Breaking the Degrees-of-Freedom Limit of Holographic MIMO Communications: A 3-D Antenna Array Topology
arXiv:2311.03004 · doi:10.1109/TVT.2024.3372704
Abstract
The performance of holographic multiple-input multiple-output (MIMO) communications, employing two-dimensional (2-D) planar antenna arrays, is typically compromised by finite degrees-of-freedom (DOF) stemming from limited array size. The DOF constraint becomes significant when the element spacing approaches approximately half a wavelength, thereby restricting the overall performance of MIMO systems. To break this inherent limitation, we propose a novel three-dimensional (3-D) antenna array that strategically explores the untapped vertical dimension. We investigate the performance of MIMO systems utilizing 3-D arrays across different multi-path scenarios, encompassing Rayleigh channels with varying angular spreads and the 3rd generation partnership project (3GPP) channels. We subsequently showcase the advantages of these 3-D arrays over their 2-D counterparts with the same aperture sizes. As a proof of concept, a practical dipole-based 3-D array, facilitated by an electromagnetic band-gap (EBG) reflecting surface, is conceived, constructed, and evaluated. The experimental results align closely with full-wave simulations, and channel simulations substantiate that the DOF and capacity constraints of traditional holographic MIMO systems can be surpassed by adopting such a 3-D array configuration.
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Cited by in corpus (5)
- Electromagnetic Modeling and Capacity Analysis of Rydberg Atom-Based MIMO System
- Electromagnetic Normalization of Channel Matrix for Holographic MIMO Communications
- Shadow Area and Degrees of Freedom for Free-Space Communication
- Optimal Dual-Polarized Planar Arrays for Massive Capacity Over Point-to-Point MIMO Channels
- Continuous Aperture Array (CAPA)-Based Multi-Group Multicast Communications