Temat: ultra-wideband (UWB) - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Optical generation of ultra-wideband signals with a reconfigurable spectral notch-band
Autorzy:: Xiang, P.
Chen, Y.
Chen, D.
Zhao, J.
Powiązania:: https://bibliotekanauki.pl/articles/174353.pdf
Data publikacji:: 2014
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: ultra-wideband (UWB)
ultra-wideband over fiber
notch-band
interference avoidance
Opis:: A novel method for optical generation of ultra-wideband signals with a reconfigurable spectral notch-band is proposed. In the proposed system, ultra-wideband signals are generated in the optical domain and an optical tunable delay line is deployed to introduce a notch-band to the spectral profile of the generated ultra-wideband signals, which can effectively avoid the signal interference between ultra-wideband signals and pre-planned narrowband wireless signals used in wireless local area networks (WLAN). A theoretical model describing the proposed system is derived; the optical generation and fiber transmission of ultra-wideband signals with a reconfigurable notch-band are demonstrated via computer simulations.
Źródło:: Optica Applicata; 2014, 44, 3; 411-419
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Polarity-reversed ultra-wideband monocycle pulse generation with dual-channel multicasting in a photonic crystal fiber
Autorzy:: Gong, J
Hui, Z
Powiązania:: https://bibliotekanauki.pl/articles/173791.pdf
Data publikacji:: 2015
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: nonlinear optics
cross-phase modulation (XPM)
radio frequency photonics
ultra-wideband (UWB)
photonic crystal fiber (PCF)
Opis:: This paper proposes and demonstrates a novel scheme of a two-channel-output ultra-wideband monocycle pulse generator consisting of a 100 m dispersion-flattened highly nonlinear photonic crystal fiber and two optical bandpass filters. Based on the cross-phase modulation effect in a dispersion-flattened highly nonlinear photonic crystal fiber, two polarity-reversed ultra-wideband monocycle pulses simultaneously output from two different channels are successfully achieved by appropriately locating the probe wavelength at the left linear slope and the right linear slope of the two optical bandpass filters transmission spectra, respectively. The full width at half-maximum and a fractional bandwidth of 24 ps and 260% for a positive pulse, 24 ps and 251% for a negative pulse are obtained. Moreover, the influences of input signal powers, the polarization misalignment between the data light and the continuous wave probe light, and probe wavelength variation on the double output ultra-wideband signals quality are also investigated. The results show that the system has some tolerance to both the input signal power fluctuation and the slight polarization mismatch and even can efficiently operate with a widely tunable wavelength range. This makes it very attractive for engineering applications in future multiuser ultra-wideband-over-fiber communication systems.
Źródło:: Optica Applicata; 2015, 45, 1; 25-39
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Converged ultra-wideband and multi-level wired signal downstream transport over single wavelength in wavelength-division multiplexing passive optical network
Autorzy:: Ma, H
Wang, F.
Wang, W.
Zhang, X
Yu, Q.
Powiązania:: https://bibliotekanauki.pl/articles/174929.pdf
Data publikacji:: 2015
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: ultra-wideband (UWB)
multi-level amplitude switch keying (M-ASK)
wavelength-division multiplexing passive optical network (WDM-PON)
Opis:: Simultaneous providing services of ultra-wideband and wired signal over single wavelength can greatly decrease the complexity and reduce the costs of a wavelength-division multiplexing passive optical network. However, ultra-wideband signal occupies the spectrum range from 3.1 to 10.6 GHz, and a narrow idle frequency band (from 0 to 3.1 GHz) could be employed to transport wired signal with a limited rate. In this paper, we proposed a scheme to simultaneously provide ultra-wideband and wired services, in which the information rate of the wired signal is enhanced by employing a multi-level amplitude switch keying signal in the idle frequency band formed by ultra-wideband signal. In comparison with other advanced modulation formats used for wavelength-division multiplexing passive optical networks such as orthogonal frequency division multiplexing, multi-level amplitude switch keying signal can be easily received by using intensity modulation direct detection, which will greatly reduce the cost of end-users. Especially, if a multi-band ultra-wideband signal is substituted for the direct-sequence ultra-wideband signal, the available spectrum range to transport wired signal will be easily extended to 5 GHz as multi-band ultra-wideband signal has a narrower spectrum width and flexible center frequency, so 4-amplitude switch keying signal with a rate of 5 Gbaud will achieve an information rate of 10 Gbit/s.
Źródło:: Optica Applicata; 2015, 45, 4; 433-445
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Synthesis of Binary Group-Complementary Sequences
Autorzy:: Koshevyy, V.M.
Powiązania:: https://bibliotekanauki.pl/articles/116221.pdf
Data publikacji:: 2018
Wydawca:: Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:: ultra wideband (UWB)
binary sequences
binary group-complementary sequences
complementary sequences
reduction of the number sequences
set of sequences
synthetized sequences
radar signals
Opis:: Algorithm of binary {-1, 1} group-complementary sequences direct construction for any sequences length N is suggested. On the base of these sequences the signals with very wide frequency bandwidth may be constructed (up to the ultra wideband (UWB) signals). Synthesized sequences may found their application in radar and communication.
Źródło:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2018, 12, 3; 545-548
2083-6473
2083-6481
Pojawia się w:: TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Characterization of an aperture-stacked patch antenna for ultra-wideband wearable radio systems
Autorzy:: Klemm, M.
Troester, G.
Powiązania:: https://bibliotekanauki.pl/articles/307769.pdf
Data publikacji:: 2005
Wydawca:: Instytut Łączności - Państwowy Instytut Badawczy
Tematy:: ultra-wideband
UWB
ultra-wideband antennas
ultra-wideband communication
Opis:: This paper presents, for the first time, the time-domain characteristics of an aperture-stacked patch antenna (ASPA) for ultra-wideband (UWB) wearable devices. The methodology of antennas characterization for UWB radio systems is also outlined. The antenna operates within the 3-6 GHz frequency band. Time- and frequency-domain characteristics of this antenna are presented in transmission mode (Tx), receiving mode (Rx) and for 2-antenna (Tx-Rx) system. The pulse driving the antenna has duration of 0.65 ns. In the Tx mode, pulses radiated in different directions of the H-plane have very similar shapes. Fidelity factors are as high as 91.6-99.9%. For 2-antenna system, pulses received in normal and end-fire-like directions have the fidelity of 69.5%. As it was found, antenna does not behave "reciprocal" comparing Tx and Rx modes. For normal propagation direction, radiated pulse is the 2nd derivative of the input waveform, but in the Rx mode, received pulse is the 1st derivative of the incident plane wave. This antenna can be used for transmission of short-pulses, even 0.65-1 ns in duration. It is also small (patch planar dimensions 32/19 mm) and compact. Microstrip configuration allows further integration of active devices on the same board. Taking into account above results we can say that ASPA is a good candidate for UWB non-invasive wireless body area network (WBAN) applications.
Źródło:: Journal of Telecommunications and Information Technology; 2005, 2; 39-44
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:: The Positioning Accuracy Based on the UWB Technology for an Object on Circular Trajectory
Autorzy:: Grzechca, D.
Hanzel, K.
Powiązania:: https://bibliotekanauki.pl/articles/227286.pdf
Data publikacji:: 2018
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: Ultra-Wideband
UWB
localization
propellers positioning
trilateration
location filtration
Opis:: This paper presents the comparison of filtering methods – median filtration, moving average Kalman filtration and filtration based on a distance difference to determine the most accurate arm length for circular motion, as a model of wind turbine propellers movement. The experiments have been performed with the UWB technology system containing four anchors and a tag attached to 90 cm arm that was rotated with speed up to 15.5 rad/s (as a linear speed of 50 km/h). The trilateration concept based on the signal latency has been described in order to determinate the position of an object on circular trajectory. The main objective is the circle plane rotation (parallel and perpendicular) with respect to the anchors plane reference system. All research tasks have been performed for various cases of motion schemes in order to get the filtration method for object in motion under best accuracy goal. Filtration methods have been applied on one of two stages of the positioning algorithm: (1) on raw data got from the single anchor-tag (before trilateration); (2) on the position obtained from four anchors and tag (after trilateration). It has been proven that the appropriate filtering allows for higher location accuracy. Moreover, location capabilities with the use of UWB technology – shows prospective use of positioning of objects without access to other positioning forms (ex. GPS) in many aspects of life such as currently developing renewable, green energy sources like wind turbines where the circular motion plays an important role, and precise positioning of propellers is a key element in monitoring the work of the whole wind turbine.
Źródło:: International Journal of Electronics and Telecommunications; 2018, 64, 4; 487-494
2300-1933
Pojawia się w:: International Journal of Electronics and Telecommunications
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Research on a scheme of generating ultra-wideband doublet signal based on the cross-gain modulation in a semiconductor optical amplifier
Autorzy:: Zhang, K.
Shao, J.
Powiązania:: https://bibliotekanauki.pl/articles/173646.pdf
Data publikacji:: 2018
Wydawca:: Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:: ultra-wideband
UWB
semiconductor optical amplifier
SOA
cross-gain modulation
XGM
Opis:: We propose a novel scheme for generating ultra-wideband doublet signal based on the cross-gain modulation effect in a semiconductor optical amplifier. This scheme requires only a semiconductor optical amplifier and an optical source. By using OptiSystem software, we simulate and analyze the effect of the input signal light power and wavelength, the pulse width and injection current on the generated doublet pulse. In addition, the optimal range of parameters are also given in the simulation process.
Źródło:: Optica Applicata; 2018, 48, 1; 127-135
0078-5466
1899-7015
Pojawia się w:: Optica Applicata
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: Matrix Analysis and Pulse Transmission of Antenna Array for MIMO UWB Systems
Autorzy:: Czawka, G.
Garbaruk, M.
Powiązania:: https://bibliotekanauki.pl/articles/226514.pdf
Data publikacji:: 2011
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: planar UWB antennas
computer-aided design
ultra-wideband communication
MIMO system
Opis:: This paper presents a theoretical matrix analysis of antenna structure consisting of two double-element planar antennas for ultra-wideband (UWB) application in 2*2 MIMO indoor communication systems. The structure and characteristics of planar two-element UWB antenna are presented. Two matrix models of MIMO antenna system are represented in the paper. A standard MIMO signal transmission matrix without taking into consideration the coupling between antennas is described. A new approach to a full electromagnetic analysis based on the scattering matrix of the MIMO spatial antenna array is proposed. Functional power parameters for the whole MIMO UWB transmit-receive antenna structure are introduced. Results of computer simulations of different matrices describing a MIMO antenna system and the transmission propagation pulses are presented.
Źródło:: International Journal of Electronics and Telecommunications; 2011, 57, 1; 91-96
2300-1933
Pojawia się w:: International Journal of Electronics and Telecommunications
Dostawca treści:: Biblioteka Nauki

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