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Tytuł:
Ka Band-pass Filter Based on SIW Technology for Wireless Communications
Autorzy:
Damou, Mehdi
Benallou, Yassine
Chetioui, Mohammed
Boudkhil, Abdelhakim
Berber, Redouane
Powiązania:
https://bibliotekanauki.pl/articles/1839462.pdf
Data publikacji:
2021
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
coupling matrix
DGS
filters
Ka band
SIW
Opis:
The paper proposes a new third-order Chebyshev bandpass filter based on the substrate integrated waveguide (SIW) manufacturing technology using an inductive iris and a defected ground structure (DGS) station to resonate in the Ka frequency band, intended for wireless communication applications. All steps that are necessary for designing such a filter have been described in detail based on specific analytical equations harnessed to calculate the different synthesizable parameters of the proposed band-pass filter design, such as the coupling matrix, quality coefficients and initial geometric dimensions. The filter’s ideal frequency response is extracted from an equivalent circuit employing localized elements developed with the use of Design Microwave Office Software. Otherwise, HFSS is employed to set the initial parameters of the proposed topology that will not meet the target specifications defined previously. Accordingly, optimization procedures are necessary for different SIW band-pass filter parameters to reach a high frequency response for the proposed design. The detailed results presented show high efficiency of the SIW technology that offers good performance with lower filter volumes. Two topologies have been developed and then optimized to demonstrate the usefulness of EM software.
Źródło:
Journal of Telecommunications and Information Technology; 2021, 2; 49--56
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Curved-Pentagonal Planar Monopole Antenna for UHF Television Broadcast Receiving Antenna
Autorzy:
Yuwono, R.
Purnomowati, R. B.
Amri, M. Y.
Powiązania:
https://bibliotekanauki.pl/articles/958121.pdf
Data publikacji:
2016
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
planar monopole antenna
television broadcasting
UHF band
Opis:
A planar monopole antenna is an aerial, which the radiating element is perpendicular to the ground plane. It has five equal curvy sides and works at Ultra High Frequency (UHF) band of terrestrial broadcast 478–806 MHz. The curvy sides are made of five equal trimmed ellipses and separated 72o each ellipse to another, form pentagonal shape. Optimizations are obviously necessary to gain the antenna performance at the desired frequency range. The dimensions to optimize this antenna performance are the length of the sides, the offset of curvature, the antenna height from the ground plane, and the ground plane size. Optimization process is done by simulating the proposed antenna with calculated designs using Computer Simulation Technology (CST) Studio Suite 2015 software. The optimized antenna design then fabricated with a 75 W coaxial line fed, measured, and results: Voltage Standing Wave Ratio (VSWR) range of 1.05–1.28, antenna gain at 600 MHz is 15.33 dBi, elliptical polarized, and omnidirectional. With these features, this antenna should satisfy the requirements of UHF television broadcasting.
Źródło:
Journal of Telecommunications and Information Technology; 2016, 3; 103-107
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
History of Semiconductors
Autorzy:
Łukasiak, L.
Jakubowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/308134.pdf
Data publikacji:
2010
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
band theory
laser
Moore's law
semiconductors
transistor
Opis:
The history of semiconductors is presented beginning with the first documented observation of a semiconductor effect (Faraday), through the development of the first devices (point-contact rectifiers and transistors, early field-effect transistors) and the theory of semiconductors up to the contemporary devices (SOI and multigate devices).
Źródło:
Journal of Telecommunications and Information Technology; 2010, 1; 3-9
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recent advances in PBG structures
Autorzy:
Vorgul, I.Yu.
Marciniak, M.
Powiązania:
https://bibliotekanauki.pl/articles/308757.pdf
Data publikacji:
2000
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
photonic band gap
photonic crystals
optical communications
Opis:
We propose a review of word science achievements in the extremely extended for the recent few years field of photonic band gap structures The review concerns both theoretical and experimental investigations on PBG structures toward fabrication of the most optimal ones for different applications. The attention is given to the obtained results as well as to the used and developed methods.
Źródło:
Journal of Telecommunications and Information Technology; 2000, 1-2; 71-76
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dual-band Bisected Psi Antenna for 3G, Wi-Fi, WLAN and Wi-MAX Applications
Autorzy:
Sura, Penchala Reddy
Reddy, S. Narayana
Powiązania:
https://bibliotekanauki.pl/articles/308721.pdf
Data publikacji:
2020
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
3G
bisected psi
dual-band
stub
WLAN
Opis:
This paper presents an inexpensive and simple dual-band bisected psi antenna for 3G, Wi-Fi, WLAN, and WiMAX applications is presented. The antenna comprises a bisected psi-shaped patch on a low-price FR4 substrate with a cropped ground plane on the other side, and is fed by a 50 Ω microstrip line. It operates at two distinct frequency bands of 1.87–2.76 GHz and 5.16–5.75 GHz with |S11|≤ -10 dB.
Źródło:
Journal of Telecommunications and Information Technology; 2020, 1; 56-61
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Designing a Compact Microstrip Antenna Using the Machine Learning Approach
Autorzy:
Sharma, Kanhaiya
Pandey, Ganga Prasad
Powiązania:
https://bibliotekanauki.pl/articles/1839319.pdf
Data publikacji:
2020
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
artificial neural network
dual band
microstrip antenna
notch
Opis:
This paper presents how machine learning techniques may be applied in the process of designing a compact dual-band H-shaped rectangular microstrip antenna (RMSA) operating in 0.75–2.20 GHz and 3.0–3.44 GHz frequency ranges. In the design process, the same dimensions of upper and lower notches are incorporated, with the centered position right in the middle. Notch length and width are verified for investigating the antenna. An artificial neural network (ANN) model is developed from the simulated dataset, and is used for shape prediction. The same dataset is used to create a mathematical model as well. The predicted outcome is compared and it is determined that the model relying on ANN offers better results.
Źródło:
Journal of Telecommunications and Information Technology; 2020, 4; 44-52
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unsupervised Phoneme Segmentation Based on Main Energy Change for Arabic Speech
Autorzy:
Lachachi, N.
Powiązania:
https://bibliotekanauki.pl/articles/958116.pdf
Data publikacji:
2017
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
band frequencies
energy changes
formant analysis
phoneme segmentation
Opis:
In this paper, a new method for segmenting speech at the phoneme level is presented. For this purpose, author uses the short-time Fourier transform of the speech signal. The goal is to identify the locations of main energy changes in frequency over time, which can be described as phoneme boundaries. A frequency range analysis and search for energy changes in individual area is applied to obtain further precision to identify speech segments that carry out vowel and consonant segment confined in small number of narrow spectral areas. This method merely utilizes the power spectrum of the signal for segmentation. There is no need for any adaptation of the parameters or training for different speakers in advance. In addition, no transcript information, neither any prior linguistic knowledge about the phonemes is needed, or voiced/unvoiced decision making is required. Segmentation results with proposed method have been compared with a manual segmentation, and compared with three same kinds of segmentation methods. These results show that 81% of the boundaries are successfully identified. This research aims to improve the acoustic parameters for all the processing systems of the Arab speech.
Źródło:
Journal of Telecommunications and Information Technology; 2017, 1; 12-20
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of a Split Circle Element for Microstrip Reflectarrays
Autorzy:
Sayidmarie, Khalil H.
Yahya, Likaa S.
Powiązania:
https://bibliotekanauki.pl/articles/24200749.pdf
Data publikacji:
2023
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
microstrip antenna
reflectarray antenna
split circular
X band
Opis:
A split circular element is proposed as a unit cell for reflectarray antennas. The unit cell is derived from a circle divided into four equal sectors. The radius of two oppositely located sectors is then scaled by a certain factor to form the proposed shape. The CST Microwave Studio Suite software simulator was used to investigate the performance of the proposed unit cell, which was evaluated using Floquet port excitation. The designed element's reflection phase range was compared to that of a conventional circular patch. Four scenarios of varied substrate characteristics are investigated for the antenna to establish the best performance parameters. The simulations showed that a basic substrate with a thickness of 0.16 mm and a dielectric constant of 3.2, backed by a 3 mm foam with a dielectric constant of 1.05 and a scaling factor of 0.72 offers a wide phase range of 601.3°. The obtained phase slope is 76.37°/mm or 134°/GHz.
Źródło:
Journal of Telecommunications and Information Technology; 2023, 3; 62--67
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
High-field current transport and charge trapping in buried oxide of SOI materials under high-field electron injection
Autorzy:
Nazarov, A.N.
Houk, Y.
Kilchytska, V.I.
Powiązania:
https://bibliotekanauki.pl/articles/308027.pdf
Data publikacji:
2004
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
Fowler-Nordheim current
trap-assisted tunneling
silicon-on-insulator
buried oxide
SIMOX
UNIBOND
anode hole injection
band-to-band impact ionization
Opis:
Mechanisms of the charge transfer, the charge trapping, and the generation of positive charge during the high-field electron injection into buried oxide of silicon-on-insulator structures fabricated by different technologies are analyzed based on the data obtained from current-voltage, injection current-time, and capacitance-voltage characteristics together with SIMS data. Electron injection both from the Si film and the Si substrate is considered. The possibility of using the trap-assisted electron tunneling mechanisms to explain the high-field charge transfer through the buried oxides of UNIBOND and SIMOX SOI materials is considered. It is shown that considerable positive charge is accumulated near the buried oxide/substrate interface independently from the direction of the injection (from the film or from the silicon substrate) for UNIBOND and SIMOX SOI structures. Thermal stability of the charge trapped in the buried oxides is studied at temperatures ranging from 20 to 400° C. The theory is compared with the experimental data to find out the mechanisms of the generation of positive charge in UNIBOND and SIMOX buried oxides.
Źródło:
Journal of Telecommunications and Information Technology; 2004, 1; 50-61
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A CPW-fed Sigma-shaped MIMO Antenna for Ka Band and 5G Communication Applications
Autorzy:
Madhav, B. T. P.
Devi, G. J.
Lakshman, P.
Anilkumar, T.
Powiązania:
https://bibliotekanauki.pl/articles/309564.pdf
Data publikacji:
2018
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
5G
coplanar waveguide
Ka band
MIMO
satellite downlink
Opis:
This article presents a MIMO compact antenna measuring 45×45×1.6 mm, on the FR4 substrate, proposed for Ka band and 5G communication applications. The proposed design is suitable to overcome the issues connected with massive MIMO. It has four-sigma-shaped radiating elements and a c-shaped ground plane with coplanar waveguide feeding. Its compact dimensions suit it for most existing communications systems. The aerial operates in the 21–30 GHz range, which covers Ka and 5G communication bands. The proposed antenna exhibits the average efficiency of more than 76% within its operating band and gives a minimum signal to noise plus interference ratio. The presented antenna covers several services, such as Ka band satellite downlink applications and future 5G communication applications.
Źródło:
Journal of Telecommunications and Information Technology; 2018, 4; 97-106
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Dual-band Circularly-polarized Printed Monopole Antenna for Wi-Fi and WiMAX Applications
Autorzy:
Lwin, Zaw Myo
Aye, Thae Su
Powiązania:
https://bibliotekanauki.pl/articles/307652.pdf
Data publikacji:
2019
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
circular polarization
dual-band antenna
printed monopole antenna
rectangular slit
Opis:
This paper presents a rectangular-shaped printed monopole antenna with circular polarization for Wi-Fi (2.4–2.484 GHz) and WiMAX (3.3-3.7 GHz) bands. The antenna relies on asymmetric arrangement of the patch with respect to the microstrip feed, in order to generate circular polarization. Dual-band (Wi-Fi and WiMAX) operation is enabled by inserting a slit in the corner of the ground plane. Simulation results show a bandwidth increase of 15.9% (2.2–2.58 GHz) for Wi-Fi, and of 24.16% (3.13–3.99 GHz) for WiMAX applications. Furthermore, beamwidths at the axial ratio of 3 dB equal 48˚ and 51˚ for the x-z plane and y-z planes, respectively.
Źródło:
Journal of Telecommunications and Information Technology; 2019, 4; 50-54
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dual-band multi slot patch antenna for wireless applications
Autorzy:
Samsuzzaman, M.
Islam, M.T.
Faruque, M. R. I.
Powiązania:
https://bibliotekanauki.pl/articles/307982.pdf
Data publikacji:
2013
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
Ku/K band
microstrip patch antenna
multiband
satellite
slotted
triangular
Opis:
In this paper a novel configuration of broadband multi slot antenna for C/X bands is presented and analyzed. By cutting two diamond slots in the middle of the rectangular patch and three triangular slots in the right side of the patch, resonances can be created. Microstrip feed line is used in the down side region of the patch. Antenna characteristics were simulated using a finite element method (HFSS). According to simulations, the proposed multiple slot antennas can provide two separated impedance bandwidths of 970 MHz (about 11.96% centred at 8.11 GHz band) and 890 MHz (about 9.76% centred at 9.42 GHz band) and stable radiation patterns, promising for satellite systems.
Źródło:
Journal of Telecommunications and Information Technology; 2013, 2; 19-23
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photonic band gaps in complex layered arrays
Autorzy:
Prosvirnin, S.L.
Tretyakov, S.A.
Vasilyeva, T.D.
Fourrier-Lamer, A.
Zouhdi, S.
Powiązania:
https://bibliotekanauki.pl/articles/309146.pdf
Data publikacji:
2001
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
photonic band gap structures
double-periodic arrays
reflective and transmitting properties
Opis:
Reflective and transmitting properties of several layers of double-periodic arrays are studied. In the arrays, elements are conducting inclusions of various shapes. It is shown that in tbese structures all the phenomena recently found in dense wire grids with periodical defects (so-called photonic band gap structures) can be observed and explained in simple terms of inter-layer and inclusion resonances. Frequency-selective (with two and more stop bands) and polarization transformation properties of these arrays are demonstrated.
Źródło:
Journal of Telecommunications and Information Technology; 2001, 4; 48-51
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Critical modeling issues of SiGe semiconductor devices
Autorzy:
Palankovski, V.
Selberherr, S.
Powiązania:
https://bibliotekanauki.pl/articles/308035.pdf
Data publikacji:
2004
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
SiGe HBT
numerical simulation
band gap
mobility
small-signal simulation
S-parameters
Opis:
We present the state-of-the-art in simulation of silicon-germanium (SiGe) semiconductor devices. The work includes a detailed comparison of device simulators and current transport models. Among the critical modeling issues addressed in the paper, special attention is focused on the description of the anisotropic majority/minority electron mobility in strained SiGe grown on Si. We use a direct approach to obtain scattering parameters (S-parameters) and other derived figures of merit of SiGe heterojunction bipolar transistors (HBTs) by means of small-signal AC-analysis. Results from two-dimensional hydrodynamic simulations of SiGe HBTs are presented in good agreement with measured data. The examples are chosen to demonstrate technologically important issues which can be addressed and solved by device simulation.
Źródło:
Journal of Telecommunications and Information Technology; 2004, 1; 15-25
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rectangular Dielectric Resonator Antenna with Single Band Rejection Characteristics
Autorzy:
Debab, Mohamed
Mahdjoub, Zoubir
Powiązania:
https://bibliotekanauki.pl/articles/958120.pdf
Data publikacji:
2019
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
band-stop function
C-shaped slot
dielectric resonator antenna (DRA)
planar monopole
Opis:
In this paper, a rectangular dielectric resonator antenna (DRA) suitable for wideband applications is presented and a band notch of WLAN (5.15–5.75) GHz is proposed. The DRA is mainly composed of a 20 × 20 mm rectangular dielectric resonator, coated with metal on the top surface, and a circular monopole excitation patch with an air gap insert. A coaxial line feed is used to excite the circular, planar monopole. An open-ended quarter wavelength C-shaped slot is embedded in the circular patch to create the notched band. The simulated results demonstrate that the proposed design produces an impedance bandwidth of more than 80%, ranging from 3.10 to 7.25 GHz for a reflection coefficient of less than −10 dB and with a band rejection at 5.50 GHz. Band notch characteristics, VSWR, and radiation patterns are studied using the HFSS high-frequency simulator and CST Studio software.
Źródło:
Journal of Telecommunications and Information Technology; 2019, 1; 76-82
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł

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