Decode-amplify-forward (DAF): a new class of forwarding strategy for wireless relay channels

A new class of forwarding strategy, termed decode-amplify-forward (DAF), is proposed for relay channels. By exploiting the coding gain on the inter-user channel and maximizing the data fidelity using soft reliability representation, the proposed DAF strategy has cleverly combined the merits of both decode-forward (DF) and amplify-forward (AF). To fully harness the power promised by the DF-extended schemes such as coded cooperation, we further propose a DAF-DF mixed strategy that blends DAF and DF via time sharing. The considerable gains enabled by the proposed DAF and especially the DAF-DF strategies are demonstrated using mutual information and capacity analysis as well as extensive simulations on fast and slow fading channels.