Energy Efficiency of Holographic Transceivers Based on RIS

This work analyzes the use of reconfigurable meta-surfaces as a more energy-efficient transceiver technology than traditional active antenna arrays. A wireless link is considered, in which both the transmitter and receiver are equipped with a single antenna that illuminates a passive meta-surface placed in the vicinity of the transmit/receive antenna. The rate and energy efficiency of this system are optimized with respect to the phase shifts applied by the transmit and receive meta-surfaces. Numerical results show that the use of passive meta-surfaces can significantly improve the system energy efficiency without reducing the system rate when compared to a similar multiple-input multiple-output (MIMO) system without meta-surface.