Opportunistic Role of Destination Transition Protocol for two-destinations AF relaying networks

In this paper, a new Opportunistic Role of Destination Transition Protocol (ODT) is proposed for the cooperative network with a source node and two destination nodes. As two destination nodes compete to receive the message from the source node, either of the two destination nodes can opportunely play the role of a destination and the other will serve as an amplify-and-forward relay. Particularly, the source just need to know the channel state information of each link to make role transition. In order to reveal the inherent impacts of different link statistics, we derive the closed form outage probability lower bound for ODT protocol. From the simulation results, we find that in high-SNR, the inter-destination link affects little on the ODT outage behavior when two nodes are in the downlink direction. Moreover, we demonstrate that without complicated calculation, ODT nearly has the as same effect as `5 time-slots ahead of transmission in [8]' and is also superior to schemes of predefined role configuration [1]. Theoretical analyses corroborated the correctness of the Monte Carlo simulation results.