Resource Allocation and Multi-Connectivity Operation in Cellular IAB Networks
Sadovaya, Yekaterina (2021)
2021
Master's Programme in Information Technology
Informaatioteknologian ja viestinnän tiedekunta - Faculty of Information Technology and Communication Sciences
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Hyväksymispäivämäärä
2021-08-26
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tuni-202108126532
https://urn.fi/URN:NBN:fi:tuni-202108126532
Tiivistelmä
The emerging 5G technology promises a capacity boost for future cellular networks due to the utilization of the millimeter-wave (mmWave) spectrum. However, radio propagation over mmWave bands implies higher propagation losses, resulting in reduced coverage for the 5G base station (gNB); thus, deployments become ultra-dense. Under the described conditions, using conventional wired backhaul may not be cost-efficient for network operators. Therefore, the concept of wireless backhaul is being considered by 3GPP, which is called integrated access and backhaul (IAB).
On the one hand, this technology allows the deployment cost to be reduced. On the other hand, wireless backhaul raises multiple challenges. This includes the half-duplex constraint, which complicates the resource allocation procedure. In addition, the inherent properties of mmWave frequencies make a wireless connection more susceptible to blockage. Therefore, this study characterizes resource allocation, interference, and blockage avoidance techniques in the context of IAB networks.
The results of the research demonstrate that interference caused by mutual reception at the IAB node can be avoided using spatial diversity. The critical angular distance of more than 25 deg. is identified as the point at which mutual receptions start to influence each other. The dynamic resource allocation scheme is proposed, which enables load balancing in IAB networks limited by the half-duplex constraint. Finally, multi-connectivity and single connectivity with fast switching are examined as the means to combat the blockage. It is demonstrated that when switching to another gNB, the load should be considered together with the link quality.
On the one hand, this technology allows the deployment cost to be reduced. On the other hand, wireless backhaul raises multiple challenges. This includes the half-duplex constraint, which complicates the resource allocation procedure. In addition, the inherent properties of mmWave frequencies make a wireless connection more susceptible to blockage. Therefore, this study characterizes resource allocation, interference, and blockage avoidance techniques in the context of IAB networks.
The results of the research demonstrate that interference caused by mutual reception at the IAB node can be avoided using spatial diversity. The critical angular distance of more than 25 deg. is identified as the point at which mutual receptions start to influence each other. The dynamic resource allocation scheme is proposed, which enables load balancing in IAB networks limited by the half-duplex constraint. Finally, multi-connectivity and single connectivity with fast switching are examined as the means to combat the blockage. It is demonstrated that when switching to another gNB, the load should be considered together with the link quality.