Energy-efficient MMSE beamforming and power allocation in multibeam satellite systems

In current satellite communication systems, energy efficiency is of paramount importance since it strongly affects the satellite size and lifetime. In this paper, the energy efficiency of a multibeam downlink system is investigated in terms of maximizing the ratio of system throughput over consumed power. More specifically, the consumed power comprises both operating power which is needed for running the network equipment and transmit power which is needed for forwarding the information to the end users. Regarding the employed transmission technique, Minimum Mean Square Error (MMSE) beamforming together with power optimization for satellite downlink channel is used while full frequency reuse is assumed. By varying the ratio of operating and transmit power, we study the performance of the forward link in terms of spectral and energy efficiency.