RIS-Empowered LEO Satellite Networks for 6G: Promising Usage Scenarios and Future Directions

TL;DR

This paper explores how reconfigurable intelligent surfaces (RISs) can enhance low-Earth orbit satellite networks, addressing their limitations and enabling promising applications for future 6G wireless connectivity.

Contribution

It provides a comprehensive overview of RIS technology in LEO satellite networks, discusses potential applications, and outlines future research directions for 6G integration.

Findings

RISs can improve link quality and reduce Doppler effects.

RIS deployment can mitigate interference in LEO satellite links.

The paper identifies promising scenarios for RIS-enabled LEO networks.

Abstract

Low-Earth orbit (LEO) satellite systems have been deemed a promising key enabler for current 5G and the forthcoming 6G wireless networks. Such LEO satellite constellations can provide worldwide three-dimensional coverage, high data rate, and scalability, thus enabling truly ubiquitous connectivity. On the other hand, another promising technology, reconfigurable intelligent surfaces (RISs), has emerged with favorable features, such as flexible deployment, cost & power efficiency, less transmission delay, noise-free nature, and in-band full-duplex structure. LEO satellite networks have many practical imperfections and limitations; however, exploiting RISs has been shown to be a potential solution to overcome these challenges. Particularly, RISs can enhance link quality, reduce the Doppler shift effect, and mitigate inter-/intra beam interference. In this article, we delve into exploiting RISs in LEO satellite networks. First, we present a holistic overview of LEO satellite communication and RIS technology, highlighting potential benefits and challenges. Second, we describe promising usage scenarios and applications in detail. Finally, we discuss potential future directions and challenges on RIS-empowered LEO networks, offering futuristic visions of the upcoming 6G era.