Cognitive Radio

Cognitive RadioAn Integrated Agent Architecture for

Software Defined Radio

Dissertation Defense8 June 2000

J. Mitola III

2

Copyright Legend

This work is the intellectual property of Joseph Mitola III.The copyright is herewith asserted.

No part of this material may be duplicated, reproduced, copied, dowloaded, or stored electronically except for non-commercial

educational purposes.

The copyright owner is willing to provide copyright permissionfor purposes that are generally in the public interest as defined

by the laws of the United States and/or Sweden.Contact [email protected]

This legend applies to the Licentiate Thesis, to the Doctoral Dissertationto the Radio Knowledge Representation Language (RKRL) frames,

and to the source code of the CR1 rapid prototype.

3

Agenda

• Overview of Cognitive Radio• Mathematical Foundations• Cognitive Radio Rapid Prototype (CR1)• Questions

4

Motivation from the User’s Perspective

Cost /QoS?Who Pays?Urgency?

“It Depends”

©1995-99 Mitola’s STATISfaction used with permission for Educational Purposes Only

5

Motivation from the Radio Perspective

Antenna RF Modem

INFOSECBasebandUser Interface

Equalizer

RAM

...

Model-Based ReasoningCognition

Antenna RF Modem Baseband User Interface

Hardware

INFOSEC

Back End ControlBaseband Modem

EqualizerAlgorithm

Software

Software RadioSoftware Modules …..

G. Maguire and J. Mitola, “Cognitive Radio: Making PCS Personal”, IEEE PCS Magazine, August 99J. Mitola III, “Software Radio Architecture Evolution” IEICE Transactions on Communications, July 00

RKRL FramesRadio Knowledge RepresentationLanguage (RKRL)

Secure Downloads, Pro-Active Radio Resource Management

6

Cognitive Radio Overview

WidebandA/D-D/A*

Wideband RFConversion

ProgrammableProcessor(s)

Software Radio

J. Mitola: “Software Radio: Technology and Prognosis” Proc., IEEE National Telesystems Conference 1992“Software Radio Architecture” IEEE Communications Magazine, May 1995Cognitive Radio, Licentiate Thesis,KTH (Royal Institute of Technology), Stockholm

HF LVHF VHF-UHF Cellular Indoor & RF LAN VHDR

2 MHz 28 88 400 960 MHz 6 34 GHz1.39 GHz

PCS

2.5 5.9

Software Radios

Very Low Band Low Mid Band High Band

Cellular Mobile

Public Safety

Fixed Terrestrial

4 Channels

Antenna RF Modem

INFOSECBasebandUser Interface

Model-Based ReasoningRKRL Frames

Spatial &Temporal

Knowledge

7

Detect User Communications Context

StadiumAirport

Autobahn

City Center

Industrial

Shopping

Residential

Suburb

J. Mitola, Cognitive Radio, KTH Licentiate Thesis, Sep 99

Where? When? Compared to Observed Patterns?Topics of Conversation? => Natural Language ProcessingAdapts to the User => Machine Learning

… and Arrange Appropriate Wireless Access

8

A Priori Radio Knowledge

(Global control, Inference-Engine, Meta-level capabilities, Cognition cycle, Agent-to-agent communications (KQML, KIF, )

Universe, Self, Concepts, Time, Space, User,

Spatial: Global, Satcom, Regional, Metro, Local,

Radio Functions: Air Interface, Internal, Hardware, Software, Standards: SDL (Z.100), UML, ODP(X.900), MPI, References Internal: Modem, Demodulator, Equalizer, Memory, Protocol: Physical, Data Link, Network, Segmentation, Messages, Physical Models: Radio Propagation, User, Context

Meta-Level

A PrioriKnowledge

Current States

Taxonomy

RKRL 0.3 Contains 4,000 frames of XML (Available in Excel)

9

RKRL Overview

RKRL j

<Frame>

<Handle><Model><Body><Context><Resource-specification>

RKRL contains Meta, UniverseMeta contains …Universe contains ...

RKRL0

contains

<Root><Source><Time><Place>

<Resources><Depth><Breadth><Sub-Elements><Sub-Frames>

Micro-world j := {<Frame>}*

Extensible Markup Language (XML) www.w3.org

Syntax

Air Interface contains GSM

GSM RF > 860 MHz

The RF of GSM is at least 860 MHz

(Air Interface = GSM)&& ?RF => 860 MHz

Resource Models

Control of Software Radio Resources

Control of the Reasoning Process

10

Reasoning About One’s Own Internal Structure

Antenna RF Modem INFOSEC

MessageProcessing

& I/O

Air

Router

I

C

I

C

I

C

I

C

CC

V

D

FC

LAN

I/O I/O I/OI/O

RF IFor

BB

BitsCT

BitsPTAux Aux Aux Fill

C C C C C

Control and Common System Equipment

RemoteControl/Display

UserControl(MMI)

External Environment

SourceSet

Joint ControlChannel Coding & Decoding

ChannelSet

Multiple Personalities

Radio Node

EvolutionSupport

INFO-SEC

Service&

NetworkSupport

SourceCoding

&Decoding

ModemIF

Process-ing

RF/ChannelAccess

Software-DefinedRadio (SDR)

Forumwww.sdrforum.org

5 Technical Meetings / Yr

Mitola, J., “Software Radio Architecture: A Mathematical Perspective” IEEE Journal on Selected Areas of Communication, April, 1999

European,Asian,

US Participation

Raises Decideability Questions

Entity Reference Model, Middleware

11

Software Radio Properties

Real Time Stream

Near Real Time

On/Off-Line

Service Bandwidth, Ws

Channel Bandwidth Wc

Power

Frequency

Spectral Purity

EnvironmentCharacterization

AdvancedControl

Wideband A/D & D/A Spectrum Access

Channel Isolation

FFT

Upconvert

BitstreamProcessing

Demodulate

SNR/ BER OptimizationInterference SuppressionBand/Mode Selection

On Line Adaptation

Modulate

BitstreamProcessing

Larger Network

Transmit

WB Digital

Bitstream

Receive

IsochronismThroughputResponse Time

ServiceQuality

Wideband orMultiband RF

ADCs

ASICs,FPGAs,DSPs,

Processors

HardwarePlatforms

SoftwareFactory

Appendix A, IEICE Invited Paper on Software Radio Architecture

12

Approach Based on the Cognition Cycle

Observe

OrientEstablish Priority

Plan

Decide

ActOutsideWorld

Send a Message

Receive a Message

Set Display

Read Buttons Save Global States

Allocate Resources

Initiate Process(es)(Isochronism Is Key)

Generate Alternatives(Program Generation)

Evaluate AlternativesParse

Pre-process

Infer on Context Hierarchy

UrgentImmediate

Normal

Register to Current Time

PriorStates

NewStates

Learn

13

CR1 Research Prototype

14

Small Vocabulary Large

Continuous Words Isolated

Dependent Speaker Independent

Speech

Speech Recognition

Synthesis

Speech

Parse (Syntax) Extract StructureAnalyze Structure

Inte

rling

ua

Lexical MapperSyntax Generator

Estimate Statistics

Ontology (Domain Concepts)

Grammar, LexiconStructure ModelsFeature Models

TextPhoneme ExtractionModeling (e.g. HMM)Structure AnalysisTranscript Generation

Erro

rful

Tra

nscr

ipt

Speech Synthesizer

Text

ExtractInformation

Kno

wn

Clu

ster

sMachine Processing

Natural Language Processing

Machine-GeneratedStreams

15

Rep

rese

nta

tion

Spa

ce

Numeric

Symbolic

Learning StrategySupervised Unsupervised

ArtificialNeuralNetworksPowerful GeneralizationPerformance DegradesWhen IrrelevantFeatures are Present

ConceptualClusteringSet Cover UsingGeneralization &Specialization

Pro

duct

ion

Rul

esF

eatu

re V

ecto

rsP

redi

cate

Cal

culu

s

FeatureClusteringSet PropertyReinforcementEstimation overMeasurements,Documents

AbductiveInferenceOccam’s RazorOver StructuredFeature Spaces

Wor

d V

ecto

rs

N-G

ram

s GeneticAlgorithmsBlind Learning, RobustSlow, Massively ParallelConstrained by the Coding of Chromosomes

Case-BasedStorage of ExamplesMemory BasedNearest-NeighborInductive RetrievalAdapt Pre-StoredSolutions to CurrentSituation(Does not requirea-priori model of the solution space)

Knowledge-BasedStructure backgroundknowledge in Rule BaseAcquires New RulesMay Use Certainty Calculus

EntropyNetworkLogic TreeTransformedto Neural Net(N-0.5, 0.5)

HiddenMarkovModels

Concept-BasedAcquires NewPredicates

Machine Learning Approach

CLARION

16

Sleep

Dynamic KnowledgeH

iera

rch

y of

Rei

nfo

rced

Seq

uen

ces

Best Match

NeedSleep

KnownStimulus

NovelStimulus

Sequence Formation

StimulusCorrelation

Sensory Interface

Characters

Words

Phrases

Dialogs

Scenes

Response(s)

Sleep

srModelsStimulus

Response

Delta (e.g. Delay)

Reinforcement

Dynamic Knowledge is a mix of Declarative Knowledge, Cues (Links),and Procedural Knowledge

17

The Cognitive Radio Architecture

Sensory Data

Words

Phrases

Dialogs

Novel

Own User

Radio Knowledge

HomeNetwork

Other Networks

Other People

Other Places

Other Things

World, W

Sequ

ence

For

mat

ion

Map

s Nearest

Scenes

KnownScene

Bindings

DialogBindings

PhraseBindings

WordBindings

DialogStates

ActionRequests

Plans

Actions

World Model, S

PDA

18

Original Contributions• Characterized SDR Architecture (Appendix A)

• Developed Necessary Mathematical Foundations– Topological Model of Radio Architecture (Appendix B)

– Computability Proof for Bounded-Recursive Functions

• Defined RKRL with Set-Theoretic Axioms

• Invented the Cognition Cycle

• Simulated the Contributions of a Notional Cognitive Radio – Spectrum Rental, Demand Shaping

• Implemented a Research Prototype CR1– Simulated environment, not fully integrated, illustrative personalities

• Articulated an Open Architecture Framework

19

Implications of Spectrum Rental

Current ResearchAutonomous Evolution of Spectrum Rental ProtocolsWhite Paper for the US FCC Technical Advisory CommitteeRecommended DoD, APCO, ?, Experiment under FCC Lead

20

Towards Cognitive Radio

------- On

tology --------------------

Model Structure

Aware

Mod

el Refinem

ent

Cog

nitio

n T

asks

Pre-programmed None

Goal-driven User Service Objective RF Band Protocol

Context AwareEnvironment Aware

Location Aware Geography, City Map

Building Floor Plan, Temperature, Lighting

Natural Language, Societal Roles, Discourse

Internally Aware Radio Functions, Components, Design RulesNetwork Aware Signaling, Protocol Stacks

Model Scope

Capable of Planning

Computer Aware Computational Resources (Memory, Processing)

Temporal Calculus, Constraint LanguageNegotiations KQML-capable, Gaming, Uncertainty, Value

Learns Fluents

Adapts Plans

Adapts Protocols

Builds signal models (unsupervised)

Cause-and-Effect Over Space-Time-Uses

General Models of User, Content, RF, Networks-- F

ormalized K

nowledge -----------

Mod

els Mediate P

erforman

ce ----------

Model A

cquisition --------------------------------------

Competence

Knowledge-basedCompetent

Inquisitive-Expert

21

Enduring Contribution

Architecture

Functions Components Design Rules

Detect UserCommunicationsContext

User InterfaceNatural Language ProcessingMachine Learning Components

ArrangeAppropriateWireless Access

SDR Structure ControlProtocol MediationSelf-Referential ComponentsSpatial-Temporal Components

MapsMust PreserveTopologicalStructureFinitely

Enables the Integration of Inter-Disciplinary Contributions

22

Mathematical Foundations

23

Y(t)

Point Set Topology

A Set

oo

o

o

Y

o o

{o

o}

Y

Contains

{o}

{o}

OY

o}{o

{o

o}

OY

Closed UnderA Familyof Subsets

{o}{o}

{o}

{o}

OY

oo

o

o

Y(i)

1 2 3 4i

24

Mappings Among Signal Spaces

Y(t)

oo

o

o

Y(i)

1 2 3 4i

Open Ball

f: Subsampling: Y(t) Y(I)

Infinite Dimensional Space(Not Countable)(e.g. Hilbert Space)

FiniteDimensionalSpace(Countable)(e.g. Z)

25

Topology Preserving Mappings

Y(t)

oo

o

o

Y(i)

1 2 3 4i

Open Ball

f: Subsampling ADC: Y(t) Y(I)f-1: Shannon-Nyquist: Y(I) Y(t)

Homeomorphism f: 1 to 1, ONTO Inverse Images of Open Sets Are Open Sets“Topology Preserving”

26

Radio Domain

Hi Band RF

Low Band RF

IF ADCChannel Filter Modem

Vocoder

Interface Points

Functional Transformations

RF

UserVolume

Channel Selection

Control Transformations

Topological Analysis: What are the domain and range? Are they explicit?What are the open sets? What are the Unions, Intersections?

Hi Band Antenna

Low Band Antenna

IF ADC

IF Channel Filter

Demodu-late

Voice Coder

Modulate

Voice DecodingRF Up Conversion

Speaker

IF Waveform Clear Bits

Baseband Waveform

Analog Audio

Is each map a homeomorphism?Are the inverse images of open sets open?

27

Topology of Models of the World

GPS

PDA

User

Home

Work

Today

Yeseterday

Monday

GSM

GPRS

RF LAN

DatabaseEurope

X

Informal Knowledge:Insufficient Structure

TopologicalSpaces

Ox ContainsX,

Countable Unions and

FiniteIntersections

UserRFLAN: NoPDARFLAN: YesEuropeHome: No

EuropeWork: Sometimes?

SufficientStructure

Subsets of X

Time

Places

Radio

People

Sensor

GPS

PDA

User

Home

Work

Today

Yeseterday

Monday

GSM

GPRS

RF LAN

Europe Database

Software

X

28

RKRL Defines Knowledge Topology

GPS

PDA

User

Home

Work

Today

Yeseterday

Monday

GSM

GPRS

RF LAN

Europe Database

X

Model

Membersof

Subsets

Time

Places

Radio

People

Sensor

Software

Identify

Familiesof

Subsets

29

Computational Domain

ADC 2 Input StreamDirect Memory Access

Channel Filter

Phase Estimator

State Decision

Bit Decision

Timing Recovery Logic

Demodulator DSP Hardware Space

ADC 1 Input StreamDirect Memory Access

Use of DSP Hardware Indicated as Area

Advanced Timing Recovery Logic

Processor Unit (s)

ProgramI/O

RAMROM

time

ISA

x

x

xx

Isochronous(Real-time)Domain

Turing/RecursiveCapability

time

x

x

xx

partialIsochronous Window

t<

BoundedFor I < N < *C

C = MIPSConstrained

30

PDA Architecture Domain

S(t) WSets of Pointsin the

World, W

Amplitude

Time

PDA

Receive

World-Model,

S

Nyquist

Open Ball

Propagation

Model Error

G ( ) = Propagation ( Nyquist ( ) )

ADC

Amplitude

Time

** *

** *

*

x(i) S

H ( ) = ADC ( Receive ( ) )

31

World, W

PDA

Sets of Points

World-Model,

S

Space

Time

Frequency

Behavior as (Homeo?)morphism

5 ActSense

1 Observe

3 Plan

4 Decide

Error OpenBall

2 Orient

Predict

Describe

32

Architecture Mappings

Sensory Data

Words

Phrases

Dialogs

Novel

Own User

Radio Knowledge

HomeNetwork

Other Networks

Other People

Other Places

Other Things

World, W

Sequ

ence

For

mat

ion

Map

s Nearest

Scenes

KnownScene

Bindings

DialogBindings

PhraseBindings

WordBindings

DialogStates

ActionRequests

Plans

Actions

World Model, S

PDA

33

Experimental Aspect

CR-1

34

RF Bands and Modes GSM (IS-136, etc) GPRS (UWC-136 ...) 3G (W-CDMA …) RF LAN AM Broadcast FM Broadcast NOAA Weather Police, Fire, etc.

Environment SensorsLocation: GPS (Glonass, …) Accelerometer Magnetometer (North)Positioning: Environment Broadcast (Doors, Coke Machines, ...)Timing: Precision Clock GPS Clock UpdatesOther: Ambient Light Digital Image, Video Clip Temperature

Effectors Speech Synthesizer Text Display RF Band/ Mode Control

Local Sensors Speech Recognizer Speaker ID Keyboard, Buttons

Environment-aware PDA

J. Mitola., “Cognitive Radio for Mobile Multimedia Communications”, MoMuC 99 Nov 99J. Mitola III, “Software Radio” Remarks before the Federal Communications Commission Apr 99

©1995-99 Mitola’s STATISfaction used with permission for DoD Use Only

{PDA

35

Simulated PDA(s)

36

Simulation Control

37

PDANode srModel,srCount, srDelaynodeName, modelName

PDASensor observationcapability

PDAEffector currentEffect

capability

PDANodeCum enableSlot, trigger-,statewindow, parseWindow

PDANodeLinks linksModel,-Count, -Delay

state

PDANodeSequencer state

PDANodeTrigger state

PDANodeWord runNode( )

PDANodePhrase runNode( )

PDANodeNovelty enableSlot, state, capacity

PDANodeNullDet Array stimSlot

PDANodeOr Array stimSlot

PDANodeBuffer window

Cognitive Radio 1 (CR1)

Java Class Hierarchy

©1995-99 Joseph Mitola III and The MITRE Corporation used with permission for DoD Use Only

38

Atomic Stimuli

Atomic Symbols

Primitive Sequences

Basic Sequences

Sequence Clusters

Context Cluster

RKRL

Handle

Body

Model

-World

CR1 Term, Example

Words, token, image

Phrases, video clip, messages

Dialogs, Paragraphs, Protocol

Scenes in a play, Session

Phoneme, pixel

Observation Hierarchy


Reinforced Hierarchical Sequences

39

Proc0 Sensors, Sequencers, Triggers

Proc1 Character-level Processing Known/new Letters, Word Aggregation, Word Links

Proc2 Word-level Processing Known/new Words, Phrase Aggregation, Phrase Links

Proc3 Phrase-level Processing Known/new Phrases, Dialog Aggregation, Dialog Links

Proc4 Dialog-level Processing Known/new Dialogs, Scene Aggregation, Scene Links

Proc5 Scene-level Processing Known Scenes, New Scenes

Proc6 Orient Phase

Proc7 Plan Phase

Proc8 Decide Phase

Proc9 Act Phase Effectors

Environment

Ob

serv

e P

has

e

Context?Training?Done?Command?

Here? Now?What?

Conflicts?

AllocatedResources?

CR1 Rapid Prototype

Case MatchingBindingWarping


40

GPRS Sensor

GPRS Effector

3G Sensor

3G Effector

TextmessageBuffer

MessagesModel

E-MailSystem

E-MailSystem

CostModel

Observation

Mode ChoiceModel

Models

CommunicationsContext

Sending or Delaying E-mail

41

Understanding CR1’s Behavior

42

Modulator

3G Sensor

3G Effector

Observe

Protocol

Here, Now

RF/Channel

SNR/BER Model

3G ParametersModel

ModelsProtocol

Demod

User Context

SNR

BER

Constellation

Data Rate

Mode Control Models


43

Dialog1

Observe

Scenes

Dialogs

Phrases

Words

OrientIntro-

duction

PlanIntro-

duction

Firstname = chip

r.f.l.a.n, n.o.w, h.e.r.e,t.c.p, q.u.e.r.y, f.i.r.s.t.n.a.m.e=> r.f.l.a.n, n.o.w, h.e.r.e, t.c.p, r.e.s.p.o.n.s.e, l.a.s.t.n.a.m.e|

s.a.y, n.o.w, h.e.r.e, a.r.e, y.o.u, l.a.s.t.n.a.m.e.?

r.f.l.a.n, n.o.w, h.e.r.e,

q.u.e.r.y, c.h.i.p

Next-phrase pointer

Scenes and Dialogs

44

Conclusions

• Dissertation Sets Forth the Principles & Vision– Bounded Loops, Integrated RKRL Model of SDR

– The Cognition Cycle, Reinforced Hierarchical Sequences

– Case-based Machine Learning (ML)

• Interesting Future Research– Spectrum Rental and Related Policy

– Performance Aspects: Metrics, Test Cases

– Detect, Learn, Predict Rote Behavior of Users

– Simulate PDA-Network Interactions

45

Backup Slides

46

RKRL Overview

47

Formalization in Micro-worlds

Micro-worldTask Domain

Formal ModelComputable Semantics

InformalInferences

Plausible Event Streams

FormalInferences

Mathematically Viable

AxiomatizationMathematical Statements

LanguageOntology, Syntax

Knowledge BaseExpressions That Are Defined in the Domain

Inference EnginePattern MatchingPlan Generation

Describes

Models

True-InDefines Just

ify

Proves

Operates-On

Supports

FormalizeS

uppo

rts

Describes

Defines

Stated-In

48

Ontological Models(Global control, Inference-Engine, Meta-level capabilities, Cognition, Agent-to-agent communications (KQML, KIF, )

Universe, Self, Concepts, Time, Space, User,

Spatial: Global, Satcom, Regional, Metro, Local,

Radio Functions: Air Interface, Internal, Hardware, Software, Standards: SDL (Z.100), UML, ODP(X.900), MPI, Internal: Modem, Demodulator, Equalizer, Memory, Protocol: Physical, Data Link, Network, Segmentation, Messages, Naïve Physics: Radio Propagation,

References, )

Meta-Level

A PrioriKnowledge

Current States

Taxonomy

Goal: Incremental Formalization across Various Domains©1995-99 Joseph Mitola III used with permission for DoD Use Only

49

RKRL Overview

RKRL j

<Frame>



RKRL0

contains





Syntax


GSM RF > 860 MHz

The RF of GSM is at least 860 MHz

(Air Interface = GSM)&& ?RF => 860 MHz

Resource Models

Control of Software Radio Resources

Control of the Reasoning Process


50

Incremental Formalization


Meta-Level

Concepts

Stockholm

Time

Now

Date-Time

YearMonth

Day

Space

Person

PDA

Radio Knowledge

(partial)

Self

DSP Pool

Constellation

Modulator

Universe

Physical World

Global Plane

Regional Plane

Centrum

Metropolitan Plane

Iridium

Models…Space*Time*RF*Entity*

* Axiomatic Models

Ontological Models(Representation Sets)

Informal Models(Natural Language)

New RKRL Frames:DSP Pool Processors Type = C6xDSP Pool Processors Number = 4DSP Pool Processors MIPS = 2600

Alternate RKRL Frames:DSP Pool Contains ProcessorsProcessors Number 4Processors MIPS 2600

S p a c e

F r e q u e n c y

T i m e

51

RKRL Interpretations


RKRL j

<Frame>



RKRL0

contains




Syntax


GSM RF > 860 MHzThe RF of GSM is at least 860 MHzAir Interface = GSM & RF? => 860 MHz

srModel: Stimulus -> Response

Propositional CalculusEntity-Attribute-Value AnalysisVector AttributesNeural NetworksGenetic Structures (partial GA)

IF (Model, Handle, Context) THEN (Body)

Rule-based Expert SystemsForward ChainingPredicate CalculusLimited Theorem Proving

CASE: Model(Handle, Body, Context)

Case-based ReasoningNearest-Neighbor RetrievalDecision-tree RetrievalData Base AnalysisConceptual Clustering

Interpretations


52

Spectrum Rentals

53

A Spectrum Pool Etiquette

HF LVHF VHF-UHF Cellular Indoor & RF LAN VHDR

2 MHz 28 88 400 960 MHz 6 34 GHz1.39 GHz

PCS

2.5 5.9

Software Radios

Very Low Band Low Mid Band High Band

Cellular Mobile

Public Safety

Fixed Terrestrial

54

Pooled Spectrum Rental

Offeror

10 msPeak Power

time

10 ms

Advertise

Express Interest

Time, Locale, Price (TLC)

TLC Bid, Authenticate

Accept/Reject Bid,Authenticate

Tender and Flag

RenterUse… No Objections

MonitorRelease

8 ms

(Dissertation Plan: Use RKRL and a Genetic Algorithm to AutonomouslyDerive the Details of this Protocol and to Use It in A Simulated Environment)

55

Pooled Spectrum Backoff Protocol

Legacy

20 ms

timeTransmit

Renter

Listen

5 ms

20 ms 20 ms

5 ms

ConflictRecognize

Defer (Report)

Transmit

Listen

Transmit

Listen

Transmit

56

Cognitive Radios Can Obey Rental Constraints

• Renters should not interfere with legacy users– Self-regulated power: location and propagation/ interference models

– Renters must limit their power to those specified in the rental posting• Take advantage of shadowing and 1/R4… losses• Accurate prediction = dynamic siting• Renting radio must tell user of constraints (don’t go up the hill)

• Renters Must Obey Use Precedence1. Emergencies - Established by authorities, inferred from events

2. Government - Attributed by band, channel modulation, coding, KQML

3. Public Interest - Default by band, KQML, inferred from events

4. Commerce - Default by band and mode, inferred (messages, actions)

5. Other - Recreational, sports, hobbies, etc. inferred

• Renters must create dynamic network & gateways– Protocol choice should be content/context-driven

– Protocol evolution

57

Modeling the Propagation Context

Handle: SASBody: RV at door tw CSContext: Stockholm/…Model: "/stockholm/Sunday 980516a/RVATDO~1.JPG

The Dynamic Model Frame Is Continuously Updated. Processing Yields Fine-scale Local Context (“Near Curb”)Storage At Critical Events Provides Memory

LCC, RF CAD, WrAP, ...

59

Morning RushS

TC

Fra

cti

on

s

Spatial RegionsAirport Autobahn CityCenter Industrial Shopping Residential Suburb Stadium

0

0.2

0.4

Key User ClassesInfrequentCommuterPwr CommutrPoliceFire & Rescu

Govt UsersEmailerBrowserTeleCommutrS

TC

Fra

cti

on

s


0

0.2

0.4


Govt UsersEmailerBrowserTeleCommutr

Morning-Afternoon

ST

C F

rac

tio

ns


0

0.25

0.5



Evening Rush

ST

C F

rac

tio

ns


0

0.2

0.4



Wee Hours

User TrafficModel

RF Model

Space-Time-Context

Space-Time-Context

Distribution

BaselineCase

AlternativeCases

Cu

mu

lati

ve

Pro

ba

bil

ity

Demand Distribution0 0.1 0.2 0.3

0

0.5

1

Key Daily EpochsMorning RushMorningLunchAfternoonPM Rush

EveningNightLate NightWee Hours

Cu

mu

lati

ve P

rob

abil

ity

(Erlangs)Pro

ba

bil

ity

De

…

Demand Distribution0 0.1 0.2 0.3 0.4

0

50

100

Key Daily EpochsMorning RushMorningLunchAfternoonPM Rush

EveningNightLate NightW ee Hours

60

Scenarios

Channel Type

NB Modem

2G Nominal

GPRS-like

3G Low

3G High

RF LAN

Wireline

1 0.7 0.2 1

0 0.2 0.1 0

0 0.1 0.1 0

0 0 0.3 0

0 0 0.3 0

0 0 0 0

0 0 0 0

A B C D

Channel Type

NB Modem

2G Nominal

GPRS-like

3G Low

3G High

RF LAN

Wireline

2400

8000

13.4K

64K

384K

7M

100M

Data Rates Fraction Per ScenarioBaseline 2G 3G 1G

Erlangcomp

Scenarios

A

B

C

D

13.53K 17.71K

21.94K 20.56K

25.18K 22.9K

69.33K 30.97K

Lost Erlangs Real Erlangs

Not PooledErlangcomp

Scenarios

A

B

C

D

4553 26.69K

8505 33.99K

10.63K 37.45K

47.85K 52.44K


Pooled

Erlangcomp

Scenarios

A

B

C

D

2811 28.43K

5713 36.78K

7305 40.78K

36.98K 63.32K


RF LANsVa4

Scenarios

A

B

C

D

29.66K 1318

38.4K 4011

42.77K 5280

65.34K 35.65K

Alt Erlangs Alt Lost

Pooled Pooled & Delay Shaped

61

KQM L Coordination

Cognitive Radio

Documents

Transcript of Cognitive Radio