Stability Throughput Analysis of Cognitive Radio Interference MIMO Channels

This paper developed a framework to analyze the performance gain in multiple-input multiple-output (MIMO) systems together with cognitive radio (CR) interference communication systems based on average channel state information (CSI). Because of interference between the cognitive user and the licensed user, the cognitive user must optimize its power to ensure the licensed user´s transmission stability. Firstly, we derived close-form expression of the outage and throughput both for licensed user and cognitive user under Reighlay fading channel environment. Then, the maximum stability throughput for the cognitive user is derived under the conditions of stability of the licensed user (a fixed throughput selected by the licensed user) under flat-fading Rayleigh channel conditions. We studied the optimal problem both in the ideal system which assumes that the detection is always correct and the real system in which interference exist between the cognitive user and the licensed user because of channel fading.