Resource Allocation with MAC Layer Node Cooperation in Cognitive Radio Networks

An algorithm for cooperative Dynamic Spectrum Access in Cognitive Radio networks is presented. The proposed algorithm utilizes Medium Access Control layer mechanisms for message exchange between secondary nodes thatoperate in license exempt spectrum bands, in order to achieve interference mitigation. A fuzzy logic reasoner isutilized in order to take into account the effect of the coexistence of a large number of users in the interference aswell as to cope for uncertainties in the message exchange, caused by the nodes' mobility and the large delays inthe updating of the necessary information. The proposed algorithm is applied in Filter Bank Multicarrier, as wellas Orthogonal Frequency Division Multiplexing systems, and its performance is evaluated through extensivesimulations that cover a wide range of typical scenarios. Experimental results indicate improved behaviourcompared to previous schemes, especially in the case of uncertainties that cause underestimation of theinterference levels