Transcript The 2.4 GHz ISM band

The 2.4 GHz ISM band
Paul Hansell
CEng MIEE
Managing Director, Aegis Systems Ltd
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Structure of the presentation
 Background
 objectives & approach
 applications
 Study findings
 problem areas
 possible policy solutions
 Recommendations
 core recommendations
 further recommendations
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Study background
 2.4 GHz ISM band
 largely “licence exempt”
 regulation is minimal
 access is free
 global allocation
 ideally suited to high density fixed and mobile
… has led to increasing demand for use
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Study objectives
The objectives of the work were:
 to estimate demand for use of the band currently
and over the next two to five years
 to forecast bottle-necks for the use of new wireless
technology
 to advise on spectrum management strategies for
handling demand
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Study method
 Literature review
 Industry consultation
 50 people from 37 organisations contributed:
 20 face to face interviews (13 organisations)
 10 telephone interviews (9 organisations)
 20 written contributions
 Special thanks to the FEI
 Congestion modeling & analysis
 Recommendations
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Structure of the band
ISM
Military
2450
2445
2446
SRD
AVI
2455
2454
Outside Broadcast Links
Radio Local Area Networks (Rec 70-03)
Short Range Devices (Rec 70-03)
2400
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2410
2420
2430
2440
2450
2460
2470
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2.4 GHz - diverse applications
User type
Licence fee
paid
Military

Electronic News Gathering and Outside Broadcast

Public provision of Fixed Wireless Access

Wireless Networking:
Radio LANs
Bluetooth
SoHo and Home networking
Other short range devices: RF Identification Devices
Video applications
ISM applications:
Microwave ovens
Sulphur plasma lighting
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Diverse expectations of growth
User type
Growth
expectation
Static
Military
Electronic News Gathering and Outside Broadcast
Public provision of Fixed Wireless Access
Wireless Networking:
Radio LANs
Bluetooth
SoHo and Home networking
Other short range devices: RF Identification Devices
ISM applications:
Modest
High
Very High
High
High
Video applications
Low
Microwave ovens
Low
Sulphur plasma lighting
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Low
Low (nil?)
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Forecasting congestion
 Based on earlier Aegis & SE24 work
 Used appropriate working assumptions for
system parameters (eg power, duty cycle)
 Density figures based on market forecasts
 Sought to identify key areas of concern
 high: systems likely to experience on-going,
noticeable degradation in QoS
 moderate: occasional noticeable degradation
 low: no noticeable degradation
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Problems: potential congestion
Victim
Indoor
RLAN
Outdoor
RLAN
RFA
Home
RF
Bluetooth
RFIDs
ENG/OB
Interferer
Indoor RLAN
Outdoor RLAN
RFA
Home RF
Bluetooth
RFIDs
ENG/OBTV
… outdoor applications - the key problem area
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Problems: licence issues
 Today:
 Use of outdoor RLANs by ISPs
 Tomorrow:
 Use of any licence exempt application to compete
with a licensed service (ie UMTS / FWA)
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Policy options: containment
 Do nothing
 not good for “UK plc”
 Close the band
 no expansion of RFA
 prevent any further outdoor RLANs
 Tighten constraints

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directional antennas
polite operations
power limits
digital technology
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Policy options: migration
 Refarming

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
Military
ENG/OB
RFA
Wireless networking
 New licence exempt bands
 5 GHz ISM
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Core recommendations
1. Congestion
 Address congestion from outdoor applications by
refarming
 Ideally refarm two out of three applications:
 if not: mandate power control, directionality, digitalisation
2. Licensing
 Resolve ISP legitimacy question
 Note potential impact on UMTS/FWA vs customer choice
3. Hot spots
 Limit public services to 1mW
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Additional recommendations
 Military
 Discuss military vacation of band to reduce
uncertainty and help standardise licence situation
 Polite operations
 Should be actively encouraged
 Further licence exempt bands
 Explore possibilities for additional spectrum
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Conclusions
 2.4 GHz ISM offers great potential for UK
 Future congestion is manageable but
requires action now w.r.t. outdoor systems
 Action on licensing needed once public vs
private issue resolved
 Additional licence exempt bands merit
further thought
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Balfour House,
Churchfield Road,
Walton-on-Thames,
Surrey KT12 2TD
United Kingdom
Tel: +44 1932 237800
Fax: +44 1932 237801
web: www.aegis-systems.co.uk
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