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Search results for: ANTENY LCR
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Alms-panel of Anton Moeller in St. Mary's Church in Gdańsk
Open Research DataThe data set concerns epigraphy. It refers to the Alms-panel placed in St. Mary’s Church in Gdańsk, that is the work of Gdańsk painter Antoni Moller, made in 1607, or rather – to be more specific – to lower part of this work, which are the verses from Holy Bible. Data set contains one general photo of the inscription, transcription of its text in Latin...
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The role of tungsten in formation of active sites for no SCR on the V-W-O catalyst surface — quantum chemical modeling (DFT)
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PCR Melting Profile method for genotyping analysis of vancomycin-resistant Enterococcus faecium isolates from Hematological Unit patients
PublicationW ostatnich latach znacząco wzrasta liczba szczepów Enterococcus opornych na wankomycynę. Stwarzają one problemy medyczne u pacjentów skolonizowanych czy zainfekowanych tymi drobnoustrojami. W przedstawionych badaniach, określiliśmy genetyczne podobieństwo pomiędzy izolatami E. faecium VRE, pozyskiwanymi w okresie od kwietnia 2003 do kwietnia 2005 od pojedynczych pacjentów oddziału Hematologicznego Specjalistycznego Publicznego...
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Long-working-distance Raman system for monitoring of uPA ECR CVD process of thin diamond/DLC layers growth
PublicationW artykule przedstawiono konstrucję systemu optoelektronicznego do monitoringu ramanowskiego in-situ procesu μPA ECR CVD (ang.: Microwave Plasma Assisted Electron Cyclotron Resonance Chemical Vapour Deposition), stosowanego do osadzania cienkich warstw diamentowych i diamentopodobnych DLC. System ma budowę modułową i wyposażony jest w dedykowane sondy optyczne. Przedstawiono wyniki pomiarów testowych, potwierdzjące, że system posiada...
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Usefulness of PCR Melting Profile Method for Genotyping Analysis of Klebsiella oxytoca Isolates from Patients of a Single Hospital Unit
PublicationOpracowanie szybkich i prostych metod typowania jest wymagane w celu identyfikacji potencjalnych źródeł zakażenia ludzi drobnoustrojami oportunistycznymi. Klebsiella spp. należą do grupy bakterii oportunistycznych odpowiedzialnych za wzrost liczby wieloopornych zakażeń szpitalnych. Ostatnio pokazaliśmy wysoką różnorodność genetyczną K. oxytoca używając dużej kolekcji szczepów izolowanych przez 50 lat od pacjentów z kilku szpitali...
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Fusion of DNA-binding domain of Pyrococcus furiosus ligase with TaqStoffel DNA polymerase as a useful tool in PCR with difficult targets
PublicationThe DNA coding sequence of TaqStoffel polymer- ase was fused with the DNA-binding domain of Pyrococcus furiosus ligase. The resulting novel recombinant gene was cloned and expressed in E. coli. The recombinant enzyme was purified and its enzymatic features were studied. The fusion protein (PfuDBDlig-TaqS) was found to have enhanced processivity as a result of the conversion of the Taq DNA polymerase from a relatively low processive...
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Spatial characterization of H 2: CH 4 dissociation level in microwave ECR plasma source by fibre-optic OES
PublicationSpatially resolved optical emission spectroscopy (SR-OES) was used to investigate microwave activated H2/Ar/CH4 plasma under conditions of the electron cyclotron resonance (ECR). The chemistry and composition of the gas phase were studied using self-designed fibre-optic system with echelle type spectrometer during CVD deposition of polycrystalline diamond. One-dimensional intensity profiles of the main species were collected along...
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Zaawansowany system analizy kolorowych obrazów otrzymywanych metodą LCT podczas modelowania efuzyjnego chłodzenia łopatek turbin gazowych
PublicationArtykuł zawiera koncepcję oraz projekt zaawansowanego systemu analizy obrazów LCT w badaniach stanów nieustalonych, przydatnych przy optymalizacji geometrii różnego rodzaju aparatów i urządzeń przemysłowych. Proponowany system oparty będzie o autorskie rozwiązanie programistyczne do zbierania i analizy danych (przede wszystkim kolorowych obrazów) w czasie rzeczywistym. Koncepcja układu pomiarowego zostanie wykorzystana w badaniach...
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A brief note on entire fracture surface topography parameters for 18Ni300 maraging steel produced by LB-PBF after LCF
PublicationThe concept of entire fracture surface investigation is helpful in explaining fatigue phenomena. In this paper, this method has been applied for 18Ni300 maraging steel using a 3D measurement system. Before post-mortem analysis, the specimens produced by laser beam powder bed fusion (LB-PBF) were tested under low-cycle fatigue (LCF) for eight strain amplitudes in the interval 0.3% to 1.0%. The attention was placed on the relationship...
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Strain energy density and entire fracture surface parameters relationship for LCF life prediction of additively manufactured 18Ni300 steel
PublicationIn this study, the connection between total strain energy density and fracture surface topography is investigated in additively manufactured maraging steel exposed to low-cycle fatigue loading. The specimens were fabricated using laser beam powder bed fusion (LB-PBF) and examined under fully-reversed strain-controlled setup at strain amplitudes scale from 0.3% to 1.0%. The post-mortem fracture surfaces were explored using a non-contact...
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PCR-Based Genotyping of Mycobacterium tuberculosis with New GC-Rich Repeated Sequences and IS6110 Inverted Repeats Used as Primers.
PublicationW pracy przedstawiono nową metodę genotypowania Mycobacterium tuberculosis. Zastosowanie oligonukleotydu Mtb1 5'-CCG-GCG-GGG-CCG-GCG-G lub Mtb2 5'-CGG-CGG-CAA-CGG-CGG-C wraz z oligonukleotydami specyficznymi do terminalnych sekwencji elementu insercyjnego IS6110 pozwala na różnicowanie szczepów Mycobacterium tuberculosis w metodzie PCR. Opracowana metoda może być wykorzystana w badaniach epidemiologicznych gruźlicy.
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Wpływ pochylenia wiązek promieniowania anten sektorowych na zasięg i pojemność interfejsu radiowego WCDMA/FDD
PublicationW referacie omówiono wpływ mechanizmów elektrycznego i mechanicznego pochylania wiązki promieniowania anten sektorowych na zasięg i pojemność interfejsu radiowego WCDMA/FDD systemu UMTS. Przedstawiono wyniki badań symulacyjnych wpływu obu tych mechanizmów na charakterystyki systemu.
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Specjalne budownictwo stalowe. Areny XXI wieku - stadiony
PublicationOmówiono prace związane z projektem dotyczącym realizacji mistrzowstw świata w piłce nożnej. Przedstawiono problemy związane z poszczególnymi obiektami stadionowymi. Omówiono ogólne kierunki w zakresie rozwiązań nowoczesnego obiektu.
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Tyche. Beiträge zur Alten Geschichte, Papyrologie und Epigraphik
Journals -
Asynchronous motor nonlinear control with inverter output LC filter
PublicationFiltr wyjściowy falownika jest stosowany w napędach elektrycznych prądu przemiennego o regulowanej prędkości w celu wygładzenia przebiegów prądów i napięć zasilających silnik. Zastosowanie filtru utrudnia realizację precyzyjnych metod sterowania silnikami, szczególnie w przypadku napędów bezczujnikowych (tj. bez czujnika prędkości obrotowej wału silnika). Ponieważ, ze względów praktycznych, nie stosuje się pomiarów prądów i napięć...
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The potential of LC–MS technique in direct analysis of perfume content
PublicationPerfumes are products that consist of a wide range of natural and synthetic compounds. Due to complex composition, the determination of their ingredients is a difficult task. Most of the perfume components are either volatile or semi-volatile; however, most of the attention has been paid to volatile ones, and thus, gas chromatography or electronic noses are generally used. Nevertheless, in this study, liquid chromatography coupled...
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Processing and properties of Al-Si-Fe-Cr in situ composites
PublicationPraca jest kontynuacją badań nad wytwarzaniem tanich kompozytów in situ o osnowie stopu Al-Si wzmocnionego związkami międzymetalicznymi Al-Fe-Si lub Al-Fe-Cr-Si, otrzymanych poprzez reakcję ciekłego stopu Al (Al-Si11, Al-Si25) z proszkiem Fe lub Cr. Żelazo zostało wybrane ze względu na niską cenę, niską temperaturę wytwarzania, wysoką reaktywność z Al i heksagonalną sieć krystalograficzną związku Al-Fe-Si, co sprzyja tworzeniu...
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Algebraic model of continuous time Gm-LC filters and applications.
PublicationW pracy zaprezentowano model algebraiczny filtrów Gm-LC czasu ciągłego i jego wybrane zastosowania. Zaproponowany model obejmuje struktury pracujące zarówno w trybie napięciowym jak i prądowym. Użyteczność opracowanego modelu potwierdzono na przykładzie syntezy eliptycznego filtru Gm-LC rzędu nieparzystego.
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Charakterystyka kawitacyjna laserowo obrabianych napoin Fe-Cr-Mn
PublicationPrzedstawiono badania odporności kawitacyjnej napoin Fe-Cr-Mn w dwóch przypadkach: bez dodatkowej obróbki powierzchniowej oraz po przetapianiu powierzchni napoiny wiązką lasera CO2 o mocy 1000W. Oceniano głębokość i stopień umocnienia warstwy wierzchniej.
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Measurements of electrically small antenna radiation patterns in non-anechoic environments using TGM
Open Research DataThe dataset contains raw and processed measurements of radiation pattern characteristics performed in non-anechoic regime for four antenna structures: a spline-parameterized Vivaldi structure, a compact spline-based monopole, super-ultrawideband antenna, and a quasi-Yagi component. The responses have been obtained at the selected frequencies of interest...
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The effect of mechanical coupling on the beam pattern of a multielementarray
PublicationW artykule opisano nową metodę redukcji listków bocznych hydroakustycznej anteny wieloelementowej. Wykorzystano tu efekt ważenia amplitud sygnałów odbieranych przez poszczególne elementy poprzez kontrolowane ich mechaniczne sprzężenie. Opisane zostały wyniki badań kilku modeli anten zbudowanych z pięciu elementów. Wyniki badań zostały zweryfikowane obliczeniami symulacyjnymi. Stwierdzono, zarówno na drodze eksperymentalnej jak...
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Zmodyfikowana metoda monopulsowa w wielowiązkowych filtrach przestrzennych sonarów pasywnycj
PublicationZwiększenie dokładności określania namiaru celu można uzyskać w sonarach stosując metodę monopulsową. W konwencjonalnych sonarach polega ona na wyrównywaniu sygnałów w dwóch sąsiednich wiązkach poprzez obrót anteny. W cyfrowych sonarach wielowiązkowych obrót anteny można zastąpić obliczeniami, które przedstawiono w referacie. Opracowaną metodę poprawy dokładności namiaru pokazano na przykładzie szerokopasmowego sonaru wielowiązkowego...
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Susceptibility of Cr-Ni-Mn steel to the hydrogen degradation in boiler fuel = Podatnośc stali Cr-Mn-Ni na niszczenie wodorowe w paliwie kotłowym
PublicationStal 34HNM poddana różnym obróbkom cieplnym wykazała skłonność do korozji naprężeniowej w pomiarach ze stałą niską szybkością rozciągania i do zmęczenia korozyjnego niskocyklowego. Mechanizmem zniszczenia była degradacja wodorowa. Możliwe źródła pochłaniania wodoru to: korozja, degradacja węglowodorów z tworzeniem się kwasów organicznych i promotorów wnikania wodoru.
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Simple 60 GHz Switched Beam Antenna for 5G Millimeter-Wave Applications
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Molecular Mechanisms Associated with ROS-Dependent Angiogenesis in Lower Extremity Artery Disease
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Monitoring of myocardium state during off-pump coronary artery by-pass grafting
PublicationW pracy przedstawiono technikę pomiarową do oceny procesów zachodzących podczas operacji przesłowania aortalno-wieńcowego wymagających zatrzymania przepływu krwi. Zaproponiwany system i metoda pomiarowa przewidziane są do wykorzystania podczas opercacji na tzw. bijącym sercu. Pokazano przykłady rejestrowanych sygnałów przydatnych do oceny stanu mieśnia serca oraz dokonano oceny właściwości pomiarowych zastosowanych technik.
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Filtering EBG Structures Implemented in Coplanar Waveguide Feedline of Planar Slot Antenna
PublicationA novel compact dual-band slot antenna fed by a coplanar waveguide (CPW) incorporating electromagnetic band gap (EBG) structures has been proposed. At first, a classic wideband slot antenna fed by a CPW, dedicated to work in 2 ÷ 18 GHz band, has been designed. Subsequently, by adding simple EBG filtering structures into a CPW feedline, a dual-band performance ranging from 2.5 to 5.3 GHz and from 13.5 to 16.3 GHz, with the voltage...
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Multi-Objective Design Optimization of Compact Quasi-Isotropic Dielectric Resonator Antenna
PublicationMulti-objective optimization of a quasi-isotropic dielectric resonator antenna (DRA) is presented. Utilization of variable-fidelity electromagnetic (EM) DRA models, response surface approximations, and response correction techniques, allows us to obtain—at a low computational cost—a set of alternative antenna designs representing the best possible trade-offs between three conflicting objectives: antenna size, its reflection response,...
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Rotational Design Space Reduction for Cost-Efficient Multi-Objective Antenna Optimization
PublicationCost-efficient multi-objective design of antenna structures is presented. Our approach is based on design space reduction algorithm using auxiliary single-objective optimization runs and coordinate system rotation. The initial set of Pareto-optimal solutions is obtained by optimizing a response surface approximation model established in the reduced space using coarse-discretization EM simulation data. The optimization engine is...
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Fast Simulation-Driven Design of a Planar UWB Dipole Antenna with an Integrated Balun
PublicationThe paper presents a design of an ultra-wideband (UWB) antenna with an integrated balun. A fully planar balun interfacing the microstrip input of the structure to the coplanar stripline (CPS) input of the dipole antenna is introduced. The electromagnetic (EM) model of the structure includes the dipole, the balun, and the microstrip input to account for interactions over the UWB band. The EM model is adjusted for low reflection...
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Inverse surrogate modeling for low-cost geometry scaling of microwave and antenna structures
PublicationPurpose–The purpose of this paper is to investigate strategies for expedited dimension scaling ofelectromagnetic (EM)-simulated microwave and antenna structures, exploiting the concept of variable-fidelity inverse surrogate modeling.Design/methodology/approach–A fast inverse surrogate modeling technique is described fordimension scaling of microwave and antenna structures. The model is established using referencedesigns obtained...
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Performance evaluation of GPS anti-spoofing system based on antenna array processing
PublicationThis article concerns the problem of detection and mitigation of spoofing attacks in Global Navigation Satellite Systems. First, background information about spoofing and its possible countermeasures is provided. Next, concept of a novel GPS anti-spoofing system based on antenna array processing is presented and implementation of prototype of this system is described. The third section outlines the performance evaluation of proposed...
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Low-cost multi-objective optimization and experimental validation of UWB MIMO antenna
PublicationPurpose–The purpose of this paper is to validate methodologies for expedited multi-objective designoptimization of complex antenna structures both numerically and experimentally.Design/methodology/approach–The task of identifying the best possible trade-offs between theantenna size and its electrical performance is formulated as multi-objective optimization problem.Algorithmic frameworks are described for finding Pareto-optimal...
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Coplanar Waveguide Fed Ultra-Wideband Antenna Over the Planar and Cylindrical Surfaces
PublicationThe investigation of coplanar waveguide fed ultra-wideband antenna and the influence of the proximity of different materials on the reflection coefficients and radiation character-istics is presented. The antenna is composed of two circular coplanar strips which enclose slot aperture of similar shape and is designed on a thin and flexible substrate. From the modeling and experimental tests the antenna shows good performance in...
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Fast Multi-Objective Antenna Design Through Variable-Fidelity EM Simulations
PublicationA technique for fast multi-objective antenna optimization is introduced. A kriging interpolation surrogate constructed from sampled coarse-mesh EM simulations is utilized by multi-objective evolutionary algorithm (MOEA) to obtain the initial Pareto front approximation. The surrogate is defined in a subset of the original design space, determined by means of independently optimized individual objectives. Response correction techniques...
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Computationally Efficient Multi-Objective Optimization of and Experimental Validation of Yagi-Uda Antenna
PublicationIn this paper, computationally efficient multi-objective optimization of antenna structures is discussed. As a design case, we consider a multi-parameter planar Yagi-Uda antenna structure, featuring a driven element, three directors, and a feeding structure. Direct optimization of the high-fidelity electromagnetic (EM) antenna model is prohibitive in computational terms. Instead, our design methodology exploits response surface...
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Efficient Multi-Objective Simulation-Driven Antenna Design Using Co-Kriging
PublicationA methodology for fast multi-objective antenna optimization is presented. Our approach is based on response surface approximation (RSA) modeling and variable-fidelity electromagnetic (EM) simulations. In the design process, a computationally cheap RSA surrogate model constructed from sampled coarse-discretization EM antenna simulations is optimized using a multi-objective evolutionary algorithm. The initially determined Pareto...
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Enhanced switched parasitic antenna with switched active monopoles for indoor positioning systems
PublicationThis paper presents the concept of enhanced reduced-size steerable antenna array with two rows of switched active and passive elements. Designed array is similar to ESPAR antenna but it has a set of switched monopoles instead of central one. It is intended for 2.4 GHz ISM applications with emphasis on indoor positioning systems (IPS). Proposed antenna provides improved radiation parameters and reduced dimensions in comparison to...
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Comprehensive comparison of compact UWB antenna performance by means of multi-objective optimization
PublicationAn optimization-based procedure for comprehensive performance comparison of alternative compact UWB antenna topologies is discussed. The assessment of the antenna performance is conducted with respect to the structure size and its reflection response. More specifically, the best possible tradeoffs between these two figures of merit are identified through multiobjective optimization at the level...
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Objective relaxation algorithm for reliable simulation-driven size reduction of antenna structure
PublicationThis letter investigates reliable size reduction of antennas through electromagnetic-driven optimization. It is demonstrated that conventional formulation of the design task by direct footprint miniaturization with imposing constraints on electrical performance parameters may not lead to optimum results. The reason is that—in a typical antenna structure—only a few geometry parameters explicitly determine the antenna footprint,...
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UHF ESPAR antenna for simple Angle of Arrival estimation in UHF RFID applications
PublicationAn electronically switched beam antenna for localization of passive UHF RFID tags based on a simple Angle of Arrival (AoA) technique is proposed‥ Detailed antenna design and realization are presented together with corresponding simulations and measurement results. Experimental tests with passive UHF RFID tag show the validity of theoretical assumptions for application of the antenna in UHF RFID based localization systems.
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Low-Cost Data-Driven Surrogate Modeling of Antenna Structures by Constrained Sampling
PublicationFull-wave electromagnetic (EM) analysis has become one of the major design tools for contemporary antenna structures. Although reliable, it is computationally expensive which makes automated simulation-driven antenna design (e.g., parametric optimization) difficult. This difficulty can be alleviated by utilization of fast and accurate replacement models (surrogates). Unfortunately, conventional data-driven modeling of antennas...
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Pareto Ranking Bisection Algorithm for Expedited Multi-Objective Optimization of Antenna Structures
PublicationThe purpose of this letter is introduction of a novel methodology for expedited multi-objective design of antenna structures. The key component of the presented approach is fast identification of the initial representation of the Pareto front (i.e., a set of design representing the best possible trade-offs between conflicting objectives) using a Pareto-ranking bisection algorithm. The algorithm finds a discrete set of Pareto-optimal...
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Size-Reduction-Oriented Design of Compact CPW-Fed UWB Monopole Antenna
PublicationA structure and design optimization of compact CPW-fed UWB monopole antenna is presented. Explicit size reduction through constrained numerical optimization of all relevant geometry parameters of the structure leads to a very small footprint of only 321 mm2. At the same time, a very wide antenna bandwidth is achieved from 3.1 GHz to 17 GHz.
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Low-Profile ESPAR Antenna for RSS-Based DoA Estimation in IoT Applications
PublicationIn this paper, we have introduced a low-profile electronically steerable parasitic array radiator (ESPAR) antenna that can successfully be used to estimate the direction-of-arrival (DoA) of incoming signals in wireless sensor network (WSN) applications, in which the height of the complete antenna has to be low. The proposed antenna is over three times lower than high-profile ESPAR antenna designs currently available in the literature...
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A Simple-Topology Compact Broadband Circularly Polarized Antenna With Unidirectional Radiation Pattern
PublicationIn this letter, a geometrically simple, reflector-backed single-point-fed circularly polarized (CP) antenna with unidirectional radiation pattern is presented. The structure comprises a simple coplanar waveguide (CPW) feeding circuit with an open slot etched on one side of the coplanar ground. The enhanced CP bandwidth is obtained by combining the loop mode, the slot mode, and the asymmetrical configuration of the coplanar ground...
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A Compact Circularly Polarized Antenna With Directional Pattern for Wearable Off-Body Communications
PublicationThis letter presents a geometrically simple and compact circularly polarized (CP) antenna with unidirectional radiation characteristics for off-body communications. The proposed antenna is based on a microstrip line monopole extension from a coplanar waveguide (CPW) and a protruded stub from one side of the coplanar ground plane along the length of the monopole. The orthogonal components of equal amplitudes required for circular...
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Generalized Pareto ranking bisection for computationally feasible multi-objective antenna optimization
PublicationMulti-objective optimization (MO) allows for obtaining comprehensive information about possible design trade-offs of a given antenna structure. Yet, executing MO using the most popular class of techniques, population-based metaheuristics, may be computationally prohibitive when full-wave EM analysis is utilized for antenna evaluation. In this work, a low-cost and fully deterministic MO methodology is introduced. The proposed generalized...
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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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Rapid Antenna Optimization with Restricted Sensitivity Updates by Automated Dominant Direction Identification
PublicationMeticulous tuning of geometry parameters turns pivotal in improving performance of antenna systems. It is more and more often realized using formal optimization methods, which is demonstrably the most efficient way of handling multiple design variables, objectives, and constraints. Although in some cases a need for launching global search arises, a typical design scenario only requires local optimization, especially when a decent...