Energy-efficient decode and forward relaying in diamond networks

In this paper, we study the diamond network, which consists of a sender and receiver that are physically separated (i.e. share no direct link) and use two relay nodes for wireless communication. Under a specific decode-and-forward relaying scheme (Multi-hopping Decode-and-Forward, MDF), we consider the problem of an energy-efficient operation of the channel and derive algorithms that maximize the spectral efficiency for specified energy-per-bit bounds. Moreover, we give an algorithm that solves the minimum energy problem for a given target spectral efficiency under the assumption of equal power allocation at the relays.