3G

3G3G3G3G

PresentationPresentationOn On

33rd rd Generation Generation Mobile CommunicationMobile Communication

PresentationPresentationOn On

33rd rd Generation Generation Mobile CommunicationMobile Communication

3G3G3G3G3G: What’s the hype all about ?

Emerging user demands to shift from voice centric to multimedia-oriented services (voice, data, video, fax)

Until recently, data traffic over mobile networks remained low at around 2% due to the bandwidth limitations of 2G wireless networks.

New technology required for optimal transport and higher bandwidth.

3G3G3G3GGSM Technology

Before talking about 3G We will discuss about mobile communication

3G3G3G3GHome location Reg

Visitor location Reg

Equip. Id Reg

Auth

3G3G3G3GGSM Services -Voice Services -Data Services -Multicast Services -Short Messaging Services

-Location Based Services (LBS)

GSM Products (Mobile Devices) -Subscriber Identity Module (SIM) -Mobile Telephones -PCMCIA Air Cards -Embedded Radio Modules -External Radio Modems

GSM-900:Uplink: 890.2 MHz – 915 MHz (25 MHz)Downlink: 935.2 MHz – 960 MHz (25 MHz)

GSM - Frequencies GSM-1800:Uplink: 1725.2 – 1780.4 MHz

Downlink:1820,2 - 1875,4 MHzSeparation: 95 MHz384 pairs of channels

3G3G3G3GGSM Network -Base Stations, Repeaters, Switching Centers -Network Databases Wireless Network System Interconnection , Customized Applications for Mobile Network Enhanced Logic.

3G3G3G3GSIM - Subscriber Identity Module, ME - Mobile Equipment,

BTS - Base Transceiver Station, BSC - Base Station Controller,

TCU - Transcoder Unit, MSC - Mobile Switching Centre,

PSTN - Public Switched Telephone Network,

HLR - Home Location Register, VLR - Visitor Location Register,

AUC - Authentication Centre, EIR - Equipment Identity Register,

OMC - Operations & Maintenance Centre,

OMC-R - OMC devoted to BSS, OMC-S - OMC devoted to NSS.

3G3G3G3GBase Station Sub-system (BSS)

The Base Station function is divided into two main functional elements, the Base Station Controller (BSC) which also includes the Transcoder Unit (TCU), and the Base Transceiver System (BTS).

The BSC can control several BTS units. Each BTS will consist of a number of transceivers (TRX) and will serve a cell or a number of cells. The BSC unit also performs transcoding functions to convert between 64Kbps channel rate used in the Switching System and the 16Kbps channel rate for GSM traffic.

3G3G3G3GThe OMC provides remote monitoring of the network performance

and permits remote re-configuration and fault management activity

as well as alarm and event monitoring.

Mobile Station (MS)

The MS comprises of Mobile Equipment (ME) and a Subscriber Identity

Module (SIM). The ME contains the software and hardware to operate

as a mobile radio terminal. The SIM in conjunction with the network

Authentication Centre (AUC) validates the MS.

UMTS Network Architecture

One of the requirements for the Release 99 Architecture is to

support roaming and inter-operation with the GSM system,

hence the GSM system appears as one of the components

of the UMTS Release 99 Architecture.

Operation Sub-System (OSS)

3G3G3G3GExisting Mobile N/WsExisting Mobile N/Ws

First Generation wireless technology, AMPS in North America

and TACS in Europe based on circuit switched technology.

2G based on low band digital data signaling, most popular

technology being GSM, a combination of FDMA and TDMA, mostly in

Europe.

2G systems can handle some data capabilities at the

rate up to 9.6 kbps

2G+ packet based and increases the data communication speed

to as high as 384 kbps, based on GPRS,HSCSD and EDGE terminals.

3G3G3G3G

Tech 1G 2G 2.5G 3G

Design began

1970 1980 1985 1990

Impleme-ntation

1984 1991 1991 2002

service Analogue voiceSynchronousdata upto 9.6Kbps

Digital voice Shortmessage

Higher capacity,Packetis

ed data

Highercapacity,broadband

dataUpto 2Mbps

Standards AMPS. TACS,NMT etc

TDMA,CDMA,GSM,PDC

GPRS,EDGE

WCDMA,CDMA

3G3G3G3GData BW 1.9Kbps 14.4 Kbps(9.6) 384Kbps(50) 2Mbps

128Kbps in mobile

MUX FDMA TDMA,CDMA TDMA,CDMA CDMA

Core N/W PSTN PSTN PSTN,PACK

ET N/W

Packet N/W

Support GSM GSM(EUROPE)

TDMA,CDMA

(AMERICA)

GSM,GPRS,E

DGE

GSM,GPRS,EDGE,CD

MA,TDMA

BW 800-900Mhz. 1850-1990Mhz For use ,text, digital

data, voice,

multimedia Other non

global roaming

Accessibility through

tetra & satellite

3G3G3G3GAir Interfaces for Third Generation services:

USA plans to deploy EDGE, WCDMA and multi carrier CDMA in the existing bands used by second-generation systems. Europe plans to use IMT-2000 Band for WCDMA and EDGE for GSM 1800 bands.

Asia is expected to utilize IMT-2000 Band for WCDMA and GSM 1800 band for EDGE. Korea is expected to utilize IMT-2000 Band for WCDMA. Japan plans to deploy IMT-2000 band for WCDMA.

3G3G3G3G3G Networks

Consists of following air interface modules: WCDMA,CDMA2000 interfaces. WCDMA compatible with current 2G GSM networks, requires bandwidth between 5 and 10 MHz, can be overlaid into existing GSM,TDMA and IS95 networks.

CDMA2000 backward compatible with the second generation CDMA IS-95 predominantly used in US UWC-136, also called IS-136HS was designed to comply with ANSI-136, the North American TDMA standard.3G network constitution

-consists of a Radio Access Network (RAN) and a core network

-core network consists of a packet switched domain whichincludes 3G SGSNs and GGSNs.

-core network consists of a circuit switched domain which includes 3G MSC for voice calls.

3G3G3G3G3G networks (contd.)3G networks (contd.)

core network also consists of a CGF

(Charging Gateway function) to charge

for services and access. RANs consist of

new n/w elements, known as Node B

and Radio Network Controllers (RNCs)

Node B is comparable to BTS in 2G

systems.RNCs replace the BSCs. It

provides the radio resource

management, handover control and

support for connection to packet as

well as circuit switched domains.

3G3G3G3G

or moving at pedestrian speed, 128 Kbps in

a car, and 2 Mbps in fixed applications. 3G

will work over wireless air interfaces such as

GSM, TDMA, and CDMA. The new EDGE

air interface has been developed specifically

to meet the bandwidth needs of 3G.

3G is an ITU specification for the third generation of mobile communications technology. 3G promises increased bandwidth, up to 384 Kbps when a device is stationary

3G3G3G3G

3G3G3G3G3G Network Components3G Network Components

1. Radio Access Networks (RANs)2. W-CDMA uses the 2GHz frequency band, can reach

data transfer speeds of upto 2 Mbit/s but in reality transfer speed is closer to a couple of hundred kbit/s the actual bit rate depending on cell load and user mobility.basic modes of operation(FDD and TDD) with paired and unpaired bands respectively defined as follows.

3. FDD. Uplink and downlink transmissions use two different carriers located in specific frequency bands. Users using the same carrier sets are distinguished by different spreading codes.

3G3G3G3G3G Terminals3G Terminals-will be multi-mode i.e. be able to support more than one

- radio system

- current terminals are multi band e.g. GSM dual band

that is they can handle different frequency bands but not

different radio systems.

- 3G terminals need to be both dual mode and dual band.

-they would have a GSM call control stack, session

management and radio interface implemented together

with the corresponding UMTS terminal functionality.

3G3G3G3G

Technology

3G3G3G3G

Umts architectureUmts architecture

UMTS • Uplink: 1920 - 1980MHz • Downlink: 2110 - 2170MHz

UMTS - Applications• Fast Internet / Intranet• Streaming / Download (Video, Audio)• Videoconferences• Multimedia-Messaging, E-Mail• Mobile E-Commerce (M-Commerce)• Location Based Services• Mobile Entertainment (Games,…)

3G3G3G3GGPRS

The GPRS Core Network (General Packet Radio

Services) provides mobility management, session management

and transport for Internet Protocol packet services in GSM

and UMTS networks

The first new technology when going from GSM

towards UMTS is General Packet Radio Service (GPRS).

It is the trigger to 3G services. The main point is that the

network connection is always on, so the subscriber is

online all the time.

3G3G3G3G

Serving GPRS Support Node

3G3G3G3GGPRS Tunnelling Protocol is the defining IP protocol of the GPRS core

network. Primarily it is the protocol which allows end users of a GSM or

UMTS network to move from place to place whilst continuing to connect

to the internet as if from one location at the GGSN. It does this by

carrying the subscriber's data from the subscriber's current SGSN to the

GGSN which is handling the subscriber's session.

3G3G3G3GGGSNs and SGSNs (collectively known as GSNs) listen for messages

on UDP port 2123 and for GTP-U messages on port 2152. This

communication happens within a single network or may, in the case of

international roaming, happen internationally, probably across a

GPRS Roaming Exchange (GRX)

GPRS Support Nodes (GSN)

A GSN is a network node which supports the use of GPRS in the GSM

core network. All GSNs should have a Gn interface and support the GPRS

tunnelling protocol. There are two key variants of the GSN; the GGSN and

the SGSN defined

3G3G3G3GGGSN - Gateway GPRS Support Node

The GGSN is the interface between the GPRS data network and

external Packet Data Networks (PDN) such as the Internet. From an

external IP networks point of view, the GGSN acts as a router for

the IP addresses of all subscribers served by the GPRS network.

The GGSN therefore exchanges routing information with the

external network.

SGSN - Serving GPRS Support Node

The SGSN is the interface between the base station subsystem and

the data network. It is responsible for delivery of packets within its

own service area. The SGSN routes packets through the base

station controller and also signals the mobile switching centre,

home location register and visitor location register.

3G3G3G3GCommon SGSN FunctionsDe-tunnel GTP packets from the GGSN (downlink)

Tunnel IP packets toward the GGSN (uplink)

Carry out mobility management as Standby mode mobile

moves from Routing Area to Routing Area.

Billing user data

3G3G3G3GInternational Mobile Telecommunications-2000 (IMT-

2000) are third generation mobile systems which was scheduled to start service subject to market considerations.

They will provide access, by means of one or more

radio links, to a wide range of telecommunications services

supported by the fixed telecommunication networks, and to

other services which are specific to mobile users.

A range of mobile terminal types is encompassed,

linking to terrestrial and/or satellite based networks, and the

terminals may be designed for mobile or fixed use.

IMT-2000

3G3G3G3GKey features of IMT-2000 are: • high degree of commonality of design worldwide; • compatibility of services within IMT-2000 and with the fixed

networks; • high quality; • small terminal for worldwide use; • worldwide roaming capability; • capability for multimedia applications, and a wide range of

services and terminals. • IMT 2000 is a result of the collaboration of many entities, inside

the ITU (ITU-R and ITU-T), and outside the ITU

(3GPP, 3GPP2, etc.)

3G3G3G3GThe IMT-200 vision encompasses

complementary satellite and terrestrial

components.

Close integration between the satellite and

terrestrial components of IMT-2000 facilitate the

deployment of mobile services via satellite,

enabling users to roam on satellite networks and

to gain access to service where there is no

terrestrial system in place.

3G3G3G3G--they would have to be multi-mode to support

global roaming i.e. to be able to handle the W-CDMA

and CDMA2000 modes.

-support for the 2 W-CDMA modes FDD and TDD is

something which needs to be considered.

-This is because it is more difficult to build wide area

coverage with TDD, but easier to cater to asymmetric

traffic than it is with FDD mode. So operators might

choose to use FDD for outdoor service and TDD for

indoor service.

3G3G3G3GInternational Telecommunications Unit (ITU): IMT-2000 consists of following radio interfaces

•W-CDMA •CDMA2000 •CDMA2001 •TD-CDMA / TD-SCDMA

GSM 850MHz GSM 900MHz GSM 1800MHz GSM 1900MHz CMDA 800MHz CDMA 1900MHz CDMA 2100MHz UMTS 800MHz UMTS 850MHz UMTS 900MHz UMTS 1800MHz UMTS 1900MHz UMTS 2100MHz iDEN 800MHz iDEN 900MHz PHS TDMA FDMA

Networks versus Standards : Cellular Networks:

3G3G3G3GCSD HSCSD GPRS EDGE UMTS CDMA2000 1x CDMA2000 1xEV-DV CDMA2000 1xEV-DOWCDMA FOMA

Cellular Data Standards:Cellular Data Standards:

Even though 3G has successfully been introduced to European Even though 3G has successfully been introduced to European and Asian mobile users, there are some issues that are debated and Asian mobile users, there are some issues that are debated by 3G providers and users:by 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 a challenge to build the necessary infrastructure for 3G •Member State support to the financially troubled operators •Health aspects of the effects of electromagnetic waves

3G3G3G3G

The main principle of Spread Spectrum communication is that the bandwidth occupancy is much higher than usual.

Because of this much larger bandwidth the power spectral density is lower, in the channel the signal just looks like noise.

The Spreading is done by combining the data signal with a code (code division multiple access) which is independent of the transmitted data message.

Spread Spectrum communication

3G3G3G3G•Direct-Sequence (DS) •Frequency-Hopping (FH).

Direct Sequence is the most famous Spread Spectrum Technique. The data signal is multiplied by a Pseudo Random Noise Code (PN-code).

Frequency HoppingWhen using Frequency Hopping, the carrier frequency is

'hopping' according to a known sequence (of length ). In this way the bandwidth is also increased. Frequency Hopping is a from of spread spectrum in which spreading takes place by hopping from frequency to frequency over a wide band.

A combination of these two offers a lot of advantages over the other two and will be the basis of the proposed system.

Spread Spectrum Techniques

3G3G3G3GThe main principle of Spread Spectrum

communication is that the bandwidth occupancy is much

higher than usual.

Because of this much larger bandwidth the power

spectral density is lower, in the channel the signal just

looks like noise.

The Spreading is done by combining the data

signal with a code (code division multiple access)

which is independent of the transmitted data message.

3G3G3G3GAs the signal is spread over a large frequency-band, the

Power Spectral Density is getting very small, so other

communications systems do not suffer from this kind of

communications.

Random Access can be dealt with, as a large number of codes

can be generated a large number of users can be permitted.

The maximal number of users is interference limited.

Security: without knowing the spreading code, it is (nearly)

impossible to recover the transmitted data.

Fading rejection: as a large bandwidth is used the system is

less susceptible to distortions.

A number of advantages are:

3G3G3G3GWCDMA (Wideband Code Division Multiple Access) is

the radio access scheme used for third generation cellular

systems that are being rolled out in various parts of the globe.

The 3G systems to support wideband services like high-

speed Internet access, video and high quality image

transmission with the same quality as the fixed networks. In

WCDMA systems the CDMA air interface is combined with

GSM based networks.

The WCDMA standard was evolved through the Third

Generation Partnership Project (3GPP) which aims to ensure

interoperability between different 3G networks.

3G3G3G3GEnhanced Data rates for Global Evolution

(EDGE) is a radio based high-speed mobile data standard. It allows data transmission speeds of 384 kbps to be achieved when all eight timeslots are used.

EDGE, Enhanced Data GSM Environment

EDGE enhances the throughput per timeslot for both HSCSD and GPRS. ECSD (max data rate 64 kbps and EGPRS data rate per time slot triples to a staggering 384 kbps.

3G3G3G3GFrom GPRS, operators could go directly to UMTS, but they

could also invest in an EDGE system. One advantage of EDGE is

that there is no new licence needed as in UMTS. The frequencies

will also be re-used and no new antennas are needed. The main

issue is that subscribers will have to buy new EDGE terminals.

From GSM radio network, the following network elements can

NOT be reused. Note, however they can remain in the network and

be used in dual network operation where 2G and 3G networks co-

exist while network migration and new 3G termials become

available for use in the network.•BSC (base station controller) •BTS (base transceiver station)

3G3G3G3GWide band CDMA (W-CDMA)

W-CDMA, also known as CDMA Direct Spread, is a 3G radio transmission technology favored by Europe. It can be built upon existing GSM networks and represents the obvious next step for current system operators. As such, it is expected to gain widespread acceptance in Asia, where GSM systems are prevalent.

cdma2000Also called CDMA Multi-Carrier, cdma2000 is a 3G standard developed by the CDMA Development Group (CDG) and favored by the U.S. It is derived from the narrow band CDMA One digital standard and provides a clear evolutionary path for existing CDMA One operators.

3G3G3G3G2G+ networks2G+ networks

HSCSD one step towards 3G wideband mobile data networks. This

circuit switched technology improves data rates up to 57.6 kbps.GPRS

packet based and designed to work in parallel with 2G GSMand TDMA

technologies.

Protocols in the GPRS network infrastructureProtocols in the GPRS network infrastructure

Sub-Network Dependent Convergence Protocol (SNDCP)

Logical Link Control (LLC)

Base Station System GPRS Protocol (BSSGP)

GPRS Tunnel Protocol (GTP)

GPRS Mobility Management (GMM/SM)

3G3G3G3G3G is short for third-generation technology. It is used in the context of mobile phone standards.

The services associated with 3G provide the ability to transfer simultaneously both voice data (a telephone call) and non-voice data (such as downloading information, exchanging email, and instant messaging).

In marketing 3G services, video telephony has often been used as the killer application for 3G.

3G3G3G3GWorldwide roll-out of 3G networks was delayed in

some countries by the enormous costs of additional spectrum licensing fees. In many parts of the world 3G networks do not use the same radio frequencies as 2G, requiring mobile operators to build entirely new networks and license entirely new frequencies

The license fees in some European countries were particularly high, bolstered by initial excitement over 3G's potential. Other delays were as a result of the expenses related to upgrading equipment for the new systems.

3G3G3G3GJapan and South Korea were relatively quick

to adopt 3G, because their governments prioritize

technological infrastructure development, and spectrum

licensing fees are minimal.

The first country which introduced 3G on a

large commercial scale was Japan. In 2005, about

40% of subscribers used 3G networks only, with 2G

being on the way out in Japan. It was expected that

during 2006 the transition from 2G to 3G would be

largely completed in Japan, and upgrades to the next

3.5G stage with 3 Mbit/s data rates were underway.

3G3G3G3GThe official 3G mobile network is the systems and

services based on the ITU family of standards under the

International Mobile Telecommunications programme,

'IMT-2000'.

The most significant features offered by third

generation (3G) mobile technologies are the momentous

capacity and broadband capabilities to support greater

numbers of voice and data customers - especially in

urban centres - plus higher data rates at lower

incremental cost than 2G.

3G3G3G3G•Expense and bulk of 3G phones •Lack of 2G mobile user buy-in for 3G wireless service •Lack of coverage because it is still new service •High prices of 3G mobile services in some countries, including Internet access

3G3G3G3G3G handsets are far more advanced and have much more functionality than conventional 2G handsets. 3G handsets usually include cameras, music players, video players, contactless smartcards for payment functions (wallet phones), web browsers, email clients and more. This shows that UMTS system is based on layered services and future applications can be supported without too much impact to the underlying radio access network.

3G3G3G3GUse of 3G

Checking traffic conditions from home and on the road to help plan route and allocate traveling time; alerting the driver if there is an accident, and suggesting an alternate route.

Directory services - enhanced wireless devices will allow users to find the nearest theatre, buy the tickets electronically, and download e-tickets at the theatre.

Booking travel reservation on-line - booking a tour, checking on scheduled flights to make sure they are on time, checking itinerary, changing flight plans if a connection is missed and booking a hotel.

News - all types of information for various purposes, for example, business managers looking for the latest information about their companies, and stock traders checking news developments that might affect their portfolios.

3G3G3G3GWLAN vs. 2G/3G: Bit rates

IEEE 802.11 WLAN

GPRS

3G (WCDMA)

170 kbit/s theoretically

Up to 2 Mbit/s (in indoor etworks)

Hundreds of meters (at best) around each AP

Full outdoor coverage is difficult to achieve.

WLANs are optimised for indoor usage.

Macro/micro/picocell networks cover all kinds of environments (indoor, urban, rural)

Full coverage even in remote areas.

3G3G3G3GWLAN vs. 2G/3G:WLAN vs. 2G/3G: Frequency bandsFrequency bands

IEEE 802.11 WLAN 2G/3G

The 2.4 GHz ISM band (free for all) causes problems.

Interference from other WLAN networks, Bluetooth equipment, microwave ovens, etc.

Frequency bands are reserved for 2G/3G networks.

Interference is usually not a problem (good network planning).

The CSMA/CA access method is not very spectrum efficient.

Spectrum efficiency is given as

bits/Hz/area

Spectrum efficiency is better than for WLAN.

Various advanced methods for increasing spectrum efficiency.

3G3G3G3GWLAN vs. 2G/3G:WLAN vs. 2G/3G: RoamingRoaming

IEEE 802.11 WLAN

2G/3G

WLANs do not support roaming in a strict sense.

However, WLANs support portability.

International roaming agreements between operators

2G/3G networks support roaming on a wide scale.

Terminal mobility is not supported (exceptwhen moving within the WLAN).

Terminal mobility is supported (using techniques such as location updating, paging, and handover).

Personal mobility requires e.g. SIP (Session Initiation Protocol) and specialised network resources (SIP

proxy, location server)

3G3G3G3GWLAN vs. 2G/3G:WLAN vs. 2G/3G: SecuritySecurity

IEEE 802.11 WLANIEEE 802.11 WLAN 2G/3G2G/3G

No security as default.

WEP (if used) offers poor security.

WPA (if used) provides better security due to the support of key management.

Always supported:

User authentication

Encryption over the radio interface

Key management.

3G provides additional security features.

Usually no network planning (due to the inexpensive network parts).

This (+ usage of ISM band) may result in poor WLAN network performance.

Network planning is rather complicated (since equipment is expensive and should not be underused).

As a benefit => good coverage and spectrum utilisation.

3G3G3G3GWLAN vs. 2G/3G:WLAN vs. 2G/3G: Cost of equipmentCost of equipment

IEEE 802.11 WLAN

2G/3G

Network infrastructure is inexpensive (existing LAN + additional APs) if no advanced network concepts are used.

End user equipment is also inexpensive.

Network infrastructure is expensive.

2G/3G terminals are not dramatically more expensive than WLAN cards.

Charging solutions are difficult to implement (specialised network elements required).

WLAN users are used to having “free” access in many places.

Charging is part of the system infrastructure.

Without charging, the expensive 2G/3G network infrastructure would not be economically viable.

3G3G3G3GServices: Web browsing

Web browsing applications are of client - server type. 802.11 WLAN and 2G/3G networks are equally well suited for such applications (disregarding differences in bitrates, coverage, etc.).

WebserverTerminal

= Client

1

2

http request

html page download

3G3G3G3GServices: VoIP

If reachability is an important issue, a client - client type of communication system requires some IP layer or application layer mobility solution => new network elements are required both in 2G/3G and in WLAN.

Terminal = Client

IP network(s)

Terminal = Client

3G3G3G3GWhat is 4G? 4G is the next generation of wireless networks that will replace 3G networks sometimes in future. In another context, 4G is simply an initiative by academic R&D labs to move beyond the limitations and problems of 3G which is having trouble getting deployed and meeting its promised performance and throughput.

3G3G3G3G1. 3G performance may not be sufficient to meet needs of

future high-performance applications like multi-media, full-motion video, wireless teleconferencing. We need a network technology that extends 3G capacity  by an order of magnitude. 

2. There are multiple standards for 3G making it difficult to roam and interoperate across networks. we need global mobility and service portability

3. 3G is based on primarily a wide-area concept. We need hybrid networks that utilize both wireless LAN (hot spot) concept and cell or base-station wide area network design. 

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

3G3G3G3G4.We need wider bandwidth

5.Researchers have come up with spectrally more

efficient modulation schemes that can not be

retrofitted into 3G infrastructure

6.We need all digital packet network that utilizes

IP in its fullest form with converged voice and

data capability.

3G3G3G3GRising use

As prices get more attractive, more and more people will

use wireless networks for data applications. Consequently,

bandwidth demand will rise.

Multimedia content

Mobile Social Networks

Voice over IP

Fixed line Internet replacement

Competition from alternative wireless Internet providers

3G3G3G3G

First of all, more bandwidth will be required

Secondly, 4G networks will no longer have a circuit switched

subsystem as current 2G and 3G networks. Instead, the network

is based purely on the Internet Protocol (IP). The main challenge

of this design is how to support the stringent requirements of

voice calls for constant bandwidth and delay.

Having sufficient bandwidth is a good first step. Mobility and

Quality of Service for a voice connection is clearly another and

taking a look at these topics is better left to another article

series. So let’s focus on the additional bandwidth 4G networks

are to deliver

There are two main goals of 4G wireless systems.

3G3G3G3G4G N/W will go far beyond this by mainly

improving three things Air Interface Technology: 2G networks use (TDMA) on the air interface.

3G networks made a radical change and use CDMA.

4G standards will make another radical change and will use OFDM. The

new modulation itself will not automatically bring an increase in speed

but very much simplifies the following two enhancements:

Channel BW: 2G systems use a channel bandwidth of 0.2 MHz. UMTS

made a great leap forward and uses 5 MHz. 4G systems will use a BW

of up to 20 MHz, i.e. the channel offers four times more bandwidth than

channels of current systems. As 20 MHz channels might not be

available everywhere, most 4G systems will be scalable, for example in

steps of 1.25 MHz. It can therefore be expected that 4G channel sizes

will range from 5 to 20 MHz.

3G3G3G3GMIMO:

The second method to increase throughput on the air

interface is to use a technology called Multiple Input Multiple

Output, or MIMO for short. The idea itself is simple, the maths

behind is everything but.

The idea of MIMO is to use the phenomena that radio

waves bounce of objects like trees and buildings and thus

create several wave paths from sender to receiver. While this

behavior is often not desired, MIMO makes active use of it by

using several antennas at the sender and receiver side, which

allows the exchange of multiple data streams, each over a

single individual wave front.

Two or even four antennas are foreseen to be used in a

device. How well this works is still to be determined in practice

but it is likely that MIMO can increase throughput by a factor of

two.

3G3G3G3G

Major Requirement Driving Architecture 

Predominantly voice driven - data was always add on

Converged data and voice over IP

Network Architecture

Wide area cell-basedHybrid - Integration of Wireless LAN (WiFi, Bluetooth) and wide area

Speeds 384 Kbps to 2 Mbps 20 to 100 Mbps in mobile mode

Frequency BandDependent on country or continent (1800-2400 MHz)

Higher frequency bands (2-8 GHz)

Bandwidth 5-20 MHz 100 MHz (or more)

3G (including 2.5G, sub3G)

4G

3G3G3G3G 3G (including 2.5G,

sub3G)4G

Major Requirement Driving Architecture 

Predominantly voice driven - data was always add on

Converged data and voice over IP

Network Architecture

Wide area cell-based Hybrid - Integration of Wireless LAN (WiFi,

Bluetooth) and wide area

Speeds 384 Kbps to 2 Mbps20 to 100 Mbps in mobile mode

Frequency BandDependent on country or continent (1800-2400 MHz)

Higher frequency bands (2-8 GHz)

Bandwidth 5-20 MHz 100 MHz (or more)

Switching Design Basis

Circuit and PacketAll digital with packetized voice

Access Technologies

W-CDMA, 1xRTT, EdgeOFDM and MC-CDMA (Multi Carrier CDMA)

3G3G3G3GSwitching Design Basis

Circuit and PacketAll digital with packetized voice

Access Technologies

W-CDMA, 1xRTT, EdgeOFDM and MC-CDMA (Multi Carrier CDMA)

Forward Error Correction

Convolutional rate 1/2, 1/3Concatenated coding scheme

Component Design

Optimized antenna design, multi-band adapters 

Smarter Antennas, software multiband and wideband radios

IP A number of air link protocols, including IP 5.0 

All IP (IP6.0)

3G3G3G3GIn reality, as of first half of 2002, 4G is a conceptual

framework for or a discussion point to address future needs

of a universal high speed wireless network that will interface

with wire line backbone network seamlessly.

4G is also represents the hope and ideas of a group of

researchers in Motorola, Qualcomm, Nokia, Ericsson, Sun,

HP, NTT DoCoMo and other infrastructure vendors who must

respond to the needs of MMS, multimedia and video

applications if 3G never materializes in its full glory.

3G3G3G3G4G standard 100Mbps (uplink) and 20Mbps (downlink),

allowing more bandwidth for new applications such as

video phones, video / audio download and interactive

games.

One of the two competitor networks to NTT DoCoMo, run

by KDDI/AU, has already upgraded to CDMA2000 1xEVDO

(an intermediate 3.25G technology that allows a data

transmission rate of up to 2.4Mbps).

3G3G3G3G4G AND THE FUTURE

It is suggested that 4G technologies will allow 3D virtual

reality and interactive video / hologram images. The technology

could also increase interaction between compatible technologies,

so that the smart card in the handset could automatically pay for

goods in passing a linked payment kiosk (i-mode can already boast

this capability) or will tell your car to warm up in the morning,

because your phone has noted you have left the house or have set

the alarm.

4G is expected to provide high resolution images (better quality

than TV images) and video-links (all of these will require a band

width of about 100MHz).

3G3G3G3G