This paper presents a design and measurement of symmetric bidirectional pattern antenna implemented by using a probe-fed open-ended rectangular waveguide (OERW) vertically attached with four-stacked-coupling-aperture (FSCA). For the OERW without FSCA, it provides asymmetric beam in forwards and backwards directions. With the effect of FSCA, that asymmetry is amended to be symmetry, and propagates the WLAN frequency band of 2.4–2.5 GHz with the return loss better than 10 dB, and maximum gain of 7.04 dBi. A prototype antenna was fabricated and measured. Obviously, the preliminary measured results are very reassuring, and reasonably in good agreement with simulation results.
Słowa kluczowe: Symmetrical beam antenna; Bidirectional antenna; Open-ended rectangular waveguide; Coupling aperture.
W artykule zaprezentowano projekt I badania symetrycznej, dwukierunkowej anteny wykorzystującej otwarty prostokątny falowód pionowo usytuowany z czterema sprzężonymi aperturami. Umożliwa ona asymetrię strumieni w przód i w tył. Antena obsługuje sieci WLAN o częstotliwości 2.4-2.5 GHz z maksymalnym wzmocnieniem 7.04 dB.
Keywords: antena dwukierunkowa, falowód, apertura
Point-to-point communication systems have promptly advanced and become one of the growing communication business over the late decades -. Particularly, point-topoint links between hosts and clients are required in numerous wireless communication systems over long distances, for examples, the microwave radio relay link, long length Wi-Fi, wireless WAN/LAN link, satellite communication, and home satellite television, etc. -. To increase the performance of the point-to-point communication desires a narrow-beam or pencil beam antenna with high gain , which is probably provided by a reflector antenna. To generate pencil beam for point-topoint communications, a symmetrical beam antenna is required for a primary feed , since the radiation pattern of the secondary antenna (reflector antenna) typically corresponds to that of the primary feed antenna . However, it is not easy to obtain symmetrical radiation pattern because of the asymmetrical beamwidth between the yz- and xz-planes depending on the antenna structure . The development of symmetrical beam antennas has been continuously researched and proceeded -. Among these symmetrical beam antenna designs, a tripleaperture waveguide antenna (TAWA) was lately introduced to be a primary feed antenna for reflector , because its structure is not complex. Nevertheless, the radiating section of TAWA is not small size. To further reduce the size of that radiating section, a probe-fed open-ended rectangular waveguide (OERW) with four-stacked-coupling-aperture (FSCA) antenna was preliminary studied for designing a symmetrical beam antenna in 2018 . It was found that the effect of FSCA could transform the asymmetrical beam to be symmetry at -3 dB beamwidth. However, an equal beamwidth of both yz- and xz-planes at -10 dB could not accomplish yet. Therefore, this paper aims to continuously improve the FSCA for the better symmetrical beamwidth at -10 dB b [...]
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