Quantification of Throughput Enhancement using Cooperative Communication in Cognitive Radio Networks

In this paper, we study the throughput enhancement achieved by cooperative communication technique in cognitive radio networks for different global objectives and constraints. The secondary network coordinator distributes the nodes among the available channels and pairs them in a cooperative collation to enhance their transmission characteristics. The coordinator objective is to maximize the total throughput or to achieve a fair distribution of the available resources under some minimum throughput demand constraints. We formulate the optimization problems for different throughput objectives in the cooperative and non-cooperative modes. The results show a noticeable enhancement in the total throughput achieved by the network as well as the slow node in the cooperative mode compared to the non-cooperative one. Also, the proportional fairness, and maximizing the minimum user throughput objectives gives a fair distribution for the available resources which significantly enhances the throughput of the slow nodes compared to the case when the objective is to maximize the total throughput.