Distributed Path Selection Strategies for Integrated Access and Backhaul at mmWaves

TL;DR

This paper explores distributed path selection strategies for integrated access and backhaul in mmWave 5G networks, aiming to optimize hop count and SNR under real measurement-based channel conditions.

Contribution

It introduces novel distributed path selection techniques for IAB networks at mmWave frequencies, with analysis on their impact on hop count and bottleneck SNR.

Findings

Solutions that reduce hop count without degrading bottleneck SNR.

Guidelines for designing effective IAB path selection policies.

Performance improvements demonstrated using real measurement-based channel models.

Abstract

The communication at mmWave frequencies is a promising enabler for ultra high data rates in the next generation of mobile cellular networks (5G). The harsh propagation environment at such high frequencies, however, demands a dense base station deployment, which may be infeasible because of the unavailability of fiber drops to provide wired backhauling. To address this issue, 3GPP has recently proposed a Study Item on Integrated Access and Backhaul (IAB), i.e., on the possibility of providing the wireless backhaul together with the radio access to the mobile terminals. The design of IAB base stations and networks introduces new research challenges, especially when considering the demanding conditions at mmWave frequencies. In this paper we study different path selection techniques, using a distributed approach, and investigate their performance in terms of hop count and bottleneck Signal-to-Noise-Ratio (SNR) using a channel model based on real measurements. We show that there exist solutions that decrease the number of hops without affecting the bottleneck SNR and provide guidelines on the design of IAB path selection policies.