COGNITIVE RADIO ARCHITECTURE

Joseph Mitola III

In Cognitive Radio Architecture: The Engineering Foundationsof Radio XML, Wiley 2006

Presented by Pavlos Charalampidis

SDR (Software-Defined Radio)

Definition: A radio that is substantially defined in software, i.e.Physical Layer behavior (modulation, multiplexing, filtering etc.) isimplemented through software.

Key Technologies• High Frequency (ideally RF) ADC/DAC• DSPs• FPGAs

Advantages• Multi-mode/band/standard operation• Low cost/effort technology switches through software upgrades

SDR

CR

SDR (Software-Defined Radio)

SDR Basic Architecture

ADC

Ideal Cognitive Radio (iCR)Introduction

Definition: An autonomous agent that perceives the user’ssituation to proactively assist the user with wirelessinformation services, particularly if the user is too busy orotherwise occupied, such as when in personal distress.

Implies:• Self-awareness• Environment-awareness

OwnerPhysical environmentRF environment

Ideal Cognitive Radio (iCR)Introduction

Ideal Cognitive Radio can:• make flexible use of Radio Spectrum (e.g. SDR)• see what user sees (e.g. image/video pattern recognition)• hear what user hears (e.g. voice/speaker recognition)• protect user’s data (e.g. soft/hard biometrics & encryption)• judge Quality of Information (QoI) needed by user

in a Smart, Autonomous and Learning-capable (Cognitive) way

AUTONOMOUS MACHINE LEARNING (AML)

Ideal Cognitive Radio (iCR)Introduction

I am the COGNITIVE RADIO.

At your service Master!!!

It’s a GENIE!!!

Cognitive Radio ArchitectureSDR augmentation through CRA

Cognitive Radio ArchitectureiCR Node Functional Components

In RXML:Independency

Cognitive Radio ArchitectureFunctional Components Internal Interfaces

Cognitive Radio ArchitectureSelf-Referential Component

The Cognition Component must be able to assess, manage &control its own resources.

This can lead to Gödel-Turing paradox (unpredictable self-referential loops), i.e. system “crash”.

Reliable Watchdog Timers force time-limited computations,sufficient to perform real time communication tasks andexecute user interface functions.

Cognitive Radio ArchitectureThe Cognition Cycle

Wake Epoch

Cognitive Radio ArchitectureThe Cognition Cycle

Observation Phase:- Accept stimuli- Detect novelties

Orient Phase:- Determine significance of observation

and urgency of reaction

Planning Phase:- “Deliberate” management of stimuli,

generation/evaluation of alternatives

User SP Component/Environment Sensing Components

Stimulus RecognitionBinding (CBR-IBL)

Cognition Component

Cognitive Radio ArchitectureThe Cognition Cycle

Decision Phase:- Select among candidate plans

Action Phase:- Initiate selected processes

Learning Phase:- FUN(Observation, Decision, Planning, Action)ML techniques like Reinforcement learning, Case-based Reasoning

Externally-oriented actions (environment)

Internally-oriented actions (control radio, update internal models)

Cognition Component

Cognition/Effectors/SDR Components

Cognitive Radio ArchitectureThe Inference Hierarchy

Cognitive Radio ArchitectureThe Inference Hierarchy

Enabling Techniques:

• Natural Language Processing with

• Observe/Orient Phase lateral links for

CR logic embedded

flexible language recognition (not clear / well-structured speech)

Scene Interpretation

RF Interpretation

Cognitive Radio ArchitectureThe Inference Hierarchy

CR World Knowledge

Cognitive Radio ArchitectureIndustrial Strength iCR design rules (Synopsis)

• Use of watchdog timers when entering a cognition cycle

• Knowledge should be internalized as procedural skills

(e.g. serModels)

• Model of world treating formally time/space/RF and grounding

entities

• Models should be represented in an RKRL (e.g. RXML)

Cognitive Radio ArchitectureIndustrial Strength iCR design rules (Synopsis)

• Cognition function should:

― maintain a model of space-time

― reliably infer user’s communication context & inform SDR

― model propagation of own radio signal (estimate interference)

― infer/adjust the parameters to support running applications

― administer the computational resources

― recognize preemptive actions by user and give control to him/her