Copula-Based Modeling of RIS-Assisted Communications: Outage Probability Analysis

TL;DR

This paper introduces a copula-based statistical model to analyze the outage probability of RIS-assisted communications with phase noise, capturing complex dependencies caused by discrete phase shifters.

Contribution

It presents a novel copula modeling approach to characterize the dependence structure of SNR in RIS systems with finite resolution phase shifters, providing closed-form outage probability expressions.

Findings

Closed-form outage probability expressions validated by numerical results.

Copula modeling effectively captures dependence due to phase noise.

Supports further RIS research with joint distribution analysis.

Abstract

Statistical characterization of the signal-to-noise ratio (SNR) of reconfigurable intelligent surface (RIS)-assistedcommunications in the presence of phase noise is an important open issue. In this letter, we exploit the concept of copula modeling to capture the non-standard dependence features that appear due to the presence of discrete phase noise. In particular,we consider the outage probability of RIS systems in Rayleighfading channels and provide joint distributions to characterize the dependencies due to the use of finite resolution phase shifters at the RIS. Numerical assessments confirm the validity of closed-form expressions of the outage probability and motivate the use of bivariate copula for further RIS studies.