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arXiv · 2502.06980

Electromagnetic Channel Statistics for Continuous-Aperture Array (CAPA) Systems

Chongjun Ouyang·Boqun Zhao·Xingqi Zhang·Yuanwei Liu
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Abstract

The channel statistics of a continuous-aperture array (CAPA)-based channel are analyzed using its continuous electromagnetic (EM) properties. The received signal-to-noise ratio (SNR) is discussed under isotropic scattering conditions. Using Landau's theorem, the eigenvalues of the autocorrelation of the EM fading channel are shown to exhibit a step-like behavior. Building on this, closed-form expressions for the probability distribution of the SNR and the average channel capacity are derived. Numerical results are provided to validate the accuracy of the derivations.

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Chongjun Ouyang, Boqun Zhao, Xingqi Zhang, Yuanwei Liu. 2025-02-10. Electromagnetic Channel Statistics for Continuous-Aperture Array (CAPA) Systems. https://arxiv.org/abs/2502.06980

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