paper 150305143407

Published: 2015-07-09

Concerning the Circular- and Square-loop Antennas Mounted over a Ground Plane of Finite Extent

Sulaiman Adeniyi Adekola,

Sulaiman Adeniyi Adekola

University of Lagos, Nigeria

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Ayotunde Abimbola Ayorinde,

Ayotunde Abimbola Ayorinde

University of Lagos, Nigeria

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Alex Ike Mowete

University of Lagos, Nigeria

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Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)1222-1227

Abstract

As a natural sequel to an earlier presentation [1], which compared the performance features of equal perimeter circular- and square-loop antennas located over finite ground planes, this paper, using the same formulation, examines the same performance characteristics, but this time, with the antennas being of equal cross-sectional areas; and with loop heights varying between 0.05λ and 1.00λ at the operating (center) frequency of 1.25 GHz. Computational results for the antennas’ input characteristics reveal that whereas they share virtually identical input resistance profiles, input reactance for the square loop has values that are in general, lower than those for the circular loop, for the entire range of ‘height above ground plane’ considered. Results for the E- and H-plane radiation field patterns indicate that when the loops are located at heights beyond 0.3λ above the finite ground plane, the front-lobes become distorted; an observation supported by the profiles of the forward directive gain, which display the ‘notch filter response’ behavior. Furthermore, the results suggest that acceptable front-to-back ratio performance can only be maintained if loop heights above the ground plane are kept below 0.3λ.

Citation

Sulaiman Adeniyi Adekola, Ayotunde Abimbola Ayorinde, and Alex Ike Mowete, "Concerning the Circular- and Square-loop Antennas Mounted over a Ground Plane of Finite Extent," Proceedings of 2015 Photonics & Electromagnetics Research Symposium, Prague, July 6 - 9，Page(s)1222-1227

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