Search
Filters
total: 10809
filtered: 7755
-
Catalog
- Publications 7755 available results
- Journals 666 available results
- Conferences 47 available results
- People 361 available results
- Inventions 3 available results
- Projects 48 available results
- Laboratories 3 available results
- Research Teams 2 available results
- e-Learning Courses 792 available results
- Events 96 available results
- Offers 1 available results
- Open Research Data 1035 available results
Chosen catalog filters
displaying 1000 best results Help
Search results for: compact power divider, e-plane groove gap waveguide, mmwave, ridge gap waveguide, wideband design.
-
Design of Compact and Wideband Groove Gap Waveguide-Based Directional Couplers
PublicationThis paper proposes a compact cross-shaped groove gap waveguide structure for creating wideband and compact directional couplers with different coupling levels. Groove gap waveguide technology is applied to overcome fabrication challenges of printed and hollow waveguide structures in high frequency bands. The validity of the novel concept is demonstrated through the design and evaluation of several compact broadband directional...
-
Millimeter Wave Wideband and Low-Loss Compact Power Divider Based on Gap Waveguide: For Use in Wideband Antenna Array System
PublicationThis paper presents a wideband and low-loss design of a compact power divider based on gap waveguide technology. The proposed power divider consists of two adjacent E-plane groove gap waveguide and a small ridge section to couple and equally divide the EM energy from the input E-plane groove gap waveguide to the two output ones in-phase. The simulation results show that the proposed waveguide power divider has about 40% impedance...
-
A Wideband Rotary-Joint-Free H-Plane Horn Antenna With 360° Steerable Radiation Pattern Using Gap Waveguide Technology
PublicationConsidering the limitations of electronically steerable antennas such as limited steering span, gain degradation for large steering angles, complexity, and cost, this article is focused on the design of a simple mechanically steerable H-plane horn antenna. It is shown that since there is no need for an electrical connection between the top and bottom sections of a gap waveguide (GWG), if a sectoral horn is properly designed and realized...
-
D-Band High Gain Planer Slot Array Antenna using Gap Waveguide Technology
PublicationA D-band high gain slot array antenna with corporate-fed distribution network based on gap waveguide structures is proposed at 140GHz. To overcome the fabrication challenges at such high frequency, the gap waveguide technology is deployed in which good electrical contact between different parts of the waveguide structure is not required. The proposed sub-array has four radiating slots that are excited by a groove gap cavity and...
-
Low-Loss Mechanically Tunable Resonator and Phase Shifters in Groove Gap Waveguide Technology
PublicationThis research is focused on the design and realization of high-performance high-power variable phase shifters in groove gap waveguide technology. Specifically, it is shown that the unique characteristic of groove gap waveguides, which is its proper operation without the need for electrical connection between the top and bottom sections of the waveguide, can be used to design mechanically tunable devices. Using the proposed method,...
-
Microwave Alignment and Displacement Sensors in Groove Gap Waveguide Technology
PublicationThis paper is aimed at presenting highly sensitive microwave displacement and alignment sensors. With this goal, the method of realizing mechanically tunable cavity resonators in groove gap waveguides technology is presented. The resonance frequency of the cavity is then used for displacement sensing. It is also demonstrated that the symmetry properties of a pair of groove gap waveguide cavities can be used to improve the robustness...
-
A gap waveguide-based mechanically reconfigurable phase shifter for high-power Ku-band applications
PublicationThis paper presents a novel design of a low-loss, reconfgurable broadband phase shifter based on groove gap waveguide (GGW) technology. The proposed phase shifter consists of a folded GGW and three bends with a few pins forming the GGW and one bend attached to a movable plate. This movable plate allows for adjustments to the folded waveguide length, consequently altering the phase of electromagnetic waves. The advantage of GGW...
-
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...
-
Design of a Coplanar Waveguide-Fed Wideband Compact-Size Circularly Polarized Antenna and polarization-sense alteration
PublicationThis paper presents the design and validation of a geometrically simple circularly polarized(CP) structure featuring flat gain in the sub-6 GHz 5th generation spectrum. The proposed structure is based on coplanar-waveguide-fed, modified wide slot etched in the ground plane. For generating CP waves, the coplanar ground planes are designed with slight asymmetry in both the horizontal and vertical directions. Furthermore, the ground...
-
Metamaterial-Based Series-Fed Antenna with High Gain and Wideband Performance for Millimeter Wave Spectrum Applications
PublicationThis paper presents a high-gain, wideband series-fed antenna designed for 5G millimeter-wave (MMW) applications. The structure employs a substrate-integrated waveguide (SIW)-based power splitter and metamaterials (MMs). The power divider functions effectively at 27.5 GHz, exhibiting an impedance bandwidth from 26.9–28.6 GHz. The series-fed dipole is assembled on the SIW-based power splitter, incorporating four dipoles with varying...
-
High Dynamic Range Microwave Displacement and Rotation Sensors Based on the Phase of Transmission in Groove Gap Waveguide Technology
PublicationThis research is focused on the design and realization of displacement sensors in gap waveguide technology. It is shown that with a small but fundamental change in the structure of a conventional gap waveguide, a linear displacement can be sensed. To this end, a unique feature of gap waveguides, i.e. the fact that no electrical connection between the top and bottom parts of the gap waveguide is required, is used. It is further shown...
-
Enhanced-Performance Circularly Polarized MIMO Antenna with Polarization/Pattern Diversity
PublicationDesign of a compact wideband circularly polarized (CP) multiple-input multiple-output (MIMO) antenna with polarization diversity is proposed and characterized for off-body communication. The antenna is based on a simple coplanar waveguide (CPW)-fed monopole extension of the microstrip line. The orthogonal field components required by CP are induced using a simply modified right/left side ground plane. In particular, a stub extending...
-
Pin-on-Substrate Gap Waveguide: An Extremely Low-Cost Realization of High-Performance Gap Waveguide Components
PublicationConsidering the limitations of currently available technologies for the realization of microwave components and antennas, a trade-off between different factors including the efficiency and fabrication cost is required. The main objective of this letter is to propose a novel method for the realization of gap waveguides (GWGs) that take advantage of conventional PCB fabrication technology, thus are low cost and light weight. Moreover,...
-
Compact broadband multi-way 1:6 power divider
PublicationThis paper introduces a design flow of a microstrip multi-way 1:6 power divider incorporating photonic bandgap (PBG) structures. Themethod proposed has enabled the achievement of considerable miniaturization (15%) together with transmission characteristics enhancement(141% bandwidth). Measured results show significant similarity to theoretical characteristics, which proves the attractiveness of presented design methodology.
-
Novel topology of compact coplanar waveguide resonant cell low-pass filter
PublicationIn this study, a novel pseudoelliptic function low-pass filter (LPF) constituted by a compact coplanar waveguide resonant cell has been designed and manufactured. The lumped-element seven-pole prototype has been adequately realized by using complementary perturbations located both in signal line and ground plane metallization. The fabricated uniplanar LPF offers a compact size of 5.6 x 9.8 mm2, return loss better than 26 dB over...
-
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...
-
Highly-Compact Dual-Band Bandpass Waveguide Filter Based on Cross-Shaped Frequency-Dependent Coupling
PublicationThis work reports the design of an original class of highly-compact dual-band bandpass filter based on dual-mode waveguide resonators inter-coupled through a novel type of frequency-dependent coupling (FDC). The devised FDC consists of a cross-shaped metallic structure placed in the broad wall of a rectangular waveguide. This FDC produces two additional poles and three extra transmission zeros (TZs). Specifically, each pole is...
-
Inline Waveguide Filter With Compact Frequency-Dependent Coupling Producing Two Additional Poles and Three Transmission Zeros
PublicationThis work reports a compact frequency-dependent coupling (FDC) structure introduced in a rectangular waveguide, which allows to generate two additional in-band transmission poles and three transmission zeros (TZs). This serves to increase the order/selectivity of the waveguide bandpass filter in a compact inline topology, thus without the need for any additional space/volume or cross coupling. The proposed FDC consists of a partial-height...
-
Design and experimental verification of multi-layer waveguide using pin/hole structure
PublicationThis study presents a novel technique for minimizing RF leakage in metallic hollow waveguides fabricated using the multilayer split-block method. By integrating a pin/hole wall into the split-block multilayers, a substantial reduction of RF leakage can be achieved while reducing the circuit size and mitigating the performance variations. To validate the proposed approach, a slot antenna fed by single ridge waveguide has been prototyped...
-
Compact Quasi-Elliptic-Type Inline Waveguide Bandpass Filters With Nonlinear Frequency-Variant Couplings
PublicationThis work presents the design techniques to synthesize a class of compact inline quasi-elliptic-type waveguide cavity bandpass filters based on novel nonlinear frequency-variant couplings (NFVCs). These highly dispersive frequency-variant couplings (FVCs) are realized by means of a pair of partial-height posts that are placed at the junctions between every two cavity resonators. Each NFVC produces a transmission pole in between...
-
Substrate Integrated Waveguide-Based Ultra-Compact Self-Heptaplexing Antenna for IoT Connectivity
PublicationThis paper introduces an innovative design of a substrate-integrated waveguide (SIW)-based self-heptaplexing antenna (SHA). The proposed structure is implemented using a combination of circular and rectangular HM-SIW cavities. Furthermore, the antenna contains seven individual patches on top of the SIW cavity to operate at seven distinct frequencies. The microstrip feeding technique has been used to activate seven distinct ports....
-
Substrate-integrated waveguide (SIW) filter design using space mapping
PublicationIn this paper, we present a fast technique for an automated design of microwave filters in substrate integrated wave (SIW) technology. The proposed methodology combines the space mapping technique with a cost function defined using the location of complex zeros and poles of filter’s transfer and reflection function and uses a rectangular waveguide as a surrogate model. The effectiveness of the proposed technique is presented with...
-
Simulation-driven design of compact ultra-wideband antenna structures
PublicationPurpose–The purpose of this paper is to investigate strategies and algorithms for expedited designoptimization and explicit size reduction of compact ultra-wideband (UWB) antennas.Design/methodology/approach–Formulation of the compact antenna design problem aiming atexplicit size reduction while maintaining acceptable electrical performance is presented. Algorithmicframeworks are described suitable for handling various design situations...
-
Analysis of inductive power transfer systems for variable air gap and voltage supply frequency
PublicationThe paper describes an IPT system, by which electrical energy may be transmitted through a large air gap between coils without electrical connection. It presents theoretical and simulation analysis of IPT, which allows for supplying a receiver in the conditions of slow, in relation to the dynamics of power supply, changes in dimension of the air gap. The influence of frequency characteristics of the system on the possible selection...
-
Fast Design Optimization of Waveguide Filters Applying Shape Deformation Techniques
PublicationThis paper presents an efficient design of microwave filters by means of geometry optimization using shape deformation techniques. This design procedure allows for modelling complex 3D geometries which can be fabricated by additive manufacturing (AM). Shape deforming operations are based on radial basis function (RBF) interpolation and are integrated into an electromagnetic field simulator based on the 3D finiteelement method (FEM)....
-
Analysis of single-ground-plane coplanar waveguide
PublicationW pracy przedstawion metodę analizy rodziny koplanarnych linii transmisyjnych z pojedynczym przewodem masy. Oryginalne, nie znane wcześniej wyniki modelowania numerycznego potwierdzone zostały dużą zgodnością z wynikami pomiarów wykonanych dla struktury falowodu koplanarnego z pojedynczym przewodem masy (SGP-CPW.
-
Design of a Patch Power Divider with Simple Structure and Ultra-Broadband Harmonics Suppression
PublicationThis paper introduces a simple H-shaped patch Wilkinson power divider (WPD), which provides ultra wide harmonics suppression band. The presented WPD designed at 1.8 GHz, and exhibits good performance at the operating bandwidth. In the proposed divider structure, two simple patch low-pass filters (LPFs) are employed at each branch, and three open ended stubs are added at each port. The proposed divider, implemented using the aforementioned...
-
Design of Microwave Lossy Filter Based on Substrate Integrated Waveguide (SIW)
PublicationIn this letter, we propose a lossy three-pole Chebyshev filter centered at 5.15 GHz, based on the substrate integrated waveguide (SIW) with scattering characteristics shifted down by 5.68 dB. The filter is composed of three directly coupled SIW cavities with three lossy couplings between nonadjacent resonators. These additional couplings are realized using mixed coupled slot and microstrip lines connected with metal electrode leadless...
-
A Self-Equalized Waveguide Filter With Frequency-Dependent (Resonant) Couplings
PublicationThis letter presents a design of a fifth-order linear phase filter with frequency-dependent couplings. The filter is composed of a triplet that is directly coupled to two resonators at the input and output. To provide group delay flattening a cross-coupling in the trisection has a strongly dispersive character with a negative slope parameter. To achieve this, an E-plane stub with a septum was used. To further improve the filter...
-
Coupled-Resonator Waveguide Filter in Quadruplet Topology With Frequency-Dependent Coupling - A Design Based on Coupling Matrix
PublicationThis letter presents an application of a recently developed coupling matrix synthesis technique to design of coupled-resonator filters with dispersive inter-resonator couplings. This technique is used to design a novel coupled-cavity bandpass filter. Measurements validate the design and confirm effectiveness of the synthesis method. The filter is a four-pole generalized Chebyshev filter with three transmission zeros. Resonators...
-
Control system for contactless electrical energy transfer with varying air gap
PublicationInductive power transfer (IPT) is a system by which electrical energy may be transmitted without electrical connection through a large air gap between coils. Systems usually considered in the literature are the ones with a constant air gap. The paper describes the analysis of IPT, which allows for supplying an electrical load in the conditions of slow, in relation to the dynamics of power supply, changes in the dimensions of the...
-
An algorithm for enhancing macromodeling in finite element analysis of waveguide components
PublicationAn algorithm for enhancing the finite element method with local model order reduction is presented. The proposed technique can be used in fast frequency domain simulation of waveguide components and resonators. The local reduction process applied to cylindrical subregions is preceded by compression of the number of variables on its boundary. As a result,the finite element large system is converted into a very compact set of linear...
-
Waveguide model of the hearing aid earmold system
PublicationBackground The earmold system of the Behind-The-Ear hearing aid is an acoustic system that modifies the spectrum of the propagated sound waves. Improper selection of the earmold system may result in deterioration of sound quality and speech intelligibility. Computer modeling methods may be useful in the process of hearing aid fitting, allowing physician to examine various earmold system configurations and choose the optimum one...
-
Waveguide model of the hearing aid earmold system
PublicationBackground The earmold system of the Behind-The-Ear hearing aid is an acoustic system that modifies the spectrum of the propagated sound waves. Improper selection of the earmold system may result in deterioration of sound quality and speech intelligibility. Computer modeling methods may be useful in the process of hearing aid fitting, allowing physician to examine various earmold system configurations and choose the optimum one...
-
A Trisection Filter Design With Negative Slope of Frequency-Dependent Crosscoupling Implemented in Substrate Integrated Waveguide (SIW)
PublicationThis letter reports on a novel realization of a microwave bandpass filter in a triplet configuration with a frequency-dependent crosscoupling implemented in substrate integrated waveguide (SIW). The design involves implementing dispersive coupling with a negative slope, a feature that allows the capabilities of the classic triplet topology to be extended. In this particular case, the implementation of two transmission zeros on...
-
Miniaturized Inline Bandpass Filters Based on Triple-Mode Integrated Coaxial-Waveguide Resonators
PublicationThis work presents a design technique to implement miniaturized cross-coupled bandpass filters in inline physical configurations based on triple-mode resonators. Triple-mode resonances are obtained by using integrated coaxial-waveguide cavity resonators. They consist of two coaxial conducting posts placed in the sidewalls of a rectangular waveguide cavity. In the proposed triplet, a transmission zero (TZ) can be positioned at any...
-
Efficient model order reduction for FEM analysis of waveguide structures and resonators
PublicationAn efficient model order reduction method for three-dimensional Finite Element Method (FEM) analysis of waveguide structures is proposed. The method is based on the Efficient Modal Order Reduction (ENOR) algorithm for creating macro-elements in cascaded subdomains. The resulting macro-elements are represented by very compact submatrices, leading to significant reduction of the overall number of unknowns. The efficiency of the model...
-
On low-fidelity models for variable-fidelity simulation-driven design optimization of compact wideband antennas
PublicationThe paper addresses simulation-driven design optimization of compact antennas involving variable-fidelity electromagnetic (EM) simulation models. Comprehensive investigations are carried out concerning selection of the coarse model discretization density. The effects of the low-fidelity model setup on the reliability and computational complexity of the optimization process are determined using a benchmark set of three ultra-wideband...
-
Inline Waveguide Filter With Transmission Zeros Using a Modified-T-Shaped-Post Coupling Inverter
PublicationThis letter reports the design techniques for a class 2 of inline waveguide bandpass filters with sharp-rejection capabil3 ities at the lower stopband based on a novel nonlinear-frequency4 variant-coupling (NFVC) structure. The proposed NFVC consists 5 of a modified-T-shaped metallic post (MTP) that is placed at the 6 center of the waveguide broad wall with its open arms lying 7 along the waveguide width. The engineered NFVC structure 8...
-
Rectangular Waveguide Filters Based on Deformed Dual-Mode Cavity Resonators
PublicationIn this paper, a novel design for rectangular waveguide filters with deformed dual-mode (DM) cavity resonators is demonstrated. The new resonant cavity shape is a result of applying shape deformation to the basic rectangular cavity to enable its dual-mode operation. Internal coupling between the two orthogonal cavity modes is realized by geometry deformation, eliminating the need for additional coupling elements. The designs are...
-
Simulation of influence of the air gap asymmetryon voltage waveforms of a synchronous machine
PublicationResults of simulation of a synchronous generator with the air gap asymmetry characterised by eccentricity are presented in the paper. The Lagrange's energy method has been used in derivation of the model equations. Analysis of influence of the air gap asymmetry on characteristics of self and mutual inductances of windings, as well as analysis of induced voltage waveforms as a function of the air gap asymmetry have been performed....
-
Automated design of waveguide filters with frequency-dependent couplings.
PublicationW artykule zaproponowano szybką technikę pozwalającą na automatyczne projektowanie filtrów falowodowych ze sprzężeniami zależnymi od częstotliwości. Procedura optymalizacyjna jest trójetapowa z różnymi funkcjami celu w każdym etapie.
-
Efficient Finite Element Analysis of Axially Symmetrical Waveguides and Waveguide Discontinuities
PublicationA combination of the body-of-revolution and finite element methods is adopted for full-wave analysis of waveguides and waveguide discontinuities involving angular field variation. Such an approach is highly efficient and much more flexible than analytical techniques. The method is performed in two different cases: utilizing a generalized impedance matrix to determine the scattering parameters of a single waveguide section and utilizing...
-
Mind the Gender Wage Gap – the Impact of Trade and Competition on Sectoral Wage Difference
PublicationThis article examines differences between women’s and men’s wages in 18 selected OECD countries in the period 1970-2005. The study is based on 12 manufacturing sector- and skill-specific sets of panel data on the gender wage gap. We apply a system GMM estimator to the extended version of the conditional gender wage gap convergence equation, controlling for sector concentration and industry-specific measures of openness using a...
-
Effect of band gap on power conversion efficiency of single-junction semiconductor photovoltaic cells under white light phosphor-based LED illumination
PublicationOn the basis of the detailed balance principle, curves of efficiency limit of single-junction photovoltaic cells at warm and cool white light phosphor-based LED bulbs with luminous efficacy exceeding 100 lm/W have been simulated. The effect of energy band gap and illuminance on the efficiencies at warm and cool light is discussed. The simulations carried out show that maximum power conversion efficiency at 1000 lx reaches 52.0%...
-
A Circular Waveguide Dual-Mode Filter With Improved Out-of-Band Performance for Satellite Communication Systems
PublicationThis letter presents a novel design for a 3-D-printed circular waveguide dual-mode (CWDM) filter with a modified cavity shape. The modification leads to a wide spurious-free stopband, which is highly desirable for channel separation in waveguide contiguous output multiplexers (OMUXs) in satellite communication systems. The new resonant cavity design is a result of applying shape deformation to a basic circular cavity in order to...
-
Left-handed propagation characteristics of a dielectric and metal-loaded periodic circular waveguide
PublicationIn this paper, a periodic dielectric/metallic rod is located in a circular waveguide to obtain left-handed operation. Two geometries of the dielectric/metallic rod are proposed and examined. The dispersion characteristics of the investigated waveguides are obtained using a surface impedance model. Moreover, equivalent circuit models are proposed allowing for calculation of the dispersion characteristics and scattering parameters...
-
A Geometrically Simple Compact Wideband Circularly Polarized Antenna
PublicationA compact broadband wide-slot circular polarization (CP) antenna is proposed. An inverted L-shape parasitic strip at the open end of a microstrip line extension and a slot modification is applied to attain wideband CP. The advantage of this technique is simplicity which makes it readily re-designable for different frequency bands. To demonstrate the concept, three designs working at different frequencies are obtained. The redesign...
-
Design and Implementation of a Dual-band Filtering Wil-kinson Power Divider Using Coupled T-shaped Dual-band Resonators
PublicationThe paper introduces a novel structure of a dual-band filtering Wilkinson power divider (WPD). Its essential component is a dual-band bandpass filter (BPF), implemented using coupling lines and two T-shaped resonators. The BPF is incorporated into the divider structure to suppress the unwanted harmonics within the circuit. The latter is achieved owing to a wide stopband of the filter. The deigned dual-band WPD can suppress third...
-
Role of nitrogen in evolution of sp2/sp3 bonding and optical band gap in hydrogenated carbon nitride
PublicationDrastic changes in the bonding are found in amorphous hydrogenated carbon nitride (a-CNx:H) film as a function of nitrogen concentration (or N/C ratio). The total C-sp3 fraction and hardness shows a sharp decrease (at N/C = 0.40) whereas optical band gap and resistivity shows a gradual increase as nitrogen concentration increases from 0.07 to 0.58. Raman spectrum of a-CNx:H film is fitted with both Gaussian (integrated intensity...