Q-factor and bandwidth of periodic antenna arrays over ground plane

Andrei Ludvig-Osipov; B. L. G. Jonsson

doi:10.1109/lawp.2019.2956420

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arXiv · 1909.08019

Q-factor and bandwidth of periodic antenna arrays over ground plane

Andrei Ludvig-Osipov·B. L. G. Jonsson

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Abstract

In this paper, the Q-factor expression for periodic arrays over a ground plane is determined in terms of the electric current density within the array's unit cell. The expression accounts for the exact shape of the array element. The Q-factor formula includes integration only over a volume of an element in a unit cell, and can thus be efficiently implemented numerically. The examples show good agreement between the proposed Q-factor, the full-wave-calculated tuned fractional bandwidth, and the input-impedance-based formula by Yaghjian and Best (2005) for the array of tilted dipoles and the loops array.

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Andrei Ludvig-Osipov, B. L. G. Jonsson. 2019-09-17. Q-factor and bandwidth of periodic antenna arrays over ground plane. https://doi.org/10.1109/lawp.2019.2956420

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