Research Of Dynamic Spectrum Sharing And Power Allocation In Cognitive Radio Networks

Cognitive Radio Network has been proposed to meet the demand for high speed development of communication business, and it would provide solutions to the problem of not fully utilizing the scarce spectrum resoures. Algorithms based on Games Theory have been introduced for dynamic spectrum sharing and power allocation. Secondary users could access the spectrum by opportunity which improves whole spectrum usage efficiency.A novel self-adpative spectrum allocation algorithm is proposed for cognitive radio network system in which Nash Game is introduced into the model of distributed power control. We design an effective cost function for secondary users, of which there exists the Nash Equilibrium. The existence and uniqueness of Nash Equilibrium have been proved. Also, the auction based on SIR has been studied carefully to show the relation between spectrum usage efficiency and secondary users bidding strategies. Finally, double auction with belief function has been introduced for spectrum allocation while taking consideration of continous aunction periods which would bring more profits for both primary and secondary users. Simulations show that the new cost function algorithm converges faster comparing to the other two classic algorithms while the signal-to-interference ratio meets the requirement.