Wireless power transfer (WPT) technologies have now reached a commercial stage in applications going from consumer electronics, biomedical implants and domestic applications. For electrical cars, WPT offers some new opportunities compared to classical wired charging. Although there exist some commercial cars equipped with wireless charging system, improving design procedures needs to address various

The excitation of surface plasmon-polariton (SPP) waves was delineated for an interface of a metal and an obliquely mounted uniaxially chiral, bianisotropic material with optic axis making an arbitrary angle with the interface plane. Such a material can be fabricated as a parallel assembly of hellixes with the axis of the hellixes making an arbitrary tilt angle with the metallic substrate. The canonical

The fabrication process for a planar helix slow-wave structure (SWS) based on ball-grid array (BGA) technology is developed to be used in the traveling wave tube (TWT). The planar helix layers are structured on two printed circuit boards and the solder ball is used to connect each other upside down. The material properties of the used substrate and also the solder ball connection for being used by

This paper presents a wearable rectenna array fabricated using Cordura textile material for harvesting low-power radio frequency (RF) energy. The dielectric properties of the textile were thoroughly investigated for circuit and antenna design. The rectenna element comprises a linearly polarized patch antenna and a single-stage full-wave Greinacher rectifier. The proposed stack topology helps reduce

An LS Peano fractal antenna, which integrates the self-similarity and spatial filling features of fractal technology, was designed for detecting the ultra-high frequency (UHF) signals generated by gas-insulated switchgear (GIS) partial discharge (PD). Firstly, we used ANSYS HFSS to simulate and design the LS Peano fractal antenna. Then we made the antenna object according to the optimised simulation

It is pointed out how the (sub-structure) characteristic modes of a perfect electrically conducting (PEC) object, in the presence of an electrically very large second PEC object, can be computed using a field-based hybrid method that combines the method of moments (MM) and the geometrical theory of diffraction (GTD). An example is provided to demonstrate this. This possibility has not yet been explicitly

This article presents a circularly polarized 4-port Multiple Inputs Multiple Outputs dielectric resonator-based antenna with two resonating bands for WLAN (5.0 GHz) and WiMAX (3.5 GHz) applications. Important attributes of proposed MIMO-DRA are: (i) Bandwidth enhancement is observed due to the use of ring-shaped ceramic material radiator; (ii) Incorporation of rectangular aperture lead to excite the

Drone borne radar systems have seen considerable advances over recent years, and the application of drone-mounted continuous wave (CW) radars for remote sensing of snow properties has great potential. Regardless, major challenges remain in antenna design for which both low weight and small size combined with high gain and bandwidth are important design parameters. Additional limiting factors for CW

This paper presents an investigation on innovative bandpass negative group delay (NGD) control. The bandpass NGD theory is elaborated with patch antenna-based circuit input impedance. The S-matrix and group delay (GD) models are expressed in function of the circuit geometrical parameters. To validate the no-contact electromagnetic coupling bandpass NGD control, proof of concept is designed, fabricated

In this paper, fundamental properties of solutions to fractional-order (FO) Maxwell's equations are analysed. As a starting point, FO Maxwell's equations are introduced in both time and frequency domains. Then, we introduce and prove the fundamental properties of electromagnetic field in FO electromagnetics, i.e. energy conservation, uniqueness of solutions, and reciprocity. Furthermore, the algorithm

It has been shown that the Hilbert curved electromagnetic band gap (HC-EBG) structure effectively reduces the surface wave excitation in the substrate. This paper investigates the performance of HC-EBG structure for probe-fed microstrip patch phased array antenna. The results show that not only the mutual coupling between two elements is reduced about 20 dB, but also the blind angle is removed. Based

A 3-layer substrate integrated folded magnetoelectric dipole antenna is presented in this paper. The folded metal vias are proposed to broaden bandwidth and miniaturized antenna. Furthermore, the double-arc-edged patch, the single-arc-edged metal plane, side wall and removing shorted end are designed to improve the impedance matching and reduce the operating frequencies. The structure and parameters

A 4*4 multiple-input multiple-output (MIMO) antenna with compact size and good isolation is presented for UWB applications. The concept of polarization diversity is here discussed and employed to satisfy contemporary wireless communication systems requirements. In the proposed antenna, the utilization of a novel circular ripple-shaped decoupling structure and a matching structure are presented to minimize

We solved the problem of Floquet-Bloch waves propagation in the one-dimensional gyrotropic magnetophotonic crystal with transverse magnetic field. New fundamental solutions of the Hill’s equation in crystal layers based on the Floquet theory for a third boundary value problem are obtained in the analytical form. The dispersion equation is found through fundamental solutions. The analysis of the dispersion

We consider propagation of leaky TE waves in a rod filled with nonlinear metamaterial medium. The problem is reduced to the analysis of a nonlinear integral equation with a kernel in the form of the Green function of an auxiliary boundary value problem on an interval. The existence of propagating nonlinear leaky TE waves for the chosen nonlinearity (Kerr law) is proved using the method of contraction

This study proposes an innovative patch antenna design for multi-band operation and high radiation efficiency. The design target is the structural shape of a patch and a ground plane. The operating range of patch antenna is set to both the 5G band (3.4−3.7 GHz) and the Bluetooth range (2.4−2.48 GHz). The design process follows two steps, the genetic algorithm (GA) and the binary method. Although the

We present a study of the dielectric properties and behaviour of dielectric resonator antennas (DRAs) based on SrBi2Nb2O9 (SBN)-Bi2O3 composites. X-ray diffraction is used for structural characterisation of the samples and it indicates the formation of a new phase after the addition of Bi2O3. The temperature coefficient of resonant frequency (τ f) is measured and the results demonstrate that the increment

Impedance bandwidth, multi-band, gain, and circular polarization (CP) are important characteristics of the microstrip antenna. In this paper, these characteristics have been highlighted by designing three different antenna structures. The proposed modified ground plane antenna consists of tilted G-shaped radiator (TGSR), which acts as a radiating element. The overall volume of the proposed antenna

This review is dedicated to the Effective Medium Theory of two-component metamaterials in the broad frequency range from microwaves to visible region. The metamaterials are unbounded periodic 2-D lattice of infinitely long cylinders of circular cross section or unbounded periodic 3-D lattice of spherical particles embedded in a homogeneous isotropic host dielectric. Three types of inclusions are considered:

This paper presents the electrical design of a high power ring-bar TWT amplifier at Ku-band. The design parameters of Slow-wave structure (SWS) were synthesized theoretically. Further, the design was optimized using a computer simulation technology (CST). The dispersion and interaction impedance characteristics were simulated using the eigenmode simulation (EMS) technique at a beam voltage of 14.5 kV

A new low profile broadband directional spiral antenna design on a planar EBG structure is introduced which is suitable for aircraft structural integration. The proposed antenna has the (greater than 4 dBiC) gain and axial ratio (less than 3-dB) bandwidth of 400–800 MHz (except for a narrow frequency range of 505–530 MHz) within a total thickness of one tenth of the wavelength. Meausured peak gain

In order to make an anechoic chamber operate similarly to ideal OATS, various design methods of the anechoic chamber have been studied. Without changing of RAM and major structural design of the rectangle anechoic chamber, we propose a method of automatically designing the shape of a slanted wall anechoic chamber by applying the PSO to 3D deterministic ray tube method. The 3D Deterministic Ray Tube

In this editorial, a compact two element Ultra Wide Band Multiple Input Multiple Output (UWB MIMO) antenna with triple-band notch characteristics is presented. A single Two Via Compact Electromagnetic Band Gap (TVC-EBG) structure is used to achieve triple-band notches at WiMAX, WLAN, and X Band. An inverse L-shaped stub is inserted in the ground plane of the antenna to diminish mutual coupling amid

Transmission of a normally incident plane wave through a pixelated metasurface with meta-atoms made up of graphene-patched and InSb-patched pixels on a silicon substrate was simulated using CST Microwave StudioTM2019 software. This metasurface is electrically controllable due to the graphene-patched pixels, and it is magnetically as well as thermally controllable due to the InSb-patched pixels. A tricontrollable

By modifying the shape of a rectangular dielectric resonator antenna (DRA), a wideband circularly polarized (CP) radiator is introduced. The modified structure is composed of two L-shaped dielectric pieces stacked onto each other. The resulting geometry is similar to a two-turn helix with a rectangular cross section. Placing a coaxial probe adjacent to the sidewall of the DRA excites multiple orthogonal

(2020). Waves in resonant metasurfaces. Journal of Electromagnetic Waves and Applications: Vol. 34, Waves in Resonant Metasurfaces, pp. 1309-1313.

In this work, a wideband microwave resonating-type absorber is investigated in terms of metal backed metamaterial absorber (MMA). Expanded graphite-silicone (EG-Si) composite is encapsulated in the flexible silicone rubber matrix to build periodic unit cell of the MMA. Microwave material characterization of the EG-Si composites with different weight percentages (1, 3, 5, 7, 9 and 11 wt. %) is carried

A high-efficiency tri-band artificial electromagnetic (EM) polarization manipulating metasurface is proposed, which is employing two metal rectangle rings composed of a single-layer reflectance surface. There are three frequency bands generated by the artificial EM polarization manipulating metasurfaces, with 3-dB bandwidth at 9.10–12.40, 15.55–23.80 and 24.71–30.00 GHz, and the relative bandwidth

Conformal techniques, based on the covariance of Maxwell's electrodynamics under the full conformal group in four spacetime dimensions, are discussed in relation with the constant input impedance properties of frequency-independent antennas. In particular, we show that by applying suitable conformal transformations to existing self-complementary planar structures like logarithmic spirals, the constant

The core-shell nanoparticles have received much attention due to their potential applications in biomedicine, molecular detection, catalyst, and cancer therapy. In this work, the optical properties of Fe-Ag nanoparticles in core-shell configuration are studied by using the discrete dipole approximation (DDA) method. The Fe-core is coated with varying Ag-shell thicknesses for different shapes and sizes

Magnetic-free broadband circulator structure based on three switched reflection type delay lines with a total electrical length of 180-degree at the switching frequency is investigated. The nonreciprocal transmission property is modeled and simulated, the impedance mismatching property and reconfigurable direction are studied. A prototype magnetic-free circulator circuit is designed and fabricated

In this article, we propose a model to obtain negative electrical permittivity in metamaterials using a conductor wire of rectangular cross-sectional geometry. Plasma frequency in the GHz range is determined in terms of the wire geometry. This new composite dielectric, which has the property of negative electrical permittivity below the plasma frequency, opens new possibilities for GHz devices. Finally

We present an artificial metasurface comprised of a metallic monolayer having a designed functionality of an Artificial Magnetic Conductor (AMC). The metasurface is designed to operate as a broadband AMC for incident electromagnetic waves polarized in a specific direction, while it works as a pass-band filter for waves orthogonally polarized to the previous direction. Hence the design presents a dual

(2020). Massive MIMO toward 5G. Journal of Electromagnetic Waves and Applications: Vol. 34, Massive MIMO Toward 5G, pp. 1091-1094.

This paper presents a novel two-element multiple input multiple output (MIMO) reconfigurable antenna that can be switched among 600 MHz, 1.8, 2.4, 3.5, and 5.5 GHz bands. The proposed antenna consists of two semi-circular ring-shaped strip-lines and a rectangular slot on the top conducting layer of the substrate and a U-shaped slot, etched on the bottom side of the substrate. Frequency reconfigurable

In this paper, we design a compact MIMO antenna with high isolation. The antenna covers 2.5/5.8 GHz frequency bands, which are allocated for Wi-MAX / WLAN applications. The suggested MIMO antenna consists of two identical F-shaped monopole antenna elements, which are symmetrically positioned on the top side of an FR-4 substrate. To increase the isolation between the two radiating elements, a T-shaped

A low-profile multi-input-multi-output (MIMO)/diversity antenna suitable for wireless local area network (WLAN) applications is presented. In the proposed antenna, two identical elements (each of size 20 × 47 mm2) are designed to operate at 2.4 GHz and other two identical elements (each of size 20.5 × 20 mm2) at 5.8 GHz. All elements of the proposed diversity antenna are printed on 1.6 mm thick FR-4

This paper is presenting two different microstrip antennas (LHCP and RHCP antennas). It can explain the effects of S-shape and Z-shape slots for left-hand circular polarization and right-hand circular polarization respectively. Both types of slots are used to convert linear polarized antenna into the circularly polarized antenna. It is simulated with the help of CST-2015 and HFSS2018 design software

This paper mainly focuses on the electromagnetic modeling aspect of the digital rock physics to understand the relationship between the micro-structures and contents within the structure to their electrical properties. This is achieved by using the 3D rock micro-CT images and performing electromagnetic modeling using the 3D numerical mixing law (finite difference method based), which is a robust numerical

An efficient analytical method has been proposed for predicting the shielding effectiveness (SE) and resonances of a metallic enclosure with multiple apertures against an external incident plane wave. First, the electromagnetic (EM) field distribution within the enclosure through multiple apertures is represented by the equivalent electric and magnetic dipole moments based on the Bethe’s theory for

In this editorial, a compact two element Ultra Wide Band Multiple Input Multiple Output (UWB MIMO) antenna with triple-band notch characteristics is presented. A single Two Via Compact Electromagnetic Band Gap (TVC-EBG) structure is used to achieve triple-band notches at WiMAX, WLAN, and X Band. An inverse L-shaped stub is inserted in the ground plane of the antenna to diminish mutual coupling amid

An efficient analytical method has been proposed for predicting the shielding effectiveness (SE) and resonances of a metallic enclosure with multiple apertures against an external incident plane wave. First, the electromagnetic (EM) field distribution within the enclosure through multiple apertures is represented by the equivalent electric and magnetic dipole moments based on the Bethe’s theory for

This paper presents a novel high gain rectangular microstrip patch antenna (RMSA) with vertically placed Yagi elements. The antenna is fed by a coaxial probe to excite TM01 fundamental waves at 2.4GHz, which is suitable for wireless local area network (WLAN) applications. In order to increase the antenna gain, Yagi elements are placed in groups of 5, on each side of the substrate in order to serveas

A novel and simple scheme to generate Ultra-wideband (UWB) doublet signal with tunable notch band based on a tunable delay-line filter is presented. The first-order differentiation is realized by a dual-drive Mach–Zehnder modulator (DD-MZM), which differentiates the Gaussian pulses to the monocycle pulses. Subsequently, the UWB monocycle pulses are transmitted to an optical delay-line filter implemented

This paper is to reconstruct the periodic inhomogeneous dielectric distribution of the scatterer buried in the rough surface. In order to explore the dielectric coefficient distribution of the unknown dielectric object under the rough surface, we emit electromagnetic wave to the object and measure the scattered electromagnetic wave above the rough surface. Base on Green's identity and the induced current

This article deals with a new hybrid approach combining a Moment Method (MOM), with the Geometrical Theory of Diffraction (GTD), this approach evaluates the currents surface on the microstrip antenna placed in the rectangular Electric Magnetic Electric Magnetic(EMEM) Waveguides. The incident field is taken as a TEM polarized plane wave in the principal plane. The new hybrid current function based on

Using the perturbation theory (PT), reflected field both in specular and non specular directions from a slab made of topological insulator (TI) material with rough interface is studied. The specular reflections are described by zeroth order terms of the perturbation series while non specular reflections are associated with higher order terms. To describe the surface states on the TI, γ-model characterized

We report a broadband ultra-high frequency (UHF) radio frequency identification (RFID) tag antenna of compact size mounted on a metallic object in a near field communication (NFC) RFID system. One half of the square radiation patch has a semi-annular strip feedline embedded inside a semicircle-shaped slot to improve the antenna bandwidth and gain, and the other half of the radiation patch has an L-shaped

The aim of this paper is to correct errors of a published study [Afzaal M, Syed A, Imran A, et al. Scattering of electromagnetic plane wave by a PEC strip in homogeneous isotropic chiral medium. Journal of Electromagnetic Waves and Applications. 2014;28(8):999–1010]. The investigation is a prominent and attractive subject in the field of electromagnetic scattering that has studied the electromagnetic

In this paper, a compact wideband circularly polarized slot antenna consisting of two L-shaped resonators is proposed. The slot antenna is loaded with a band-stop frequency selective surface (FSS) reflector to improve the gain of the antenna and to reduce the profile of the antenna. The radiation and scattering characteristics of FSS loaded slot antenna are compared with the metallic reflector loaded

This paper presents a novel compact high-isolation cavity-backed inverted U-shaped slot antenna using substrate-integrated waveguide (SIW) for C-band applications. The SIW cavity is loaded by an inverted U-shaped slot that produces two fictitious aperture for radiation at two distinct frequency bands and to exhibit self-diplexing antenna (SDA) characteristics. Two orthogonal microstrip feed lines are

In this paper, an X-band perfect cross-polarization convertor (CPC) that consists of Γ-shaped metal patch imprinted on a metal-backed FR-4 dielectric substrate is designed, analyzed, and characterized. The unit cell dimensions of the developed structure are optimized to achieve more than 99.9% polarization conversion ratio (PCR) for a frequency range of 8–12 GHz (X-band) at normal incidence angle.

The use of strong magnetic fields for brain imaging has shown that increased SNR and resolution can be obtained. Such MRI systems are prone to field non-uniformities that are more likely to appear in deep brain structures making high-quality imaging of deep brain regions a challenge. We investigate the combination of a dipole antenna and Birdcage coil to generate a uniform magnetic field with high

A slot array substrate integrated waveguide antenna is proposed by utilizing novel center inclined slots with non-uniform spaces for imparting feeding advantages of standing and traveling waves. This 1 × 8 array antenna introduces a 13.2 dB gain at center frequency of 59.9 GHz with −10 dB return loss from 58.9 GHz to 60.9 GHz (roughly 2 GHz) and cross-polarization levels more than 45 and 20 dB in E

An analytical solution for the diffraction of plane waves by a right angle impedance wedge which is lying between double negative and positive materials is investigated. In order to satisfy the boundary conditions and shifted shadow boundary, the diffracted fields are divided to subfields. As a result, an anomalous shift of shadow boundary is observed towards to lower surface of the wedge. In addition

In this article, the plane wave diffraction by two strips is studied. Fractional boundary condition is required on strips when the fractional order for each strip is different. The goal of the paper is to investigate the resonant properties of such structures. The mathematical apparatus for the solution of the problem is given. The frequency dependency on the total radar cross-section is constructed

A high transmission tunable metamaterial structure is proposed and manufactured experimentally in the THz range. A transmission peak is achieved at resonance frequency 5.97THz based on the bright-bright modes coupling effect. The transmission peak can be controlled by changing the periodicity P of the unit cell or the diameter D increasing. Moreover, the transmission peak can also be controlled by

The design and development of multiband antenna for useful operating bands are the current state-of-the-art research in the field of antenna research. A simple and single-layer printed multiband radiation structure eliminates the packaging complexity of modern communication devices. The present investigation proposes such simple and single-layer multiband antenna for ISM 2.5 GHz/WiMax 3.5 GHz/WLAN

This paper demonstrates symmetric backward wave quasi-0 dB coupled line coupler (CLC) based on the globe shaped composite right/left-handed transmission line (GS-CRLH-TL). The proposed CLC shows quasi-0 dB backward wave coupling with measured maximum backward coupling level of −0.72 dB at 3.07 GHz. −3 dB bandwidth of the backward coupling region is from 2.75 GHz to 3.34 GHz, corresponding to fractional

The design method of an unequally spaced array was based on the density tapering in the textbook “Antenna theory” in 1969. The effects on grating lobe reductions were shown by radiation pattern calculations. However, no proof for the achievement of density tapering was shown. In this paper, through direct comparisons of the objective amplitude distribution with electric field distributions by electromagnetic