Analysis of a Token Based MAC protocol for OFDMA Cognitive Radio Environments

The radio resource shortage is one of the most important problems to be considered when deploying modern wireless telecommunication systems. A novel communication paradigm named cognitive radio, has been introduced in the last years for a more efficient exploitation of the limited available spectrum. Its main aim is to allow the co-existence of different wireless systems on the same spectral resources by limiting the mutual interference. In this paper we consider a cognitive approach environment where the primary system is an OFDMA network. In this paper a MAC protocol based on the Wireless Token Ring approach is proposed for a secondary network aiming to exploit the OFDMA framing structure of the primary network