Radio Resource Allocation Fairness in Cooperative Cognitive Radio Relay Networks

Imbalance and unfairness in resource allocation and utilization can lead to a degraded network environment where wireless network users experience poor quality of service (QoS) within the wireless networks. In multi-user wireless radio networks with constrained wireless network resources, such as power and bandwidth resources, uniform allocation of power or bandwidth may lead to unfairness in network resource management. The cooperative cognitive radio relay networks’ (CCRRN) radio resource allocation problem among multi-users is investigated in this paper through combined resource optimization. To facilitate fairness in the multi-user networks, the maxi–min criterion is employed. The max–min fairness ensures that when the wireless network attains max–min utility fairness, no user’s utility can be improved without degrading the utility performance of any other user. To maximize the worst-case user (max–min) capacity in the CCRRN using the power and bandwidth allocation strategy, a combined optimal resource allocation (COPBA) scheme is proposed. The max–min resource allocation optimization problem developed is observed to be convex. Efficient computer-based numerical optimization solver packages, such as SNOPT, exist that can solve convex optimization problems efficiently. The MATLAB software provides a robust integrated environment where the implementation of the SNOPT solver can be executed. Using the uniform bandwidth optimal power allocation (UBOPA) scheme as a benchmark, the fairness metric of the COPBA is evaluated and compared. Furthermore, the results showed the COPBA outperforming the UBOPA scheme.