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arXiv · 2304.00332

Characteristic Modes Analysis of Mutually Coupled Log-Periodic Dipole Antennas

Georgios Kyriakou·Pietro Bolli·Giuseppe Virone
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Abstract

Characteristic Modes Analysis (CMA) is a widely used method with recent progress in multi-antenna systems. We employ this method to characterize the mutual coupling phenomenon between two SKALA4.1 antennas, the low-frequency array elements of the future radiotelescope Square Kilometer Array (SKA-Low). The CMA accuracy is first validated at the lowest frequency range of interest with respect to a standard Method of Moments (MoM) solution by decomposing the single antenna into its characteristic modes. We then examine critical frequencies of a two-antenna system in modal decomposition, and characterize those responsible for the radiated electric field spurious spectral features owing to the mutual coupling. We connect these modes to first-order coupling of single antenna CMA modes, by using the eigenvalue data of both single- and two- antenna simulations.

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Georgios Kyriakou, Pietro Bolli, Giuseppe Virone. 2023-04-01. Characteristic Modes Analysis of Mutually Coupled Log-Periodic Dipole Antennas. https://doi.org/10.23919/eucap57121.2023.10133524

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