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arXiv · 2304.03180

Exceptional Point Perspective of Periodic Leaky-Wave Antennas

Amar Al-Bassam·Dirk Heberling·Christophe Caloz
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Abstract

Over the past decade, the issue of gain degradation at broadside in periodic leaky-wave antennas (P-LWAs) has been resolved, using a circuit modeling approach, by introducing proper asymmetry in the unit cell of the antenna structure. This paper provides a more fundamental and insightful perspective of the problem by showing, using a simple coupled-mode analysis, that the optimal level of structural asymmetry corresponds to an exceptional point of the coupling parameter between the two eigenmodes of the P-LWA. This contribution represents a key step towards the development of a full electromagnetic resolution of the broadside issue.

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Amar Al-Bassam, Dirk Heberling, Christophe Caloz. 2023-03-06. Exceptional Point Perspective of Periodic Leaky-Wave Antennas. https://arxiv.org/abs/2304.03180

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