Maximizing Energy-Efficiency in Multi-Relay OFDMA Cellular Networks
This contribution presents a method of obtaining the optimal power and subcarrier allocations that maximize the Energy-Efficiency (EE) of a multi-user, multi-relay, Orthogonal Frequency Division Multiple Access (OFDMA) cellular network. Initially, the Objective Function (OF) is formulated as the ratio of the Spectral-Efficiency (SE) over the power consumption of the network. This OF is shown to be quasi-concave, thus Dinkelbach's method can be employed for solving it as a series of parameterized concave problems. The authors characterize the performance of the aforementioned method by comparing the optimal solutions obtained to those found using an exhaustive search.