End-to-End Mutual Coupling Aware Communication Model for Reconfigurable Intelligent Surfaces: An Electromagnetic-Compliant Approach Based on Mutual Impedances
A physics and electromagnetic (EM) compliant communication model for analyzing and optimizing RIS-assisted wireless systems and accounts for the intertwinement between the amplitude and phase response of the unit cells of the RIS.
Abstract
Reconfigurable intelligent surfaces (RISs) are an emerging technology for application to wireless networks. We introduce a physics and electromagnetic (EM) compliant communication model for analyzing and optimizing RIS-assisted wireless systems. The proposed model has four main notable attributes: (i) it is end-to-end , i.e., it is formulated in terms of an equivalent channel that yields a one-to-one mapping between the voltages fed into the ports of a transmitter and the voltages measured at the ports of a receiver; (ii) it is EM-compliant , i.e., it accounts for the generation and propagation of the EM fields; (iii) it is mutual coupling aware , i.e., it accounts for the mutual coupling among the sub-wavelength unit cells of the RIS; and (iv) it is unit cell aware , i.e., it accounts for the intertwinement between the amplitude and phase response of the unit cells of the RIS.