..is the transfer of information over a distance , without the use of electrical conductors/wires.

Mobile radio telephone systems preceded modern cellular mobile telephony technology. These systems are sometimes retroactively referred to as pre cellular (or sometimes Zero

Generation) systems.

First Mobile Radio Telephone-1924

Used analog radio signal.Introduced in 1980’sUses FDMA

The various standards--

As Its Analog So It Was Highly Susceptible

To Noise

Traffic Was Not Encrypted So Anyone Could

Eavesdrop By Tuning To The Correct

Frequency

2G WirelessThe technology of most current

DIGITAL mobile phones-TDMA + CDMA

Features includes:- Phone calls- Voice mail- Receive simple TEXT messages

Speed: 10kbits/secTime to download a 3min MP3 song: 31-41 min

Different variants of

2G

GSM(TDMA)

IS-95CDMA one

PDC(TDMA)

iDEN (TDMA)

IS-136D-AMPS

The Best Technology now widely available

Features includes:- camera phones- high speed packet data- GPRS- Send/receive large email messages- Web browsing- Navigation/maps- New updates

Speed: 64-144kb/secTime to download a 3min MP3 song: 6-9min

Features include:

I-MODE DATA SERVICE.

CAMERA PHONES.

HIGH SPEED CIRCUIT SWITCHED

GPRS

EDGE

2G networks were built mainly for voice data and slow transmission. Due to rapid changes in user expectation, they do not meet today's wireless needs.Cellular mobile telecommunications networks are being upgraded to use 3G technologies from 1999 to 2010. Japan

was the first country to introduce 3G nationally, and in Japan

the transition to 3G was largely completed in 2006. Korea

then adopted 3G Networks soon after and the transition was

made as early as 2004.

Combines a mobile phone, laptop PC and TV

Features includes:- Phone calls/fax- Global roaming- Send/receive large email messages- High-speed Web- Navigation/maps- Videoconferencing- TV streaming- Electronic agenda meeting reminder.

Speed: 144kb/sec-2mb/secTime to download a 3min MP3 song: 11sec-1.5min

UMTS- This Is Main 3G Technology That Uses WCDMA..

WCDMA (WIDEBAND CODE DIVISION MULTIPLE ACCESS)

-WCDMA is the higher speed transmission protocol in the UMTS system-Radio channels are 5MHz wide.-Supports two basic modes of duplex: frequency division and time division(15 slots/radio frame). -Multiuser detection can be used to increase capacity and coverage-operators like VODAFONE, SINGTEL, AT&T, TIM.

Data Communications And Networking- B. A. Forouzanwww.Wikipedia.comwww.nmscommunications.comwww.mobilealliance.comEncarta Encyclopedia