Noma using reconfigurable intelligent surfaces (RIS) with power adaptation and solar energy

This article derives the performance of non-orthogonal multiple access (NOMA) for cognitive networks (CNs) when the secondary source recovers power from the sun and uses power adaptation to control the interference at primary users. The secondary source signal is reflected by \(N_i\) $N_i$ of reflectors dedicated to i-th user. RIS with 8, 16, 32, 64, 128 elements enhances the throughput by 21.5, 27.5, 33.5, 39.5, 45.5 dB. We obtained up to 6 dB gain when the number of RIS reflectors is doubled.