Wyniki wyszukiwania - BazTech

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Fractal geometry applied to design of communications systems antennas

Krzysztofik W. J., Cao T. N.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2017

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nr 6

206--209, CD

EN

This paper presents the fractal geometries and their application in the design of small, multi-band antennas. Fractals are described by means of Iteration Function System. Some useful pre-fractals were designed, numerically modeled and fabricated for applications in different modern mobile communication systems such as GSM/UMTS, WLAN, GPS, TV-Sat, etc. Experimental verifications well confirmed the results of simulation made by means of HFSS computer code.

2

A New Implementation of UWB CRLH Based Antennas for Wireless Communications

Alibakhshi-Kenari M., Naser-Mogaddasi M.

Journal of Telecommunications and Information Technology

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2015

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nr 1

42--52

EN

In this article, a novel ultra wideband (UWB) small antennas based on the composite right/left-handed transmission lines structures are proposed. The antennas are pre- sented with best in size, bandwidth and radiation patterns. Their physical size and the operational frequency depend on the unit cell size and the equivalent transmission line model parameters of the CRLH-TL. To realize characteristics of frst proposed model, Q-shaped gaps printed into rectangular radiation patches are used. The antenna based on composite right/left-handed transmission lines is composed of two unit cells, each of which occupies only 10.8 x 8.6 mm and covers the 2.7{9.3 GHz bandwidth for VSWR < 2. The peak gain and radiation effciency, are 5.78 dBi and 42.1% 9.3 GHz, respectively. Moreover, the second designed antenna has the same size and enhancement bandwidth, gain and radiation effciency than the rst proposed antenna with similar design procedure. It is constructed of the printed Q-shaped four unit cells. The length, width and height are 21.6, 8.6 and 1.6 mm, respectively, and it covers 4.1{11.7 GHz bandwidth for VSWR < 2 having highest gain (7.18 dBi) and radiation effciency (92.69%) at 4.1 GHz.

3

Wielorezonansowe oraz szerokopasmowe anteny małych terminali

Kabacik P., Hossa R., Byndas A.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2005

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nr 1

18-23

PL

Przedstawiono zagadnienia anten przeznaczonych do pracy w wielosystemowych zminiaturyzowanych terminalach. Ze względu na wymagania praktycznych zastosowań uwagę poświęcono wielorezonansowym antenom i poszerzaniu ich pasm przy jednoczesnym dążeniu do możliwe najdalej idącej miniaturyzacji. Wskazano na zasadniczą zmianę roli ekranu w tego rodzaju antenach i uzasadniono, że bez dobrego zrozumienia rzeczywistej roli ekranu nie ma możliwości opracowania anten o szerokim paśmie pracy na jednej lub więcej rezonansach. Przedstawiono przykładowe wyniki naszego zespołu, w tym charakterystykę dopasowania anteny zajmującej 3 cm3 objętości i generującej dwa szerokie pasma.

EN

The paper presents major technical problems related to development of small antennas for use in multisystem miniature terminals. As multisystem applications imply use of multiresonance and wideband properties of terminal antennas, the primary attention is given to these two key issues. Furthermore, efficient bandwidth broadening techniques and antenna miniaturization methods are carefully considered. A substantial change of the ground plate rule has been pointed as a main novelty in small antennas. The authors believe that without a correct understanding of the actual rule of the ground, it is impossible to design wideband small antennas generating one or more resonance. Examples of results achieved under the research carried out by our team has been presented - among them an impedance characteristic for the miniature antenna (3 cm3) which generates two very broad bands.