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The core to 4G

Mobile Communications

Luis Eduardo Snchez de Loera

Willie W. Lu, Jenny Hu

U.S. Center for Wireless

CommunicationsP.O.Box 19789, STANFORD

UNIVERSITY, CA 94309, USA


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Overview

Wireless Future - Evolution -> 3G

4G Mobile Technology

Motivation for 4G Research Before 3G Has Not Been Deployed?

Objectives

Approaches What is needed to Build 4G Networks of Future?

THE CREW: CURRENT R&D

Wireless Future -> Issues and Threats

Developments/ Industry Initiatives

Applications

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Introduction

Mobility is one of the most invigoratingfeatures, having an enormous impact on howcommunication is evolving into the future.

Mobility in 4G networks requires new level ofmobility support as compared to traditionalmobility.

This review aims to identify and explore thedifferent issues and challenges related tomobility management in 4G networks.

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0G

Half-duplex lines

One speaks, the other cannot speak.

Push-to-talk protocol (PTT)

Voice only

Two-way radio / Walkie-Talkies

Mobile Telephone System (MTS)

1946 MTS

1962 IMTS

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1G

Analog cell phones

Voice only

1980s to 1990s

NMT (Nordic Mobile Telephone)

AMPS (Advanced Mobile Phone System)

Problem with analog:

Not encrypted

Prone to distortions

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2G

1991 Digital networks

SMS

Mainly circuit-switched

Multiplexing: TDMA and CDMA

Standards: GSM, iDEN

1999 2.5G GPRS

Data rate up to 128 kb/s

EDGE Data rate up to 384 kb/s

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3G

Combines with IP based services Video-conferencing

Music downloading?

Transfer of data: Emails Documents

CDMA2000, UMTS, W-CDMA Problem:

Different places, different air interfaces Cost of deploying

Internet, e-mail, fax, e-commerce, music, video clips, andvideoconferencing

UMTS- UNIVERSAL MOBILE

TELECOMMUNICATION SYSTEM

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4G

Expected in 2010

Mobile multimedia, Anytime anywhere, Global

support, Integrated wireless solution,

Customized personal service

WiMAX

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Wireless Future - Evolution -> 3G (3rd

generation of mobile networks)

The Third Generation of mobile communicationssystems will soon be implemented.

Following on the heals of analog and digital

technology, the Third Generation will be digitalmobile multimedia offering broadband mobilecommunications with voice, video, graphics,audio and other information.

In fact, in countries such as Japan, South Koreaand Singapore 3G networks are already deployedand being used.

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Evolution of the Mobile Technologies

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What is 4G anyway?

4G refers to the next generation of wirelesstechnology that promises higher data rates and expandedmultimedia services.

The 4G is defined as a completely new fully IP-based integrated system of systems and network ofnetworks achieved after convergence of wired and wirelessnetworks as well as computers, consumer electronics, andcommunication technology and several other convergencesthat will be capable to provide 100 Mbps and 1 Gbps,respectively in outdoor and indoor environments, with end-

to-end QoS and high security, offering any kind of servicesat any time as per user requirements, anywhere withseamless interoperability, always on, affordable cost, onebilling and fully personalized.

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Generation Overview

Technology 1G 2G 2.5G 3G 4G

First design 1970 1980 1985 1990 2000

Implementation 1982 1991 1999 2002 2010?

Service Analog voice Digital voice,

SMS

Packaged data Broadband

data up to 2mb/s

IP-oriented

unlimitedmultimedia

data

Standards AMPS TDMA, CDMA,

GSM

GPRS, EDGE EV-DO,

W-CDMA,

HSDPA

WiMAX,

HSOPA

Data bandwidth 1.9 kbps 14.4 kbps 384 kbps 2 mbps 200 mbps


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Motivation for 4G Research Before 3G Has

Not Been Deployed?

3G performance may not be sufficient to meet needs of futurehigh-performance applications like multi-media, full-motion video,wireless teleconferencing. We need a network technology thatextends 3G capacity by an order of magnitude.

There are multiple standards for 3G making it difficult to roam and

interoperate across networks. we need global mobility and serviceportability

Difficulty in continuously increasing bandwidth and high data rateto meet multimedia services requirements, together with thecoexistence of different services needing different QoS.

We need wider bandwidth

We need all digital packet network that utilizes IP in its fullest formwith converged voice and data capability.

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Objectives

The 4G working group has defined the following as objectives ofthe 4G wireless communication standard:

A spectrally efficient system (in bits/s/Hz and bits/s/Hz/site)

High network capacity: more simultaneous users per cell

A nominal data rate of 100 Mbit/s while the client physically moves at high

speeds relative to the station, and 1 Gbit/s while client and station are inrelatively fixed positions as defined by the ITU-R

A data rate of at least 100 Mbit/s between any two points in the world

Smooth handoff across heterogeneous networks

Seamless connectivity and global roaming across multiple networks

Interoperability with existing wireless standards and

An all IP, packet switched networkIn summary, the 4G system should dynamically share and utilise

network resources to meet the minimal requirements of all the 4Genabled users.

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Principal Technologies

Baseband techniques[9]

OFDM: To exploit the frequency selective channel property

MIMO: To attain ultra high spectral efficiency

Turbo principle: To minimize the required SNR at the reception side

Adaptive radio interface

Modulation, spatial processing including multi-antenna and multi-user MIMO

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http://en.wikipedia.org/wiki/4Ghttp://en.wikipedia.org/wiki/4G


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Components - Access schemes

Recently, new access schemes like Orthogonal FDMA(OFDMA), Single Carrier FDMA (SC-FDMA), InterleavedFDMA and Multi-carrier code division multiple access (MC-CDMA) are gaining more importance for the nextgeneration systems.

WiMax is using OFDMA in the downlink and in the uplink.For the next generation UMTS, OFDMA is being consideredfor the downlink.

By contrast, IFDMA is being considered for the uplink sinceOFDMA contributes more to the PAPR related issues andresults in nonlinear operation of amplifiers.

IFDMA provides less power fluctuation and thus avoidsamplifier issues.

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Components IPV6

By the time that 4G is deployed, the process of IPv4address exhaustion is expected to be in its final stages.

Therefore, in the context of 4G, IPv6 support isessential in order to support a large number of

wireless-enabled devices. By increasing the number of IP addresses, IPv6

removes the need for Network Address Translation(NAT), a method of sharing a limited number ofaddresses among a larger group of devices.

In the context of 4G, IPv6 also enables a number ofapplications with better multicast, security, and routeoptimization capabilities.

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C t Ad d A t


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Components - Advanced Antenn

Systems

Transmitting & receiving antennas Resolve problem of diminishing spectrum availability Doesnt require increase power or additional frequency Fix no. of beams that can be selected to follow devices as it

moves about

Advantages: Increased capacity Increased range Less power use for transmission Reductions in handoff rate New services Increase security

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Components Software


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Components

Software-

Defined Radio (SDR)

SDR is one form of open wireless architecture

(OWA).

Since 4G is a collection of wireless standards,

the final form of a 4G device will constitute

various standards. This can be efficiently

realized using SDR technology, which is

categorized to the area of the radioconvergence.

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h i d d ild


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What is needed to Build

4G Networks of Future?

Lower Price Points Only Slightly Higher thanAlternatives

More Coordination Among Spectrum RegulatorsAround the World

More Academic Research

Standardization of wireless networks

A Voice-independent Business Justification

Thinking Integration Across Different Network Topologies

Non-disruptive Implementation

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THE CREW: CURRENT R&D

Alcatel, Ericsson, Motorola, Nokia, and Siemensfounded the Wireless World Research Forum (WWRF)in early 2001 (www.wireless-world-research.org).

That forum's objective is to formulate visions onstrategic future research directions for the wirelessfield.

The timeframe for these reflections is in the range of 7to 12 years from now. The main deliverables of the

WWRF are white papers on emerging-technologytopics and its seminal Book of Visions.

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Developments/ Industry Initiatives

The Japanese company NTT DoCoMo has been testing a 4Gcommunication system prototype with 4x4 MIMO called VSF-OFCDM at 100 Mbit/s while moving, and 1 Gbit/s while stationary.

Digiweb, an Irish fixed and wireless broadband company, hasannounced that they have received a mobile communications

license from the Irish Telecoms regulator, ComReg. Sprint plans to launch 4G services in trial markets by the end of

2007 with plans to deploy a network that reaches as many as 100million people in 2008 and has also announced WiMax servicecalled Xohm. Tested in Chicago, this speed was clocked at 100Mbit/s.

WWRF (Wireless World Research Forum)- consisting of Alcatel,Ericsson, Nokia and Siemens have started a research forum for 4G

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Applications

E-commerce

Business/Work

Private Life

Vehicular

Public Place

Entertainment

Education

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References

Janny Hu,Willie W. Lu ,Open Wireless Architecture -The Core to 4G Mobile Communications. In

Proceedings of ICCT, 2003.

Jawad Ibrahim (December 2002). "4G Features" (PDF).

Bechtel Telecommunications Technical Journal.Retrieved on 2007-03-26.

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THANK YOU

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