Relay selection algorithm with limited feedback precoding for MIMO multiple relay channels

Considering Amplify-and-Forward cooperative network with the help of one or more relay nodes, a relay selection algorithm with Grassmannian beamforming precoder is proposed for the two-hop half-duplex relay channels. This new algorithm, which choose only one relay with the maximal received SNR gain to assist in transmission, can significantly reduce the required number of feedback bits, achieve excellent outage behavior and average throughput, and maintain full diversity order. Simulation results demonstrate that the performance of the proposed scheme approaches to the optimal full feedback scheme with a low complexity, and for actual situation with distance attenuation factor, the performance advantage is also in existence.