Balancing energy efficiency and spectrum efficiency for lower error rate in bidirectional relay networks

A scheme for combining data rate, energy efficiency and relay location in bidirectional amplify-and-forward relay networks is proposed in this paper. The proposed scheme allows the energy consumption to be evaluated for all positions of a chosen relay along a line between the transmitter and the destination. Furthermore, the evaluated energy reduction is used to obtain the optimal balance between the energy efficiency (EE) and spectrum efficiency (SE). This balance enables the EE to increase significantly with the least loss of SE. Such a balance is then expressed with respect to the bit error rate. Numerical examples are provided to validate the analysis.