Performance Analysis for Reconfigurable Intelligent Surface Assisted MIMO Systems

TL;DR

This paper analyzes the maximal achievable rate of RIS-assisted MIMO systems at finite blocklengths, providing bounds and demonstrating the impact of channel variance on performance convergence.

Contribution

It introduces finite blocklength bounds for RIS-assisted MIMO systems using advanced probabilistic tools, advancing understanding of their performance limits.

Findings

Fast convergence of achievable rate with increasing blocklength

Channel variance effectively measures backoff from maximal rate

Finite blocklength bounds are validated through numerical evaluation

Abstract

This paper investigates the maximal achievable rate for a given average error probability and blocklength for the reconfigurable intelligent surface (RIS) assisted multiple-input and multiple-output (MIMO) system. The result consists of a finite blocklength channel coding achievability bound and a converse bound based on the Berry-Esseen theorem, the Mellin transform and the mutual information. Numerical evaluation shows fast speed of convergence to the maximal achievable rate as the blocklength increases and also proves that the channel variance is a sound measurement of the backoff from the maximal achievable rate due to finite blocklength.