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arXiv · 2409.14958

A Cupola-Shaped Multimode Multiport Antenna for Aerial Direction Finding

Lukas Grundmann·Marc Gerlach·Wolfgang Schäfer·Dirk Manteuffel
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Abstract

A multimode multiport antenna (M$^3$PA), constisting of a single conducting structure, is proposed for use with the airborne collision avoidance system (ACAS). Its cupola-shaped surface is selected from a set of aerodynamically suitable and symmetric structures. The selection is based on a presented statistical evaluation procedure for direction-finding (DF) antennas and algorithms, which predicts the root mean square error (RMSE) of the estimation using characteristic modes (CMs). A demonstrator antenna and feed network is manufactured and its three ports are measured in an anechoic chamber. The results match the intended far-fields of an electric monopole and two magnetic dipoles. The presented flight test results show that the antenna is capable of unambiguous DF across the desired angular range in a real world environment.

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Lukas Grundmann, Marc Gerlach, Wolfgang Schäfer, Dirk Manteuffel. 2024-09-23. A Cupola-Shaped Multimode Multiport Antenna for Aerial Direction Finding. https://doi.org/10.1109/lawp.2024.3519709

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