Beamforming Design and Performance Evaluation for RIS-aided Localization using LEO Satellite Signals

TL;DR

This paper proposes an RIS beamforming method to enhance LEO satellite-based localization accuracy, achieving potentially sub-meter precision by optimizing signal design and evaluating performance through the Cramér-Rao bound.

Contribution

It introduces an optimal RIS beamforming approach for LEO satellite localization and derives the associated Cramér-Rao bound to guide design improvements.

Findings

Proposed beamforming outperforms benchmark schemes

Achieves meter or sub-meter localization accuracy

Demonstrates synergy between LEO satellites and RISs

Abstract

The growing availability of low-Earth orbit (LEO) satellites, coupled with the anticipated widespread deployment of reconfigurable intelligent surfaces (RISs), opens up promising prospects for new localization paradigms. This paper studies RIS-aided localization using LEO satellite signals. The Cram\'er-Rao bound of the considered localization problem is derived, based on which an optimal RIS beamforming design that minimizes the derived bound is proposed. Numerical results demonstrate the superiority of the proposed beamforming scheme over benchmark alternatives, while also revealing that the synergy between LEO satellites and RISs holds the promise of achieving localization accuracy at the meter or even sub-meter level.