Cellular Mobile Generations

7/29/2019 Cellular Mobile Generations

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The first generation cellular moblie communication:(1980 )

Analog communication Shortages: Only lower Frequency available, same Frequency

band Inference, poor Security. Advantages: Convenience for communication


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The second generation cellular mobile communication:(1992)

Digital Communication Advantages: Higher Frequency available, good Security, higher

Capacity, good speech QoS


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Digital traffic channels first-generation systems are almostpurely analog; second-generation systems are digitalEncryption all second generation systems provide encryptionto prevent eavesdropping

Error detection and correction

second-generation digitaltraffic allows for detection and correction, giving clear voicereceptionChannel access second-generation systems allow channels tobe dynamically shared by a number of users


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3G stands for Third Generation and refersto mobile phone technology, specificallythe ability to deliver voice, data andstreaming files, including multimedia

files, for use on a wireless phone.

3G mobile technology is much faster than1G and 2G technology. 1G refers to

analog phone service, and 2G to digitalservice. 3G refers to voice, data andstreaming multimedia, including largepackets of data such as PPT files.


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Voice quality comparable to the public switchedtelephone network144 kbps data rate available to users in high speedmotor vehicles over large area

384 kbps available to pedestrians standing ormoving slowly over small areaSupport (to be phased in) for 2.048 Mbps for officeuse

Symmetrical and asymmetrical data transmissionrates


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Support for both packet switched and circuitswitched data servicesAn adaptive interface to the internet to reflectefficiently the common asymmetry between

inbound and outbound trafficSupport for a wide variety of mobile equipmentFlexibility to allow the introduction of new servicesand technologies


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IMT-2000 is simply a term used by theInternational Telecommunications Union (ITU) torefer to many third generation (3G) wirelesstechnology, that provide higher data speed

between mobile phones and base antennas.

IMT-2000 adopted the alternatives schemes:UMTS ( universal mobile telecommunications system)W-CDMA (IMT-DC)TD-CDMA (IMT-TC)CDMA-2000 (IMT-MC)TDD (IMT-SC)DECT+ (IMT-FT)


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UMTS will offer a wide range of voice, data andmultimedia services. Data rates will reach from 114to 2000 kbps ( or 2 Mbps) depending on weatherthe user is stationary or in motion.

UMTS offers a consistent set of services to mobilecomputer and phone users, no matter where theyare located in the world.


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, an acronym for ,is a channel access method based on using spreadspectrum across multiple time slots. It is shownthat a mixture of TDMA and CDMA provides

better quality of service for multimediacommunication in terms of data throughput andvoice/video quality.


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is a familyof 3G mobile technologystandards, whichuse CDMA channel access, to

send voice, data,and signaling data betweenmobile phones and cell sites.


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( ) (also knownas ( ), or

( )

)is a digital mobile phone technology thatallows improved data transmission ratesas a backward-compatible extensionof GSM. EDGE is considered a pre-3Gradio technology and is partof ITU's 3G definition.
http://en.wikipedia.org/wiki/Mobile_phonehttp://en.wikipedia.org/wiki/Backward-compatiblehttp://en.wikipedia.org/wiki/GSMhttp://en.wikipedia.org/wiki/ITUhttp://en.wikipedia.org/wiki/3Ghttp://en.wikipedia.org/wiki/3Ghttp://en.wikipedia.org/wiki/ITUhttp://en.wikipedia.org/wiki/GSMhttp://en.wikipedia.org/wiki/Backward-compatiblehttp://en.wikipedia.org/wiki/Backward-compatiblehttp://en.wikipedia.org/wiki/Backward-compatiblehttp://en.wikipedia.org/wiki/Mobile_phone


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Soft Handoff Mobile station temporarily connected to more than one

base station simultaneously.

Common Design Issues:-Bandwidth

An important design goal for all 3G system is to limitchannel usage to 5 MHz

Chip rateIt depends on desired data rate, need for error control, and

bandwidth limitations. A chip rate of 3 Mcps or more isreasonable .


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Channel bandwidth : 5 MHz Forward RF channel structure: Direct spread Chip rate: 3.84 Mcps

Frame length: 10 ms Number of slots/frames: 15 Spreading modulation: Complex spreading

circuit

Data Modulation: QPSK (quadratic phase shiftkeying) (forward)BPSK (Binary phase shiftkeying) (reverse)


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Several times higher data speed;Enhanced audio and video streaming;Video-conferencing support;Web and WAP browsing at higher speeds;IPTV (TV through the Internet) support.


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Cellular Mobile Generations

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