Frequency-Mixing Intelligent Reflecting Surfaces for Nonlinear Wireless Propagation

TL;DR

This paper proposes a novel frequency-mixing intelligent reflecting surface (FMx-IRS) that introduces nonlinearity into wireless propagation by continuously changing phases, enabling new control over signal frequencies and channel characteristics.

Contribution

The paper introduces the FMx-IRS concept, demonstrating its ability to create nonlinear propagation environments and offering new degrees of control over wireless channels.

Findings

FMx-IRS acts as a frequency mixer creating new frequencies.

The architecture enables channel decoupling and correlation control.

Simulations validate the advantages of the proposed concept.

Abstract

We introduce the concept of frequency-mixing intelligent reflecting surface (FMx-IRS), where the elements of the surface continuously change the phases of the incident signals. In this way, the FMx-IRS acts as a frequency mixer and makes the propagation environment nonlinear, thereby introducing new frequencies. We study the basic features of the proposed concept and demonstrate its advantages that stem from the novel type of control over the wireless propagation. The channel decoupling feature and the correlation between reflected channels are elaborated for the architecture, and are validated by the simulations.