Outage and Energy Efficiency Analysis for Active RIS-Assisted SWIPT Under Nonlinear EH

This paper investigates an active RIS transmission for energy-sustainable 6 G consumer communications. A practical nonlinear energy harvesting (EH) model is adopted at the end users, whereas the outage probability and user-centric energy efficiency (UEE) are discussed with the small-scale and large-scale fading channel. Simulation results verify the analytical accuracy and reveal that moderate amplification significantly improves both reliability and UEE. The considered system achieves more than an order-of-magnitude reduction in outage probability over passive RIS. According to the simulations, it can be found that the excessive amplification leads to noise enhancement and EH saturation, resulting in degraded performance. These findings highlight the existence of an optimal amplification regime and confirm the potential of active RIS as a practical and energyefficient solution for$\mathbf{6 G}$consumer communications.