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Internetes Médiakommunikáció. xxx. előadás i.) Trendek ii) Kognitív rádió (hálózat) iii) Vezeték nélküli érzékelő hálózat iv.) Kooperáció Wiener szűrés esetén Oláh András 2009. 03. 25. Trends. Home media capacity - 1975. Product Route to home Display Local storage
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Internetes Médiakommunikáció xxx. előadás i.) Trendek ii) Kognitív rádió (hálózat) iii) Vezeték nélküli érzékelő hálózat iv.) Kooperáció Wiener szűrés esetén Oláh András 2009. 03. 25.
Home media capacity - 1975 Product Route to homeDisplayLocal storage TV stations phone TV Cassette/ 8-track broadcast TV radio broadcast radio stereo Vinyl album Local news mail Advertising newspaper delivery phone Radio Stations non-electronic Tom Wolzein, Sanford C. Bernstein & Co
Home media capacity – now Product Route to homeDisplayLocal storage cable VCR TV stations phone/DSL TV Info wireless radio DVD “Daily me” broadcast TV PC Web-based storage content Server/ TiVo (PVR) Cable Nets broadcast radio stereo PC Web sites satellite monitor Local news mail headphones CD/CD-ROM Content from express delivery pager individuals iPod / storage MP3 player / iPod Peer-to-peer subcarriers / WIFI cell phone pagers - PDAs Advertising newspaper delivery phone cable box Radio stations PDA/Palm game console game console Satellite radio non-electronic Storage sticks/disks Adopted from Tom Wolzein, Sanford C. Bernstein & Co
Intelligent Device Hierarchy 2007 Potential Mobile info appliances 1.5 billion Mobile phones, PDAs, scanners, Web Tablets, GPS, etc. Human-centric Static info appliances PC’s, servers, etc. 500 million 350 million (SKUs: trillions) Vehicle cargo containers, tankers, supply chain assets (SKU)s… Mobile devices 375 million Medical Device, HVAC, industrial machinery, distributed generation… Static devices 500 million Industrial controllers, appliance controllers… Controllers Device-centric 750 million Accelerometers, pressure gauges, flow, position, speed, temp biosensors, etc. Smart sensors 35 billion 8-, 16-, 32-, 64-bit chips, etc. Microprocessors & Microcontrollers
technologies for pervasive computing RFID antenna flexible fuel cell Smart dust communications mote
x-impact technologies Source: Institute for the Future
Top Ten Technology Trends IP Will Eat Everything! – Next Generation Internet Security Is Critical Convergence of Communications & Applications Will Be A Reality – Network Will Be The Computer Wireless Internet Will Be Big – Driving Mobility Sensor Networks Will Be Everywhere e-Collaboration Will Dominate The Workplace – next generation speech recognition Broadband Will Be Common – Death of Locality Wireless & Wired Lines Will Converge – Accelerating Virtualization Knowledge Mining Will Transform the Way We Do Business Home LANs Will Proliferate – Ethernet Will Be Everywhere
What’s To Come Virtual Reality Communications Holographic storage 2020 Tele-immersion Speech Dialing Next Generation Internet 2005 IP Devices Perpendicular storage Application-aware network 2010 Flexible display Infobots 3-D printing 2015 Storage virtualization Self-healingnetworks Wearable network Fuel cells proliferate Nano computers 100 Gbyte mobile storage Intelligent optical chip Quantum Computing Gridnetworks Private on-demand reconfigurable networks 1 Tbyte mobile storage 2005 2005 2010 2015 2015 2010 Mobilevideo Cognitive radio Mesh sensory networks Over-the-air programming IP Mobility Dominant Biometrics Cloaking Emergence of Physical & Sensory Internet RFID Items Semanticweb Location-aware services 2015 Speech-to-speech translation Seamless mobility Composite applications Interactive video 2010 Wireless VoIP Video search RFID Pallets Wireless Content 2005
What’s the next big thing? Here Now • Voice over IP • P2P • Integrated GPS • WiFi • RFID • 3G Mobile • Satellite Radio / DAB • Mobile TV / IP-TV / Web TV • DTV / HDTV • PVR • Video on Demand • WiMAX • Mesh Networks • Broadband Power Line (BPL) On the Horizon • Gigabit WiMax • User Controlled Light Paths (UCLP) • Semantic Web • Bio Computing • Quantum Computing Coming Soon • 3G+ Mobile • Ultra Wide Band (UWB) • Software-Defined Radio (SDR) • Grid Computing • Sensor Networks • Nanotechnology • Internet Protocol Version 6 (IPv6) • Quantum Cryptography Access to anything, anywhere, anytime
Top-down: What the network thinks you want, when they think you want it and in the format they want TV content on cable, or over the air Radio show on radio Books in the bookstore or library Snail mail rain or shine Voice by monopoly phone provider Choice:What you want, when you want it, from anywhere All content and services available online: Music, Movies, TV Shows, Books, podcasts, Voice, TV, Radio… Choice of receptors: Personal Computers, cell-phones, Blackberry, iPods… We are moving to an EoIP world The Consumer’s Revenge!
The mobile internet revolution is here It has revolutionized communications • Mobile is supplanting wireline for telephony • The mobile web is beginning to make in-roads • Smaller, cheaper, more powerful devices • Faster, smarter radiocommunications • Result is ‘Un-tethered’ access Global Vision Mobile Internet For All ICMB 09.07.07 - 13
Spectrum challenges are now global Global and regional harmonization Technology neutrality Licence-exempt spectrum and standards Public safety & security Implications Greater effort required to build consensus (i.e. preparations for WRC) Nations can no longer operate in isolation Regional (minimum) – Global (desired) New pressures on spectrum management Cognitive Radio Challenge: develop new regulations to accommodate cognitive performance UHF White Spaces Challenge: Develop standards for use of unused broadcast spectrum for wireless broadband UWB Challenge: Develop internationally harmonized rules addressing potential interference Placing new pressures on spectrum use…
Economic System Producers & Suppliers Consumer Advocacy Groups Internet of Things Lead Users International Agencies R&D organizations Gov’t & Regulators Ethics Legal System Internet Social System Things Wireless sensors Human Body Smart tech 2G mobile Human Being 3G+ mobile Satellite RFID Nanotech xDSL WiMAN WiLAN Cable Source: ITU, 2005 Where everyone and everything is connected Ecosystem of the Internet • Radio-Frequency IDentification (RFID) tags + Smart Computing • Wireless sensors • Personal Area Networks (PANs)
‘The Internet of Things’ is a concept originally coined and introduced by MIT, Auto-ID Center and intimately linked to RFID and electronic product code (EPC) “… all about physical items talking to each other..” Like RFID it is a concept that has attracted much rhetoric, misconception and confusion as to what it means and its implications in a social context The Internet of Things
The Internet of Things*(2007 Commission view): The Internet of Things viewed as a network for communicating devices and based upon four degrees of sophistication, involving: Purely passive devices (RFID) that yield fixed data output when queried Devices with moderate processing power to format carrier messages, with the capability to vary content with respect to time and place Sensing devices that are capable of generating and communicating information about environment or item status when queried Devices with enhanced processing capability that facilitate decisions to communicate between devices without human intervention – introducing a degree of intelligence into networked systems * European Commission (2007) From RFID to the Internet of Things – Pervasive networked systems The Internet of Things
Wireless Paradigm Evolution Path 18
Wireless Paradigm Adaptive Wireless Broadband Network 구현 19
Key Technologies for Future Wireless Systems • New radios for heterogeneous access • Low-power sensor radios • High-speed WLAN and 4G/802.16 • Faster 4G cellular, 802.16, etc. • Spectrum-sharing for dense networks • Dynamic spectrum / cognitive radio for frequency coordination • Spectrum etiquette protocols • Ad-hoc wireless networks • Self-organizing networks capable of scaling organically • Discovery, MAC and routing protocols for reliable ad-hoc services • Pervasive computing software • Dynamic binding of application agents and sensors • Real-time orchestration of sensors and actuators 2007-05-09 22
Motivation • Going wireless more and more... • Lack of interoperability bw. different technologies • Lack of spectrum (???)
Spectrum Facts • Recent measurements by the FCC in the US show 70% of the allocated spectrum is not utilized • Time scale of the spectrum occupancy varies from msecs to hours • Fixed Spectrum Assignment (Existing spectrum policy forces spectrum to behave like a fragmented disk) • Bandwidth is expensive and good frequencies are taken • Unlicensed bands – biggest innovations in spectrum efficiency • More clever radio • Frequency Agility----SPECTRUM SHARING SOLUTION
Solution Joseph Mitola 1999 Cognitive Radio(CR) SDR + Intelligence Joseph Mitola 1992 Software Defined Radio(SDR) radio primarily defined in software, which supports a broad range of frequencies, and its initial configurations can be modified for user requirements.
Spectrum Sharing • Existing techniques for spectrum sharing: • Unlicensed bands (WiFi 802.11 a/b/g) • Underlay licensed bands (UWB) • Opportunistic sharing • Recycling (exploit the SINR margin of legacy systems) • Spatial Multiplexing and Beamforming • Drawbacks of existing techniques: • No knowledge or sense of spectrum availability • Limited adaptability to spectral environment • Fixed parameters: BW, Fc, packet lengths, synchronization, coding, protocols, … • New radio design philosophy: all parameters are adaptive • Cognitive Radio Technology
90 120 60 150 30 180 0 210 330 240 300 270 Channel and Interference Model • Measurement of the spectrum usage in frequency, time, and space • Wideband channel • Common with UWB • Spatial channel model • Clustering approach • Interference correlation • Derive statistical traffic model of primary users • Power level • Bandwidth • Time of usage • Inactive periods Angular domain Frequency (Hz) Time (min)
IFFT FFT D/A LEARN ENVIRONMENT TIME, FREQ, SPACE SEL FEEDBACK TO CRs ADAPTIVE LOADING QoS vs. RATE MAE/ POWER CTRL INTERFERENCE MEAS/CANCEL PA CHANNEL SEL/EST Cognitive Radio Functions • Physical Layer • OFDM transmission • Spectrum monitoring • Dynamic frequency selection, modulation, power control • Analog impairments compensation • MAC Layer • Optimize transmission parameters • Adapt rates through feedback • Negotiate or opportunistically use resources • Sensing Radio • Wideband Antenna, PA and LNA • High speed A/D & D/A, moderate resolution • Simultaneous Tx & Rx • Scalable for MIMO LNA A/D RF/Analog Front-end Digital Baseband MAC Layer
Software Defined Radio Software Routines ASICs (PHY) Programmable Hardware • Concept of SDR • Termed coined by Mitola in 1992 • Radio’s physical layer behavior is primarily defined in software • Accepts fully programmable traffic & control information • Supports broad range of frequencies, air interfaces, and application software • Changes its initial configuration to satisfy user requirements • SDR: use software routines instead of ASICs for the physical layer operations of wireless communication system 2007-05-09 32 NETLAB Seminar 7 March 2007
SDR properties Reconfigurable Easily Upgradeable Responds to the changes in the operating environment Lower maintenance cost NETLAB Seminar 7 March 2007
Advantages of SDR • Lower costs • Platform longevity, higher volume • SW has lower development costs • Time to market • Future protocols will have complex implementations • Overlap testing/development cycles • Adaptability • Standards change over time • Multi-mode operation • Sharing hardware resources • Open architecture allows multiple vendors • Maintainability enhanced 2007-05-09 34 NETLAB Seminar 7 March 2007
The Anatomy of Wireless Protocols 1. Filtering: suppress signals outside frequency band 2. Modulation: map source information onto signal waveforms 3. Channel Estimation: Estimate channel condition for transceivers 4. Error Correction: correct errors induced by noisy channel 35 NETLAB Seminar 7 March 2007
Some SDR platforms NETLAB Seminar 7 March 2007
Secondary User (Unlicensed User)Cognitive-radio enabled users Lower priority than PUs Some definitions Primary User (Licensed User)the user which has an exclusive right to a certain spectrum band. In other words, the license holders... No need to be aware of cognitive users No additional functionalities or modifications needed
SPECTRUM HOLE • A spectrum hole is a band of frequencies assigned to a primaryuser, but, at a particular time and specific geographic location,the band is not being utilized by that user.
Cognitive Radio - definitions • The term “cognitive radio” was first coined by Mitola in 1999 and can be defined as in 2006 by IEEE: “A type of radio that can sense and autonomously reason about its environment and adapt accordingly. This radio could employ machine learning mechanisms in establishing, conducting or concluding communication and networking functions with other radios” • Two CR-related standards are under development: • IEEE 802.22: high rate access (1.5 Mb/s) in rural areas up to 100 km in coverage • IEEE 802.11h: WLANs with dynamic frequency selection transmit power control capabilities
Definition (1) • In the 1999 paper that first coined the term “cognitive radio”, Joseph Mitola III defines acognitive radio as • “A radio that employs model based reasoning to achievea specified level of competence in radio-related domains.”
Definition (2) • Simon Haykin defines a cognitive radio as “An intelligent wireless communication system that is aware of its surrounding environment (i.e., outside world),and uses the methodology of understanding-by-building to learn from the environmentand adapt its internal states to statistical variations in the incoming RF stimuli by makingcorresponding changes in certain operating parameters (e.g., transmit-power, carrierfrequency,and modulation strategy) in real-time, with two primary objectives in mind: • · highly reliable communications whenever and wherever needed; • · efficient utilization of the radio spectrum.
Cognitive Radio: Contribution • Cognitive radios are a powerful tool for solving two major problems: 1) Access to spectrum (finding an open frequency and using it) 2) Interoperability (talking to legacy radios using a variety of incompatible waveforms)
Properties • Cognitive radio properties • RF technology that "listens" the spectrum • Knowledge of primary users’ spectrum usage as a function of location and time • Rules of sharing the available resources (time, frequency, space) • Embedded intelligence to determine optimal transmission (bandwidth, latency, QoS) based on primary users’ behavior • Cognitive radio requirements • co-exists with legacy wireless systems • uses their spectrum resources • does not interfere with them
Basic Cognition Cycle Spectrum Holes : A band of frequencies that are not being utilized by the primary user at a particular time and in a particular geographic location. - Black/Grey/White Holes Radio Environment (Outside World) Transmitted signal RF Stimuli Interference temperature : To quantify and manage the sources of interference in a radio environment Radio-scene Analysis (Spectrum sensing) Spectrum Holes, Noise-floor statistics Traffic statistics Transmit-power control, and spectrum management Interference temperature Channel-state estimation, and predictive modeling Quantized Channel capacity Transmitter Receiver
External Intelligence Sources Orient Establish Priority Infer on Context Hierarchy Normal Plan Generate Alternatives (Program Generation) Evaluate Alternatives Pre-process Immediate Urgent Parse Register to Current Time Learn Observe New States Receive a Message Decide Read Buttons Save Global States Prior States Alternate Resources Outside World Act Initiate Process(es) (Isochronism Is Key) Send a Message Set Display The Cognition Cycle How Does a Cognitive Radio Get So Smart? OODA loop OBSERVE-ORIENT-DECIDE-ACT
Knobs & Meters “Reading the Meters” Monitors its own performance continuously “Turning the Knobs” Responds to the operator’s commands by configuring the radio The Cognitive Engine tells the radio how to control the knobs and meters. 2007-05-09 47 47
Knobs & Meters 2007-05-09 48 48
Challenges of Cognitive Radio Hidden node problem Heterogeneous System Design 2007-05-09 49
Challenges of Cognitive Radio Frequency Assignment Negotiation of Resources (Game theory) 2007-05-09 50