8/8/2019 Cognitive Radio From Utopia to Reality by P.pawelczak
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1
Faculty of Electrical Engineering, Mathematics and Computer Science
Delft University of Technology
Cognitive Radio:From Utopia to Reality
Freeband Ambient Communication Event, Enschede
Przemysaw Paweczak
July 4, 2006
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Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
Network structure
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
Network structure
Functional mapping
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
Network structure
Functional mapping
Proposed protocols
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
Network structure
Functional mapping
Proposed protocols Channel access
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July 4, 2006 2
Faculty of Electrical Engineering, Mathematics and Computer Science
Background
History: why cognitive radio? (Mitolas definition, spectrum utilization)
New concepts in spectrum regulation (pooling, DSA, OSA, auctioning, licensing...)
Standardization (P1900, 802.22), Conferences
AAF project: Dynamic Spectrum Access for emergency networks
Network structure
Functional mapping
Proposed protocols Channel access
Directions for the future
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Faculty of Electrical Engineering, Mathematics and Computer Science
Cognitive Radio: Some History
The point in which wireless personal digital assistants and the related networks
are sufficiently computationally intelligent about radio resources and related
computer-to-computer communications to detect user communications needs
as a function of use context, and to provide radio resources and wire less servicesmost appropriate to those needs
Joseph Mitola III, Cognitive Radio: An Integrated Agent Architecture for Software
Defined Radio, PhD dissertation, Royal Institute of Technology (KTH) Stockholm,
Sweden, 8 May, 2000
Cognitive radio is a paradigm for wireless communication in which either
network or wireless node itself changes particular transmission or reception
parameters to execute its tasks efficiently. This parameter alteration is based on
observations of several factors from external and internal cognitive radio
environment, such as radio frequency spectrum, user behavior, and network state
http://en.wikipedia.org/wiki/Cognitive_radio.
http://en.wikipedia.org/wiki/Cognitive_radiohttp://en.wikipedia.org/wiki/Cognitive_radio8/8/2019 Cognitive Radio From Utopia to Reality by P.pawelczak
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Faculty of Electrical Engineering, Mathematics and Computer Science
Some History
Spectrum in 400-1000 MHz range (courtesy: Ir. Marnix Heksamp, measurement: AT)
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
Spectrum Leasing: lease of spectrum by regulator
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
Spectrum Leasing: lease of spectrum by regulator
Spectrum Sharing: giving a chunk of spectrum to set of parties
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
Spectrum Leasing: lease of spectrum by regulator
Spectrum Sharing: giving a chunk of spectrum to set of parties
Negotiated Spectrum Use: who can exploit spectrum at particular moment better,
gets it
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
Spectrum Leasing: lease of spectrum by regulator
Spectrum Sharing: giving a chunk of spectrum to set of parties
Negotiated Spectrum Use: who can exploit spectrum at particular moment better,
gets it
Regulator independent management
Opportunistic Spectrum Use: use of primary users spectrum such that no
additional interference is introduced
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Faculty of Electrical Engineering, Mathematics and Computer Science
New concepts: Spectrum Management
Regulator dependent management
Spectrum Pooling: two or more parties decide how to pool the resurces given by
regulator
Spectrum Leasing: lease of spectrum by regulator
Spectrum Sharing: giving a chunk of spectrum to set of parties
Negotiated Spectrum Use: who can exploit spectrum at particular moment better,
gets it
Regulator independent management
Opportunistic Spectrum Use: use of primary users spectrum such that no
additional interference is introduced
Dynamic Spectrum Access: access to licensed channels based on policies ergo itclosely mimics operation of Cognitive Radio
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
P1900.2: Recommended Practice for Interference and Coexistence Analysis
(intention to participate by TU Delft)
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
P1900.2: Recommended Practice for Interference and Coexistence Analysis
(intention to participate by TU Delft)
P1900.3: Recommended Practice for Conformance Evaluation of SoftwareDefined Radio (SDR) Software Modules
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
P1900.2: Recommended Practice for Interference and Coexistence Analysis
(intention to participate by TU Delft)
P1900.3: Recommended Practice for Conformance Evaluation of SoftwareDefined Radio (SDR) Software Modules
IEEE 802.22: Standard for a cognitive radio-based PHY/MAC/air interface for use
by license-exempt devices on a non-interfering basis in spectrum allocated to the
TV Broadcast Service (draft by end 2006?)
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
P1900.2: Recommended Practice for Interference and Coexistence Analysis
(intention to participate by TU Delft)
P1900.3: Recommended Practice for Conformance Evaluation of SoftwareDefined Radio (SDR) Software Modules
IEEE 802.22: Standard for a cognitive radio-based PHY/MAC/air interface for use
by license-exempt devices on a non-interfering basis in spectrum allocated to the
TV Broadcast Service (draft by end 2006?)
FCC: Rules to Permit Unlicensed National Information Infrastructure (U-NII)
devices in the 5 GHz band (comments from TU Delft)
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Faculty of Electrical Engineering, Mathematics and Computer Science
Standardization, Conferences
P1900.X: IEEE Standard Series on Next Generation Radio and Spectrum
Management
P1900.1: Standard Terms, Definitions and Concepts for Spectrum
Management, Policy Defined Radio, Adaptive Radio and Software DefinedRadio (TU Delft involved in work)
P1900.2: Recommended Practice for Interference and Coexistence Analysis
(intention to participate by TU Delft)
P1900.3: Recommended Practice for Conformance Evaluation of SoftwareDefined Radio (SDR) Software Modules
IEEE 802.22: Standard for a cognitive radio-based PHY/MAC/air interface for use
by license-exempt devices on a non-interfering basis in spectrum allocated to the
TV Broadcast Service (draft by end 2006?)
FCC: Rules to Permit Unlicensed National Information Infrastructure (U-NII)
devices in the 5 GHz band (comments from TU Delft)
IEEE DySPAN, IEEE Crowncom
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Faculty of Electrical Engineering, Mathematics and Computer Science
Advances in Cognitive Radio: AAF Project
During disaster in Enschede, the Netherlands, in May 2000, where a fireworks
depot exploded and destroyed a large part of the city, killing 23 people and injuring
more than a thousand. Fire brigade, police and relief workers of the medical team
experienced a great deal of communication breakdown, both internally and witheach another.
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Faculty of Electrical Engineering, Mathematics and Computer Science
Advances in Cognitive Radio: AAF Project
During disaster in Enschede, the Netherlands, in May 2000, where a fireworks
depot exploded and destroyed a large part of the city, killing 23 people and injuring
more than a thousand. Fire brigade, police and relief workers of the medical team
experienced a great deal of communication breakdown, both internally and witheach another.
The two main factors that caused difficulty in coordinating the teams
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Faculty of Electrical Engineering, Mathematics and Computer Science
Advances in Cognitive Radio: AAF Project
During disaster in Enschede, the Netherlands, in May 2000, where a fireworks
depot exploded and destroyed a large part of the city, killing 23 people and injuring
more than a thousand. Fire brigade, police and relief workers of the medical team
experienced a great deal of communication breakdown, both internally and witheach another.
The two main factors that caused difficulty in coordinating the teams
Lack of common standards for each disaster relief group
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Faculty of Electrical Engineering, Mathematics and Computer Science
Advances in Cognitive Radio: AAF Project
During disaster in Enschede, the Netherlands, in May 2000, where a fireworks
depot exploded and destroyed a large part of the city, killing 23 people and injuring
more than a thousand. Fire brigade, police and relief workers of the medical team
experienced a great deal of communication breakdown, both internally and with
each another.
The two main factors that caused difficulty in coordinating the teams
Lack of common standards for each disaster relief group
Overloaded emergency frequency bands
8/8/2019 Cognitive Radio From Utopia to Reality by P.pawelczak
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Faculty of Electrical Engineering, Mathematics and Computer Science
Advances in Cognitive Radio: AAF Project
During disaster in Enschede, the Netherlands, in May 2000, where a fireworks
depot exploded and destroyed a large part of the city, killing 23 people and injuring
more than a thousand. Fire brigade, police and relief workers of the medical team
experienced a great deal of communication breakdown, both internally and with
each another.
The two main factors that caused difficulty in coordinating the teams
Lack of common standards for each disaster relief group
Overloaded emergency frequency bands In spite of Netherlands having a common radio communication platform for all
emergency services based on TETRA above observation is striking reminder that
one can do better
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Faculty of Electrical Engineering, Mathematics and Computer Science
AAF Architecture: Network
...
IAN Manager (vehical node,eg. incident command post)
IAN to IAN link
CH to Node link
IAN
Key list IAN Manager (IM) andController (SRM) of allIAN sensing domains
LU device
JAN
EAN
Wired link
IAN
IAN
IAN member and sesingnode (personal node, eg.
first responder)
P. Paweczak, et al. , Dynamic Spectrum Access: An Emergency Network Case Study,
submitted to IEEE Wireless Comm. Mag., 1 July 2006
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AAF Architecture: Node
GSM
UMTS
TETRA
GPS
SDR Platform
AAF
UHF
Emergency
Other
Analog
Frontend
A/D
D/ABaseband Processing RX/TX
Analog
FrontendA/D
data bits
Power / Feature
Measurement
Local
Decision
Global
Decision
FOI
TX/RX
Spectral Analysis System Decision System
FOI: Frequency Occupancy Information
SRM: Spectral Resource Manager
FSS: Frequency Scanning System
BB CTL: Baseband control
Dig. Ch. Sel.: Digital Channel Selection
TX: Transmitter
RXReceiver
Policies
SRM
FOI
Coordination
BB CTL
FSS
Dig. Ch.
Sel..
Channel Selection
Higher protocol Layers
P. Paweczak, et al. , Dynamic Spectrum Access: An Emergency Network Case Study,
submitted to IEEE Wireless Comm. Mag., 1 July 2006
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Spectrum Scanning: A Major Problem
Shadowing: where an individual sensing node may be
blocked by an obstacle, therefore may not be able to
see the Primary User (PU)
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Spectrum Scanning: A Major Problem
Shadowing: where an individual sensing node may be
blocked by an obstacle, therefore may not be able to
see the Primary User (PU) Multipath fading: where the signals from the PU that
travel different paths may or may not add coherently at
the receiver. As a result, small changes in location
relative to the wavelength of PU impact the Quality of
Detection.
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Spectrum Scanning: A Major Problem
Shadowing: where an individual sensing node may be
blocked by an obstacle, therefore may not be able to
see the Primary User (PU) Multipath fading: where the signals from the PU that
travel different paths may or may not add coherently at
the receiver. As a result, small changes in location
relative to the wavelength of PU impact the Quality of
Detection.
Solution: Cooperative Scanning
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Spectrum Scanning: Theoretical Result
0 20 40 60 80 1000
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
N
Z(N)
tis/tc=0
tis/tc=0.001
tis
/tc
=0.005
tis/tc=0.01
P. Paweczak et al., Performance Measures of Dynamic Spectrum Access Networks,
accepted for publication on IEEE Globecom 2006
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Spectrum Scanning: A Proposed Solution
FOIdataNode1FOIdataNode2
FOIdataNodek
Node IAN Manager
Sensing
FOIdataNode1FOIdataNode2
FOIdataNodek
IAN 1
IAN C
CP
IAN 1 broadcast
CMP
IAN C broadcast
IAN 1 broadcast
IAN C broadcast
P. Paweczak et al., Cluster-Based Spectrum Sensing Architecture for Opportunistic
Spectrum Access Networks, submitted to IEEE Milcom 2006
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Spectrum Scanning: A Proposed Solution
Sensing
phaseIAN 1 IAN C CP
FOI data:
Node1
Nodes to IAN transmission
Data communication
phase
Guard
bandIAN 1 IAN C IAN 1 IAN C
IAN manager to IAN managerbroadcast IAN manager to nodes broadcast
Sensing data frame from IAN nodes
ID FEC
CMP
Combined
data: Nodes1-k
m
ID FEC NJL SNLCAL FECIDFOI data:
Node km
ID FEC
Communiation on CCCCommunication on
LU channels
CAL: Channel Availability ListCP: Contention PhaseCH: Cluster HeadCMP: Cluster Management PhaseFEC: Forward Error CorrectionFOI: Frequency Occupancy InformationNLJ: Newly Joined ListSNL: Scheduled Nodes List
P. Paweczak et al., Cluster-Based Spectrum Sensing Architecture for Opportunistic
Spectrum Access Networks, submitted to IEEE Milcom 2006
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Spectrum Scanning: some performance results
Plots of probability of scheduling measurement to node non existent in the cluster,
NC=250, R=500, tcp=1 ms, tsl=0.5 ms, v=0.5 m/s.
0 10 20 30 40 500
0.05
0.1
0.15
0.2
0.25
0.3
0.35
P
s
ticf
km=15
km=10
km=5
P. Paweczak et al., Cluster-Based Spectrum Sensing Architecture for Opportunistic
Spectrum Access Networks, submitted to IEEE Milcom 2006
S S i AAF T b d ( U i i f T )
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Spectrum Scanning: AAF Testbed (courtesy: University of Twente)
Ch l A i t
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Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
Ch l A i t
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Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
According to our measurements PU activity can be modeled with exponential
distribution (memoryless property)
Channel Assignment
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Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
According to our measurements PU activity can be modeled with exponential
distribution (memoryless property) Different channel access schemes can be proposed
Channel Assignment
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Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
According to our measurements PU activity can be modeled with exponential
distribution (memoryless property) Different channel access schemes can be proposed
Network chooses a channel randomly Random (RnD)
Channel Assignment
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Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
According to our measurements PU activity can be modeled with exponential
distribution (memoryless property) Different channel access schemes can be proposed
Network chooses a channel randomly Random (RnD)
Least-used (LeU), when network chooses for new flow channel m with
min(1, . . . , M)
Channel Assignment
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Faculty of Electrical Engineering, Mathematics and Computer Science
Channel Assignment
Because of the PU activity DSA network has to know which channel to use for
communication first
According to our measurements PU activity can be modeled with exponential
distribution (memoryless property) Different channel access schemes can be proposed
Network chooses a channel randomly Random (RnD)
Least-used (LeU), when network chooses for new flow channel m with
min(1, . . . , M) Least-used with Channel Hopping (LeUCH), when network chooses a
channel according to LeU scheme finds out that PU wants to use the it then
tries to choose another channel with the smallest m possible and continue
transmitting rest of the data there.
Channel Assignment: Example of PU Activity
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Channel Assignment: Example of PU Activity
0 1000 2000 3000 4000 5000 6000 7000 80003
4
5
6
7
8
9
10
Measurement number
Signalv
alue
[dBV/m]
Channel Assignment: Simulation Analysis
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Channel Assignment: Simulation Analysis
0 2 4 6 8 100
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Load [Erl]
Blocking
probability
M=5 (RND)
M=10 (RND)
M=20 (RND)
M=5 (LU)
M=10 (LU)
M=20 (LU)M=5 (LUCH)
M=10 (LUCH)
M=20 (LUCH)
0 2 4 6 8 100
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Load [Erl]
Blocking
probability
P. Paweczak et al., Performance Measures of Dynamic Spectrum Access Networks,
accepted for publication on IEEE Globecom 2006
Conclusions
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Conclusions
Cognitive Radio is a very fresh research topic
Conclusions
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Conclusions
Cognitive Radio is a very fresh research topic
AAF is probably the first European project strictly related to this issue
Conclusions
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Conclusions
Cognitive Radio is a very fresh research topic
AAF is probably the first European project strictly related to this issue
Research community needs to cooperate with policy regulators
Conclusions
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Faculty of Electrical Engineering, Mathematics and Computer Science
Cognitive Radio is a very fresh research topic
AAF is probably the first European project strictly related to this issue
Research community needs to cooperate with policy regulators
The core of any DSA system is spectrum scanning without physical wideband
scanning devices no implementation is possible
Conclusions
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Faculty of Electrical Engineering, Mathematics and Computer Science
Cognitive Radio is a very fresh research topic
AAF is probably the first European project strictly related to this issue
Research community needs to cooperate with policy regulators
The core of any DSA system is spectrum scanning without physical wideband
scanning devices no implementation is possible
Work on spectrum scanners is ongoing
Conclusions
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Faculty of Electrical Engineering, Mathematics and Computer Science
Cognitive Radio is a very fresh research topic
AAF is probably the first European project strictly related to this issue
Research community needs to cooperate with policy regulators
The core of any DSA system is spectrum scanning without physical wideband
scanning devices no implementation is possible
Work on spectrum scanners is ongoing
Proper mathematical models are needed for analysis of DSA systems
Contact Information
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Contact Information
Przemysaw Paweczak, PhD Student
Delft University of Technology
Wireless and Mobile Communications Group
Mekelweg 4, 2628 CD Delft, the Netherlands
Phone: +31 15 27 86697
Fax: +31 15 27 81774
Email: [email protected]
WWW: www.pawelczak.net
http://www.pawelczak.net/http://www.pawelczak.net/