Relay selection in non-reciprocal TWRNs with limited feedback

This paper investigates the problem of relay selection in a non-reciprocal two-way relay network. To achieve full diversity, relay selection at a central node needs to gather all the instantaneous channel state information (CSI). Assume one of the source nodes is the central node, to make an accurate decision this node needs some more CSI which can not be estimated from the received signal. To solve this problem we can feed back the required CSI from the other source node. To effectively transmit the CSI, two quantization schemes, Llyod-Max and uniform quantization, are considered in this paper. In order to further improve the performance, some modified quantization methods are designed to adjust the quantization range. Simulation results indicate the effectiveness of the proposed schemes.