Efficient Beam-Forming for Maximum Outage of Cognitive Relay Networks

We consider the scenario of cognitive relay networks, where the cognitive relay is equipped with multiple antennas and the cognitive destinations have only one antenna due to the size and cost limitations. Aiming to maximize the signal-to-interference noise ratio (SINR), we develop the optimal beam-forming scheme for the relay case. The proposed scheme is based on minimum mean square error (MMSE). The theoretical results are validated by simulations. Simulation results show that the proposed scheme has a considerable performance.