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1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco Systems International

1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

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Page 1: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

1© 2004, Cisco Systems, Inc. All rights reserved.

Advances in License Exempt Wireless LANs

ITU-R Study Group 8 Seminar, September, 2004

Jan Kruys

Cisco Systems International

Page 2: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

2© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Introduction

• RLANs have become the reference for successful license exempt wireless

• It is important to understand how this got to be the case

• Other types of license exempt wireless systems are being proposed and developed

• How should regulation adapt to these challenges?

This material is contributed to interested fora for the purpose of assisting their discussions on the subject of spectrum regulations. The content reflects the personal views of the author; it does not in anyway reflect a Cisco Systems Corporate position nor does it commit Cisco Systems to support the conclusions presented .

Page 3: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

3© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Beginnings

• In the late 1980’s – the FCC opens up ISM bands for license exempt data communications

– on the condition that they use spread spectrum technology to avoid interference to each other

• frequency hopping, Direct sequence, limited maximum power/EIRP to 250mW/1W

• The computer industry recognizes the opportunity and a flurry of new designs appear

– and IEEE802.11 is formed to develop a standard

• The CEPT follows suit soon thereafter

– and ETSI develops certification criteria based on a low 100mW EIRP limit

Page 4: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

4© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Slow start

• The first devices were half the size of today’s notebook computers

– and almost prohibitively expensive

– but engineering got the size down quickly

• Marketing focused on wire replacement = cost saving

– slow overall adoption

– but some vertical markets developed quickly – like logistics

– few saw the benefit of wireless for the consumer

• But some saw the spectrum crunch coming and started the work on a 5GHz allocation “dedicated” to RLANs.

– that was 1994

Page 5: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

5© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

The transition

• During the mid 90’s the notebook computer comes of age and sales take off

• 1999: Apple Computer offers wireless for $100 per notebook

– for an 11 Mb/s card, integrated into the Apple notebooks

– all the PC vendors panic and prepare to offer it too

– the wireless industry scramble to meet the exploding demand

• And sales of wireless cards and APs sales exceed everyone’s expectations…..

– 10 years after the first devices were built

Page 6: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

6© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

RLANs today

HP iPAQ5450 PDAHP iPAQ5450 PDA

SharpM25X

Projector

SharpM25X

Projector

HP PrintersHP Printers

Cisco7920

Phone

Cisco7920

Phone

SiemensMedical SIMPad

SiemensMedical SIMPad

IntermecBarcodeScanner

IntermecBarcodeScanner

IBM Thinkpad PCIBM Thinkpad PC

Page 7: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

7© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Rolling on…

• 2003: sales of notebooks exceed sales of desktops– most of them have wireless integrated

• the main driver is increased worker productivity

• An RLAN module now costs less than $15 to build

• “Wi-Fi hotspots” have become the hottest new access medium

– that is offered by established and new “mobile” operators

• WRC-03 allocates 455 MHz in the 5GHz range to the Mobile Service for use by “Wireless Access Systems, including RLANs”

– after tough negotiations with the military about sharing the band

• IEEE802.11 starts development of a high speed version:– > 100 Mb/s, MIMO technology

Page 8: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

8© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Significant others

• Bluetooth

– complete solution for personal area network

– assumes to be the only spectrum occupant

– only the 1 mW version has made any impact

– still implements the “circuit” paradigm

• HomeRF

– another “complete solution”

– based on last year’s technology – frequency hopping

– still implements the “circuit” paradigm

• WiMAX and proprietary outdoor access solutions

– optimized PHY/MAC technology for access to IP based services

– cover fixed, nomadic and mobile use

– notably WiMAX promises to be “everything to all”

Page 9: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

9© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

WiMAX

• Operation from “0”-11 GHz

• OFDM/QAM• TDD/FDD

Page 10: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

10© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Grass roots versus the big bang

• The take-off of RLANs is due to three factors:

– it served the market with the strongest internal standards: computing

– it offered a pluggable replacement for fixed ethernet

– it was affordable at level of the individual

• The continued success of RLANs is due to its spectrum sharing design

– based on the “listen before talk” principle

• Other systems require large scale upfront investment of money and resources

– corporate business models are not conducive to bringing new, disruptive technologies to market

Page 11: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

11© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Two factors driving wireless access

• Wireless is perceived as a major enabler of economic growth

– and gets a lot of attention at government level

• The “IP paradigm” is spreading to the edge of the network – including the wireless edge

– it scales from very small to very large networks

– it is very efficient for computer to computer communications

– it is reasonably efficient for streaming trafficalready a lot of voice backhaul is carried over IP core networks at high efficiency

– Wireless has to be(come) IP capable• see the success of RLANs

• 3G is still circuit switched

Page 12: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

12© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

The spectral challenge

• There is never enough spectrum

– but the demand for operating range drops• facilitates spectrum re-use

– and smart technology helps to facilitate co-operation

• Sharing of spectrum will be the rule

– Vertical sharing – with incumbents• recognize and leverage specifics through embedded intelligence

– see RLANs and DFS: “recognition of repetition”

– Horizontal sharing – among newcomers• avoid/prohibit stomping on others

• share available spectrum gracefully under load

Page 13: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

13© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

A complex issue

Interference requires overlap in at least one dimension

Broadcasting

Coding/Information Bandwidth/Frequency

Duty Cycle/TimeSpace/Power

RF ID,RADAR

WLAN

UMTS

UW

B

Page 14: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

14© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Potential solutions

• Cognitive Radio Techniques– incumbent interference avoidance/prevention

– using different means like detection, geo-location database, pilot signals

• Footprint reduction– high gain antennas reduce chances of interference

• into incumbents as well as peers

• provides significant advantage of spectrum re-use

• Leveraging IP– IP based protocols are adaptive to load and resource variations

• accommodates intermittent link errors

• facilitates spectrum sharing with other users/systems

• while non-deterministic QoS supports voice and video

Page 15: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

15© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Footprint reduction

Relative Performance

-20.0

-10.0

0.0

10.0

20.0

30.0

360 - 60 - 20 - 10 - 5 - 2 - 1 degrees (Base station and Client aperture)

10lo

g (r

efer

ence

pa

cket

loss

/pre

dict

ed

pack

et lo

ss)

Single beam

6 beam (BS)

Page 16: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

16© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Leverage IP

Streaming video over a 5GHz RLAN link – flexibility to accept interference or other interruptions

Page 17: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

17© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

A new regulations paradigm?

• Assume that intelligent sharing is possible

– based on detection and/or active avoidance

• Match characteristics of incumbent with constraints on the newcomers

– avoid overlap of sharing dimensions (see UWB)

– define interference avoidance criteria

• statically – e.g. by location data base

• dynamically – e.g. DFS, beam switching or spread spectrum modulation

• Determine interference load budget for incumbents and leave it to industry to make best use of that budget

• Assume that technology and systems behaviour changes with time

– consider time limited, success-based renewal of sharing “permissions”

Page 18: 1 © 2004, Cisco Systems, Inc. All rights reserved. Advances in License Exempt Wireless LANs ITU-R Study Group 8 Seminar, September, 2004 Jan Kruys Cisco

18© 2004, Cisco Systems, Inc. All rights reserved.

JKR04-Genesis of RLANs

Thank you for your attention