Performance evaluation of cooperative and non‐cooperative MIMO cognitive radio networks

In a multiple-input multiple-output (MIMO) cognitive radio network, the cognitive users (CUs) coexist with the primary users (PUs) in the same spectrum for boosting the spectrum efficiency. Based on the informed limit of the interference power from the PUs, the CUs' compete to minimise the total interference power generated. In this study, noncooperative and cooperative game theoretic approaches are derived for network interference management (NIM). In the first scenario, the NIM problem computes the sum of minimum individual CU's interference power produced on the PU to converge to equilibrium by using the best response iteration method. The second one, NIM estimates Nash product to converge to Nash bargaining solution by using the dual decomposition method. Numerical results prove the effectiveness of the cooperative scenario that minimises the network interference power. Two new metrics are proposed to evaluate the performance in these scenarios. The interference cooperative loss metric estimates the overall network interference power loss from CUs cooperation rather than non-cooperation in the game theoretic solution. Capacity cooperative gain metric estimates the overall network capacity gain from CUs cooperation rather than non-cooperation in the game theoretic solution for a fixed acceptable interference level.