A relay selection scheme with limit feedback in OFDM relay networks based on subcarrier mapping

Subcarrier mapping (SCM) is an efficient way to evidently improve the average end-to-end capacity in cooperative OFDM networks. However perfect channel knowledge is required, which leads to large feedback amount of channel state information (CSI). In this paper, the uplink scenario of multi-relay OFDM cooperative networks with subcarrier mapping scheme is considered. An opportunistic relaying strategy with limit feedback CSI is proposed. The transmission scheme, which is based on instantaneous channel quality, is selected to offer maximum the end-to-end system capacity. The simulations show that the proposed approach can achieve almost asymptotically performance as full CSI feedback scheme with large number of subcarriers.