On the Rate and Energy Efficiency Comparison of Reconfigurable Intelligent Surfaces with Relays

In this paper, we perform a performance comparison, in terms of achievable rate and energy efficiency, of a reconfigurable intelligent surface (RIS)-aided next-generation fronthaul network operating in the D band with its relay-aided counterpart. For their energy efficiency comparison, the insertion losses and power consumption of the electronic components related with the deployed nodes is taken into account. Numerical results show that the RIS-aided network outperforms the relay-aided one, both in terms of rate and energy efficiency, only for adequately large RISs.