Temat: antenna arrays - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Side lobes reducing by variation of array apperture edge shape
Autorzy:: Gorobets, N.N.
Gorobets, Yu.N.
Kiyko, V.I.
Powiązania:: https://bibliotekanauki.pl/articles/308797.pdf
Data publikacji:: 2000
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: phone antenna arrays
side lobes level reducing
Opis:: A possibility of side lobes level reducing in plane antenna array by creation of aperture comb edge in arrays with rectangular and circular aperture shape together with usage of different types of reducing to the array edges amplitude distributions is investigated by computer analysis. It is shown that usage of the comb structure in combination with the reducing amplitude distribution enables one to reach the side lobes level reducing in the array to -27 ÷ -29 dB.
Źródło:: Journal of Telecommunications and Information Technology; 2000, 1-2; 85-89
1509-4553
1899-8852
Pojawia się w:: Journal of Telecommunications and Information Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Fuzzy Logic Based Intelligent Data Sensitive Security Model for Big Data in Healthcare
Autorzy:: Dubey, Somya
Verma, Dhanraj
Powiązania:: https://bibliotekanauki.pl/articles/2055246.pdf
Data publikacji:: 2022
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: microstrip patch
adaptive antennas
parabolic reflector
beamforming
antenna arrays
smart antenna
Opis:: An intelligent security model for the big data environment is presented in this paper. The proposed security framework is data sensitive in nature and the level of security offered is defined on the basis of the data secrecy standard. The application area preferred in this work is the healthcare sector where the amount of data generated through the digitization and aggregation of medical equipment’s readings and reports is huge. The handling and processing of this great amount of data has posed a serious challenge to the researchers. The analytical outcomes of the study of this data are further used for the advancement of the medical prognostics and diagnostics. Security and privacy of this data is also a very important aspect in healthcare sector and has been incorporated in the healthcare act of many countries. However, the security level implemented conventionally is of same level to the complete data which not a smart strategy considering the varying level of sensitivity of data. It is inefficient for the data of high sensitivity and redundant for the data of low sensitivity. An intelligent data sensitive security framework is therefore proposed in this paper which provides the security level best suited for the data of given sensitivity. Fuzzy logic decision making technique is used in this work to determine the security level for a respective sensitivity level. Various patient attributes are used to take the intelligent decision about the security level through fuzzy inference system. The effectiveness and the efficacy of the proposed work is verified through the experimental study.
Źródło:: International Journal of Electronics and Telecommunications; 2022, 68, 2; 245--250
2300-1933
Pojawia się w:: International Journal of Electronics and Telecommunications
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Hybrid adaptive beamforming approach for antenna array fed parabolic reflector for C-band applications
Autorzy:: Bawane, Sheetal
Kumar Panda, Debendra
Powiązania:: https://bibliotekanauki.pl/articles/27314230.pdf
Data publikacji:: 2023
Wydawca:: Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:: microstrip patch
adaptive antennas
parabolic reflector
beamforming
antenna arrays
smart antenna
Opis:: This paper presents the design of a parabolic reflector fed through a patch antenna array feed to enhance its directivity and radiation properties. Adaptive beam for‐ mers steer and alter an array’s beam pattern to increase signal reception and minimize interference. Weight selec‐ tion is a critical difficulty in achieving low SLL and beam width. Low Side Lobe Level [SLL]and narrow beam reduce antenna radiation and reception. Adjusting the weights reduces SLL and tilts the nulls. Adaptive beam formers are successful signal processors if their array output con‐ verges to the required signal. Smart antenna weights can be determined using any window function. Half Power Beam Width and SLL could be used to explore different algorithms. Both must be low for excellent smart antenna performance. In noisy settings, ACLMS and CLMS create narrow beams and side lobes. AANGD offers more control than CLMS and ACLMS. The blend of CLMS and ACLMS is more effective at signal convergence than CLMS and AANGD. It presents an alternative to the conventionally used horn‐based feed network for C‐band applications such as satellite communication. Broadside radiation patterns and 4x4 circular patch antenna arrays are used in the proposed design. 1400 aperture illumination is pro‐ vided by the array’s feed parabolic reflector, whose F/D ratio is 0.36. The proposed design’s efficacy is assessed using simulation analysis.
Źródło:: Journal of Automation Mobile Robotics and Intelligent Systems; 2023, 17, 1; 45--50
1897-8649
2080-2145
Pojawia się w:: Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Synthesizing Non-Uniformly Excited Antenna Arrays Using Tiled Subarray Blocks
Autorzy:: Mohammed, Jafar Ramadhan
Powiązania:: https://bibliotekanauki.pl/articles/27312954.pdf
Data publikacji:: 2023
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: antenna arrays
non-uniform amplitudes
performance optimization
tiled subarray blocks
Opis:: Conventionally, non-uniformly excited antenna arrays are synthesized by independently determining the excitation amplitude and phase of each single element. Such an approach is considered to be the most expensive and complex design method available. In this paper, the tilling technique is harnessed to synthesize non-uniformly excited antenna arrays. To apply this technique, the array elements are first divided into different subarray shapes, such as rectangles or squares known as tiles. The use of rectangular tile blocks instead of a single element architecture greatly simplifies the array design process and reduces array complexity. Next, the problem concerned with synthesizing sub-arrays comprising rectangular tile blocks is formulated and solved by using horizontal and vertical orientations of tiles having different shapes and sizes, and their larger integer expansions. The third approach to tiled design is a mixture of both previous tile architectures. A genetic algorithm is used to design such tiled arrays offering optimum sidelobe levels, beam width, directivity and taper efficiency. Simulation results demonstrated the effectiveness of the proposed tiled arrays.
Źródło:: Journal of Telecommunications and Information Technology; 2023, 4; 25--29
1509-4553
1899-8852
Pojawia się w:: Journal of Telecommunications and Information Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Reconfigurable Antenna Arrays with Phase-only Control in the Presence of Near-field Nulls
Autorzy:: Buttazzoni, G.
Vescovo, R.
Powiązania:: https://bibliotekanauki.pl/articles/308578.pdf
Data publikacji:: 2017
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: antenna arrays
near-ﬁeld nulls
phase-only control
power synthesis
reconfigurability
Opis:: In this paper an effective iterative method is presented for the power synthesis of reconfigurable antenna arrays. The algorithm is suitable for arrays of arbitrary geometry, including the case where a large number of elements is involved. The reconfigurability is achieved by phase-only control, so that the excitation amplitude of each array element remains constant during the reconfiguration process. Such amplitudes may be different from one array element to the others, and they are not assigned a priori, but are optimized. Furthermore, the electric field is imposed to vanish in a number of prescribed points of the near-field region, so that a strong field reduction is obtained in a neighborhood of them.
Źródło:: Journal of Telecommunications and Information Technology; 2017, 3; 88-93
1509-4553
1899-8852
Pojawia się w:: Journal of Telecommunications and Information Technology
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Reconfigurable Antennas: the State of the Art
Autorzy:: Yashchyshyn, Y.
Powiązania:: https://bibliotekanauki.pl/articles/226828.pdf
Data publikacji:: 2010
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: antenna arrays
reconfigurable antennas
semiconductor devices
MEMS switches
surface PIN diodes
Opis:: The paper provides an overview of the state of the art in the area of reconfigurable antennas. This emerging area has been rapidly developing in the recent years. This article brings a comprehensive summary of the high quality applied and fundamental research contributions in the above-mentioned field. A broad spectrum of topics is covered, reflecting the areas in which Institute of Radioelectronics's expertise is recognized worldwide.
Źródło:: International Journal of Electronics and Telecommunications; 2010, 56, 3; 319-326
2300-1933
Pojawia się w:: International Journal of Electronics and Telecommunications
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Zastosowanie szyków antenowych w lokalizacji źródeł wyładowań niezupełnych
Application of antenna arrays in the location of partial discharge sources
Autorzy:: Roehrich, J.
Szafraniak, B.
Zydroń, P.
Powiązania:: https://bibliotekanauki.pl/articles/267219.pdf
Data publikacji:: 2017
Wydawca:: Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:: wyładowania niezupełne
systemy lokalizacyjne
szyki antenowe
metody TOA/TDOA
partial discharges
locating system
antenna arrays
TOA/TDOA methods
Opis:: Wyładowania niezupełne (wnz) są źródłami impulsowych zaburzeń elektromagnetycznych o bardzo szerokim widmie. Dzięki temu dla ich wykrywania i lokalizowania mogą być stosowane metody antenowe, wykorzystujące różne techniki pomiarowe. W szczególności dotyczy to lokalizowania wyładowań powstających w liniach napowietrznych i urządzeniach stacji elektroenergetycznych wysokich i najwyższych napięć. W artykule przedstawiono podstawy i rozważania teoretyczne dotyczące zastosowania w tym celu szyków (macierzy) antenowych o różnych konfiguracjach oraz wybrane wyniki badań laboratoryjnych. Przedstawione zostały m.in. analizy zastosowania metody TDOA (Time Difference Of Arrival), pozwalającej na określenie położenia źródeł wyładowań niezupełnych w oparciu o pomiar różnic czasów detekcji przebiegów impulsowych rejestrowanych przez poszczególne anteny wchodzące w skład szyku antenowego.
Partial discharges (PD) are sources of very short impulsive electromagnetic disturbances with extra wide spectrum. As a result, aerial methods using various measuring techniques can be used to detect and locate them. In particular, this refers to locating partial discharges occurring at overhead transmission lines and power station equipment of high and very high voltages. The paper, which presents the continuation of the work of authors in this field, describes theoretical foundations and theoretical considerations as well as the results of laboratory investigations of the use of antenna arrays of various configurations for PDs source location. The analysis of the application of the TDOA method (Time Difference of Arrival) to determine the position of the discharge sources is based on the measurement of the time differences of pulse waveforms received by the individual antennas – members of particular antenna array.
Źródło:: Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2017, 57; 103-108
1425-5766
2353-1290
Pojawia się w:: Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:: Biblioteka Nauki

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