2G Wireless Telephone Technology

8/9/2019 2G Wireless Telephone Technology

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BY:ADITYA SHARMA


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2G wirelesstelephonetechnology

INTR

ODOCTION

TYPES

2G TECHNOLOGY

ADVANTAGES

DISADVANTAGES
http://en.wikipedia.org/wiki/Wirelesshttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Technologyhttp://en.wikipedia.org/wiki/Technologyhttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Wireless


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INTRODOCTION 2G is short for second-generation wireless

telephone technology. Second generation 2G

cellular telecom networks werecommercially launched on the GSM standardin Finland by Radiolinja (now part of ElisaOyj) in 1991. Three primary benefits of 2Gnetworks over their predecessors were thatphone conversations were digitallyencrypted, 2G systems were significantlymore efficient on the spectrum allowing forfar greater mobile phone penetration levels;and 2G introduced data services for mobile,starting with SMS text messages.


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INTRODOCTIONAfter 2G was launched, the previous mobile

telephone systems were retrospectivelydubbed 1G. While radio signals on 1G

networks are analog, and on 2G networksare digital, both systems use digitalsignaling to connect the radio towers(which listen to the handsets) to the rest

of the telephone system. 2G uses digital radio signals


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TYPES2.5G also called (GPRS)

2.75G also called (EDGE)


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2.5 G (GPRS)

2.5G is a stepping stone between 2G and 3G

cellular wireless technologies. The term"second and a half generation" is used todescribe 2G-systems that have implementeda packet switched domain in addition to the

circuit switched domain.The first major step in the evolution of GSM

networks to 3G occurred with theintroduction of General Packet Radio Service

(GPRS). So the cellular services combinedwith enhanced data transmission capabilitiesbecame known as '2.5G.'


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2.5 G (GPRS)GPRS could provide data rates from 56 kbit/s

up to 114 kbit/s. It can be used for servicessuch as Wireless Application Protocol (WAP)access, Multimedia Messaging Service (MMS),and for Internet communication services suchas email and World Wide Web access. GPRSdata transfer is typically charged permegabyte of traffic transferred, while data

communication via traditional circuitswitching is billed per minute of connectiontime.


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2.75G (EDGE)GPRS networks evolved to EDGE networks with

the introduction of 8PSK encoding. EnhancedData rates for GSM Evolution (EDGE),Enhanced GPRS (EGPRS), backward-

compatible digital mobile phone technologythat allows improved data transmissionrates, as an extension on top of standardGSM. EDGE was deployed on GSM networks

beginning in 2003initially by Cingular (nowAT&T) in the United States.


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2.75G (EDGE)EDGE is standardized by 3GPP as part of the

GSM family, and it is an upgrade thatprovides a potential three-fold increase incapacity of GSM/GPRS networks. The

specification achieves higher data-rates (upto 236.8 kbit/s) by switching to moresophisticated methods of coding (8PSK),within existing GSM timeslots


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2G technologies2G technologies can be divided into TDMA-

based and CDMA-based standards dependingon the type of multiplexing used. The main2G standards are


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2G technologies GSM (TDMA-based), originally from Europe but

used in almost all countries on all six inhabitedcontinents (Time Division Multiple Access).Today accounts for over 80% of all subscribers

around the world. Over 60 GSM operators arealso using CDMA2000 in the 450 MHz frequencyband (CDMA450).

IS-95 aka cdmaOne (CDMA-based, commonlyreferred as simply CDMA in the US), used in the

Americas and parts of Asia. Today accounts forabout 17% of all subscribers globally. Over adozen CDMA operators have migrated to GSMincluding operators in Mexico, India, Australiaand South Korea.


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2G technologiesPDC (TDMA-based), used exclusively in Japan

iDEN (TDMA-based), proprietary network usedby Nextel in the United States andTeluSMobility in Canada

IS-136 aka D-AMPS (TDMA-based, commonlyreferred as simply TDMA in the US), wasonce prevalent in the Americas but mosthave migrated to GSM.


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advantageGreatly reduced fraud. With analog systems it

was possible to have two or more"cloned"handsets that had the same phonenumber.

Enhanced privacy. A key digital advantage that2G phones are immensely more private than1G phones, which have no protection againsteavesdropping.


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disadvantage In less populous areas, the weaker digital signal

may not be sufficient to reach a cell tower. Thistends to be a particular problem on 2G systemsdeployed on higher frequencies, but is mostlynot a problem on 2G systems deployed on lowerfrequencies. National regulations differ greatlyamong countries which dictate where 2G can bedeployed.

While digital calls tend to be free of static and

background noise,the range of sound that theyconvey is reduced. You'll hear less of thetonality of someone's voice talking on a digitalcellphone, but you will hear it more clearly.


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disadvantageAnalog has a smooth decay curve, digital a

jagged steppy one. This can be both anadvantage and a disadvantage. Under goodconditions, digital will sound better. Under

slightly worse conditions, analog willexperience static, while digital hasoccasional dropouts. As conditions worsen,though, digital will start to completely fail,

by dropping calls or being unintelligible,while analog slowly gets worse, generallyholding a call longer and allowing at least afew words to get through.


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GSM FAMILY technology


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THANK YOU

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2G Wireless Telephone Technology