seminar 4g slides

8/3/2019 Seminar 4g Slides

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Fourth generation-

Wireless technology

PRESENTED BYT.ASHA

P.LAKSHMI

S.SHEELA


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AGENDA

Introduction Evolution of Data Standards

Features

Architectures Key Technologies required for 4g

Issues

Applications Conclusion

References


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FOURTH GENERATION

TECHNOLOGY

4G technology :

- A collection of technologies and

protocols aimed at creating fully

packet-switched networks optimized

for data

4G goals:

- 100 Mbpsspeed while moving

- 1 Gbpsspeed while stationary


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EVOLUTION OF DATA STANDARDS

Radio telephone system

Contained one central antenna towerper region

The central antenna required radiophones to have a powerfultransmitter, capable of transmitting

up to 50 miles, limiting number ofphones in a region

ZERO GENERATION MOBILESYSTEMS (0G)


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CONTD..

The 1G cellular telephone system

Divided cities into small cells

Allows extensive frequencyreuse across a city

Encompasses analog standardsintroduced in the 1980s

Replaced by 2G digital cell phones.

FIRST GENERATION CELLULARCOMMUNICATION (1G)


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CONTD..

2G digital technologies can be divided into

two standards:

TDMA (Time Division Multiple Access)

- GSM, iDEN, PDC

- Used in America, Europe and Japan

respectively

CDMA (Code Division Multiple Access)

- IS-95

- Used in the America and parts of

Asia

SECOND GENERATION (2G)


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CONTD..

Allows transfer of voice data and non-voice data over the same networksimultaneously

Less expensive Standards

W-CDMA: Wideband Code DivisionMultiple Access

EVDO: Evolution-Data optimized

THIRD GENERATION (3G)


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3G Vs 4G

Technology 3G 4G

Data Transfer Rate 3.1MB /sec 100MB/sec

Internet services Broadband Ultra Broadband

Mobile -TV Resolution Low High

Bandwidth 5 - 20 MHz 100 +MHz

Frequency 1.6- 2 GHZ 2

8 GHz

Network Architecture Wide Area Network Hybrid Network


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WHY MOVE TOWARDS 4G ?

Enhanced Mobile Gaming

Personal Media Repository

Integrated networks

Virtual Presence

Broadband Access in Remote

Locations


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FEATURES

Support for interactive multimedia,voice, streaming video, Internet, andother broadband services

IP based mobile system

High speed, high capacity, and lowcostperbit

Global access, service portability, andscalable mobile services

Seamless switching and a variety ofQuality of Servicedriven services

Better scheduling andcalladmissioncontrol techniques


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CONTD

Adhoc and multihop networks Better spectral efficiency.

Seamless network of multiple protocols

and air interfaces 4G will be allIP, look for 4G systems to

be compatible with all common network

technologies, including 802.11,

WCDMA, Bluetooth, and Hyper LAN


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WHAT IS NEEDED TO BUILD 4G IN

FUTURE?

Lower Price Points only Slightly Higher

than Alternatives

More coordination among Spectrum

Regulators Around the World More Academic Research

Standardization of wireless Networks

Voice Independent Business Justification

Thinking

Integration across different Network

Topologies


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IMPLEMENTATION USING 4G

IPbased infrastructure throughheterogeneous access technologies It is assumed to act as an adhesive for

providing global connectivity and mobility

among networks. It is compatible with, and independent of

the underlying radio access technology

IP networks are connectionless and

use the slots only when they havedata to send. Implies optimum usage of the available

bandwidth


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ARCHITECTURE IN PROSPECTS

End-to-End Service Architecture

Addresses vertical integration

scalability with innovation speed up

Helps service provider communicate

among them to create the complete

solutions that end customers require


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Service Middleware architecture comprisesof

User support layer

Consists of 4 sub-systems:

Personalization, Adaptation,Community and Coordination

Service support layer

Traditional middle ware

Network support layer Consists of three subsystems: Discovery &

Advertisement, Contract Notary and

Authentication & Authorization


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Cellular Multi hop Communications:Infrastructure-Based Relay NetworkArchitecture- Most promising architectural upgrade

-Signal from source reaches destination inmultiple hops through use of relays

- Relaying allows substituting poor-qualitysingle-hop wireless with composite two ormore hops giving better quality

- Extends high data rate coverage range ofsingle base station giving cost effectivecoverage


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ADVANTAGES - MUTIHOPS

Property owners can install their ownaccess points.

Reduced network access operational cost.

Ad hoc-like characteristics

Multihop also could reduce costs inheterogeneous 3G networks.


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Overlay Network: A virtual network implemented on top of

another for the purpose of performing a specificfunction

Purpose in 4g is to integrate variety of network

access methods

User accesses overlay n/w which consists ofseveral UAP (Universal Access Points)

UAP selects wireless n/w based on availability,

QoS specification, user defined choices UAP stores user , network, device information,

capabilities, preferences

Supports single billing and subscription


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Possible 4G wireless networkarchitectures.

(a) A multimode device lets the user,

device, or network initiate handoff

between networks without the need for

network modification or interworking

devices.

(b) An overlay network

consisting ofseveral universal access points (UAPs)

that store user, network, and device

informationperforms a handoff as

the user moves from one UAP to

another.

(c) A device capable of automatically

switching between networks is

possible if wireless networks can

support a common protocol to access

a satellite-based network and another

protocol for terrestrial networks.


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WIRELESS TECHNOLOGIES USED IN

4G

OFDM

UWB

MILLIMETER WIRELESS

SMART ANTENNAS LONG TERM POWER PREDICTION

SHEDULING AMONG USERS

ADAPTIVE MODULATION AND POWER

CONTROL


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ORTHOGONAL FREQUENCY

DIVISION MULTIPLEXING

OFDM Type of multi-carrier modulation

Single high-rate bit stream is converted to low-rate

N parallel bit streams

Each parallel bit stream is modulated on one of N

sub-carriers

Each sub-carrier can be modulated differently

To achieve high bandwidth efficiency, the

spectrum of the sub-carriers are closely spaced and

overlapped Nulls in each sub-carrier's spectrum land at the

center of all other sub-carriers (orthogonal)

OFDM symbols are generated using IFFT


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OFDM PRINCIPLES OFDM transmitter accepts data from IP networks

IFFT transfers OFDM signal into analog signal sent toRF transceiver

Receiver reconstructs data by reversing this process

With orthogonal sub-carrier, it can separate and

process each sub-carrier without interference

providing better link and communication quality


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ULTRA WIDE BAND (UWB) UWB transmitter spreads its signal over a wide

portion of the RF spectrum

Generally 1 GHz wide or more, above 3.1GHz

Distinct advantage of UWB is its immunity tomultipath distortion and interference

Muti-path propagation occurs when transmitted

signal takes different path from S to D

One part goes to receiver directly and thedeflected path reaches after a long time

This causes information symbol to overlap

causing inter-symbol interference ISI

The short time span of UWB eliminates this ISI

Useful for intrastructure and mobilecommunications applications, minimizing S/N

reduction and bit errors.


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MILLIMETER WIRELESS

Makes use of available region of bandwidthresources committed by the governments of

some countries to unlicensed cellular and

other wireless applications.

SMART ANTENNA Comprises of multiple antenna elements

Example: MIMO (MultiInput MultiOutput) MIMO represents SDMinformation

symbols multiplexed on spatially separated

N multiple antennas and received on M

antennas


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MIMO TEST SYSTEM

Multiple parallel channels that operate

simultaneously on the same frequency band and at

the same time

High spectral efficiencies in a rich scattering

environment (high multipath), since it can transmit

multiple data streams simultaneously


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LONG TERM POWER

PREDICTION

If Channel properties can be predicted a

number of milliseconds ahead, it would

be possible to distribute transmission

load among users Leads to optimal distribution of load

Taking this advantage, time-frequency

regions are predetermined

The time-frequency regions are allocated

to users using scheduling algorithms


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SCHEDULING AMONG USERS

Scheduling is done

To optimize the system throughput

under specified QoS requirements and

delay constraints At two different levels

Among sectors

Among Users


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ADAPTIVE MODULATION AND

POWER CONTROL

In a highly loaded system, modulation

format for the scheduled user is selected

according to the

predicted signal to noise and

interference ratio

For time frequency bins the optimum rate

and power allocation can be calculated

under a total average power constraint

Optimum strategy is to let the user with the

best channel transmit in each parallel

channels


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BASIC MODEL FOR 4G NETWORKS

Our focus is network layer in describingthe basic model

It is made up of two layers

Control plane

This performs control related actions suchas AAA, MIP registration, QoS signaling,installation/maintenance of trafficselectors and security associations, etc.,

Data plane This data plane is responsible for data

traffic behaviors (such as classification,scheduling and forwarding) for end-to-endtraffic flows.


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ISSUES

Issues in 4G:

Optimal choice of access technology

Design of a mobility enabled IP

networking architecture

Adaptation of multimedia

transmission across 4G networks


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MOBILITY MANAGEMENT

Features in mobility management:

128 bit address

High quality for audio/video,

short/bursty connection, peer-to-peerapplication

Fast packet delivery, decreased cost

Smooth handoff


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QUALITY OF SERVICE

Internet provides users with diverseand essential quality of service (QoS)

Handover technology

Handover latency Two technologies paving the way for

tomorrows QoS:

MPLS

Differentiated Services


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QoS SUPPORT

QoS support can occur at five different

levels :

Packet level

Transaction level Circuit level

User level

Network level


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SECURITY

IETF protocol - a flexible frameworkfor extensible network access

authentication & potentially could be

useful.

AAA protocols provides framework

for control plane function with

security policies such as encryption

and decryption. Dynamic reconfigurable and light

weight security mechanisms are used.


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APPLICATIONS

Categories in which services andapplications are being used:

Localized/Personalized information

services Communication services

Organizational services

Entertainment services

Tele Geo-Processing

Virtual Navigation


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CONCLUSION

History of mobile communications shows

attempts to achieve a single global

standard.

4G systems promises this achievementwith the concept of integration.

4G promises to fulfill the goal of PCC

(Personal Computing and Communication)


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CONCLUSION

4G wireless technology offers

higher bit rates

the ability to roam across multiple

heterogeneous wireless networks However the issues in 4g technology

require further research and

development.


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REFERENCES

1. e-mobility Technology PlatformWhitepaper edited by Didier Bourse(Motorola Labs) and Rahim Tafazolli(University of Surrey, CCSR)

2. Intuitive Guide to Principle of

Communications copyright 2004Charan Langton

3. Paper on 4g evolution By Abhijit Hota

4. www.wikipedia.com

5. www.4gco.uk6. www.wiley.com

7. www.mobilecommtechnology.com

8. www.uscwc.com


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Thank you

seminar 4g slides

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