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Joint design of routing selection and user association in multi-hop mmWave IABN: a multi-agent and double DQN framework

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The increasing demand for high-speed data services from users has promoted the exploration of high-frequency spectrum resources, and the introduction of millimeter wave (mmWave) technology provides enormous bandwidth resources for the development of 5 G and future networks. Although the densely deployed multi-hop mmWave integrated access and backhaul network (IABN) has reduced operation costs and improved spectrum utilization through efficient design, the intensification of network interference and the complexity of resource management have also been followed. Especially, how to maintain a balance of rate between the access and backhaul parts is crucial for improving the overall network throughput. Therefore, this paper investigates the joint optimization problem of routing selection and user association in multi-hop mmWave IABN. This formulated problem is essentially a mixed integer nonlinear programming (MINLP) problem under consideration of the dynamic changes in the IABN environment. Deep reinforcement learning has become a emerging method for handling complex decision problems. To this end, we propose an improved multi-agent double deep Q-network based joint optimization (MDDQJO) scheme of routing selection and user association, which aims to maximize the end-to-end throughput of the multi-hop mmWave IABN. The MDDQJO scheme adopts a load based spectrum allocation strategy to adaptively meet the traffic requirements of different nodes, and dynamically optimizes routing selection and user association decisions through parallel processing and distributed training mechanisms of all agents to respond to real-time changes in the network environment. Finally, through experimental verification, the scheme not only improves the system spectrum utilization and user service quality, but also significantly enhances the link transmission efficiency.
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Telecommunication Systems (2025) 88:21
https://doi.org/10.1007/s11235-024-01256-w
Joint design of routing selection and user association in multi-hop
mmWave IABN: a multi-agent and double DQN framework
Hu Da1,2 ·Fei Xiao2·Zhongyu Ma2·Ziqiang Zhang2·Qun Guo3
Accepted: 30 December 2024 / Published online: 20 January 2025
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025
Abstract
The increasing demand for high-speed data services from users has promoted the exploration of high-frequency spectrum
resources, and the introduction of millimeter wave (mmWave) technology provides enormous bandwidth resources for the
development of 5G and future networks. Although the densely deployed multi-hop mmWave integrated access and backhaul
network (IABN) has reduced operation costs and improved spectrum utilization through efficient design, the intensification
of network interference and the complexity of resource management have also been followed. Especially, how to maintain
a balance of rate between the access and backhaul parts is crucial for improving the overall network throughput. Therefore,
this paper investigates the joint optimization problem of routing selection and user association in multi-hop mmWave IABN.
This formulated problem is essentially a mixed integer nonlinear programming (MINLP) problem under consideration of
the dynamic changes in the IABN environment. Deep reinforcement learning has become a emerging method for handling
complex decision problems. To this end, we propose an improved multi-agent double deep Q-network based joint optimization
(MDDQJO) scheme of routing selection and user association, which aims to maximize the end-to-end throughput of the multi-
hop mmWave IABN. The MDDQJO scheme adopts a load based spectrum allocation strategy to adaptively meet the traffic
requirements of different nodes, and dynamically optimizes routing selection and user association decisions through parallel
processing and distributed training mechanisms of all agents to respond to real-time changes in the network environment.
Finally, through experimental verification, the scheme not only improves the system spectrum utilization and user service
quality, but also significantly enhances the link transmission efficiency.
Keywords MmWave IABN ·User association ·Routing selection ·DRL ·Multi-agent double deep Q-network
BZhongyu Ma
mazybg@nwnu.edu.cn
Hu Da
4942th@163.com
Fei Xiao
2022222223@nwnu.edu.cnm
Ziqiang Zhang
2023222074@nwnu.edu.cn
Qun Guo
guoqun@lut.edu.cn
1Innovation Development and Evaluation Department, Gansu
Computing Center, LanZhou 730030, China
2College of Computer Science and Engineering, Northwest
Normal University, LanZhou 730070, China
3College of Electrical and Information Engineering, Lanzhou
University of Technology, LanZhou 730050, China
1 Introduction
With the rapid development of mobile communication tech-
nology, the increasing demand for high-speed data services
from users has driven the exploration and application of high-
frequency spectrum resources. mmWave technology, with
its wide frequency band resources, is becoming the key to
the development of 5G and future networks [13]. mmWave
technology can achieve high-speed data transmission within
a narrow spectrum range, meeting users’ needs for fast
and high-capacity communication [4]. Although the high-
frequency characteristics of mmWave cause rapid attenuation
during signal propagation and high sensitivity to obstacles in
urban environments, the use of high gain directional antenna
technology [5] can effectively concentrate radiation energy,
improve signal transmission efficiency, reduce losses, and
lower interference, thereby improving communication qual-
ity and security.
123
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