Energy efficiency and spectrum efficiency balance of wireless relay networks

A new method to improve Energy Efficiency (EE) in an energy-constrained wireless relay network is presented. In this network, the source nodes transmits signals through flat fading channels to a set of intermediate relay nodes which amplify signals and then forward them to the destination through other flat fading channels. The distances among source relay and destination are considered. Since the total network energy enhancement depend on the relay energy consumption which in turn depends on the users transmit powers and the geographic of relays location, the proposal method aims to optimize relay location for improving EE with the lowest sacrifice in the Spectrum Efficiency (SE). Analytical expressions for optimal relay location with balanced EE SE are derived and fully verified by simulation results.