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Telecommunication industries and spectrum regulation authorities are increasingly interested in unlocking the 12 GHz band for two-way 5G terrestrial services. The 12 GHz band has a much larger bandwidth than the current sub-6 GHz band and better propagation characteristics than the millimeter wave (mmWave) band. Thus, the 12 GHz band offers great potential for improving the coverage and capacity of terrestrial 5G networks. However, interference issues between incumbent receivers and 5G radio links present a major challenge in the 12 GHz band. If one could exploit the dynamic contexts inherent to the 12 GHz band, one could reform spectrum sharing policy to create spectrum access opportunities for 5G mobile services. This article makes three contributions. First, it presents the characteristics and challenges of the 12 GHz band. Second, we explain the characteristics and requirements for spectrum sharing at a variety of levels to resolve those issues. Lastly, we present several research opportunities to enable harmonious coexistence of incumbent licensees and 5G networks within the 12 GHz band.
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SwarmShare: Mobility-Resilient Spectrum Sharing for Swarm UAV Networking in the 6 GHz Band
To mitigate the long-term spectrum crunch problem, the FCC recently opened up the 6 GHz frequency band for unlicensed use. However, the existing spectrum sharing strategies cannot support the operation of access points in moving vehicles such as cars and UAVs. This is primarily because of the directionality-based spectrum sharing among the incumbent systems in this band and the high mobility of the moving vehicles, which together make it challenging to control the cross-system interference. In this paper we propose SwarmShare, a mobility-resilient spectrum sharing framework for swarm UAV networking in the 6 GHz band. We first present a mathematical formulation of the SwarmShare problem, where the objective is to maximize the spectral efficiency of the UAV network by jointly controlling the flight and transmission power of the UAVs and their association with the ground users, under the interference constraints of the incumbent system. We find that there are no closed-form mathematical models that can be used characterize the statistical behaviors of the aggregate interference from the UAVs to the incumbent system. Then we propose a data-driven three-phase spectrum sharing approach, including Initial Power Enforcement, Offline-dataset Guided Online Power Adaptation, and Reinforcement Learning-based UAV Optimization. We validate the effectiveness of SwarmShare through an extensive simulation campaign. Results indicate that, based on SwarmShare, the aggregate interference from the UAVs to the incumbent system can be effectively controlled below the target level without requiring the real-time cross-system channel state information. The mobility resilience of SwarmShare is also validated in coexisting networks with no precise UAV location information.
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- Award ID(s):
- 2030157
- PAR ID:
- 10294460
- Date Published:
- Journal Name:
- 2021 18th Annual IEEE International Conference on Sensing, Communication, and Networking (SECON)
- Page Range / eLocation ID:
- 1 to 9
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SECON52354.2021.9491602
