Grant-Free Coexistence of Critical and Noncritical IoT Services in Two-Hop Satellite and Terrestrial Networks

Terrestrial and satellite communication networks often rely on two-hop wireless architectures with an access channel followed by backhaul links. Examples include cloud-radio (C-RAN) low-Earth orbit (LEO) systems. Furthermore, services characterized the coexistence of heterogeneous requirements are emerging as key use cases. This article studies performance critical service (CS) non-CS (NCS) for Internet-of-Things (IoT) systems sharing a grant-free consisting radio segments. On segment, IoT devices send packets to set noncooperative points (APs) using slotted ALOHA (SA). The APs then forward correctly received messages base station over shared segment adopting SA. We study first simplified erasure model, which is well suited applications. Then, in order account terrestrial scenarios, impact fading considered. Among main conclusions, we show that orthogonal interservice resource allocation generally preferred NCS devices, while nonorthogonal protocols can improve throughput packet success rate CS both scenarios.