local-area, or short-range, wireless technologies that are already here
and are likely to become more common and vital in coming years.

• Wi-Fi: This is one of the two, a wireless networking technology for PCs and PDAs that allows multiple
devices to share a single high-speed Internet connection over a distance of about 300 feet. It can also be
used to network a group of PCs without wires. Wi-Fi is spreading like wildfire in homes, offices and public
places such as Starbucks coffee shops, hotels and airports.
If you walk into one of these Wi-Fi-equipped places with a properly equipped PC or PDA, you can quickly be
on the Internet at true broadband speeds, as if you were connected by wire to a DSL line or cable modem.
Wi-Fi is very fast. It can transmit data at speeds of up to 11 megabits per second.

• Wi-Fi 5: A new version of Wi-Fi that’s even faster, with a maximum speed of 54 megabits per second.

• 802.11b: The old techie name for Wi-Fi. (The techie name for the new Wi-Fi 5 is 802.11a.)

• Bluetooth: The other short-range wireless technology; it replaces cables over very short distances —
roughly 30 feet or less. Bluetooth, slower than Wi-Fi at about one megabit per second, is designed to link a
cellphone to a laptop, or a PDA to a cellphone, or a laptop to a printer — all without cables.

Write to Walter S. Mossberg at [email protected]

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