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arXiv · 2312.02839

Low-complexity Linear Multicast Beamforming for Cache-aided MIMO Communications

Mohammad NaseriTehrani·MohammadJavad Salehi·Antti Tölli
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Abstract

A practical and scalable multicast beamformer design in multi-input multi-output~(MIMO) coded caching~(CC) systems is introduced in this paper. The proposed approach allows multicast transmission to multiple groups with partially overlapping user sets using receiver dimensions to distinguish between different group-specific streams. Additionally, it provides flexibility in accommodating various parameter configurations of the MIMO-CC setup and overcomes practical limitations, such as the requirement to use successive interference cancellation~(SIC) at the receiver, while achieving the same degrees-of-freedom~(DoF). To evaluate the proposed scheme, we define the symmetric rate as the sum rate of the partially overlapping streams received per user, comprising a linear multistream multicast transmission vector and the linear minimum mean square error~(LMMSE) receiver. The resulting non-convex symmetric rate maximization problem is solved using alternative optimization and successive convex approximation~(SCA). Moreover, a fast iterative Lagrangian-based algorithm is developed, significantly reducing the computational overhead compared to previous designs. The effectiveness of our proposed method is demonstrated by extensive simulations.

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Mohammad NaseriTehrani, MohammadJavad Salehi, Antti Tölli. 2023-12-05. Low-complexity Linear Multicast Beamforming for Cache-aided MIMO Communications. https://arxiv.org/abs/2312.02839

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