Game-theoretic Spectrum Trading Mechanism for Cognitive Radio Networks

Inhalt:
The concept of cognitive radios has been emerged as a promising solution to the problem of inefficient spectrum utilization in wireless communication networks. In this paper, we propose a game-theoretic mechanism for the process of spectrum trading among a primary user and multiple secondary users. More particularly, it is considered an overlay cognitive radio network in which the primary user sells a portion of his licensed spectral resources to the secondary users so as to optimize his utility function. Based on the charging price and the available bandwidth, the secondary users participate in a non-cooperative game with coupled constraints in order to reach an equilibrium bandwidth allocation. Both primary and secondary users have specific BER constraints and employ adaptive coding and modulation. To simplify the computation of the Nash equilibrium of the specific game, we employ the Nikaido-Isoda function and a relaxation algorithm. The simulation results confirm that the proposed mechanism leads to an efficient allocation both for the primary and the secondary users.