Optimization Letters

, Volume 6, Issue 7, pp 1499–1511 | Cite as

Capacity optimization through sensing threshold adaptation for cognitive radio networks

  • Fotis T. Foukalas
  • George T. KaretsosEmail author
  • Lazaros F. Merakos
Original Paper


We propose capacity optimization through sensing threshold adaptation for sensing-based cognitive radio networks. The objective function of the proposed optimization is the maximization of the capacity at the secondary user subject to transmit power and sensing threshold constraints for protecting the primary user. After proving the concavity of capacity on sensing threshold, the problem is solved using the Lagrange duality decomposition method in conjunction with a subgradient iterative algorithm. The numerical results show that the proposed optimization can lead to significant capacity maximization for the secondary user as long as this is affordable to the primary user.


Capacity optimization Cognitive radio network Convex optimization Lagrange duality Subgradient method 


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Fotis T. Foukalas
    • 1
  • George T. Karetsos
    • 2
    Email author
  • Lazaros F. Merakos
    • 1
  1. 1.Department of Informatics and TelecommunicationsNational Kapodistrian University of AthensAthensGreece
  2. 2.Department of Information Technology and TelecommunicationsTEI of LarissaLarissaGreece

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