> If this term is more than just
> hyperspeak, I'd appreciate any
> information that defines the
> differences between 1, 2 and 2.5G
> devices.
I have found this so far:
1G
First generation wireless: analog cellphones.
2G
Second generation wireless: digital cellphones.
2.5G
Improvement of the speed of data for enhanced e-mail and Internet
access.
3G
Third generation wireless: digital plus high-speed data and global
roaming. Known as IMT-2000 by the ITU and implemented in Europe as UMTS,
cdma2000 in North America and W-CDMA & cdma200 in Japan. The
characteristics of the third-generation handsets will mainly consist of
three points: a very high bit rate, enhanced communications and
multimedia enabled.
4G
fourth generation wireless: mobile devices, which are able to send and
receive data at up to 12 megabits per second, six times faster than 3G
phones. At such speeds, the quality of video will be similar to a
conventional television broadcast.
------
Also, from Techweb, here is a definition of wireless generations
(http://www.techweb.com/encyclopedia/defineterm?term=wireless%20generati
ons)
The first generation (1G) of mobile cellular communications systems were
analog such as AMPS, TACS and NMT. Primarily used for voice, they were
introduced in the late 1970s and early 1980s. Starting in the 1990s,
second generation (2G) systems used digital encoding and include GSM,
TDMA and CDMA. Except for GSM's SMS text message service, 2G systems
have been used mostly for voice. Between now and the third generation
(3G), which is expected in the 2003-2005 timeframe, a variety of 2G+, or
2.5G, techniques are being employed to improve the speed of data for
enhanced e-mail and Internet access. These technologies include packet
enhancements for GSM (GPRS), improved data rates for GSM and TDMA (EDGE)
and improved data rates for CDMA (IS-95B and HDR).
The third generation (3G) is defined by the ITU under the IMT-2000
global framework and is implemented regionally in Europe (UMTS), North
America (cdma2000) and Japan (NTT DoCoMo). 3G is designed for high-speed
multimedia data and voice. Its goals include high-quality audio and
video and advanced global roaming, which means being able to go anywhere
and automatically be handed off to whatever wireless system is available
(inhouse phone system, cellular, satellite, etc.).
Andrea
--
Andrea Hoffmann --- Editor-in-Chief --- MMJ
hoffmann_at_mobilemediajapan.com - http://mobilemediajapan.com
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Received on Mon Mar 12 04:35:59 2001