p001. 4g technology, surya engg cllg

7/29/2019 P001. 4G TECHNOLOGY, Surya Engg Cllg

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SURYA ENGINEERING COLLEGE

Paper Presentation on

4G TECHNOLOGY

SUBMITTED BY

M.THARUN PRASATH,

I Year CSE,

E-mail: [email protected]


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4G TECHNOLOGY

Abstract : The main aim of

our paper is to bring forth

the detail about the low

cost wireless internetaccess for rural area

through the 4G technology

wi-fi (IEEE 802.11n).

Although a large

number of Internet usersnow enjoy high-speed

access, there are still vast

geographic regions wherebroadband services are

either prohibitivelyexpensive or simply

unavailable at any price.Researches and

technology are more

needed for rural areaswhere the development is

lacking.

Hence our paper

analyses the cost and

effectiveness of all possible technologies suchas Cisco Aeronet Bridge

based system, tethered

Aerostat based network,and mesh network to find

the suitable broadband

access technology forrural people in a bearable

cost.

Introduction

The 4G technologies areall about improving theperformance of todaysmobile networks, and alsorevolutionizing the modelto create a truly ultra-

broadband mobileexperience.The international

telecommunicationsregulatory andstandardization bodies areworking for commercialdeployment of 4Gnetworks roughly in the2012-2015 time scale.

Why move towards 4G

Limitation to meetexpectations ofapplications likemultimedia, fullmotion video,wirelessteleconferencingWider Bandwidth

Difficult to moveand interoperate

due to differentstandardshampering globalmobility andservice portability

Primarily Cellular(WAN) withdistinct LANs;need a newintegrated network

Limitations in

applying recentadvances inspectrally moreefficientmodulationschemes

Need all digitalnetwork to fully


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utilize IP andconverged videoand data

What is 4G?

4G is a term used todescribe the next completeevolution in wirelesscommunications. A 4Gsystem will be able toprovide a comprehensiveIP solution where voice,data and streamedmultimedia can be given tousers on an "Anytime,Anywhere" basis, and athigher data rates thanprevious generations.

Objectives of 4G

1) 4G will be a fully IP-based integratedsystem.

2) 4G will be capable ofproviding between 100Mbit/s and 1 Gbit/s

speeds both indoorsand outdoors, withpremium quality andhigh security.

3) 4G will use smartantennas.

4) It will be multipleinputs and multipleoutputs (MIMO)system based

5) Dynamic packetassignment

6) Wideband orthogonalfrequency divisionmultiple access(OFDM)

Key 4G Technologies

Some of the keytechnologies required for4G are described below:

1. OFDM

technology2.

Orthogonal frequencydivision multiplexing(OFDM) is a modulationtechnique that divides thecommunication channelinto a number of equallyspaced frequency bands. Asubcarrier carrying aportion of user informationis transmitted in eachBand. Each subcarrier isindependent of each other.

OFDM transmits datasimultaneously over alarge number of channelsat different frequency,enables to send a largedata. Hence high speedinformation transmissionoccurs.

Fig.1 : OFDM subcarriers

OFDM not only providesclear advantages forphysical layerperformance, but also aframe work for improvinglayer 2 performance by

Useri

Userj

Userk

Userl

User

m

Subcarriers

1 2 3 4 5 N


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proposing an additionaldegree of freedom. UsingOFDM, it is possible toexploit the time domain,the space domain, the

frequency domain, eventhe code domain tooptimize radio channelusage. It ensures veryrobust transmission inmulti-path environmentswith reduced receivercomplexity.

Fig .2: OFDM infrequency domain

As shown in the fig. 2 thesignal is split intoorthogonal subcarriers, oneach of which the signal isnarrowband (a few kHz)and therefore immune tomulti-path effects,providing a guard intervalsis inserted between each

OFDM symbol. OFDMalso provides a frequencydiversity gain, improvingthe physical layer performance. It is alsocompatible with otherenhancement technologies,

such as smart antennas andMIMO.

It can also be employed asa multi access technology

(OFDMA). In this case,each OFDM symbol cantransmit informationto/from several users usinga different set of flexibilityfor resource allocation(increasing the capacity)but also enables cross-layer optimization of radiolink usage.

OFDMA has beingmodulation technique forWLAN, digital audiobroad cost systems, digitalvideo broad cost systemsand a candidate for futuremobile systems.

3. MIMO system

4.

The multiple inputmultiple output (MIMO)technology was decided toadd to IEEE802.11nstandards. MIMO is afamily of technologies formulti antenna wirelesstransmission and receptionthat increases theachievable data throughputwithin the same occupiedbandwidth, increasesquality of communication,and allowing dramaticallyincreased spectralefficiency, while offeringsustainable benefits tosystem performance, italso increases thechallenges in design and


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system evaluation andvalidation.

Multiple antennas at boththe base station and

terminal can significantlyincreases data rates withsufficient multipath. Ituses signals multiplexingbetween multipletransmitting antennas(space multiplex) and timeor frequency.

MIMO is well suited forOFDM, as it is possible

to process independenttime symbols as soon asthe OFDM waveform iscorrectly designed for thechannel. This process ofOFDM greatly simplifiesthe process. The signaltransmitted by m antennasis received by n antennas.Processing of receivedsignals may deliver severalperformanceimprovements: range,quality of received signalsand spectrum efficiency

Fig. 3: MIMO strategy

3. Smart antenna

Smart antennas are basestation antennas that use

digital signal processing tocancel interference. Itprovides sustainableinterference suppressionfor enhanced performance.

Fig. 4: smart antenna

Fig.5 smart antenna in

side & top view

A smart antenna combinesmultiple antenna elementswith a signal-processingcapability to optimize itsradiation and/or receptionpattern automatically in

response to the signalenvironment .it amplifiesthe frequency to user whowants to communicate andit can be adopted toOFDM and SDR


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Fig.6 radiation pattern of

smart antenna

5. Software Defined

Radio

6.

SDR technology isenabling frequencies andcommunication methodsand to be changed flexibleby means of software. Itresponses to internetprotocol version 6 (IPV6).SDR benefits from todayshigh processing to developmulti-band, multi-standardbase stations andterminals.

Although in future theterminals will adapt the airinterface to the availableradio access technology, atpresent this is done by theinfrastructure. Severalinfrastructure gains areexpected from SDR.

For example to increasethe network capacity at aspecific time (eg. Duringsports event), an operatorwill reconfigure itsnetwork adding severalmodes at a giventransceiver station (BTS).SDR makes thisreconfiguration easy.

In the context of 4Gsystems, SDR will becomean enabler for the

aggregation of multi-standard Pico/micro cells.For the manufacture, thiscan be a powerful aid toproviding multi-standard,multi-band equipment withreduced developmenteffort and costs throughsimultaneous multi-channel processing.

Interlayer optimization

The most obviousinteraction is the onebetween MIMO and theMAC layer. Other interactions have beenidentified in fig.7

Emerging 4G

technologies

1. wi-fi( IEEE.802.11n)


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2. wi-max (IEEE802.16e)

3. 3GGP LTE4. UMB

Low cost wireless

Internet access through

wi-fi for rural area

The condition of the

Rural Area

Researches andTechnologies are moreneeded wheredevelopment is lacking,that is, in the developing

regions of the world.however technologymeant for developedtelecom economics areoften too cost, or otherwise unsuitable foruse in rural regions of thethird world. Thus, despitethe enormous benefitsenjoyed through thecellular revolution by

people in metropolitanareas of developingcountries like India,penetration of thetechnology in rural areas ispoor or non-existent.

Why the Penetration ofTechnology is less in

Rural Area?

The reasons for this are thelow population density inrural (in comparison withcities) and the low payingcapacity of users there.The cost of technology isimportant factor in

deciding its applicabilityfor rural use.

Issues with current

approach

1. Tower cost is veryhigh

2. The cost of directional antennasis very high. But to

some extentdirectional antennasis unavoidable.

3. Alignment of villages based clientdirectional antennais an expensiveproposition.

corDECT(IIT-madras,

TeNeT Group)

corDECT is a wirelesslocal loop standarddeveloped in India by IITMadras and MidasCommunications atChennai, under leadershipof Prof Ashok

Wired10/100

Mbps

Wi -fi802.11b

Hot spot TataSatyam

Reliance

Dial Up

(56.6 Kbps

DSL

Wireless

Line of sight

Cable

modemCorDECT

LANLAN ISMISMAccess

technologies

Access

technologies

Fiber in

The loop

Cell phones

802.11d,e

Based (Wi -max

802.11b

Based


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Jhunjhunwala, based onthe DECT digital cordlessphone standard.

The technology is a Fixed

Wireless Option, whichhas extremely low capitalcosts and is ideal for smallstart ups to scale, as wellas for sparse rural areas. Itis very suitable for ICT4Dprojects and India has onesuch organization, n-Logue Communicationsthat has aptly done this.

The full form of DECT is

Digital EnhancedCordlessTelecommunications,which is useful indesigning small capacityWLL (wireless in localloop) systems. Thesesystems are operative onlyon LOS Conditions andare very much affected byweather conditions.Systemis designed for rural and

sub urban areas wheresubscriber density ismedium or low.

"corDECT" systemprovides simultaneousvoice and Internetaccess.The new generationcorDECT technology iscalled BroadbandcorDECT which supports

& provides broadbandInternet access overwireless local loop.

It is low cost technologydesigned for ruralaccesses. However thebandwidth achievable withcorDECT are much

lower .BB corDECT is anew version from TeNeTGroup. It is commerciallydeployed in few thousandvillages and it has also

been deployed in Egypt,some African countries

Wi-Max (IEEE 802.16d/e) does the same and itpromises broadbandspeeds but at much higherprice points.

Fig. 9: corDECT system

Cisco Aeronet BridgeBased SystemThe Cisco aironet wireless

bridge enables high speed(11 mbps), long-rangeoutdoor lines up to 25

miles (40.2 km).


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Channel 1

Channel 2

Channel 3

3- sector antenna, each $300

Cisco wirelessbridge 1

Cisco

brid

Cisco wi relessbridges

Pole $100Antenna $300

Fig.10:connectivity using

Cisco

wireless Bridge

Installation amount in

US$

Base stationclient side

Tethered Aerostat

approach

An aerostat is a lighterthan air object that canstay stationary in the air.The main envelope isfilled with helium. Itserves as a tower to hold

omni directional antennaat the base station. Itconsists of antenna, router,and power over Ethernetcables. Its height is about50 to 100 m.

Fig . 11: An aerostat

Cost of aerostat

assembling

Aerostat US$

EnvelopeTetherWinchFirst time to fill helium

80080

120200

Total 1200.00

Running cost: refilling theaerostat once a month -US$ 40.00

Cost of aerostat basedassembly

Base stationclient side

Prices of PC, Printer,power supply etc notincluded.

Advantages of Aerostat

assembly

Aerostat 1200

Wi-Fi 300

Omniantenna

400

Total 1900

Pole 100

Ciscobridge

2000

1-D

antenna

300

Total $2400


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1. low cost2. easy to deploy3. portable4. Useful for hilly

terrain and rapid

deployment.

Disadvantages

1. periodic refillingfor helium

2. transportation ofhelium

3. may require moremaintenance

Wi-Fi using mesh

network

Access

po int

TX /RX

f iber

V i l l a g e n o d e

A d H o p A r c h i t e c t u r e

Fig . 12 Mesh network

India has 600million

Rural population

India has total of 6,00,000villages in India and itspopulation per village isapproximately 500 to1000. The average villagearea is 6 sq.km and theaverage distance betweeneach village is 2 to 2.5 km

Connect each village to

the Internet

Mesh network coversapproximately 600 sq.kms.Hence 120 villages will beconnected by each accesspoint (AP) of meshnetwork. Some of villagenodes (STA) gropedtogether forms Ad hocnetwork (multi hoparchicture).

Multi-Hop networking

In mesh network the multihop peer-to-peer paths areformed replacing thesingle hop (from and to theAP) paths. In addition thedirect communicationbetween nodes (withoutany participation of theAP) becomes possible.Fig.13:Ad hoc

architecture (without

AP)

The benefits of theadaptation of the peer-to-peer paradigm within aWLAN a include mainlyreduced energyconsumption and thepossibility for multiplesimultaneoustransmissions over theshared medium, which areexpectations to lead toincrease bandwidth.

Villagenode


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The AP is the onlynode capable of providingbackbone connectivity.Each Hop isapproximately 2 to 2.5 km

and the maximum Hop tofiber drop is 6.

Fig.14: Mesh network

Cost of Mesh Network in

US $

Steps to set up mesh AP

1. mind set2. hardware3. software4. first node5. Wiana registration6. access controls7. more nodes8. deployment of

nodes9. testing mesh

connectivity10. feed back and

routing11. contributing to

locustworld

DGP project

It was initiated at the IITKanpur (IITK), utterPradesh, to explore the

technical feasibility ofestablishing long-distance802.11 links. Fig 1 showsDGP network as it hasevolved over time we havea central location calledthe landline node whichhas wires internetconnectivity.

In the DGP test bed, this isthe IITK location. Wehave many long-distance(up to several tens of kms)802.11 links formed usinghigh gain directionalantennas. Long-distancelinks connect varioussurrounding villages to theland line through a multi-hop mesh network. theDGP network primarily

been used as a testbed foraiding various protocolstudies , although we dohave developed peopleusing communicationservices at many

locations.

Ashwini project

It is a network deploymenteffort by the byrrajufoundation, to providebroadband access and

Equipment Cost10-15 m mast 100

Access point 100

Omni directional antenna 75

Total $ 275

STA STA STA STA

MPR

MAP

MP

MAP

MAP

MP


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services to a collectionof villages in thewest

Godavari district of

Andhra Pradesh, India.This is a service centricdeployment and currentlya variety ofInteractive video-basedapplications such asdistance-education, tele-medicine etc are being run

on the network. Fig 3shows the currently activelinks in the ashwininetwork. Here thebhimavaram location is the

landline node. It is worthnoting that a future 17nodes will be included inthe network in the nearfuture.

Advantages of 4G

As the networks movefrom generation togeneration, more and moreservices are provided.Here is few of them,

1. seamless mobility2. efficient support of

various services atanytime anywherebasis

3. maintaining Qos ascompared withwire-line network

4. higher bit ratesfrom 10 mbps to100 mbps

5. economicdeployment of systems

Conclusion

Wireless communicationis an unending, undyingfield which will prosperas long as the humanrace exist. To make Indiaa leader in wirelesstechnology, the awarenessand adaptation of thetechnologies forth comingnew generation are neededand there is a need forconducting mission

DGP project test bed


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oriented research for 4Gtechnology to give it to thepeople with low cost.

References

1. Ashok Jhunghunwala,next generationwireless TeTeKGroup, IIT madras.

2. Dr.BhasakaranRaman andKameswariChebroduExperiences inusing wi-fi for rural internet inIndia IndianInstitute of Technology,Kanpur

3. Stephen McLaughlin,Broadbandcommunications

college of Engineering andelectronics,University of Edinburgh.

4. IEEE network magazine

5. www.google.com

p001. 4g technology, surya engg cllg

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