Integrated Access and Backhaul (IAB) in Low Altitude Platforms

TL;DR

This paper investigates the use of Integrated Access and Backhaul (IAB) technology in UAV-based aerial networks, proposing optimization solutions for spectrum allocation and beamforming to enhance network performance.

Contribution

It introduces a novel framework for applying IAB in UAV networks, formulating a sum-rate maximization problem with aerial backhaul constraints, and providing efficient solution methods.

Findings

IAB improves spectrum efficiency in UAV networks.

Optimized resource allocation enhances network sum-rate.

Numerical results demonstrate the effectiveness of the proposed approach.

Abstract

In this paper, we explore the problem of utilizing Integrated Access and Backhaul (IAB) technology in Non-Terrestrial Networks (NTN), with a particular focus on aerial access networks. We consider an Uncrewed Aerial Vehicle (UAV)-based wireless network comprised of two layers of UAVs: (a) a lower layer consisting a number of flying users and a UAV Base Station (BS) that provides coverage for terrestrial users and, (b) an upper layer designated to provide both wireless access for flying users and backhaul connectivity for UAV BS. By adopting IAB technology, the backhaul and access links collaboratively share their resources, enabling aerial backhauling and the utilization of the same infrastructure and frequency resources for access links. A sum-rate maximization problem is formulated by considering aerial backhaul constraints to optimally allocate the frequency spectrum between aerial and terrestrial networks. We decompose the resulting non-convex optimization problem into two sub-problems of beamforming and spectrum allocation and then propose efficient solutions for each. Numerical results in different scenarios yield insightful findings about the effectiveness of using the IAB technique in aerial networks.