Leveraging Large Reconfigurable Intelligent Surfaces as Anchors for Near-Field Positioning

TL;DR

This paper explores using large reconfigurable intelligent surfaces as anchors for precise near-field wireless positioning, addressing size-related uncertainties and validating the approach through theoretical bounds and simulations.

Contribution

It introduces a novel method for near-field positioning with RIS, explicitly accounting for physical size uncertainties, and derives the Cramer-Rao bound for performance analysis.

Findings

The proposed scheme achieves accurate near-field positioning.

The Cramer-Rao bound validates the scheme's effectiveness.

Numerical experiments demonstrate feasibility and potential.

Abstract

In this work, we present a recent investigation on leveraging large reconfigurable intelligent surfaces (RIS) as anchors for positioning in wireless communication systems. Unlike existing approaches, we explicitly address the uncertainty arising from the substantial physical size of the RIS, particularly relevant when a user equipment resides in the near field, and propose a method that ensures accurate positioning under these conditions. We derive the corresponding Cramer-Rao bound for our scheme and validate the effectiveness of our scheme through numerical experiments, highlighting both the feasibility and potential of our approach.