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arXiv · 2603.11738

Dimensional Scaling Laws for Continuous Fluid Antenna Systems

Peter J. Smith·Amy S. Inwood·Michail Matthaiou·Rajitha Senanayake
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Abstract

Consider the signal-to-noise ratio (SNR) of a continuous fluid antenna system (CFAS) operating over a Rayleigh fading channel. In this paper, we extend traditional system assumptions and consider spatially coherent isotropic correlation, continuous positioning of the antenna rather than discrete, and the use of multi-dimensional space (1D, 2D and 3D). By focusing on the upper tail of the received SNR distribution (the high SNR probability (HSP)), we are able to derive asymptotically exact closed-form formulas for the HSP. Finally, these results lead to scaling laws which describe the increase in the HSP as we employ more dimensions and the optimal CFAS dimensions.

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Peter J. Smith, Amy S. Inwood, Michail Matthaiou, Rajitha Senanayake. 2026-03-12. Dimensional Scaling Laws for Continuous Fluid Antenna Systems. https://doi.org/10.1109/lwc.2025.3560861

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