4G mobile communications

(The future technology of mobiles)

ABSTRACT
4G is a short for fourth generation cellular communication systems. It is a network that operates on Internet technology, combines it with other applications and technologies such as Wi-Fi and WiMAX, and runs at speeds ranging from 100 Mbps in cell-phone

networks! to 1 Gbps in local Wi-Fi networks!. "he key concept is integrating the #$ capabilities with all of the e%isting mobile technologies through ad&anced technologies. "he key technologies like OFDM, Multiantenna systems, SDR are useful in making #$ a reality. "he transmission of multimedia applications at faster rates is

achie&ed speed

by data

Cache

and

Pico-cell increased

methods. "he factors like low cost, high transfer' microprocessor performance has mo&ed the #$ forward. "he #$ is successfully implemented in (apan and soon )outh *orea will follow it. "he killer application of #$ is not clear, though the impro&ed bandwidths and data throughput offered by #$ networks should provide opportunities for and pre&iously impossible products

IND !
1. Introduction 2. Evolution 3. Objectives 4. Key 4G technologies
4.1 OFDM 4.2 Multi ntenn! syste"s 4.3 #o$t%!re de$ined r!dio 4.4 &!ching !nd 'ico cells

(. ccess sche"es ). &over!ge *. Drivers +.Fe!tures ,. --lic!tions 1.. &onclusion 11. /e$erences

ser&ices to be released. +ne of the terms used to describe #$ is M G!C Mobile multimedia, Anytime anywhere, $lobal mobility support, Integrated wireless solution, ser&ice.! and ,ustomi-ed personal

"# INTR$D%CTI$N
The 4G will be a fully IP-based integrated system o" systems and net#o$% o" net#o$%s achieved after the convergence of wired and wireless networks as well as computer, consumer electronics, communication technology, and several other convergences that will

be capable of providing 100 Mbps and 1Gbps, respectively, in outdoor and indoor environments with end-to-end QoS and high security, offering any kind of services anytime, anywhere, at affordable cost and one billing. The ireless # operates on orld !esearch "orum !"$ defines 4G as a network that %nternet technology,

combines it with other applications and technologies such as i&"i and iM'(, and runs at speeds ranging from 100 Mbps #in cell&phone networks$ to 1 Gbps #in local i&"i networks$. 4G is not )ust one defined technology or standard, but rather a collection of technologies and protocols to enable the highest throughput, lowest cost wireless network possible. The official designation from the %*** for 4G is beyond +G #,+G$. This new generation of wireless is intended to complement and replace the +G systems, perhaps in to 10 years. to 'ccessing&information anywhere, anytime, with a seamless connection a wide range of information and services, and receiving a large volume of information, data, pictures, video, and so on, are the keys of the 4G infrastructures. The future 4G infrastructures will consist of a set of 3econd generation #2&( mobile systems were also primarily designed to offer speech with a limited capability to offer data at low rates in 11405s but based on digital technology including digital signal processing techni/ues. These 6G systems provided circuit&switched data communication services at a 'ower s)eed. the competitive rush to design

various networks using %. #%nternet protocol$ as a common protocol so that users are in control because they will be able to choose every application and environment. ,ased on the developing trends of mobile communication, 4G will have broader bandwidth, higher data rate, and smoother and /uicker handoff and will focus on ensuring seamless service across a multitude of wireless systems and networks. The key concept is integrating the 4G capabilities with all of the e0isting mobile technologies through advanced technologies.

2.EV !"#I $
The first generation #%&$ mobile systems were designed in 1120 to offer a single service i.e. speech. These are implemented on ana'og techno'ogy and basic cellular technology of mobile communications. and implement digital systems led again to a variety of different and incompatible standards such as &S*#Global 3ystem Mobile$,+,*-#7ode 8ivision Multiple 'ccess$.these systems operate nationwide or internationally and are today5s mainstream systems although the data rates in these systems are limited.

.& mobile systems are e0pected to offer high&/uality multimedia services and operate in different environments. %t was designed in 11105s for higher /uality voice channels and broadband data capabilities upto 6Mbps. !imitations of .&9 8ifficulty of 78M' to provide higher data rates "or high speed data rates and band width to meet multimedia re/uirements. :imitation of spectrum and its allocation. %nability to roam between

-'' the above limitations and demand for higher access speed multimedia communication in today5s society which greatly depends upon computer communication in digital format seems unlimited. This led to the research and evolution of fourth generation #4G$. The fourth generation will encompass all systems from various networks, public to private; operator&driven broadband networks to personal areas; and ad hoc networks. The 4G systems will interoperate with 6G and +G systems, as well as with digital #broadband$ broadcasting systems. %n addition, 4G systems will be fully %.&based wireless %nternet. This all&encompassing integrated perspective shows the broad range of systems that the fourth generation intends to integrate, from satellite broadband to high altitude platform to cellular +G and +G systems to :: #wireless local loop$ and " '

different services. To provide a seamless transport end&to&end mechanism. To introduce a better system with reduced cost. :'< #wireless local area network$ and .'< #personal area network$, all with %. as the integrating mechanism. . ith 4G,

#fi0ed wireless access$ to a range of new services and models will be available

To cater the /uality of service and rate re/uirements set by the forthcoming

..

/0E+#IVES

applications like wireless broadband access, Multimedia Messaging 3ervice, video chat, mobile T=,

>igh definition T= content, 8=, and minimal service like voice and data at anytime and anywhere, the 4G working groups have defined the following as the ob)ectives of the 4G wireless communication standard

3pectrally efficient system #in bits?s?>@ and bit?s?>@?site$ABC >igh network capacityA2C <ominal data rate of 100 Mbps at high speeds and 1 Gbps at

stationary conditions as defined by the %TD&!A1C

%nteroperable with the e0isting wireless standardsA10C 'll %. system, packet switched networkA1C

8ata rate of at least 100 Mbps between any two points in the worldA1C

3mooth

handoff

across

heterogeneous networkA4C

1. 2E3 1& #E+4$ ! &IES

3eamless connectivity and global roaming networksA1C across

>igh /uality of service for ne0t generation multimedia support #real time audio, high speed data, >8T= video content, mobile T=, etc$A1C

Multiple0ing#E"8M$ not only provides clear advantages for physical layer performance, but also a frame work for improving layer 6 performance by proposing freedom 5,* an additional degree of

Dsing E8"M, it is possible to e0ploit the time domain, the space domain, the fre/uency 8omain and even the code domain to optimi@e radio channel usage. %t ensures very robust transmission in multi&path environments with reduced receiver comple0ity. 's shown in Figure ., the signal is split into orthogonal sub carriers, on each of which the signal is FnarrowbandG #a few k>@$ and therefore immune to multi&path effects, provided a guard interval is inserted between each E"8M symbol. E"8M also provides a fre/uency diversity gain, improving the physical layer performance. %t is also compatible with other enhancement technologies, such as smart antennas and M%ME.E"8M modulation can also be employed technology as a multiple access #Erthogonal "re/uency

Summary of advantages

7an easily adapt to severe channel conditions without comple0 e/uali@ation !obust against narrow&band co& channel interference !obust against %ntersymbol interference #%3%$ and fading caused by multipath propagation >igh spectral efficiency *fficient implementation using ""T :ow sensitivity to time synchroni@ation errors Tuned sub&channel receiver filters are not re/uired #unlike conventional "8M$

1.2. *u'ti-antenna Systems

gained importance for its bandwidth conservation and power efficiency. 3patial multiple0ing involves deploying multiple antennas at the transmitter and at the receiver. %ndependent streams can be transmitted simultaneously from all the antennas. This increases the data rate into multiple folds with the number e/ual to minimum of the

8ivision Multiple 'ccess; E"8M'$. %n this case, each E"8M symbol can transmit information to?from several users using a different set of sub carriers #sub channels$. This not only provides additional fle0ibility for resource allocation #increasing the capacity$, but also enables cross&layer optimi@ation of radio link usage.

number of transmit and receive antennas.

This is called as Multiple&input multiple& output communications #M%ME$. 'part from this, the reliability in transmitting high speed data in the fading channel can be improved by using more antennas at the transmitter or at the receiver. This is called transmit or recei&e di&ersity.

7ombats fading H%ncreases capacity H7ost is scalable with performance 1... Software ,efined 6adio 8S,6( 3oftware 8efined !adio #38!$ benefits from today5s high processing power to develop multi&band, multi&standard base stations and terminals. 'lthough in future the terminals will adapt the air interface to the available radio access technology, at present this is done by the infrastructure. 3everal infrastructure gains are e0pected from 38!. "or e0ample, to increase network capacity at a specific time #e.g. during sports event$, an operator will reconfigure its network base station&to&user

5I&"6E7SP-+E #I*E + ,I$& 5 6 *I* S3S#E*S

adding several modems at a given ,ase Transceiver 3tation #,T3$. 38! makes this reconfiguration easy. %n the conte0t of 4G systems, 38! will become an enabler for the aggregation of multi& standard pico?micro cells. "or a

'8='<T'G*39 %ncreases antennas data rates due to

multiple transmit and receive

manufacturer, this can be a powerful aid to providing multi&standard,multi&band .

e/uipment with reduced simultaneous multi&channel processing

1.1. +aching and Pico +e''s Memory in the network and terminals facilitates service delivery. %n cellular systems, This e0tends the capabilities of the M'7 scheduler, as it facilitates the delivery of real&time services. !esources can be assigned to data only when the radio conditions are favorable. These methods can double the capacity of a classical cellular system. %n pico cellular coverage, high data rate #non&real&time$ services can be delivered even when reception?transmission is interrupted for a few seconds. 7onse/uently, the coverage @one within which data can be received?transmitted can be designed with no constraints other than limiting interference. 8ata delivery is preferred in places where the bit rate is a ma0imum. ,etween these areas, the coverage is not used most of the time,

creating an apparent discontinuity. %n these areas, content is sent to the terminal cache at the high data rate and read at the service rate. 7overages are FdiscontinuousG.The advantage of coverage, especially when designed with caching technology, is high spectrum efficiency, high scalability #from -0 to-00 bit?s?>@$, high capacity and lower cost. ' specific architecture is needed to introduce cache memory in the network. 'n e0ample is shown. 't the entrance of the access network, lines of cache at the destination of a terminal are built and stored. hen a terminal enters an area in which a transfer is possible, it simply asks for the line of cache following the last received. ,etween the terminal and the cache. ' simple, robust and reliable protocol is used between the terminal and the cache for every service delivered in this type of coverage.

PI+

+E!! $E#9 62 ,ESI&$

*u'timedia service de'ivery, service ada)tation and robust transmission

'udio and video coding is scalable. "or instance, a video flow can be split into three "lows which can be transported independently9 one base layer #+0 kbit?s$, which is a robust flow but of limited /uality #e.g.- images?s$, and two enhancement flows #-0 kbit?s and 600 kbit?s$. The first flow provides availability, the other two /uality and =ideo #and audio$ transmissions are currently transmitted without error and without packet loss. >owever, it is possible to allow error rates of about 10& - ?10&B and a packet loss around 10& 6?10&+. 7oded images still contain enough redundancy for error correction. %t is possible to gain about 10 d, in transmission with a reasonable increase in comple0ity. Dsing the described technologies, multimedia transmission can provide a good /uality.

definition. %n a streaming situation, the terminal will have three caches. %n pico cellular coverage, the parent coverage establishes the service dialog and service start&up#with the base layer$. 's soon as the terminal enters .ico cell coverage, the terminal caches are filled, starting with the base cache.

these technologies are limited; T8M' suffers from inherent inefficiencies due to the need for guard periods between frames, and 78M' from poor spectrum fle0ibility and scalability. !ecently, new access schemes like E"8M', 3ingle 7arrier "8M', and M7&78M' have been proposed as part of the upcoming ne0t generation DMT3, 406.1Be and 406.60 standards. These offer the same efficiencies as older technologies like 78M', but offer advantages in scalability. %n addition to improvements in these multiple0ing systems, improved modulation techni/ues are being used. hereas earlier used to mitigate the dwindling number of %.v4 addresses. %n the conte0t of 4G, %.vB also enables a number of applications with better multi&

:. -++ESS S+4E*ES
The e0isting wireless standards use T8M', "8M', 78M' and combinations of these to multiple0 multiple mobile stations #handsets, etc$ use of spectrum, with 78M' #%3&6000, &78M', T8&78M', T8&378M'$ dominating the +G space. >owever, all

cast, security and route optimi@ation capabilities. ith the available address space and number of addressing bits in %.vB, many innovative coding schemes can be developed for 4G devices and applications that could aid deployment of 4G networks and services. mode$

7overage is achieved by adding new technologies #possibly in overlay and progressively enhancing density. Take a iM'( deployment, for

e0ample9 first the parent coverage is deployed; it is then made denser by adding discontinuous pico cells, after which the pico cell is made denser but still discontinuously. "inally the pico cell coverage is made continuous

;. + VE6-&E

either by using M%ME or by deploying another pico cell coverage in a different fre/uency band ..arent coverage performance may vary from 1 to 60 bit?s?>@?kmI, while pico cell technology can achieve from depending 100 on to the -00bit?s?>@?kmI, software.

same time, it is probable that the radio access network will evolve from a centrali@ed architecture to a distributed one. #echno'ogica' drivers7 Microprocessor performance

comple0ity of the terminal hardware and

increase #MooreJs law$ ,attery performance increase #a much slower e0ponential curve than MooreJs :aw$ #batteries are the big bottleneck$ 'ir interfaces with increasingly better spectral efficiencyK ,etter processor performance?power consumption ratio >andset display power consumption efficiency

<. ,6IVE6S

5 1&

%n the future, low cost, high speed data will drive forward the fourth generation #4G$ as 3hort&range communication emerges. 3ervice and application ubi/uity, with a high degree of personali@ation and synchroni@ation between various user appliances, will be another driver. 't the

=. 5E-#"6ES

5 1&
interactive internet,

3eamless on

switching, Luality of

3upport multimedia, voice,wireless video services.

variety of services based 3ervice#Lo3$ ,etter scheduling and call admission techni/ues 'd hoc and multi hop networks control

>igh speed, high capacity and low cost per bit. Global mobility, service portability and scalable mobile networks.

>. -PP!I+-#I $S
'lready at rates of 1-&+0 Mbps, 4G should be able to provide users with streaming high&definition television. 't rates of 100 Mbps, the content of a 8=8, for e0ample a movie, can be downloaded within about - minutes for offline access. "ew applications are as follows9 =irtual presence9 4G provides user services at all times, even if user is off site. =irtual navigation9 4G provides user with virtual navigation through which a user can access

a database of streets, buildings etc . Tele&geoprocessing9 information #Global /uerying. 4G can be used in Tele&medicine and education 7risis management9 natural disasters can cause breakdown in communication systems. %n today5s world it might take days or weeks to restore the system, but in 4G it is e0pected to restore such system$ this and 3ystem$ is a G.3 by combination of G%3 #Geographical .ositioning

which we can get location by

crisis issues in a few hours.

M 3ufficient spectrum, with associated sharing mechanisms. M 7overage with two technologies9 parent #6G, +G, iM'($ for real&time delivery, and discontinuous pico cell for high data rate delivery. M 7aching technology in the network and terminals. M E"8M and M%ME. M %. mobility. M Multi&technology distributed architecture. M "i0ed&mobile convergence #for indoor service$. M <etwork selection mechanisms. 7. !. 7asal, ". 3choute, and !. .rasald, F' novel concept for fourth generation mobile multimedia communication.G T. Ettosson, '. 'hlNen, '. ,runstrOom, M. 3ternad and '. 3vensson, FToward 4G %.&based wireless systems9 ' proposal for the uplink.G -th orld !esearch "orum. www.4gfeatures.com www.4gheterogeneousnetworks. com ireless

%?. + $+!"SI $
The provision of megabit?s data rates to thousands of radio and mobile terminals per s/uare kilometer presents several challenges. 3ome key technologies permit the progressive introduction of such networks without )eopardi@ing e0isting investment. 8isruptive technologies are needed to achieve high capacity at low cost, but it can still be done in a progressive manner. The key enablers are9 4G seems to be a very promising generation of wireless communication that will change the people5s life in wireless world. %t is e0pected to be launched by 6010 and the world is looking forward for the most intelligent technology that would connect the entire world. #hus we can conc'ude that using 1& conce)t the user has freedom and f'e@ibi'ity to se'ect any desired service with reasonab'e QoS and affordab'e )rice, anytime anywhere.

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