Low-Power Double RIS-Assisted Mobile LEO Satellite Communications

TL;DR

This paper introduces a low-power LEO satellite communication system using double RIS to improve energy efficiency and signal quality, achieving significant power reduction through dual-stage beamforming.

Contribution

It presents a novel architecture with double RIS in near-field and far-field, along with a path loss model and beamforming techniques for energy-efficient satellite communication.

Findings

Achieves 40 dB power reduction in uplink

Demonstrates effectiveness with a small RIS of 0.25 m²

Enhances energy efficiency in LEO satellite links

Abstract

We propose a low-power mobile low earth orbit (LEO) satellite communication architecture, employing double reconfigurable intelligent surfaces (RIS) to enhance energy efficiency and signal performance. With a distance between RISs that satisfies the far-field requirement, this architecture positions one small RIS each in the near-field of the satellite's antenna and the user on the ground. Moreover, we develop a path loss model for the double-RIS communication link, considering the near-field and far-field effects. Further, with the help of dual-stage beamforming, the proposed system maximizes the signal power and minimizes power consumption. Simulation results show that the proposed architecture can reduce the power consumption with 40 dB in the uplink, with a small $0.25^2$ $\text{m}^2$ RIS near the user, to communicate in energy-constrained LEO satellite communication circumstances.