Simple overview to Cognitive Radio

1. Cognitive Radio
By
Mohammed AbouHaggar

2. Spectrum Crunch
• Spectrum crunch refers to the potential lack of
sufficient wireless frequency spectrum needed to
support a growing number of consumer devices.
• Spectrum crunch is a risk in telecommunications
and wireless networking with profound
implications for the immediate future.
• We need more spectrum but resources is finite
and limited.

3. Cognitive Radio
• Has many definitions :
• FCC: CR is a radio that can change its
transmitter parameters based on interaction
with the environment.
• NTIA: A radio system that senses its
operational electromagnetic environment and
can dynamically and autonomously adjust its
radio operating parameters to modify system
operation, such as maximize throughput,
mitigate interference, facilitate
interoperability.

4. What all definitions agreed ?
• Radio.
• Sensing
• Decision making Automaticity.
• Adaptation.
• Learning: ability to
recognize common user activities so
that it begins to learn to assist the use
and the network with common tasks

5. Features

6. How it works

7. Spectrum Holes
• Dynamic spectrum access is
a new spectrum sharing
paradigm that allows
secondary users to access
the abundant spectrum holes
or white spaces in the
licensed spectrum bands.

11. History
• The first appearance of CR term
was with J.Mitola year 2000.
• While developing software for a
radio system ,he tried to join AI
with radio hence CR born.
• Haykin put 2005 a complete
vision of CR .

12. Haykin Vision J.Mitola

13. Software-defined radio (SDR)
• A radio communication system where components that have been
typically implemented in hardware (e.g. mixers, filters, amplifiers,
modulators/demodulators, detectors, etc.) are instead implemented by
means of software on a personal computer or embedded system.
• A basic SDR system may consist of a personal computer equipped with
a sound card, or other analog-to-digital converter, preceded by some
form of RF front end. Significant amounts of signal processing are
handed over to the general-purpose processor, rather than being done
in special-purpose hardware (electronic circuits).
• Such a design produces a radio which can receive and transmit widely
different radio protocols based only on the software used.

14. What can CR do ?

18. Application - QOSMOS

19. Challenges
• Let us admit that Cognitive Radio technology is not-yet-mature,
and is still under active research both for implementing its H/W
and S/W counterparts Some of the biggest challenges that faces
the development of the Cognitive Radio areas follows:
• Specific Hardware.
• Synchronization.
• Vulnerabilities.
• False alarms.
• Hidden nodes.