WCDMA (Wideband Code-Division Multiple Access)
Third-generation mobile telephony or 3G
networks such as WCDMA (Wideband Code-Division Multiple Access) and UMTS
(Universal Mobile Telephone System) allow for faster data transfer than GPRS
and EDGE, and also let you talk while you transfer data.
Advantages
of WCDMA
WCDMA technology gives you a faster data
connection in mobile networks: currently up to 384 kbps.. In future generations
of WCDMA technology, this may increase up to even 10 Mbps.
You can do all of the usual activities:
send SMS or MMS messages, download games and ringing tones, synchronize your
phone with your PC calendar or corporate intranet, and browse the Internet.
WCDMA is also fast enough for video streaming.
With GPRS or EDGE phones, you can't do
these things while talking. WCDMA is based on a different technology that lets
you hold simultaneous voice and data connections, so you can send images and
check your email while you're on the phone.
Like GPRS and EDGE, you're billed for data
transferred, not for time connected, so you can be connected just about all the
time.
Please check the availability of the 3G
service with your network operator and/or service provider.
How
WCDMA works
Wideband Code-Division Multiple Access is a
relatively new technology for accessing radio channels (where data is exchanged)
with mobile devices.
How it workks
For a quick explanation, let's first look
at a familiar radio scenario. FM radio stations are all assigned frequencies
(like 95.6, 102.1, and so on). Stations can have the same frequency as long as
there is sufficient distance between them. Have you ever been driving along,
listening to your FM radio, when two stations seem to be fighting for the same
frequency and you hear both? This happens when you're driving through an area
where two stations using the same (or close to the same) frequencies overlap
slightly.
Codes
help avoid confusion
Usually, cellular networks work in a
similar way. When you call someone, you're assigned a channel for the duration
of your call. When you send data over GPRS, your phone looks for an empty channel
to use. With WCDMA, voice calls and data connections are each assigned codes,
not specific frequency channels - hence the term "Code-Division Multiple
Access." The device on the receiving end knows the proper code, and
automatically filters out any data that isn't stamped with it. This method
frees a lot of space on the network that otherwise wouldn't be available, and
it adds security.
Wideband
makes data flow faster
Imagine pouring water out of a bottle. If
the bottleneck is narrow, you may have lots of water to pour but it's only
going to go as fast as the narrow opening will let it. This is where the
"Wideband" part of WCDMA comes in: it becomes more like pouring water
out of a vase. It's not that the individual water molecules (or bits of data)
move any faster, but much more can be transferred at any given time.
That's a very simplified look at the
principles behind WCDMA.
What
if WCDMA isn't covered?
If your phone uses WCDMA and you enter an
area where the networks don't yet support it, the phone are designed to
automatically switch to using GPRS or EDGE, whichever is available. This is
built in to Nokia models - they're called multimode WCDMA/EDGE terminals.
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