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Search results for: ASYMMETRY, COMPLEMENTARY SPLIT-RING RESONATOR (CSRR), 5G, FREQUENCY LIMIT, HIGH FREQUENCY, MICROWAVE RESONATORS, PLANAR CIRCUITS.
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Design and Optimization of Metamaterial-based Highly-isolated MIMO Antenna with High Gain and Beam Tilting Ability for 5G Millimeter Wave Applications
PublicationThis paper presents a wideband multiple-input multiple-output (MIMO) antenna with high gain and isolation, as well as beam tilting capability, for 5G millimeter wave (MMW) applications. A single bow-tie antenna fed by a substrate-integrated waveguide (SIW) is proposed to cover the 28 GHz band (26.5–29.5 GHz) with a maximum gain of 6.35 dB. To enhance the gain, H-shaped metamaterial (MM)-based components are incorporated into the...
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Simulation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe aim of the research is investigation of the efficiency of weight averaging of pulse frequency modulated signal. It was shown that from the point of view of the reduction of the sampling error the best are polynomial weighing functions, for which the maximum of this component error decreases proportionally to the appropriate power of the number of...
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Design and Optimization of Metamaterial-Based 5G Millimeter Wave Antenna for Gain Enhancement
PublicationIn this brief, a low profile, broadband, high-gain antenna array based on optimized metamaterials (MMs) with dual-beam radiation is reported for 5G millimeters wave (mm-wave) applications. The design is a simple bow tie operating at a 5G band of 28 GHz. It consists of two bow ties with substrate integrated waveguide (SIW)-based power splitter. A broad impedance bandwidth of 26.3−29.8 GHz is obtained by appropriately combining the...
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A review of design approaches for the implementation of low-frequency noise measurement systems
PublicationElectronic noise has its roots in the fundamental physical interactions between matter and charged particles, carrying information about the phenomena that occur at the microscopic level. Therefore, Low-Frequency Noise Measurements (LFNM) are a well-established technique for the characterization of electron devices and materials and, compared to other techniques, they offer the advantage of being non-destructive and of providing...
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A new approach to active noise and vibration control - [Part I: the known frequency case]
PublicationThis paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time stable linear plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The disturbance rejection control rule is first derived and analyzed for a nominal plant model, different from...
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A new time-frequency detection method of stray current field interferenceon metal structures.
PublicationA new detection method has been presented of stray current field interference on underground metal structures. The method employs short time Fourier transformation (STFT). This method of analysis allows determination of signal spectral power density changes (e.g., structure potential) in the function of time. In the paper results have been presented of total time–frequency analysis of a pipeline potential in a stray current field...
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Modelowanie dokładności radiolokalizowania w różnych warunkach środowiskowych przy wykorzystaniu interfejsu radiowego 5G-NR
PublicationW artykule przedstawiono wyniki eksperymentalnych badań dokładności estymacji położenia terminala użytkownika korzystającego~z interfejsu radiowego 5G-NR. W środowisku miejskim dokonano rejestracji rzeczywistych sygnałów sieci 5G, a następnie przeprowadzono badania numeryczne. Celem było zweryfikowanie różnic dokładności estymacji położenia w trzech różnych środowiskach: wewnątrz- i zewnątrzbudynkowym oraz tzw. deep-indoor.
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Experimental investigation of the weight averaging of pulse frequency modulated sensor output signal
Open Research DataThe research aims to practically verify the results of theoretical analysis and simulations of the efficiency of weight averaging of pulse frequency modulated signal. For this purpose, a suitable test stand was built, and the control software in the LabVIEW environment was prepared. Then, a series of experiments were carried out to process and analyze...
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Włodzimierz Zieniutycz prof. dr hab. inż.
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Electromagnetic Simulation with 3D FEM for Design Automation in 5G Era
PublicationElectromagnetic simulation and electronic design automation (EDA) play an important role in the design of 5G antennas and radio chips. The simulation challenges include electromagnetic effects and long simulation time and this paper focuses on simulation software based on finite-element method (FEM). The state-of-the-art EDA software using novel computational techniques based on FEM can not only accelerate numerical analysis, but...
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Coupling of Blood Pressure and Subarachnoid Space Oscillations at Cardiac Frequency Evoked by Handgrip and Cold Tests: A Bispectral Analysis
PublicationThe aim of the study was to assess blood pressure–subarachnoid space (BP–SAS) width coupling properties using time–frequency bispectral analysis based on wavelet transforms during handgrip and cold tests. The experiments were performed on a group of 16 healthy subjects (F/M; 7/9) of the mean age 27.2 ± 6.8 years and body mass index of 23.8 ± 4.1 kg/m². The sequence of challenges was first handgrip and then cold test. The handgrip...
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Sample Rate Conversion Based on Frequency Response Masking Filter
PublicationThe sample rate conversion with high resampling ratios requires low-pass digital filters with very narrow transition band which results in high computational complexity and makes filter design problematic. Therefore in this work we propose to use the FRM method, which breaks the filter with a narrow transition band into a group of filters with reduced design requirements. These decreases the number of non-zero coefficients and...
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Mild poikilocapnic hypoxia increases very low frequency haemoglobin oxygenation oscillations in prefrontal cortex
PublicationBackground: The aim of the study was to investigate the effect of mild cerebral hypoxia on haemoglobin oxygenation(HbO2), cerebrospinal fluid dynamics and cardiovascular physiology. To achieve this goal, four signals were recorded simultaneously: blood pressure, heart rate / electrocardiogram, HbO2 from right hemisphere and changes of subarachnoid space (SAS) width from left hemisphere. Signals were registered from 30 healthy,...
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Intrinsic asymmetry with respect to adversary: a new feature of Bell inequalities
PublicationIt is known that the local bound of a Bell inequality is sensitive to the knowledge of the external observer about the settings statistics. Here we ask how that sensitivity depends on the structure of that knowledge. It turns out that in some cases it may happen that the local bound is much more sensitive to the adversaryʼs knowledge about the settings of one party than the other. Remarkably, there are Bell inequalities which are...
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Cost-Efficient Multi-Objective Design of Miniaturized Microwave Circuits Using Machine Learning and Artificial Neural Network
PublicationDesigning microwave components involves managing multiple objectives such as center frequencies, impedance matching, and size reduction for miniaturized structures. Traditional multi-objective optimization (MO) approaches heavily rely on computationally expensive population-based methods, especially when exe-cuted with full-wave electromagnetic (EM) analysis to guarantee reliability. This paper introduces a novel and cost-effective...
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Diagnostics of the tram track shape with the use of the global positioning satellite systems (GPS/Glonass) measurements with a 20 Hz frequency sampling
PublicationSatellite geodetic measurements used in the diagnosis of railway tracks require professional receivers and a very high frequency rate of data processing. It stems from a significant speed (10 km/h) kinematic measurements carried out during the passage of a measuring platform. The survey results (positions) of deformed railroad track have waveforms nature requiring additional processing methods and approximations. Due to the announcement...
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Rafał Lech dr hab. inż.
PeopleIEEE Senior Member #92122578 Rafal Lech was born in Elblag, Poland, in 1977. He received the M.Sc.E.E. and Ph.D. degrees (with honors) from the Gdansk University of Technology, Gdansk, Poland, in 2001 and 2007, respectively. He is currently with the Faculty of Electronics, Department of Microwave and Antenna Engineering, Telecommunications and Informatics, Gdansk University of Technology. His main research interests are electromagnetic-wave...
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Resonance Frequency Calculation of a Multilayer and Multipatch Spherical Microstrip Structure Using a Hybrid Technique
PublicationThis communication offers a rigorous analysis of the resonance frequency problem of a spherical microstrip structure mounted on a multilayer, dielectric-coated metallic sphere, with an electrically small radius. The structure consists of single or multiple metallic patches with arbitrary shapes. A full-wave analysis is employed with the use of proposed hybrid approach, combining the finite-difference technique with a spectral domain...
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Methods of measurement signal acquisition from the rotational flow meter for frequency analysis
PublicationOne of the simplest and commonly used instruments for measuring the flow of homogeneous substances is the rotational flow meter. The main part of such a device is a rotor (vane or screw) rotating at a speed which is the function of the fluid or gas flow rate. A pulse signal with a frequency proportional to the speed of the rotor is obtained at the sensor output. For measurements in dynamic conditions, a variable interval between...
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Diagnostics of the drive shaft bearing based on vibrations in the high-frequency range as a part of the vehicle's self-diagnostic system
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Joint time–frequency analysis of electrochemical noise
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Frequency bands selection of the Portevin–LeChatelier effect
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Continuous‐Frequency Method of Measurement of Electrode Impedance
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Multiple frequency tracker with improved tracking Capabilities
PublicationW pracy zaproponowano prostą modyfikację znanego z literatury wieloczęstotliwościowego adaptacyjnego filtra wycinającego, prowadzącą do istotnej poprawy jego charakterystyk nadążania.
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Relativistic runaway breakdown in low-frequency radio
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Low-frequency current noise in electrochromic devices
PublicationObserwowano szumy typu 1/f w elemencie wykazującym zjawisko elektrochromizmu - zmiany swoich parametrów optycznych (przezroczystości) pod wpływem przyłożonego napięcia. Element składał się z porowatej warstwy nanocząstek WO3 oraz tlenku Ni-V. Obserwowano gęstość widmową mocy prądu szumów, która zalezała liniowo od kwadratu prądu stałego I płynącego przez element. Stwierdzono, że intensywne przełączanie elementu między trybem przezroczystym...
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Modulation frequency constraints on wow and flutter determination
PublicationOpracowane wcześniej algorytmy do określania charakterystyki kołysania i drżenia dźwięku okazały się pomocne w rekonstrukcji rzeczywistych próbek dźwiękowych, jednakże przy ich opracowaniu nie określono przedziału częstotliwości modulujących, które mogą być przez nie śledzone. Prezentowany artykuł zawiera studium pozwalające wyznaczyć brakujące przedziały częstotliwości dla trzech algorytmów śledzących: przydźwięk sieciowy, pozostałość...
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Frequency characteristics of induction machine speed observers
PublicationWłaściwości napędu bezczujnikowego z silnikiem indukcyjnym zależą od struktury obserwatora prędkości. System ten wymaga starannej analizy w przypadku uszkodzenia maszyny, której celem jest odpowiedź na pytania: jak układ regulacji pracuje przy niesymetrii maszyny spowodowanej np. uszkodzeniem klatki wirnika oraz jak obserwator odtwarza pulsacje prędkości spowodowane niesymetrią maszyny. W artykule przedstawiono charakterystyki...
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Instantaneous complex frequency for pipeline pitch estimation
PublicationIn the paper a pipeline algorithm for estimating the pitch of speech signal is proposed. The algorithm uses instantaneous complex frequencies estimated for four waveforms obtained by filtering the original speech signal through four bandpass complex Hilbert filters. The imaginary parts of ICFs from each channel give four candidates for pitch estimates. The decision regarding the final estimate is made based on the real parts of...
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On the joint time-frequency characteristics of chemical oscillations
PublicationZaprezentowano rezultaty analizy czasowo-częstotliwościowej rejestrów potencjałowych oscylacyjnej reakcji Biełousowa-Żabotyńskiego (BŻ). Wybraną reprezentację czasowo-częstotliwościową w postaci algorytmu STFT zastosowano do analizy typowych przebiegów reakcji BŻ, prowadzonej w układzie zamkniętym. Zaprezentowano spektrogramy STFT ukazujące czasowo-częstotliwościową strukturę oscylacji regularnych, mieszanych i chaotycznych. Na...
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Wavelet analysis of frequency of air bubble departure
PublicationPrzedstawiono wyniki nieliniowej analizy częstotliwośći generowania pęcherzyków powietrza z dysz o średnicy 0.75 mm, 1.61 mm oraz 2.76 mm umieszczonych 15 cm poniżej poziomu wody.
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Optimization of the Vibrating Machines with Adjustable Frequency Characteristics
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Reconstruction of input signal of sensor with frequency output
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Continuous frequency method of measurement of electrode impedance.
PublicationPrzedstawione zostały matematyczne podstawy nowej metody pomiaru impedancji elektrodowej. Metoda wykorzystuje sygnał pobudzenia którego częstotliwość zmienia się liniowo w czasie. Amplituda sinusoidalnego niestacjonarnego pobudzenia jest stała. Zapis i analiza sygnału pobudzenia i odpowiedzi pozwalana wyznaczenie ciągłego widma impedancyjnego. Jednoczesna analiza czasowo częstotliwościowa wykonano została przy użyciu transformacji...
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The Low Frequency Noise Behaviour of SiC MESFETs
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A Model for Low Frequency Noise Generation in MOSFETs.
PublicationPrzedstawiono model generacji szumów małoczęstotliwosciowych tranzystora MOS. Model został użyty do symulacji szumów cienkotlenkowych tranzystorów MOS. Wyniki symulacji porównano z danymi pomiarowymi. Zaprezentowano sposób wykorzystania pomiarów szumów m.cz. do wyznaczania niektórych parametrów charakteryzujących tranzystory MOS.
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DLC coating in ring-on-ring sliding with water lubrication 10MPa/0.1m/s
Open Research DataWear tests in sliding friction of DLC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, DLC-W over DLC-W. Mean contact stress: 10MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: WATER. Tribometer: PT-3. Overall test time >15h. The test was augmented by vibration...
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DLC coating in ring-on-ring sliding with water lubrication 20MPa/0.1m/s
Open Research DataWear tests in sliding friction of DLC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, DLC-W over DLC-W. Mean contact stress: 20MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: WATER. Tribometer: PT-3. Overall test time >15h. The test was augmented by vibration...
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A Novel Modal Technique for Time and Frequency Domain Analysis of Waveguide Components
PublicationW pracy zaprezentowano, nową i szybką metodę analizy komponentów falowodowych. Metoda opiera się na kombinacji metody różnic skończonych, metody dekompozycji dziedziny obliczeniowej, redukcji rzędu modelu oraz dyskretnych rozwinięć funkcyjnych. Przedstawiona technika pozwala na skrócenie czasu analizy układu nawet o dwa rzędy wielkości w stosunku do poprzednich algorytmów.
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Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency
PublicationPial artery adjustments to changes in blood pressure (BP)may last only seconds in humans. Using a novelmethod called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of...
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Calculation of Resonance in Planar and Cylindrical Microstrip Structures Using a Hybrid Technique
PublicationA hybrid technique was employed for the analysis of the resonance frequency of thin planar and cylindrical microstrip structures with the patches of arbitrary geometry. The proposed technique utilizes a combination of Galerkin’s moment method and a finite-element method (FEM). In this approach, an FEM is adopted to calculate the patch surface current densities, and a method of moments is utilized to calculate the resonance frequencies...
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RSS-Based DoA Estimation Using ESPAR Antenna for V2X Applications in 802.11p Frequency Band
PublicationIn this paper, we have proposed direction-of arrival (DoA) estimation of incoming signals for V2X applications in 802. 11p frequency band, based on recording of received signal strength (RSS) at electronically steerable parasitic array radiator (ESPAR) antenna's output port. The motivation of the work was to prove that ESPAR antenna used to increase connectivity and security in V2X communication can be also used for DoA estimation....
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Krajowe laboratorium sieci i usług PL, 5G: kierunki badań i perspektywy rozwoju techniki 5G/6G
PublicationArtykuł przedstawia unikatową infrastrukturę badawczą PL 5G opracowaną w ramach projektu „ krajowe laboratorium sieci i usług 5G wraz z otoczeniem” oraz kierunki badań dotyczących techniki 5G oraz przyszłej sieci 6g. Laboratorium umożliwia prowadzenie praktycznych eksperymentów, w środowisku zbliżonym do warunków sieci operatorskiej, dotyczących rozwoju techniki 5G/6G, a także szerokiego spektrum jej zastosowań w środowiskach terenowych,...
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Time frequency representation of Doppler boold flow recordings
Open Research DataVital signals registration plays a grate role in biomedical engineering and education process. Well acquired data allow future engineers to observe certain physical phenomenons as well learn how to correctly process and interpret the data. This data set was designed for students to learn about Doppler phenomena and to demonstrate correctly and incorrectly...
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Low-Cost Surrogate Models for Microwave Filters
PublicationA novel low-cost kriging-based multivariable parametric macromodeling technique for microwave filters is presented. Kriging is used to model both the residues and poles of a microwave filter's reflection coefficient, and the zeros of the transmission coefficient. The proposed residue-pole-zero (RPZ) technique is demonstrated to efficiently model a high dimensional (8D) microwave filter with pseudoelliptic characteristics.
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Application of Complementary Signals in Built-In Self Testers for Mixed-Signal Embedded Electronic Systems
PublicationThis paper concerns the implementation of shape-designed complementary signals (CSs), matched to the frequency characteristic of the circuit under test, in built-in self testers (BISTs), dedicated to mixed-signal embedded electronic systems for testing their analog sections. The essence of the proposed method and solution of CS BIST is low-cost realization on the base of hardware and software resources of microcontrollers used...
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Standing Waves in One-Dimensional Resonator Contaning an Ideal Isothermal Gas Affected by the Constant Mass Force
PublicationThe study is devoted to standing acoustic waves in one-dimensional planar resonator which containing an ideal gas. A gas is affected by the constant mass force. Two types of physically justified boundary conditions are considered: zero velocity or zero excess pressure at both boundaries. The variety of nodal and antinodal points is determined. The conclusion is that the nodes of pressure and antinodes of velocity do not longer...
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Comparative Analysis of Developed Rainfall Intensity–Duration–Frequency Curves for Erbil with Other Iraqi Urban Areas
PublicationRainfall Intensity–Duration–Frequency (IDF) relationships are widely used in water infrastructure design and construction. IDF curves represent the relationship between rainfall intensity, duration, and frequency, and are obtained by analyzing observed data. These relationships are critical for the safe design of flood protection structures, storm sewers, culverts, bridges, etc. In this study, the IDF curves and empirical IDF formulas...
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System 5G - unifikacja radiokomunikacji
e-Learning CoursesProwadzący: dr hab. inż. Jarosław Sadowski, prof. PG i dr inż. Sławomir Gajewski Terminy realizacji: 18maja, 25 maja oraz 08 czerwca od godz. 09:00 do 14:00 Tematyka wykładu obejmuje podstawy funkcjonowania systemów radiokomunikacyjnych i telefonii komórkowej, obecny stan rozwoju telefonii na przykładzie LTE, oraz szerokie omówienie różnych aspektów sieci 5G: założenia, standard, właściwości medium transmisyjnego (problemy propagacji...
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An MOR Algorithm Based on the Immittance Zero and Pole Eigenvectors for Fast FEM Simulations of Two-Port Microwave Structures
PublicationThe aim of this article is to present a novel model-order reduction (MOR) algorithm for fast finite-element frequency-domain simulations of microwave two-port structures. The projection basis used to construct the reduced-order model (ROM) comprises two sets: singular vectors and regular vectors. The first set is composed of the eigenvectors associated with the poles of the finite-element method (FEM) state-space system, while...