Confused by all the technical jargon and
acronyms surrounding 3G? We can't blame you. Here's a quick
guide to the terms you'll need to know.
1xEV-DO: Also known as Evolution, Data-Only,
this subset of CDMA2000 runs on CDMA networks and reaches peak
speeds of 2.4Mbps and averages 300Kbps to 600Kbps. As its name
implies, EV-DO networks handle only high-speed data; handsets
supporting EV-DO would use the underlying CDMA network for voice
calls. Both Verizon and Sprint are launching 1xEV-DO service.
1xEV-DV: Also known as Evolution,
Data-Voice, 1xEV-DV is the next step in CDMA2000 technology
after 1xEV-DO, handling both data and voice calls at speeds up
1xRTT: A subset of CDMA2000 that runs on
CDMA networks, 1xRTT (or Radio Transmission Technology) offers
speeds of up to 144Kbps, although users will typically get
speeds between 60Kbps and 80Kbps. While 1XRTT is sometimes
referred to as 3G technology, it falls a bit short in terms of
speed and actually is 2.5G. Both Sprint and Verizon support
AMPS: Advanced Mobile Phone Service, the
first-generation, analog cellular network that arrived in the
United States in the 1980s. While digital networks have taken
over most populated areas in the United States, AMPS still
covers rural areas that CDMA and GSM can't reach.
CDMA: Code-Division Multiple Access, a 2G
digital cellular network first launched in 1995 and--until a
recent surge by 2G competitor GSM--the unchallenged leader in
stateside cell service. Wireless carriers Verizon and Sprint
both use CDMA.
CDMA2000: The next step in CDMA technology,
CDMA2000 comprises 1xRTT (2.5G), 1xEV-DO, and 1xEV-DV (both 3G).
EDGE: Enhanced Data rates for GSM Evolution
(or Enhanced Data GSM Environment), a 2.5G enhancement for GSM
with a theoretical top speed of 384Kbps, although real-world
speeds will be closer to 90Kbps.
GPRS: An upgrade for GSM networks, General
Packet Radio Service is a 2.5G technology that bumps data speeds
up to 50Kbps, although real-world speeds are closer to 30Kbps
GSM: Global System for Mobile
Communications. This 2G (about 9.6Kbps) digital network is most
pervasive in international markets, although it's made
significant headway in the United States.
HSDPA: An enhancement for 3G UMTS networks,
High Speed Downlink Packet Access promises bone-rattling speeds
of up to 14.4Mbps, compared to a "mere" top speed of 2Mbps for
iDEN: A 2G network primarily used for
business. Nextel was the first cellular network with PTT
functionality but it now is offered by others.
PTT: Push to talk, a two-way mobile
technology that works like a walkie-talkie and is not the same
as placing a normal voice call.
TDMA: Time Division Multiple Access, the
original digital technology on which GSM is based.
UMTS: Universal Mobile Telephone Service,
the 3G service that GSM carriers Cingular and T-Mobile plan to
roll out for its subscribers. UMTS boasts speeds of up to 2Mbps,
although users will typically see speeds in the
WiMax: A high-performance version of Wi-Fi,
WiMax (or 802.16) networks would offer the bandwidth of Wi-Fi at
ranges measured in miles rather than feet. Many industry
observers feel that WiMax could be the cornerstone of 4G
wireless networks, boasting speeds rivaling those of wired
gigabit Ethernet networks.