Resource allocation for heterogeneous cognitive radio networks

Cognitive radio (CR) network is currently an emerging technology for future wireless communications. In this paper, the problem of resource allocation for heterogeneous users in an underlay CR network is addressed. The objective is to maximize the weighted sum of the data rate for all the categories of secondary users within the network. The problem is first formulated as a non-linear optimization problem which is non-deterministic polynomial-time (NP) hard. The problem is then cleverly re-formulated as an integer linear programming problem and solved through branch-and-bound method. The impact of the weights on the different categories of users is also investigated. The results obtained show that through the approach developed by the authors, optimal resource allocation is achievable for heterogeneous CR networks.