Energy Efficiency and Optimal Resource Allocation in Cooperative Wireless Relay Networks

This paper considers using wideband slope as the measure to compare the energy efficiency between different transmission schemes for wideband cooperative wireless relay networks. Two different scenarios are considered (relay with unlimited power supply and relay with limited power supply) and two different relay strategies (amplify and forward, decode and forward) with direct transmission being used as a benchmark. The condition for getting optimal energy efficiency is obtained using theoretical analysis and simulation. The results show that (i) the source-relay distance is the most important factor influencing the energy efficiency of the whole system and (ii) the conditions for optimum energy efficiency depend on the type of relay mode.