Achieving fairness in distributed cognitive radio networks using a timer mechanism

We consider the issue of fairness in scheduler design for distributed cognitive radio networks (CRN). We first distinguish between intra- and inter-class fairness as a result of hierarchical resource access right in a secondary spectrum allocation regime. Further, we develop a timer mechanism to achieve round-robin, max-min and proportional fairness for intra-class scheduling in a CRN. The case of inter-class fairness is a addressed by defining a time bias to prioritize the resource access of primary links. Numerical results show that proportional fair scheduling sustains a good level of performance for both intra and inter-class fairness.