1. Cognitive radio network (CR)
Prepared by :
Ola Mashaqi
Suhad Malayshi
Submitted to Dr. Saed Tarapiah

2. Topics to be discussed
1.
What is CR Network
2.
CR antennas
3.
CR mechanism
4.
CR network accessibility, adaptively ,scalability , reliability
and Interconnectivity
5. How Cognitive Radio Works
5.
Cognitive Radios vs. Conventional Radios
6.
Cognitive Radio benefits
7.
Application of cognitive radio

3. What is CR Network ?
CR able to monitor, sense, and detect the conditions of
their operating environment, and dynamically
reconfigure their own characteristics to best match
conditions
those conditions
Interference… path loss.. shadowing …multipath fading

4. CONT.
CR can be defined as “…a radio that is aware of
its surroundings and adapts intelligently”.
Cognitive radio networks, like xG’s xMax system,
represent an innovative approach to wireless
engineering in which radios are designed with
an unused level of intelligence

5. intelligence at all the 7 layers of the
“OSI” model.
CR uses intelligent
signal processing (ISP)
at the physical layer of a
wireless system and is
achieved by combining
ISP with software
defined radio (SDR)

6. CR network mechanism
1.Sense ->
Sensing antenna
2.Analyze
3.Decide
4.Tune in ->
Reconfigurable
antenna

7. CR ANTENNAS
“ Sensing antenna” Wide band
antenna which
Continuously monitors The frequency spectrum for activity
“ Reconfigurable antenna” narrow-band antenna which
dynamically tune to a specific range within the frequency
spectrum to perform data transfer

8. C. R. Network improve ACCESSIBILITY
access various networks and services

9. C. R. Network improve ADAPTABILITY
When user roams across borders, the device performs selfadjustment to stay in submission with local radio operations
and emissions regulations.

10. C. R. Network improve INTERCONNECTIVITY
multi-terminal / multi-frequency communication devices.

11. C. R. Network improve SCALABILITY
The network can potentially scale to large numbers of users

12. C. R. Network improve RELIABILITY
self-configuringmesh wireless networks avoid failure by rerouting around node failures or congestion areas

13. How Cognitive Radio Works

14. How Cognitive Radio Works
• Using complex calculations, cognitive radios can identify
potential impairments to communications quality in their
environment, for example, interference, path loss,
shadowing and multipath fading
• They can then adjust their transmitting parameters, such as
power output, frequency, and modulation to ensure an
optimized communications experience for users

15. Cognitive Radios vs. Conventional Radios
Conventional
Cognitive
• operating in interference-free
spectrum
• Unable to dynamically change
parameters, channels or
spectrum bands in response to
interference
• View congested radio spectrum
as essentially unusable for
communications due to heavy
interference
•
function in challenging
conditions
• quickly identify unused “gaps” in
spectrum that are not being used
• find and tune to other
spectrum if interference is
detected on the frequencies
being used (example - xMax
samples, detects and
determines if interference has
reached unacceptable levels
up to 33 times a second)

16. Cognitive Radios vs. Conventional Radios

18. We have to mention …
• xG Technology, Inc is The company developed cognitive
radio technology
• xG’s initial product is xMax, a carrier-class cognitive radio
Network
• These achievements have been generated by the company’s
$100 million plus investment in both its own extensive R&D
activity and international partnering efforts

19. Comparison

20. Cognitive Radio Benefits
►Designed to meet all FCC
►Able to identify “clean” frequencies, and to quickly tune to those
frequencies
►Interference-free operation
►Can adapt dynamically to maximize throughput (and/or range)
►Compact access points (14 simultaneous calls, 6 Mbps raw data rate)
►Easy to engineer and install

21. Application of cognitive radio

22. Summary
The term Cognitive Radio was first suggested by prof. Joseph Mitola
1999
controlled by powerful microprocessors which have been
programmed to analyze a number of the radio channel
parameters.
The key feature of a Cognitive Radio is its ability to recognize the
unused parts of spectrum that is licensed to a primary user and adapt
its communication strategy to use these parts while minimizing
the interference that it generates to the primary user.
ThanQ