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arXiv · 2103.16766

Cooperative Beam Hopping for Accurate Positioning in Ultra-Dense LEO Satellite Networks

Yu Wang·Ying Chen·Yunfei Qiao·Hejia Luo·Xiaolu Wang·Rong Li·Jun Wang
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Abstract

In ultra-dense LEO satellite networks, conventional communication-oriented beam pattern design cannot provide multiple favorable signals from different satellites simultaneously, and thus leads to poor positioning performance. To tackle this issue, in this paper, we propose a novel cooperative beam hopping (BH) framework to adaptively tune beam layouts suitable for multi-satellite coordinated positioning. On this basis, a joint user association, BH design and power allocation optimization problem is formulated to minimize average Cram\'er-Rao lower bound (CRLB). An efficient flexible BH control algorithm (FBHCA) is then proposed to solve the problem. Finally, a thorough experimental platform is built following the Third Generation Partnership Project (3GPP) defined non-terrestrial network (NTN) simulation parameters to validate the performance gain of the devised algorithm. The numerical results demonstrate that FBHCA can significantly improve CRLB performance over the benchmark scheme.

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Yu Wang, Ying Chen, Yunfei Qiao, Hejia Luo, Xiaolu Wang, Rong Li, Jun Wang. 2021-03-31. Cooperative Beam Hopping for Accurate Positioning in Ultra-Dense LEO Satellite Networks. https://arxiv.org/abs/2103.16766

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