Reconfigurable Intelligent Surface Enhanced NOMA Assisted Backscatter Communication System

To enhance the backscatter-links with double fading effect in non-orthogonal multiple access assisted backscatter communication (NOMABC), a new reconfigurable intelligent surface (RIS) enhanced NOMABC (RIS-NOMABC) system is proposed. A joint optimization problem over power reflection coefficients at devices (BDs) and phase shifts RIS formulated. solve this non-convex problem, low complexity algorithm proposed by invoking alternative optimization, successive convex approximation manifold algorithms. Numerical results corroborate that RIS-NOMABC outperforms conventional without RIS, demonstrate feasibility effectiveness of algorithm.