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Robust Beamforming Design for OTFS-NOMA

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 نشر من قبل Zhiguo Ding
 تاريخ النشر 2019
  مجال البحث الهندسة المعلوماتية
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 تأليف Zhiguo Ding




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This paper considers the design of beamforming for orthogonal time frequency space modulation assisted non-orthogonal multiple access (OTFS-NOMA) networks, in which a high-mobility user is sharing the spectrum with multiple low-mobility NOMA users. In particular, the beamforming design is formulated as an optimization problem whose objective is to maximize the low-mobility NOMA users data rates while guaranteeing that the high-mobility users targeted data rate can be met. Both the cases with and without channel state information errors are considered, where low-complexity solutions are developed by applying successive convex approximation and semidefinite relaxation. Simulation results are also provided to show that the use of the proposed beamforming schemes can yield a significant performance gain over random beamforming.



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