The disadvantage of the wireless networks used these days, that they utilize traditional spectrum allocation techniques, therefore they are not able to adapt to the continuously changing environmental conditions. Additional drawback of this traditional method, that the spectrum holes - spectrum opportunities - cannot be used by secondary users while the primary users – who have the license over the spectrum – are inactive. Cognitive radio technique, which is a new paradigm in the development of wireless networks, try to provide a solution to handle these problems. The goal of such systems is to extend the effective usage of radio resources, therefore the scarce spectrum and the rapid development of mobile user needs mean a huge help in its spreading.
In the analysis and design of wireless communication networks, game theory is more and more instrumental. The reason is, that in a game theoretical model the players try to maximize their utilities based on private information, so it is perfectly capable to examine decentralized networks.
In the first place, I present in my thesis the basic concepts of game theory and its applications in communication networks. After these chapters, I review the operation and main features of cognitive radio technique, as well as proprietary systems using these technologies. In the next chapter, I describe a decentralized dynamic spectrum access model which uses game theoretical approaches. This model is the basis of my simulation environment which I use to test the number of collisions, the utility of radios and the accuracy of contention estimates. Finally, I evaluate the results of the simulations and propose further development opportunities.