Cognitive radio in a frequency planned environment can it work erik axell
Download
1 / 12

Cognitive Radio in a Frequency-Planned Environment: Can it Work? Erik Axell - PowerPoint PPT Presentation


  • 97 Views
  • Uploaded on

Cognitive Radio in a Frequency-Planned Environment: Can it Work? Erik Axell. Erik G. Larsson and Mikael Skoglund, IEEE GLOBECOM, 2007. SENDORA – SEnsor Network for Dynamic and cOgnitive Radio Access. Linköping University THALES Communications Institut Eurocom Kungliga Tekniska Högskolan

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Cognitive Radio in a Frequency-Planned Environment: Can it Work? Erik Axell' - melyssa-patterson


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Cognitive radio in a frequency planned environment can it work erik axell

Cognitive Radio in a Frequency-Planned Environment: Can it Work?Erik Axell

Erik G. Larsson and Mikael Skoglund, IEEE GLOBECOM, 2007


Sendora sensor network for dynamic and cognitive radio access
SENDORA – SEnsor Network for Dynamic and cOgnitive Radio Access

  • Linköping University

  • THALES Communications

  • Institut Eurocom

  • Kungliga Tekniska Högskolan

  • Helsinki University of Technology

  • Norwegian University of Science and Technology

  • Telenor ASA

  • Universitat de València

  • Università degli Studi di Roma


The scenario
The Scenario Access


Some fundamental questions
Some Fundamental Questions Access

  • Cognitive radios must transmit at very low power. How low must it be?

  • Cognitive radios must expect very low C/(I+N) from primary system. What orders of magnitude?

  • At an acceptable loss in primary system coverage, how large is the “area of cognitive operation”?


Basic assumptions and some terminology
Basic Assumptions and Some Terminology Access

  • Path loss and lognormal fading

  • n-reuse frequency planning for primary system

  • SINR for primary system, with primary base station power P0

  •  -SINR is the SINR achieved with probability 1-


Primary system operating point
Primary System Operating Point Access

  • Primary system is either noise limited, interference limited, or in-between. Quantify this in terms of ratio between noise and co-channel interference at the primary cell border:

    •  - [dB]: purely noise limited

    •   [dB]: purely interference limited


With cognitive users
With Cognitive Users Access

  • SINR is now

  • Suppose we can accept reduction in primary cell radius from r to r’. Then assume M cognitive users, each with power P, uniformly distributed in circular ring. How large can the circular ring, the ”area of cognitive operation,” be?





Asymptotic sensitivity requirements
Asymptotic Sensitivity Requirements Access

  • The additional (compared to primary receivers) sensitivity requirement  isand satisfies


Main conclusions
Main Conclusions Access

  • If cognitive users are to be introduced, they must

    • Be few in numbers, since the aggregate power scales with the number of devices

    • Transmit with extremely low power, such as -30 dB below the primary system

    • Have very sensitive radios, in the order of 20-30 dB more sensitive than the primary system radios.