4Generation mobille

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4G cellular WirelessTechnology

Subrata SahaRoll No : 09123114007


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Previous Technology - 1G FirstGeneration Analog

- Continuous in amplitude and time

- Variations in the signal - disrupts over long distances

Average between 4,800 to 9,600 bps (bits per second)

Simplest type to wireless data


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2G Technology


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Previous Technology - 2G- Digital data can be compressed and multiplexed much more

effectively than analog voice encodings

Multiplexing - multiple analog message signals or digitaldata streams are combined into one signal


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Previous Technology - 2G Advantages

- The digital voice encoding allows digital errorchecking

increase sound quality lowers the noise level

- Going all-digital allowed for the introduction of

digital data transfer SMS - short message serviceE-mail


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Previous Technology - 2G Disadvantages

- Cell towers had a limited coverage area Jagged Decay curve

-Abrupt dropped calls-Analog - gradual sound reduction

Spotty coverage


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Previous Technology - 3G Large capacity and broadband capabilities

Allows the transmission of 384kbps for mobile systems and up to2Mbps Increased spectrum efficiency - 5Mhz

- A greater number of users that can be simultaneouslysupported by a radio frequency bandwidth

- High data rates at lower incremental cost than 2G- Global roaming


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Previous Technology - 3G CDMA - Code Division Multiple Access

- Form of multiplexing- Does not divide up the channel by time or frequency- Encodes data with a special code associated with eachchannel


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Frequency Division Multiple Access Time Division Multiple Access

Code Division Multiple Access

Frequency


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Reasons for New Research Even though 3G has successfully been introduced to

mobile users, there are some issues that are debatedby 3G providers and users.

- High input fees for the 3G service licenses

- Great differences in the licensing terms

- Current high debt of many

telecommunication companies, making it more of achallenge to build the necessary infrastructure for3G


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Reasons for New Research

Government are forced to

support to the financiallytroubled operators

3G phones are expensive Lack of 2G mobile user buy-in

for 3G wireless service

Lack of coverage because it is

still a new service- i.e. Champaign-Urbana uses

2.5G

- Chicago is 3G equipped


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Evolution to Fourth Generation systems


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4G Technology


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What is 4G?

Fourth Generation Technology Faster and more reliable

-100 Mb/s (802.11g wireless = 54Mb/s, 3G = 2Mb/s) Lower cost than previous generations

Multi-standard wireless system

- Bluetooth, Wired, Wireless (802.11x)

Ad Hoc Networking

IPv6 Core OFDM used instead of CDMA Potentially IEEE standard 802.11n

- Most information is proprietary


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Communications Architecture

Broadcast layer: fix access points, (ie celltower) connected by fiber, microwave, orsatellite (ISP)

Ad-hoc/hot-spot layer: wireless LANs (ie.internet at Starbucks)

Personal Layer Gateway: devices thatconnect to upper layers; cell phone, fax,

voice, data modem, MP3 players, PDAs

Info-Sensor layer: environmental sensors Fiber-optic wire layer: high speed

subterranean labyrinth of fiber optic cables

and repeaters


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Ad Hoc Networks Spontaneous self organization of networks of devices Not necessarily connected to internet

4G will create hybrid wireless networks usingAd Hoc networks

Form of mesh networking -Very reliable


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Smart Antennas Beam radio signals directly at a user to follow the user as

they move

Allow the same radio frequency to be used for otherusers without worry of interference

Cant keep up transmission speeds while device ismoving fast (i.e. in a car)

- Only 32Mb/s at 62mph (vs 100Mb/s)

Seamless handoff between towers/access points One transmit antenna, two receive antennas

- Allows connection to two access points at once


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Mobile IPv6

More addresses than current version of IP protocol(Version 4) each device can have own IP

- Keep IP address even if you change access point- Presently translate IP with each change because notenough IP addresses to go around

IP Core - everything can talk to each other if they speakthe same language (protocol)

IPv6 Source Address Destination AddressPacket

DATA (1011101001010)


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IP Core


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Mobile VoIP

Voice Over Internet Protocol

Allows only packets (IP) to be transferred, eliminatingcomplexity of 2 protocols over the same circuit

All voice data will be wrapped up in a packet- lower latency data transmission (faster transmission)

Samples voice between 8,000 & 64,000 times per secondand creates stream of bits which is then compressed and

put into a packet. Increases battery life due to greater data compression

10011101101 IP(10011101101)

Voice Compressed bit stream IP packet


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OFDM

Orthogonal Frequency Division Multiplexing

Allows for transfer of more data than other forms of

multiplexing (time, frequency, code, etc)

Simplifies the design of the transmitter & receiver

Allows for use of almost the entire frequency band

- No gaps to prevent interference needed

Currently used in WiMax (802.16) and Wi-Fi (802.11a/g)


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How OFDM Works

Bit = 1 0 1 0 1 1 0 0

Above, binary phase shift keying (BPSK). Thephase of the sin wave changes to represent adifferent bit.


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How OFDM works Frequency of the previous wave


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How OFDM works The frequencies are spaced so that the signals do not

interfere with each other (no cross talk)

Parallel Data Transmission - Allows for the sending ofmultiple signals simultaneously from the same antenna (orwire) to one device

- Each transmission has a different stream of bits


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Impact of 4G


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Socio-Economic Impact

More affordable communication services One device can communicate with all vs. many

devices communicating with some devices

TV, internet, phone, radio, home environment sensors allreachable through one device the cell phone

- Streaming HD video

Too connected?

- Increase in social networking, invasion of privacy,security concerns

- Increase in regulation likely (ie. no driving and using acell phone)


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When?

China Mobile, KPN, NTT DoCoMo, Orange, Intel,

Motorola, Sprint Nextel, T-Mobile and Vodafone alreadydoing research on 4G

Much of this information is proprietary at this time Expected release of 4G services as early as 2008. Majority of companies expect widespread use of 4G

systems by 2010.

Lifecycle of 4G is estimated to be 15 years.


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4Generation mobille

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