Optimal Power Allocation Functions For A Class Of Relay Selection Strategies Employing Multi-Layer Coding Approach

This study investigates the average achievable rate of a two-hop block-fading communication channel, where some single antenna relays are situated in the middle of the transmission and make the destination accessible to the transmitter. It is assumed that the transmitter as well as the relays are not aware of their corresponding instantaneous channel state information (CSI). However, a central node has the corresponding CSI of all links and selects the proper relay that best fits the provided selection criteria. By incorporating a multi-layer coding approach, which is well known to be a state-of-the-art option to deal with the lack of CSI at the transmitter, the power allocation among the code layers are derived at the transmitter as well as the selected relay node, and the effect of incorporating the aforementioned coding approach in conjunction with the provided relay selection strategies are studied. The results are also compared with that of the single-layer coding which is being served as a benchmark in this study.