On Landau's Eigenvalue Theorem for Line-of-Sight MIMO Channels

Andrea Pizzo; Angel Lozano

doi:10.1109/lwc.2022.3208322.

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arXiv · 2210.05631

On Landau's Eigenvalue Theorem for Line-of-Sight MIMO Channels

Andrea Pizzo·Angel Lozano

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Abstract

An alternative derivation is provided for the degrees of freedom (DOF) formula on line-of-sight (LOS) channels via Landau's eigenvalue theorem for bandlimited signals. Compared to other approaches, Landau's theorem provides a general framework to compute the DOF in arbitrary environments, this framework is herein specialized to LOS propagation. The development shows how the spatially bandlimited nature of the channel relates to its geometry under the paraxial approximation that applies to most LOS settings of interest.

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Andrea Pizzo, Angel Lozano. 2022-10-11. On Landau's Eigenvalue Theorem for Line-of-Sight MIMO Channels. https://doi.org/10.1109/lwc.2022.3208322.

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