# Integration of Satellites in 5G through LEO Constellations

## TL;DR

This paper explores integrating LEO satellite constellations with 5G networks to enhance global connectivity, addressing satellite channel challenges and proposing solutions for key PHY and MAC procedures.

## Contribution

It introduces a heterogeneous 5G architecture with LEO satellites providing backhaul, analyzing satellite channel impacts, and proposing tailored PHY and MAC solutions.

## Key findings

- Satellite channels cause significant delays and Doppler shifts.
- Proposed solutions improve random access and waveform handling.
- Enhanced procedures support satellite-terrestrial integration.

## Abstract

The standardization of 5G systems is entering in its critical phase, with 3GPP that will publish the PHY standard by June 2017. In order to meet the demanding 5G requirements both in terms of large throughput and global connectivity, Satellite Communications provide a valuable resource to extend and complement terrestrial networks. In this context, we consider a heterogeneous architecture in which a LEO mega-constellation satellite system provides backhaul connectivity to terrestrial 5G Relay Nodes, which create an on-ground 5G network. Since large delays and Doppler shifts related to satellite channels pose severe challenges to terrestrial-based systems, in this paper we assess their impact on the future 5G PHY and MAC layer procedures. In addition, solutions are proposed for Random Access, waveform numerology, and HARQ procedures.