What is 1g 2g 2.5g 3g 3.5g 3.75g 3.9g 4g Check the difference explained

GSM means Global
System for Mobile
Communications

In 1982
1G
First Generation
was introduced where
network signals were
analogue and used
Frequency Division Multiple Access (FDMA)

2G
Second Generation waslaunched in 1992 in which
signals and speech
channels were digitally
encrypted. 2G used Time
Division Multiple Access (TDMA)

2.5G
Deployed in 2003
which implemented High
Speed Circuit Switched Domain(HSCSD) Data rate
236.8kbps to 384kbps by using Enhanced Data Rate
for GSM Evolution (EDGE)

3G
has very different
functions like it allows
simultaneous use of speech
and data services at higher
rates and better spectral
efficiency.

3G Standard International Mobile
Telecommunications
IMT-2000 which is
popularly known as 3G
or 3rd Generation standard for mobile phones and telecommunications services to make 3G globally applicable.

3G UMTS Universal Mobile
Telecommunications
System uses W-CDMA
WideBand-Code Division
Multiple Access as main
interface. Also known with other names. In
Japan called FOMA
Freedom Of Mobile
Multimedia Access. In
China known as TD-
SCDMA Time Division- Synchronous Code
Division Multiple Access.
Basically all these are
variants which uses
different radio
interface. W-CDMA networks can
give speed upto
384kbps maximum.

3.5G
HSUPA upgrades the uplink for higher
data transfer speed and
capacity of 1.4 ,1.9 ,5.8
Mbps.

HSUPA name is given by Nokia and used in its phones only
but 3GPP does not
support this name.
HSDPA High-Speed
Downlink Packet Access
having faster speed from 1.8 ,3.6 ,7.2 to 14
Mbps.

3.75G
HSPA High Speed Packet Access is a
combination of HSUPA
and HSDPA that
improves the
performance of W-
CDMA and can attain speed 21Mbps to
28Mbps. HSDPA High-Speed Downlink Packet Access
having faster speed
from 1.8 ,3.6 ,7.2 to 14
Mbps.

3.9G HSOPA Some networks dubbed it as
4G. This project is
known as Long Term
Evolution and uses OF-
DMA Orthogonal
Frequency-Division Multiplexing which will
offer data rate at
170Mbps for up-link
and 320Mbps for down-
link.

4G Constitute of 4G has not been standardized
yet.It is non-backward
compatible with new
higher frequencies
bands. It is defined to
be comprehensive and secure for the users. 4G
will only be packet-
based (all-IP) switched
network. Facilities like
IP-telephony (IP-based
voice data), Ultra- broadband internet Access 1GBps (Gigabit
speed) Support for IPV6
protocol, Gaming
Services, High Definition
HDTV, Streamed
Multimedia and many more new services are
added!!! UMTS operates on
frequencies of
850/900/1700/1900/2100
MHz. Most 3G phones
support at least 2
frequencies. No 3G phone available which supports all 3G
frequencies.
It depends on service
provider what speed
and frequency it adopts
for its 3G network and what type of 3G
compatible phone you
have to fully
exploit ,utilize and
enjoy the services.