Basic course on WiMAX Iparte roma3A - Comlab course on... · Marina Settembre - WiMAX basic course Ericsson Internal 10 2006-02-01 WiMAX Why the hype? OFDMA – ”Best Radio Interface

Basic course on WiMAX

Marina SettembreEricsson Lab iTaly

Marina Settembre - WiMAX basic course Ericsson Internal 2006-02-012

Agenda

Introduction – What is WiMAX? – Why WiMAX? – WiMAX in the broadband landscape

WiMAX architecture scenario and applicationsWiMAX standardsWiMAX spectrumWiMAX featuresWiMAX value chain and market aspectsConclusions


What is WiMAX?

www.wimaxforum.org

WiMAX– Worldwide Interoperability for Microwave Access

(it has become synonymous of IEEE 802.16)

Non profit industry trade organization formed to promote and certify compatibility and interoperability of broadband wireless products

– IEEE 802.16, ETSI HiperMAN wireless MAN standards

IEEE 802.16 is a standard for Broadband Wireless Access– Initially for fixed and nomadic applications (IEEE 802.16a or IEEE802.16

revd or 16-2004), but now also including limited mobility ( IEEE802.16e)

Majority of products found below 11 GHz– Licensed and unlicensed bands (2.5, 3.5 and 5.8 GHz)


WiMAX membersAt present there are ~ 300 member companies in the WiMAX forum, ~30% are operatorsSome of the important members are listed below:

• Airspan networks• Alcatel• Alvarion• Andrew Corporation• Aperto Networks• Atheros comm.• AT&T• BT• China Motion Telecom• Compliance certification services• Engim• Ensemble Comm.• Ericsson• Filtronics• Fujitsu

• France Telecom • Intel• L3 Primewave• LCC• Motorola• MTI• Navini Networks• News IQ• NextWave Telecom Inc• Nokia• OFDM Forum• Powerwave Technologies• Proxim• Raytheon RF components• Redline comm.

• RF integration• RF Magic• Siemens• SiWave• SiWorks• SR Telecom• Stratex Networks• Telenor • TowerStream• The Telnecity Group• TurboConcept• Wavesat Wireless• WiLAN• WaveSat• ZTE corporation• ... www.wimaxforum.org

Ericsson has been active as a principal member of the WiMAX forum since 2004


Why WiMAX?

Low cost high performance solution to deliver broadband wireless.

– One standard– Licensed and license exempt spectrum– Evolution to fixed to mobile

Business opportunity by reaching developed, developing and rural market. Complementing other access technologies


Wireless landscape


Wireless networks will coexist


The Hype cycle


Gartner Hype cycle (2004)


WiMAX Why the hype?

OFDMA – ”Best Radio Interface for urban env.”

Ethernet – “Has killed everything in its way, including ATM”

(Future) terminals perceived as inexpensive – Low complexity, no “IPR-tax”, global standard Huge volumes.

Follow wow for WiFi success story (IEEE 802.11)

Aggressive marketing (WiMAX Forum, Intel and others)


Gartner Hype Cycle 2005


Wimax deployment scenarios


• Extension for < 11 GHz• Targeted for non line of sight, Point-to-

Multi-Point applications -> “last mile”broadband access

802.16a(Jan 2003)

802.16(Dec 2001)

• Original air Interface for 10 – 66 GHz• Line-of-sight only, Point-to-Point applications

• 802.16 Revision PAR for 802.16 & 802.16a to address Errata

• Base for first WiMAX products

• Amendment for portability and mobility in licensed bands from 2-6 GHz

• Roaming for portable devices (laptops) within & between service areas

802.16e(2005 exp.)

802.16REV d(June 2004)

802.16 Standards Genealogy


Performance and features comparison

– All Claims Come with AssumptionsData Rates @ 64QAMCell Range @ 2.5 GHz, BPSK

– All Assumptions Must Be Tested

Mobile RangesIndoor Install with 802.16-2004

802.16-2004 802.16eJune 2004 Pending

(formerly 802.16d) (est. Q4 2005)Subscribers Fixed / Portable Fixed / Portable / Mobile

Channel ConditionsS-OFDMA (128-2000)

DuplexingSub-Carrier Modulation

Channel Bandwidth75 Mbps @ 20 MHz

15 - 18 Mbps @ 5 MHz20+ km: rural 3 km: indoor

2 to 5 km: suburban, urban 5 km: outdoor

IEEE Approval

LOS, Near-LOS, Non-LOS

OFDM-256ModulationTDD / FDD

BPSK, QPSK, 16QAM, 64QAMScalable: 1.25 MHz - 20 MHz

Cell Range

Data Rate (Peak) 15 Mbps @ 5 MHz


The global spectrum perspective on WiMAX

Spectrum in most every marketNot Always HarmonizedBands In Contention

– 3.5 GHz in US– 2.5 GHz in Europe– 5 GHz in Europe

North America:2.5, 3.5, 5 GHz

South America:2.5, 3.5, 5 GHz

Africa / Middle East:3.5, 5 GHz

Europe / Russia:3.5, 5 GHz

Asia Pacific:2.5, 3.5, 5 GHz


Spectrum 802.16 is Spectrum Agnostic but WiMAX defines ”Profiles”

Both licenced and unlicenced spectrum – but 802.16e in licensed only!


Unlicensed spectrumUnlicensed spectrum: 2.4 GHz and 5.8 GHzAdvantages:

– Fast roll out – Lower costs

Disadvantages:– Interference: other RF systems can also operate in the same spectrum– Increased competition: another operator could easily enter the market – Limited power: government regulations– Availability : the 5.8 GHz spectrum is not currently available in a number of

countries

Given these disadvantages, operators will carefully evaluate thepotential useof unlicensed spectrum, in particular at 2.4 GHz, before rolling out a networkExceptions: rural and remote regions where there is less likelihood of interference and competitions


Licensed spectrumLicensed spectrum: 700MHz, 2.3 GHz, 2.5 GHz, 3.5 GHzAdvantages:

– The licensed spectrum provides exclusive use of the spectrum– Better QoS

Disadvantages:– 2.5 GHz: at the moment is not in use in Europe and this band is also

designated for 3G– 3.5 GHz: It is currently available for use in virtually every country but

US, radio frequency propagation challenges inherent to this band, licenses restrictions on the spectrum usage ( limiting handoffs)

– 700 MHz: At this time there is no profile, but some interest in using this band( currently is being used by analog TV broadcasters)

– 2.3 GHz: usage in adjacent channels limits the amount of available bandwidth

WiMAX forum is currently petitioning regulators to change actualpolicy


WiMAX PHY FeaturesFeatures

Air interface: Single Carrier, OFDM , OFDMA

Adaptive modulation and variable error correction encoding for RF burst

TDD and FDD duplexing support

Flexible channel sizes (1.75 MHz,3.5 MHz,5MHz, 7MHz, 10MHz, 14MHz, 20MHz)

Designed to support smart antenna systems

BenefitsOFDM suitable for NLOS operation due to the simplicity of equalization

Ensures a robust RF link while maximising the bits/s for each users

Addresses varying worldwide regulations

Provides the flexibility to operate in different frequency bands with different channel requirements

Smart antennas are fast becoming affordable and able to mitigate interference and increase system gain


WiMAX MAC FeaturesFeatures

Packet base protocol

Scalable from one to hundreds of subscriber

Connection oriented

QoS Support:UGS, rtPS, nrtPS, BE

Adaptive modulation support

BenefitsFragmentation and PHS enabled forefficient IP traffic support

Cost effective deployments to deliver a robust business case

Automatic retransmission request (ARQ)

Security and encryption (tryple DES)

Automatic power control

Per connections QoS and fasterpacket routing

Higher data rates allowed for channel conditions, higher capacity

Hiding RF Layer induced errors from upper layer protocols

Protects user privacy

Enables cellular deployments by minimising self interference

Low latency, data prioritisation


WiMAX performance

WiMAX performance depends on many variables:– Deployment type: LoS vs near-LoS vs Non LoS– Terrain: rural vs sub-urban vs urban– Network type: spot vs continuous radio network– Radio Characteristics: frequency, channel bandwidth,

modulation and coding etc.

Too many variables to make simple tables of Bandwidth vs Coverage


LoS vs NLoS

Line of Sight•Directional user antennas•Mounted on roof-top•Fixed only•“50 km and 70 Mbit/s”

Non Line of Sight•Antennas inside laptop• End user self installation• Fixed or limited mobility•Coverage & capacity like 3G Evolved


Spot vs continuous radio cell


WiMAX and adaptive coding and modulationAdaptive Coding and Modulation: most suited burst profile (predefined coding and modulation scheme) dynamically selected according to radio link conditions


Examples of coverage

30m 30m

30m 30m

30 km 5.85 km

1.35 km 0.95 km

Downlink ~ 3Mbps Downlink ~ 4.8Mbps

Downlink ~ 7.2MbpsDownlink ~ 7.3Mbps


WiMAX PerformanceEstimate for 64QAM (3,5GHz/7MHz/10W)

0

5

10

15

20

25

0,1 1 10 100radius [km]

Mb/

s

0,9

1,7

3,1

20,0

Spot coverage, Single cell, Suburban, Roof topContinuous coverage, Multi-cell, Urban, Laptop/Indoor


WiMAX and other technologies


WiMAX value chain


Product availability


Conclusions: WiMAX…

– Won’t deliver 70Mbps in a 50 km mile cell NLOS– Won’t have cheaper fixed modem than cable or DSL

but it will..– Will provide 10Mbps in a 3km dense urban cell or about a 10 km rural cell– Will enable indoor self-install in licensed bands and/or very low frequency versions– Will be a DSL complement, supporting nomadic laptop mobility and VoIP telephony

and complement services provided by 3G technologies, complement WLAN – Will serve as an alternative backhaul for Wi-Fi hotspots – Will complement existing microwave solutions especially for low capacity point-to-

point applications such as in rural areas– Will provide ethernet based BWA, with different level of mobility

What Needs To Go Right:– 802.16e Ratification and Profile Creation– Continued Access To Spectrum & Movement Into New Bands– Services &Plannings– Devices and chips

What Could Go Wrong:– 802.16e Delays– Economics and market


Basic course on WiMAX Iparte roma3A - Comlab course on... · Marina Settembre - WiMAX basic course Ericsson Internal 10 2006-02-01 WiMAX Why the hype? OFDMA – ”Best Radio Interface

Documents