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SPECTRUM MANAGEMENT INCOGNITIVE RADIO NETWORKS
I. F. AKYILDIZI. F. AKYILDIZ
Broadband Wireless Networking LaboratoryBroadband Wireless Networking Laboratory
School of Electrical and Computer EngineeringSchool of Electrical and Computer Engineering
Georgia Institute of TechnologyGeorgia Institute of TechnologyTel: 404Tel: 404--894894--5141; Fax: 4045141; Fax: 404--894894--78837883
Email: [email protected]: [email protected]
Web: http://www.ece.gatech.edu/research/labs/bwnWeb: http://www.ece.gatech.edu/research/labs/bwn
IFA2008 AVIGNON 2
I.F. Akyildiz, W. Y. Lee, M.C. Vuran and S. Mohanty,I.F. Akyildiz, W. Y. Lee, M.C. Vuran and S. Mohanty,NeXt Generation/Dynamic Spectrum Access/Cognitive RadioNeXt Generation/Dynamic Spectrum Access/Cognitive RadioWireless Networks: A Survey,Wireless Networks: A Survey,Computer Networks (Elsevier) Journal,Computer Networks (Elsevier) Journal, Sept. 2006.Sept. 2006.
I. F. Akyildiz, W.Y. Lee, M. C. Vuran, and S. Mohanty,I. F. Akyildiz, W.Y. Lee, M. C. Vuran, and S. Mohanty,"A Survey on Spectrum Management in Cognitive Radio Networks,"A Survey on Spectrum Management in Cognitive Radio Networks,
IEEE Communications Magazine, April 2008.IEEE Communications Magazine, April 2008.
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IFA2008 AVIGNON 3
FIXED SPECTRUM ASSIGNMENT
IFA2008 AVIGNON 4
Fixed Spectrum UtilizationFixed Spectrum Utilization
Maximum Amplitudes
Amplitude(dBm)
Heavy Use Heavy Use
Medium UseSparse Use
Frequency (MHz)
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IFA2008 AVIGNON
Fixed Spectrum UtilizationFixed Spectrum Utilization
GHz
PSD (Power Spectrum Density)
Freq (GHz)Freq (GHz) 0~10~1 1~21~2 2~32~3
Utilization(%)Utilization(%) 54.454.4 35.135.1 7.67.6
3~43~4 4~54~5 5~65~6
0.250.25 0.1280.128 4.64.6
Measurements show that there is wide range of spectrum utilizationsacross 6 GHz of spectrum
IFA2008 AVIGNON 6
COGNITIVE RADIO NETWORKS;DYNAMIC SPECTRUM ALLOCATION NETWORKS (DSANs);
xG INITIATIVE
Dynamic SpectrumDynamic SpectrumAllocationAllocation
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IFA2008 AVIGNON 7
A Cognitive Radio is the key enabling technologyfor Dynamic Spectrum Access!!
Capability to use or share the spectrum in anopportunistic manner -> SPECTRUM HARVESTING
Dynamic spectrum access techniques allow theCR to operate in the best available channel
COGNITIVE RADIO
IFA2008 AVIGNON 8
Ultimate Objective of Cognitive RadioUltimate Objective of Cognitive Radio
CR enables the usage of temporally unused spectrumCR enables the usage of temporally unused spectrum Spectrum HoleSpectrum Holeoror White SpaceWhite Space..
If this band will be used by aIf this band will be used by a licensed userlicensed user,,CR moves to another spectrum holeCR moves to another spectrum hole
Alters itsAlters its transmission power level or modulationtransmission power level or modulation
scheme to avoid interferencescheme to avoid interference
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IFA2008 AVIGNON 9
Spectrum Hole ConceptSpectrum Hole Concept
Time
Frequency
Spectrum HolesPower
Spectrum Occupied byLicensed Users
IFA2008 AVIGNON 10
Senses RF Environment and modifies frequency,power or modulation
Dynamic Spectrum Selection Adaptive Modulation Adaptive Power Control Real Time Spectrum Management Significantly Increases Spectrum Efficiency
FEATURES OF COGNITIVE RADIO
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IFA2008 AVIGNON 13
A Cognitive Radio is a radio that canchange its transmitter parameters based oninteraction with the environment in which itoperates. (Federal Com Commission2005)
FCC (Non-Federal Use of the Spectrum)
WHAT IS A COGNITIVE RADIO?
IFA2008 AVIGNON 1414
Microsoft, Google, Dell, HPMicrosoft, Google, Dell, HPKNOWS: Kognitiv Networking Over White SpacesKNOWS: Kognitiv Networking Over White Spaces
http://research.microsoft.com/netres/projects/KNOWS/
Prototypes designed to identify wireless microphone, NTSCPrototypes designed to identify wireless microphone, NTSCand Digital TV signalsand Digital TV signals
Undergoing testing at FCCUndergoing testing at FCC
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IFA2008 AVIGNON 1515
AdaptrumAdaptrums Testbeds Testbedhttp://www.adaptrum.com/home
Experiments undertaken inExperiments undertaken inthe region of 500 MHzthe region of 500 MHz --700 MHz700 MHz
Undergoing testing at FCCUndergoing testing at FCC
IFA2008 AVIGNON 1616
Georgia Tech: OCRA TestbedGeorgia Tech: OCRA Testbedhttp://www.ece.gatech.edu/research/labs/mag/cognitive_radio.htm
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IFA2008 AVIGNON
Physical Architecture of the Cognitive RadioPhysical Architecture of the Cognitive Radio
(Cognitive Radio Transceiver)(Cognitive Radio Transceiver)
Receiver
Transmit
Touser
Fro
mu
ser
RF Front-End (Tx/Rx)
Control Parametrization (SDR)(Reconfiguration)
RadioFrequency
(RF)
Analog-to-DigitalConvertion
(A/D)
BasebandProcessing
DataProcessing
Modem Processor
IFA2008 AVIGNON
Physical Architecture of the Cognitive RadioPhysical Architecture of the Cognitive Radio(Wideband RF/Analog FRONT(Wideband RF/Analog FRONT--END Architecture)END Architecture)
Wideband Antenna
Analog-to-DigitalConverter
AGC A/D
VCO
PLL
RF Filter
Mixer
Voltage Controlled
Oscillator
ChannelSelection Filter
Low Noise
Amplifier
AutomaticGain Control
LNA
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IFA2008 AVIGNON
Cognitive Radio Network ArchitectureCognitive Radio Network Architecture
Primary
Base-station
Primary
User
Primary Network
Licensed Band I
Unlicensed Band
Licensed Band IICR Network
Access
PrimaryNetworkAccess
CRUser
Spectrum Band
CRBase-station
Cognitive Radio Network
(With Infrastructure)
OtherCognitive
RadioNetworks
Spectrum Broker
IFA2008 AVIGNON 20
CR Ad Hoc Networks ArchitectureCR Ad Hoc Networks Architecture
Primary
Base-station
Primary
User
Primary Network
Licensed Band I
Unlicensed Band
Licensed Band II
Cognitive Radio Network
(Without Infrastructure)
CR
Ad Hoc
Access
CRUser
Spectrum Band
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IFA2008 AVIGNON 2121
Cognitive Radio Network ArchitectureCognitive Radio Network Architecture
Primary
Base-station
Primary
User
Primary Network
Licensed Band I
Unlicensed Band
Licensed Band II
CR Network
Access
Primary
Network
Access
Cognitive Radio Network
(Without Infrastructure)
CR
Ad Hoc
Access
CRUser
Spectrum Band
CRBase-station
Cognitive Radio Network
(With Infrastructure)
OtherCognitive
RadioNetworks
Spectrum Broker
IFA2008 AVIGNON 22
Primary NetworkPrimary Network
An existing network infrastructure which hasAn existing network infrastructure which hasanan accessaccess right to a certainright to a certain spectrum band.spectrum band.
e.g., Common cellular systems ande.g., Common cellular systems andTV broadcast networks.TV broadcast networks.
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IFA2008 AVIGNON 23
Primary UserPrimary User(or Licensed User)(or Licensed User)HasHas a license to operate in a certain spectrum band.a license to operate in a certain spectrum band.
REMARK:REMARK:
Primary users do not need any modification or additionalPrimary users do not need any modification or additional
functions for cofunctions for co--existence with CR usersexistence with CR users
IFA2008 AVIGNON 24
(or Dynamic Spectrum Access Network,(or Dynamic Spectrum Access Network,
or Secondary Network or Unlicensed Network)or Secondary Network or Unlicensed Network)
* Does not have license to operate in a desired band.* Does not have license to operate in a desired band.
* Hence, the spectrum access is allowed only in an* Hence, the spectrum access is allowed only in an
opportunistic manner !opportunistic manner !
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IFA2008 AVIGNON 25
(or Unlicensed User, Secondary User)(or Unlicensed User, Secondary User)
has no spectrum licensehas no spectrum license
Hence, additional functionalities are requiredHence, additional functionalities are required
to share the licensed spectrum band !to share the licensed spectrum band !
IFA2008 AVIGNON 26
1) Determine which portions of the spectrum is available and detect thepresence of licensed users when a user operates in a licensed band
(Spectrum Sensing)
2) Select the best available channel (Spectrum Decision)
3) Coordinate access to this channel with other users (Spectrum Sharing)
4) Vacate the channel when a licensed user is detected(Spectrum Mobility Spectrum Handoff)
SPECTRUM MANAGEMENT FRAMEWORK
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IFA2008 AVIGNON 27
COGNITIVE CYCLECOGNITIVE CYCLE
Spectrum
Sharing
SpectrumDecision
SpectrumSensing
ChannelCapacity
Primary UserDetection
RFStimuli
SpectrumHole
Radio Environment
SpectrumMobility
DecisionRequest
TransmittedSignal
Spectrum (Channel)Characterization
IFA2008 AVIGNON 28
What is Spectrum Sensing ?What is Spectrum Sensing ?
How to detect spectrum holes
by the COGNITIVE RADIO so thatit can adapt itself to its environment !!
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IFA2008 AVIGNON 29
Classification of SpectrumClassification of Spectrum
Sensing TechniquesSensing Techniques
InterferenceTemperatureManagement
TransmitterDetection
Spectrum Sensing
ReceiverDetection
Matched FilterDetection
EnergyDetection
CyclostationaryFeature Detection
IFA2008 AVIGNON 30
Limitations of the TransmitterLimitations of the Transmitter DetectionDetection
Hidden Terminal Problem due toShadowing
Interference due to uncertainty ofreceiver location
CRTransmitter
Range
Primary Base-station
CR User
PrimaryTransmitter
Range
Primary User
Primary Base-station
PrimaryTransmitter
Range
Primary User
CRTransmitter
RangeInterference
Interference
CR User
Cannotdetect thetransmitter
Cannotdetect thetransmitter
Shadowing ProblemShadowing ProblemReceiver Uncertainty ProblemReceiver Uncertainty Problem
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IFA2008 AVIGNON 31
Transmitter DetectionTransmitter DetectionNonNon--Cooperative vs Cooperative DetectionCooperative vs Cooperative Detection
TransmitterDetection
Matched FilterDetection
EnergyDetection
CyclostationaryFeature
Detection
TransmitterDetection
Non-Cooperative
DetectionCooperativeDetection
Detection Method Detection Behavior
IFA2008 AVIGNON 32
Cooperative DetectionCooperative Detection
PrimaryUser
PrimaryBase-station
Multi-path fading
Weak signals arereceived due to themulti-path fading may not detectthe primary user
Shadowing
Cannot detectthe primaryuser due to theobstacles
Detect theprimary usercorrectly
By exchanging theirsensing information, CRusers can detect theprimary user underfading and shadowingenvironments
CR User 2
CR User 3
CR User 1
BUSY
IDLE
IDLE
BUSYBUSY
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IFA2008 AVIGNON 33
Primary Receiver DetectionPrimary Receiver Detection
InterferenceTemperatureManagement
TransmitterDetection
Spectrum Sensing
ReceiverDetection
Matched FilterDetection
EnergyDetection
CyclostationaryFeature Detection
IFA2008 AVIGNON 34
Primary Receiver DetectionPrimary Receiver Detection
PrimaryBase-station
Primary User
CR User
Local Oscillator (LO)Leakage Power
CR users detect theLO leakage power forthe detection ofprimary users insteadof the transmittedsignals
When primary usersreceive the signals fromthe transmitter, theyemit the LO leakagepower.
B. Wild and K. Ramchandran, Detecting Primary Receivers for Cognitive Radio
Applications in Proc. IEEE DySPAN, pp. 124130, Nov. 2005.
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IFA2008 AVIGNON 35
InterferenceInterference TemperatureTemperature
ManagementManagement
InterferenceTemperature
Management
TransmitterDetection
Spectrum Sensing
ReceiverDetection
Matched FilterDetection
EnergyDetection
CyclostationaryFeature Detection
IFA2008 AVIGNON 36
Interference Temperature ModelInterference Temperature Model
Powerat
Receiver
Original Noise Floor
InterferenceTemperature Limit
Licensed Signal
NewOpportunitiesfor Spectrum
Access
Minimum ServiceRange with
Interference Cap
Service Range atOriginal Noise Floor
Distance from Licensed Transmitting Antenna
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IFA2008 AVIGNON
Open Research for Spectrum Sensing
Sensing Parameter Optimization
(Based on Transmitter / Energy Detection )
WW..YY.. LeeLee and I. F.and I. F. AkyildizAkyildiz,, Optimal Spectrum SensingOptimal Spectrum Sensing
Framework for Cognitive Radio NetworksFramework for Cognitive Radio Networks,,
IEEE Trans. on Wireless Communications, Oct. 2008IEEE Trans. on Wireless Communications, Oct. 2008..
IFA2008 AVIGNON
Open Research for Spectrum Sensing
Optimization of Cooperative Sensing:
Determine the # of cooperating users and spectrum bands
Cooperative Feature (Cyclostationary) Detection Scheme:
For faster detection time and less complexity
Hybrid Transmitter & Receiver Detection:
Based on the activities both in uplink and downlink channels
RAT (Radio Access Technology)-Adaptive Spectrum Sensing:
Consider radio access technologies (TDMA, CDMA, FDMA, etc ) of primarynetworks
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IFA2008 AVIGNON 39
Spectrum DecisionSpectrum Decision
Spectrum
Sharing
SpectrumDecision
SpectrumSensing
ChannelCapacity
Primary UserDetection
RFStimuli
SpectrumHole
Radio Environment
SpectrumMobility
DecisionRequest
TransmittedSignal
Spectrum (Channel)Characterization
IFA2008 AVIGNON 40
SpectrumSpectrum DecisionDecision
Stage 1Spectrum Characterization
RF information Interference Path Loss Wireless LinkError
Link layerdelay
Primary NetworkInformation Primary UserActivity
Holding Time
Stage 2Decision
SingleSpectrumDecision
Multi-SpectrumDecision
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IFA2008 AVIGNON 41
SINGLE SPECTRUM DECISIONSINGLE SPECTRUM DECISION
CR user B
Occupied by primary users
CR user A
Idle spectrum band
Frequency(Hz)
Each CR user selects only one spectrum band according to theapplication requirements
SpectrumHandoff
CR user A
CR user B
IFA2008 AVIGNON 42
MultiMulti--Spectrum DecisionSpectrum Decision
Sub-channelsfor CR user B
Occupied by primary users
Sub-channelsfor CR user A
Idle spectrum band
Frequency(Hz)
CR users select multiple non-contiguous spectrum bands and use themsimultaneously for the transmission.
SpectrumHandoff
CR user A
CR user B
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IFA2008 AVIGNON
Open Research for Spectrum Decision
Spectrum Decision and Admission Control
for Real-time / Best Effort Applications
WW..YY.. LeeLee and I. F.and I. F. AkyildizAkyildiz,,
QoSQoS Aware Spectrum Decision for Cognitive Radio NetworksAware Spectrum Decision for Cognitive Radio Networks,,
Submitted for publicationSubmitted for publication, July 008, July 008..
IFA2008 AVIGNON
Open Research for Spectrum Decision
Primary Network Modeling and Analysis
Primary User Behavior Predictivity Models
CR Channel Characterization / Estimation:
In terms of QoS parameters (throughput, PER, delay, jitter,etc)
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IFA2008 AVIGNON
Open Research for Spectrum Decision
Spectrum Decision with Reconfiguration:
Determine not only spectrum bands (operating frequency,
bandwidth) but also transmission parameters
(transmission power, modulation, channel coding,
upper layer protocols, etc)
IFA2008 AVIGNON 46
Spectrum SharingSpectrum Sharing
SpectrumDecision
SpectrumSensing
ChannelCapacity
Primary User
Detection
RFStimuli
SpectrumHole
Radio Environment
SpectrumMobility
DecisionRequestSpectrum
Sharing
TransmittedSignal
Spectrum(Channel)Characterization
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IFA2008 AVIGNON 47
Spectrum SharingSpectrum SharingSpectrum SharingSpectrum Sharing ssimilar to MAC Problemsimilar to MAC Problems
Multiple CRMultiple CR userusers try to access the spectrums try to access the spectrum
Access must be coordinated (to prevent collisions inAccess must be coordinated (to prevent collisions in
overlapping portions of the spectrum)overlapping portions of the spectrum)
UniquenessUniqueness
Coexistence with licensed (primary) usersCoexistence with licensed (primary) users
WWide range of available spectrumide range of available spectrum
IFA2008 AVIGNON 48
SPECTRUM SHARINGSPECTRUM SHARINGCLASSIFICATIONCLASSIFICATION
IntraIntra--Network SSNetwork SS InterInter--Network SSNetwork SS
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IFA2008 AVIGNON 49
IntraIntra--Network Spectrum SharingNetwork Spectrum Sharing
Centralized Spectrum Sharing
IFA2008 AVIGNON 50
IntraIntra--Network Spectrum SharingNetwork Spectrum Sharing
Distributed Spectrum Sharing(Cooperative)
Sending local observationsSending spectrum allocations
Spectrum sharing entity
Distributed Spectrum Sharing(Non-Cooperative)
Spectrum sharing entity
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IFA2008 AVIGNON 51
InterInter--Network Spectrum SharingNetwork Spectrum Sharing
Distributed Spectrum SharingCentralized Spectrum Sharing
Sending Local ObservationsSending Spectrum Allocations
Spectrum Sharing Entity
CR Network A
CR Network B
CR Network C
Spectrum Broker(or Spectrum Server)
CR Network A
CR Network B
CR Network C
IFA2008 AVIGNON 52
Why Game Theory?Why Game Theory?
[Spectrum Sharing in CR networks][Spectrum Sharing in CR networks] CR users have a common interest to have theCR users have a common interest to have thespectrum resources as much as possible.spectrum resources as much as possible.
However, CR users have competing interests toHowever, CR users have competing interests tomaximize their own share of the spectrummaximize their own share of the spectrumresources.resources. i.e., the activity of one CR user cani.e., the activity of one CR user canimpact the activities of the othersimpact the activities of the others
Also CR userAlso CR users rational decisions require anticipatings rational decisions require anticipatingrivalsrivals responsesresponses
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IFA2008 AVIGNON 53
Why Game Theory?Why Game Theory?
Provides anProvides an efficient distributed spectrum sharingefficient distributed spectrum sharingscheme.scheme.
Provides theProvides the wellwell--defined equilibrium criteriadefined equilibrium criteria for thefor thespectrum sharing problemspectrum sharing problem to measure the optimalityto measure the optimality ininvarious network scenarios.various network scenarios.
IFA2008 AVIGNON
Intranetwork Spectrum Sharing
Repeated SpectrumSharing Game Model(R. Etkin, A. Parekh, and D. Tse,IEEE DySPAN 2005)
Local Bargaining(Cao/Zheng,IEEE SECON 2005)
Auction BasedSpectrum Sharing Game(J. Huang, R. Berry, and M. L. Honig,ACM Monet Journal, 2006)
Belief Assisted
Pricing(J. Zhu and Ray Liu
IEEE Com. Magazine, May 2007).
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IFA2008 AVIGNON
Internetwork Spectrum Sharing
O, Ileri, D. Samardzija,and N. MandayamIEEE DySPAN 2007
M. Bennis andJ. LillebergProc. CISS 2007
S. Gandhi, C. Buragohai
L. Cao, H. Zheng, S. SIEEE DySPAN 2007
X. Jing, D. RaychaudhuriIEEE DySPAN 2005
IFA2008 AVIGNON
Open Research for Spectrum Sharing
Inter-Cell Spectrum Sharing based on JointSpectrum and Power Allocation
W. Y. Lee and I.F.W. Y. Lee and I.F. AkyildizAkyildiz,,
``Joint Spectrum and Power Allocation for Inter``Joint Spectrum and Power Allocation for Inter--Cell SpectrumCell Spectrum
Sharing in Cognitive Radio Networks,'Sharing in Cognitive Radio Networks,'
in Proc. IEEEin Proc. IEEE DySPANDySPAN2008, Chicago, IL, USA, October2008, Chicago, IL, USA, October2008.2008.
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IFA2008 AVIGNON
Open Research for Spectrum Sharing
Inter-User (Intra-Cell) Spectrum Sharing:
RAT adaptive-CR MAC Protocol / User power control
Inter-Network Spectrum Sharing:
Spectrum Auctions among CR operators
IFA2008 AVIGNON 58
Spectrum MobilitySpectrum Mobility
SpectrumDecision
SpectrumSensing
ChannelCapacity
TransmittedSignal
Primary User
Detection
RFStimuli
SpectrumHole
Radio Environment
SpectrumSharing
DecisionRequest
SpectrumMobility
Spectrum(Channel)Characterization
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IFA2008 AVIGNON 59
Spectrum MobilitySpectrum Mobility/Handoff/Handoff Get the Best Available ChannelGet the Best Available Channelconceptconcept
CR radioCR radio cancan capture the best availablecapture the best available channelchannel
SpectrumSpectrum MMobilityobility//HandoffHandoff (a(a new type of handoffnew type of handoff)) isisdefined as the process when a CR userdefined as the process when a CR user (SU)(SU) changes itschanges its
frequency of operationfrequency of operation
When channel conditions become worse or a primary userWhen channel conditions become worse or a primary user(PU)(PU) appearsappears, spectrum handoff happens, spectrum handoff happens
IFA2008 AVIGNON 60
Spectrum HandoffSpectrum Handoff ExampleExample
Time
Frequency
Spectrum HolePower
Spectrum occupiedby Licensed users
Spectrum HandoffSpectrum Handoff
Sensing issue
Spectrum handoff is amulti-step process,it includes:
Primary User Detection(Sensing issue)
Channel Switching(Hardware issue)
Resume Communication(Sharing issue)
Sharing issue
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IFA2008 AVIGNON
MORE RESEARCH CHALLENGESCOMMON CONTROL CHANNEL PROBLEM- ClusteringClustering
-- Predefined in licensed bandPredefined in licensed band
-- Reserved in licensed band as Coordinated Access Band (CAB)Reserved in licensed band as Coordinated Access Band (CAB)
-- Located at the lower edge of unlicensed band withLocated at the lower edge of unlicensed band with
CommonCommon Spectrum Coordination Channel (Spectrum Coordination Channel (CSCC) ProtocolCSCC) Protocol
IFA2008 AVIGNON
MORE RESEARCH CHALLENGES
Wideband RF front-end:
Support Fast sensing/switching /reconfiguration
Admission Control Framework:
Cooperate with spectrum decision, spectrum mobilityand inter-cell spectrum sharing
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IFA2008 AVIGNON
MORE RESEARCH CHALLENGES CR QoS Framework:
Enable QoS guaranteeing communications for various service classes:conversational, streaming, interactive, and background.
Primary User Activity Modeling / Estimation:
Based on the RAT of primary networks
CR Transmission Scheme with Error Control:
Adaptive to primary user activity as well as channel condition
IFA2008 AVIGNON
MORE RESEARCH CHALLENGES
CR Security:
Jamming, PU emulating attack, etc.
PHY-Adaptive Spectrum Management Framework
(Sensing / Decision / Sharing /Mobility):
OFDM, MIMO, Directional Antenna, UWB, etc.
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IFA2008 AVIGNON
MORE RESEARCH CHALLENGES
CR Deployment Scenarios:
New network architecture or applications based on
CR technology, Cooperation model between PU and SUs
CR Network Management:
O&M (Operation and Maintenance), Billing
IFA2008 AVIGNON 68
Proposal for aCR Network Management Framework
System
Monitoring
QoS Management
BillingDecision/ Policy
Management
SecurityManagement
SLAManagement(Inter/Intra)
ServiceAdaptation
Intra-operatorMobility Manager
Inter-operatorMobility ManagerReconfiguration
Intra-operatorResource Manager
Inter-operatorResource Manager
Mobility ManagementSpectrum Management
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IFA2008 AVIGNON 69
CognitiveCognitive Radio NetworkRadio Network StandardsStandards
IEEE 802.22 (IEEE 802.22 (Wireless Regional Area Networks)Wireless Regional Area Networks)(Cognitive Radio for TV Bands/Channels) (2004)(Cognitive Radio for TV Bands/Channels) (2004)
IEEE P1900 (2005)IEEE P1900 (2005)
IFA2008 AVIGNON 70
What is a NanoWhat is a Nano--Network?Network?I.F. Akyildiz, F. Brunetti, C. Blazquez,I.F. Akyildiz, F. Brunetti, C. Blazquez,
Nanonetworking: A New Communication ParadigmNanonetworking: A New Communication ParadigmComputer Networks, Elsevier, Sept. 2008Computer Networks, Elsevier, Sept. 2008..
Interconnection of Multiple Devices at NanoInterconnection of Multiple Devices at Nano--scalescale
Communication Point of View:Communication Point of View:
NanoNano--scale communication includingscale communication including
transmitter and receiver devices,transmitter and receiver devices,
information, carrier and medium.information, carrier and medium.
Examples:Examples:
Molecular CommunicationMolecular Communication
Architectural Point of View:Architectural Point of View:
Electronic integration at nanoElectronic integration at nano--scalescale
Examples:Examples:
Carbon nanotubes and networksCarbon nanotubes and networks--onon--
chip (NoC)chip (NoC)
Two Research BranchesTwo Research Branches
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IFA2008 AVIGNON 71
NanoNano--Machine DevelopmentMachine Development
IFA2008 AVIGNON 72
NanoNano--machine Development: Topmachine Development: Top--Down ApproachDown Approach
Development of nano-scale objects by downscaling current existing micro-
scale device components.
Fabrication and assembly processes are at an early stage
Only simple mechanical structures can be created
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IFA2008 AVIGNON 73
NanoNano--machine Development: Bottommachine Development: Bottom--up Approachup Approach
Nanomachines are developed using individual molecules as building
blocks.
Molecular manufacturing technologies able to assemble nano-
machines molecule by molecule do not exist.
IFA2008 AVIGNON 74
NanoNano--machine Development: Biomachine Development: Bio--hybrid Approachybrid Approac
Biological nano-machines found in nature are used as models to
develop new nano-machines.
They can also be used as building blocks integrating them into
more complex nano-machines.
Several biological structures found in living organisms can
be considered as nano-machines.
They can be found in biological systems where they are
interconnected to perform more complex tasks.
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IFA2008 AVIGNON 75
Communication Mechanisms forCommunication Mechanisms for NanoNetworksNanoNetworks??
CommunicationCommunication
techniquestechniques
ElectromagneticElectromagnetic
WavesWaves
AcousticAcoustic
CommunicationCommunication
NanoNano--mechanicalmechanicalCommunicationCommunication
MolecularMolecular
CommunicationCommunication
Electromagnetic communication could be used to transmitElectromagnetic communication could be used to transmit
information from a microinformation from a micro--device to adevice to a nanonano--machine, but notmachine, but not
amongamong nanonano--machinesmachines
With the current technology, acoustic communication cannotWith the current technology, acoustic communication cannot
be used in nanonetworksbe used in nanonetworks
Nanomechanical communication is currently not a solutionNanomechanical communication is currently not a solution
for nanonetworksfor nanonetworks
Molecular communication can be used to interconnectMolecular communication can be used to interconnect
nanonano--machines, resulting inmachines, resulting in nanonetworksnanonetworks!!
IFA2008 AVIGNON 76
A Possible Solution:A Possible Solution: Molecular CommunicationMolecular Communication
Molecular communication is defined as the transmission andMolecular communication is defined as the transmission and
reception of information encoded in moleculesreception of information encoded in molecules
It is a completely new andIt is a completely new and
interdisciplinary field thatinterdisciplinary field that
spans nano, bio andspans nano, bio and
information technologiesinformation technologies
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IFA2008 AVIGNON 77
NanoNetworksNanoNetworks vsvs Traditional Communication NetworksTraditional Communication Networks
FeaturesFeatures TraditionalTraditional MolecularMolecular
Carrier:Carrier: Electromagnetic wavesElectromagnetic waves MoleculesMolecules
Signal type:Signal type: Electronic, optical,Electronic, optical,mechanicalmechanical
ChemicalChemical
Propagation speed:Propagation speed: Sound or lightSound or light Extremely lowExtremely low
Medium conditions:Medium conditions: Wired: almost immuneWired: almost immune
Wireless: affectWireless: affectcommunicationcommunication
Affect communicationAffect communication
Noise:Noise: Electromagnetic field andElectromagnetic field andsignalssignals
Particles and molecules inParticles and molecules inmediummedium
Other features:Other features: High energy consumptionHigh energy consumption Low energy consumptionLow energy consumption
IFA2008 AVIGNON 78
NanonetworksNanonetworks ComponentsComponents
MolecularMolecular
communicationcommunication
TraditionalTraditional
communicationcommunication
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IFA2008 AVIGNON 79
ShortShort--Range CommunicationRange Communication
Two possibleTwo possible
communicationcommunication
systemssystems
Molecular MotorsMolecular Motors
CalciumCalcium IonsIons
IFA2008 AVIGNON 80
LongLong--Range Communication using PheromonesRange Communication using Pheromones
Features:Features:
CommunicationCommunication
RangeRange
MediumMedium
CarrierCarrier
mmmm -- kmkm
PheromonesPheromones
Wet and dryWet and dry
-
8/12/2019 CognitiveRadio KEY
41/41
IFA2008 AVIGNON 81
Research Challenges inResearch Challenges in NanonetworksNanonetworks
11..
Development ofDevelopment of
nanonano--machines,machines,
testbedstestbeds andand
simulation toolssimulation tools
2.2.
TheoreticalTheoretical
3.3.
Architectures andArchitectures and
ProtocolsProtocols