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• Cognitive Radio https://store.theartofservice.com/the-cognitive-radio- toolkit.html

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Page 1: Cognitive Radio

• Cognitive Radio

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 2: Cognitive Radio

Cognitive radio

1 A 'cognitive radio' is an intelligent radio that can be programmed and configured

dynamically

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 3: Cognitive Radio

Cognitive radio - Description

1 The functions as an autonomous unit in the communications environment,

exchanging information about the environment with the networks it

accesses and other cognitive radios (CRs)

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 4: Cognitive Radio

Cognitive radio - Description

1 Some smart radio proposals combine wireless mesh network -- dynamically

changing the path messages take between two given nodes using cooperative

diversity; cognitive radio -- dynamically changing the frequency band used by

messages between two consecutive nodes on the path; and software-defined radio -- dynamically changing the protocol used by message between two consecutive nodes.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 5: Cognitive Radio

Cognitive radio - History

1 The concept of cognition|cognitive radio was first proposed by Joseph

Mitola III in a seminar at Royal Institute of Technology|KTH (the Royal Institute of Technology in

Stockholm) in 1998 and published in an article by Mitola and Gerald Q. Maguire, Jr. in 1999. It was a novel

approach in wireless communications, which Mitola later

described as:https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 6: Cognitive Radio

Cognitive radio - History

1 Cognitive radio is considered as a goal towards which a software-

defined radio platform should evolve: a fully reconfigurable wireless

transceiver which automatically adapts its communication

parameters to network and user demands.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 7: Cognitive Radio

Cognitive radio - History

1 Traditional regulatory structures have been built for an analog model and

are not optimized for cognitive radio.[http://ssrn.com/abstract=732483

Patrick S

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 8: Cognitive Radio

Cognitive radio - Terminology

1 * Full Cognitive Radio (Mitola radio), in which every possible parameter observable by a wireless node

(or network) is considered.[http://ieeexplore.ieee.org/search/srcha

bstract.jsp?arnumber=788210isnumber=17080punumber=98k2dockey=788210@ieeejrnsquery=%28%28mitola%29%3Cin%3Eau+%29pos=5access=no J. Mitola III and G. Q. Maguire, Jr., Cognitive radio: making

software radios more personal, IEEE Personal Communications Magazine, vol. 6, nr. 4, pp. 13–18,

Aug. 1999]

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 9: Cognitive Radio

Cognitive radio - Terminology

1 * Spectrum-Sensing Cognitive Radio, in which only the radio-frequency spectrum is considered.[http://ieeexplore.ieee.org/search/srchabstract.jsp

?arnumber=1391031isnumber=30289punumber=

49k2dockey=1391031@ieeejrnsquery=%28haykin+%3Cin%3E+metadata%29+%3Cand

%3E+%2849+%3Cin%3E+punumber%29pos=0access=no S. Haykin, Cognitive Radio: Brain-empowered Wireless Communications, IEEE

Journal on Selected Areas of Communications, vol. 23, nr. 2, pp. 201–220, Feb. 2005]

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 10: Cognitive Radio

Cognitive radio - Terminology

1 Other types are dependent on parts of the spectrum available for cognitive radio:

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 11: Cognitive Radio

Cognitive radio - Terminology

1 * Licensed-Band Cognitive Radio, capable of using bands assigned to

licensed users (except for unlicensed bands, such as the U-NII band or the ISM band. The IEEE 802.22 working group is developing a standard for

wireless regional area network (WRAN), which will operate on

unused television channels.[http://ieee802.org/22/ IEEE

802.22]https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 12: Cognitive Radio

Cognitive radio - Terminology

1 * Unlicensed-Band Cognitive Radio, which can only utilize unlicensed parts of the radio frequency (RF)

spectrum. One such system is described in the IEEE 802.15 Task

Group 2 specifications,[http://ieee802.org/15/pub/TG2.html IEEE 802.15.2] which

focus on the coexistence of IEEE 802.11 and Bluetooth.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 13: Cognitive Radio

Cognitive radio - Terminology

1 * Spectrum sharing: Spectrum sharing cognitive radio networks

allow cognitive radio users to share the spectrum bands of the licensed-band users. However, the cognitive

radio users have to restrict their transmit power so that the

interference caused to the licensed-band users is kept below a certain

threshold.https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 14: Cognitive Radio

Cognitive radio - Terminology

1 If the licensed users are using the bands, cognitive radio users share

the spectrum bands with the licensed users by restricting their transmit

power.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 15: Cognitive Radio

Cognitive radio - Technology

1 The chief problem in spectrum-sensing cognitive radio is designing

high-quality spectrum-sensing devices and algorithms for

exchanging spectrum-sensing data between nodes

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 16: Cognitive Radio

Cognitive radio - Technology

1 The evolution of cognitive radio toward cognitive networks is

underway; the concept of cognitive networks is to intelligently organize a

network of cognitive radios.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 17: Cognitive Radio

Cognitive radio - Functions

1 The main functions of cognitive radios are:Ian F. Akyildiz, W.-Y. Lee, M. C. Vuran, and S. Mohanty,

NeXt Generation/Dynamic Spectrum Access/Cognitive Radio Wireless Networks: A

Survey, Computer Networks (Elsevier) Journal, September 2006.

[http://www.ece.gatech.edu/research/labs/bwn/surveys/radio.pdf][http://grouper.ieee.org/

groups/scc41/files/Communications_Magazine_article_on_SCC41.pd

f Cognitive Functionality in Next Generation Wireless Networks ]

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 18: Cognitive Radio

Cognitive radio - Functions

1 ** Transmitter detection: Cognitive radios must have the capability to

determine if a signal from a primary transmitter is locally present in a

certain spectrum. There are several proposed approaches to transmitter

detection:

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 19: Cognitive Radio

Cognitive radio - Functions

1 Chen, “[http://ieeexplore.ieee.org/xpl/article

Details.jsp?reload=truearnumber=6507397 Wideband spectrum sensing for

cognitive radio networks: a survey],” IEEE Wireless Communications, vol

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 20: Cognitive Radio

Cognitive radio - Functions

1 ** Cooperative detection: Refers to spectrum-sensing methods where

information from multiple cognitive-radio users is incorporated for primary-user detectionZ. Li, F.R. Yu, and M. Huang,

“[http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5229125 A Distributed

Consensus-Based Cooperative Spectrum Sensing in Cognitive Radios],” IEEE Trans.

Vehicular Technology, vol. 59, no. 1, pp. 383-393, Jan. 2010.

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 21: Cognitive Radio

Cognitive radio - Functions

1 al ``[http://ieeexplore.ieee.org/xpl/login.jsp?tp=arnumber=4786456url=http

%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber

%3D4786456 Optimal power allocation for fading channels in

cognitive radio networks: Ergodic capacity and outage capacity], IEEE

Transhttps://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 22: Cognitive Radio

Cognitive radio - Functions

1 * Spectrum management: Capturing the best available spectrum to meet user

communication requirements, while not creating undue interference to other

(primary) users. Cognitive radios should decide on the best spectrum band (of all

bands available) to meet quality of service requirements; therefore, spectrum-

management functions are required for cognitive radios. Spectrum-management

functions are classified as:

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 23: Cognitive Radio

Cognitive radio - Cognitive radio (CR) versus intelligent antenna (IA)

1 An intelligent antenna (or smart antenna) is an antenna technology

that uses spatial beam-formation and spatial coding to cancel interference;

however, it requires an intelligent multiple- or cooperative-antenna

array. On the other hand, cognitive radio allows user terminals to sense whether a portion of the spectrum is being used to share spectrum with neighbor users. The following table

compares the two:

https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 24: Cognitive Radio

Cognitive radio - Simulation of CR Networks

1 At present, modeling and simulation is the only paradigm which allows the simulation of complex behavior in the environments

cognitive radio networks. Network simulators like OPNET, NetSim and NS2 can

be used to simulate a Cognitive radio network. Areas of research using Network simulators include a) Spectrum Sensing

incumbent detection b) Spectrum Allocation an c) Measurement and modeling of

Spectrum usage.https://store.theartofservice.com/the-cognitive-radio-toolkit.html

Page 25: Cognitive Radio

Cognitive radio - Future plans

1 IEEE 802.22: An Introduction to the First Wireless Standard based on

Cognitive Radios JOURNAL OF COMMUNICATIONS, VOL

https://store.theartofservice.com/the-cognitive-radio-toolkit.html