Optimal packet length for reconfigurable intelligent surfaces (RIS) using NOMA with energy harvesting from a water flow

In this article, we compute the performance of Reconfigurable Intelligent Surfaces (RIS) using Non Orthogonal Multiple Access (NOMA) and power harvesting from a water flow. The harvested power from a water is related to water velocity that has a Gaussian distribution. The harvested power is used by the source to forward data to K users using RIS. The source signal is reflected by some reflectors dedicated to K users. We select the harvesting time to enhance the throughput. The results consider Rayleigh channels with any position of the source and NOMA users. The results are confirmed with computer simulations. We also optimize packet length to maximize the average total throughput.