A small structure for chipless RFID tag is proposed; it is inspired by a C-shaped structure and based on HCSRR. This structure has curved strips, which are obtained by fine cutting the substrate from the symmetry of the C-shaped structure as base structure, and then missing part of the path is compensated by creating the PMC boundary condition in the cut-off point according to the image theory. Hence

ABSTRACT In this paper, a dual annular ring patch antenna with high isolation for Multiple Input Multiple Output (MIMO) Satellite application at 4 GHz is presented. The mutual coupling reduction and circular polarization are achieved by some perturbations in annular ring patch and microstrip stubs between antennas. These perturbations will excite two modes which is orthogonal ie. equal amplitude and

Based on the scattering cancellation technique, an approach is proposed to improve the mantle cloak’s performance for electrically large cylinders. The procedure is based on the observation that the number of dominant scattering coefficients and corresponding magnitudes for a cylinder decreases when oriented obliquely to the incident wave. Thus, it is quite advantageous to design a mantle cloak under

In this simulation study, we describe a microstrip transmission line (MTL) array coil, designed to provide a uniform |B1| field along the spinal cord in 7 T MRI. The coil structure was designed by segmenting the spinal cord into four sections according to its shape. The geometry and properties of the MTL coils were optimized individually to obtain a uniform |B1| field distributed according to the shape

A novel printed monopole antenna with simple, low-profile and convenient design is presented in this paper. The antenna composes of a printed monopole antenna and a folded-line stepped impedance resonator (SIR) loaded on the bottom of the substrate. The resonant frequency is decreased by the coupling between the folded-line SIR as the near-field resonant parasitic (NFRP) element and radiation patch

In this paper, a microstrip low-pass filter (LPF) using folded-flag-shaped resonators is designed and presented. Its base resonator length is 12.4 mm, and the proposed low-pass filter has a sharpness of 0.08 GHz. The filter cut-off frequency is 1.44 GHz, and the return loss is reduced to a level of −17 dB, indicating a flat pass-band. Also, the suppressing cell is used to weaken the disturbing harmonics

A novel low-profile tri-band bandpass frequency-selective surface (FSS) is proposed in this paper. The structure is designed by the two-dimensional repetition of a unit cell consisting of four apertures. Each aperture is a combination of T-shaped, U-shaped and a rectangular-shaped aperture aligned horizontally or vertically. The performance of the designed FSS structure is independent of the angle

Based on the MGT positioning method, the performance of combined magnetic beacon is studied. The unit size of beacon is designed as D = 2 cm and L = 8 cm, the performance of different structure magnetic beacons combined have been studied and compared in detail, results show that the magnetic field intensity of cross structure is about 30000nT higher than the orthogonal structure which have generated

ABSTRACT This paper presents a time modulated far-field radiation pattern synthesis of a compact circular antenna array (CAA) by employing a stochastic optimization technique known as grey wolf optimization (GWO). The compactness of the antenna array is achieved by reducing the inter-element distances between the elements of the array which leads to the miniaturization of the antenna array size. On

In this endeavor, a cascade system of an attenuator in series with a Low Noise Amplifier (LNA) will be studied. A discussion on past related works followed by a study of different Attenuator-LNA arrangements not analyzed collectively in those previous works will be presented. This is important for addressing the lowering of system noise figure (NF), which is critical for applications such as GPSs and

A compact coplanar waveguide (CPW)-fed band-notched ultra-wideband (UWB) multiple-input multiple-output (MIMO) flexible antenna on liquid crystal polymer (LCP) substrate is designed. It is composed of two orthogonal elements, tampered feeder and asymmetric ground plate. To improve the port isolation (S 21), an inverted F-shaped branch is added. The measurement results demonstrate that the antenna has

This paper conceptualizes the development of a frequency selective surface (FSS) with 3-D unit cells. The FSS unit cells individually present a three-dimensional structure, whereas collectively these are more like planar FSS. The unit cell substrate has been printed using 3-D printing technique and metallized using copper paint. The 3-D printing offers a degree of freedom to fabricate substrate material

An improved ultra-wideband metamaterial absorber (MA) with high absorptivity in the infrared region is proposed. It features a mixture of copper and GaAs at the top layer, which can greatly raise the bandwidth and absorption rate due to the coupling effect between copper and GaAs. The spectrum with absorption rate of 90% in the infrared region from 98 to 152 THz can be obtained. The input-impedance

In this paper, a compact substrate integrated waveguide (SIW) based dual-band filter which utilizes the dual resonance provided by asymmetric double-ring D-shaped resonators that are incorporated on the upper metallic layer of SIW is communicated. The two passbands are generated well below the cut-off frequency of the SIW due to evanescent mode propagation. Such propagation is responsible for the substantial

We propose a new broadband flexible waterproof antenna suitable for Internet of Things applications. The antenna is comprised of three components: radiating elements fed by a 50-Ω coplanar waveguide transmission line and two layers from an elastomer composite (used as a substrate and top encapsulation) which completely covers the antenna's radiating elements to provide water and dust resistance. An

Magnetic absorbing material (MAM) embedded with electric ring resonator (ERR) is demonstrated to broaden the absorbing bandwidth in low-frequency range. We obtained the relation between input impedance and absorption bandwidth under specific reflection threshold to verify the influence of the embedded ERRs on impedance matching characteristic. Numerical simulations were carried out and the results

An efficient time-domain method based on the waveform relaxation with transverse partitioning (WR-TP) techniques and the delay extraction passive compact circuit (DEPACT) macromodel is presented for evaluating the electromagnetic (EM) transient response of multiconductor transmission lines (MTLs) excited by an external EM field. Firstly, the equivalent distributed sources due to the tangential components

Cloaking structure designs have been widely performed in a form of metamaterial development. However, physics-based design approach makes it difficult to define complex material profiles. This study proposes an alternative design method for multi-directional cloak design via topology optimization method using a dielectric material. The phase field design method, which uses the reaction-diffusion equations

A planar sensor designed using the fourth Hilbert fractal curve iteration for solid material characterization at multiple frequencies is reported in this paper. The fractal curve is self-similar with space-filling properties. The Hilbert fractal geometry is used to form a compact resonator, with a multiband frequency response where miniaturization is achieved since a large transmission line length

A wide band, dual radiator Multiple input multiple output (MIMO) antenna resonating at 2.4 GHz Industrial Scientific and Medical (ISM) band is designed and analysed for the body-centric wireless communication. Defected ground structure (DGS) is used to reduce the antenna size and to achieve wide bandwidth. Moreover, a decoupling slot is also etched in the ground plane to improve the port isolation

ABSTRACT In this letter, a microstrip-line type Bruce array antenna with a wide fan beam and high gain is proposed. The unit composed of the radiating edge and non-radiating edge is repeatedly arranged symmetry to the feeding part. The repeated radiating edge operates as an array of magnetic current sources, which radiates the wide beam pattern in the E-plane and achieves high gain in the H-plane.

ABSTRACT In this paper, the design of an interaction structure for a 10-kW, W-band gyrotron is presented. The beam voltage and beam current are chosen as 30 kV and 1 A, respectively. The mode of interaction was chosen as TE6,2. A parametric design code and a gyro large-signal analysis (LSA) code were developed. The computational steps are discussed in brief. The LSA was done using the in-house developed

Traveling wave tubes are rapidly evolving to provide unprecedented power level in comparison to solid state devices in the millimeter waves region of the spectrum (80–300 GHz) thus enabling a wide range of applications. Wireless communications, imaging, plasma diagnostics, healthcare and many others will gain substantial features if high power at millimeter waves would be available from compact sources

Bandstop filters with single and dual stop-bands were implemented using coupled mode microstrip slot resonators (MSRs) for the first time. With compact and ease of fabrication, the MSRs provide excellent filter response as desired. It is found that the MSRs can offer narrow bandwidth of less than 20% fractional bandwidth and large isolation of more than 40 dB. The designs of MSRs and filters are systematically

In this paper, we present the compact bandpass cavity filters for UHF range. We investigate the properties of coaxial resonators with various numbers of tubular posts from one to four. We show that the resonant frequency can be four times smaller for the four-post resonator in comparison with the single post resonator with the same cavity dimensions. We synthesized and manufactured fifth-order bandpass

An effective method combined with finite element method (FEM) and boundary integral method (BIM) is presented in this paper to study the composite electromagnetic scattering from a 2-D coated object partially buried in a 1-D dielectric rough surface. The field within the coated object is modelled by FEM, while the coupling field between the object and rough surface is considered by BIM. The fields

ABSTRACT With the rapid development of industrial production and aerospace, how to measure the plasma density has also developed rapidly. So a radio-frequency plasma transducer based on a three-layer dielectric substrate antenna with a high dielectric constant is introduced. The top and bottom layers are dielectric plates, which protect the internal antenna structure and improve the equivalent permittivity

Polarization conversion of electromagnetic waves transmitted through multilayer nanoresonators, including a main homogeneous layer made of a transparent uniaxial dielectric sandwiched between epsilon-near-zero and metallic spacer layers, has been analytically modeled. The numerical analysis, based on exact solutions of electromagnetic boundary problems, confirms opportunities to use such multilayers

The paper deals with modelling of radiation from arbitrarily shaped thin wires above a multilayer and related engineering applications. The formulation is based on the set of corresponding Pocklington integro-differential equations (IDEs) for curved wires. The influence of lower layered half-space is taken into account by means of simplified reflection coefficient stemming from modified image theory

We propose a semi-analytical scheme for investigating the electromagnetic beam scattering by a uniaxially anisotropic chiral object. The scattered and internal fields are expanded in terms of appropriate spherical vector wave functions, and the method of moments procedure is employed for determining the unknown expansion coefficients. Normalized differential scattering cross sections are evaluated

An efficient moment-method algorithm for analyzing helix antenna is presented. This algorithm is developed based on solving the helix integral equations using two categories of continuous wavelets-like basis functions, Biorthogonal and Orthogonal wavelets. In the first part, the current in the helix antenna is obtained using the method of moments with the triangle basis and pulse testing functions

This paper presents a design investigation of the Electron Optical Gun (EOG) for a 42 GHz, 200 kW second harmonic gyrotron operating in the TE0, 3 mode. The initial design of MIG is done using established design equations and then optimized through numerical simulations. The different software, such as 2D-Numerical codes EGUN, TRAK and 3D-CST Particle Studio, are used to optimize the design and found

Sparse arrays play an important role in the widely used acoustic and electromagnetic applications such as sonar, radar, and satellite. In this paper, a recently proposed swarm intelligence algorithm, salp swarm algorithm (SSA), is introduced for design of both linear and planar sparse antenna arrays with optimum sidelobe level (SLL). The design of sparse antenna arrays can be regarded as a nonlinear

ABSTRACT In the last decade, it has been shown that short-range ultra-wideband (UWB) sensors can provide promising solutions to the issue of people localization in many interesting applications. The applicability of particular localization methods utilizing this wireless technology depends on the form of the motion of the monitored person. Therefore, great effort was initially taken to localize people

Federal Communications Commission (FCC) has released the regulation for medical body area network (MBAN) in 2012 as a BAN specialized for medical applications. MBAN is a narrowband BAN allocated on the 2360-2400 MHz frequency band. It is very promising, as it has the advantages of BAN modules like low power and high accuracy, which are essential parameters for medical applications. This paper provides

ABSTRACT A dual-band planar dipole antenna, incorporated with a zigzag-shaped dual-band artificial magnetic conductor with gain enhancement, is proposed here. By using 5×9 AMC surface as substrate to the dipole antenna, the bidirectional radiation pattern of the dipole antenna is transformed to unidirectional radiation pattern. The separation distance between the dipole antenna and the AMC surface

ABSTRACT We present the design, fabrication and experiment of a miniature nonresonant probe based on a coplanar waveguide dedicated to near-field imaging for electromagnetic compatibility applications. Our modeling approach, based on the Finite Difference Time Domain and Finite Element Method, proves that this probe is sensitive to the longitudinal component of the electric field. In addition to its

ABSTRACT Proceeding from the scattered field expansion in cylindrical harmonics, we define partial invisibility or partial cloaking as suppression of finitely many lowest-order field harmonics. We show that for benchmark structures (a dielectric rod and a perfectly conducting cylinder of circular cross section covered by a concentric dielectric layer), such multiple suppression can be achieved. For

The FDD method is normally used for the stability of the Tx and the Rx links in a fast-varying channel. It is required to physically separate the Tx and Rx arrays for independent Tx and Rx beam control. In this system, it is important to reduce the Tx self-interference (SI) that causes the problem of active element saturation and ADC dynamic range in the Rx beamformer. To suppress Tx SI, we proposed

This paper deals with a periphery surveillance system, which has been developed and deployed by CSIR-Central Institute of Mining and Fuel Research, Dhanbad, India as an aid for keeping constant vigilance on a selected area even in adverse weather conditions like foggy weather, rainy weather, dusty environment, etc. The developed system consists of a frequency modulated continuous wave radar with 400

This paper presents a robust optimization method to design patch antennas that consider uncertainties from the substrate electromagnetic properties and the manufacturing equipment. The robust optimization method is proposed to design an antenna that uses FR-4 as a substrate, addressing the uncertainties originated from the lack of standardization of this material properties and errors in the manufacturing

In the paper, the design and simulation of the TEM-TE10 wideband and high-power mode converter (MC) are investigated. The working frequency of the MC is in the frequency range of 4.3–8.8 GHz (68.7% bandwidth). Due to increasing the waveguide cross-section, the probability of the electrical breakdown dramatically reduces. Electrical breakdown may occur at very high-power outputs of the electromagnetic

The development of radar technology for the detection of small drones is getting attention of researchers. In this work, the detection of drones using Ku-band radar system has been discussed. We have utilized the advantage of nonlinear frequency modulation (NLFM) waveform for the suppression of range sidelobes. The performance and sensitivity of a radar system can be related with the linearity of system

In this paper, we propose a reflector antenna with a microstrip-patch-array offset feed. The proposed antenna offers several advantages in design flexibility, especially to determine the horizontal and vertical beam patterns by the modular feed and the reflector curvature design, respectively. Moreover, it provides an internal tuning mechanism in the form of a tuning strip which is relatively simple

An ultra-wideband metamaterial (MM) filter with steep cut-off is proposed at terahertz (THz) region. The filter is based on the flexible hybrid structure of copper (Cu)–polyimide (PI)–polymethacrylamide (PMI) multilayer, which reduces the mutual coupling in multilayer MMs. Simulation results prove that the central frequency of the filter is 125 GHz, while the square ratio reaches 0.92 and the relative

Branch-guide energy couplers can be used in the terahertz relativistic sheet electron beam traveling wave tubes (THz-RSBTWT) for high and high frequency microwave radiations. To analyze this type of coupler, a new method based on the phase superposition principle was put forward in this paper. A physical model was developed, which is applicable no matter the coupler width is large or small. The general

ABSTRACT In this article, substrate integrated waveguide (SIW) filter with compact size and wide out-of-band rejection is designed for 5G (sub-6 GHz) applications. To achieve the proposed filter responses, D-shaped resonators oriented face-to-face are etched out on the top layer of SIW. Due to the resonators loading, the filter provides a passband below the cut-off frequency of SIW. This decrease in

A new methodology to determine the loss tangent of dielectric planar samples by using electrically coupled resonators is presented. The coupling between the resonators is disrupted by the sample under test (SUT). The proposed methodology is based on the analysis of the equivalent circuit of the sensor in differential and common modes. This work demonstrates that the total quality factor of the electric

This paper proposes a novel subwavelength single-layer reflectarray antenna unit cell operating in X-band, composed of double hexagonal rings and a hexapole. This new cell is not sensitive to TE and TM polarizations. Infinite array approach has been used to determine the reflection phase curve. The proposed element has more than 575° linear phase range in 8.5–11 GHz frequency band by varying the radius

This paper develops an original circuit theory of energy and data transition. The modelling of signal and energy hybrid receiver (SEHR) is developed. The SEHR topology is described in function of the constituting coupled line (CL) and a transmission line (TL) performed with unfamiliar and arbitrary load values. The equivalent S-matrix versus electrical parameters is established. The analysis of the

The interaction of a stratified cylinder with an elliptically inhomogeneous plane wave is introduced and also determined through a rigorous theoretical approach. The scattered electromagnetic field by a multilayered cylinder is investigated through an application of the generalized Vector Cylinder Harmonics (VCH) expansion. The exact mathematical model to represent this scenario considers the so-called

ABSTRACT Small-sized gold nanoparticles (∼3nm) coated with Glutathione (GSH) ligand have designed as an active agent in photothermal therapy (PTT). GSH is pH-sensitive surface that have a fast response property to the variation in pH conditions, especially between normal (∼7.4) and cancer cell (6–6.5), that help the evaluation of the target and toxic effect of the cancer rather than normal cells. Results

Interaction between water and lubrication grease oil is not desirable, but it is not inevitable. The operational life of the machine component is influenced by humid grease oil. Metameterial-based transmission line sensor application is proposed and its operation is validated both numerically and experimentally by inserting grease oil samples in the sample holder. The proposed sensor structure is able

A novel approach of multiband real permittivity and permeability estimation of the magnetic composites using a modified under coupled multimodal (TE10p) substrate integrated waveguide (SIW) cavity is presented. The proposed schemes allow the accurate wideband microwave characterization of the magneto-dielectric composites by using the higher-order modes of the designed SIW cavity. The analytical closed-form

A circularly polarized (CP) scanning phased array antenna based on circular polarizer is proposed. An efficient technique is developed to introduce the novel scheme of the designed patch antenna and circular polarizer, which are coupled with a small gap. The new approach of fission transmission of electromagnetic (FTEM) wave is developed to transform linear-to-circularly polarized waves. The designed

ABSTRACT This study presents a new efficient alternative procedure for the assessment of the well-stirred (ws) condition of a mode-stirred reverberation chamber (RC) using newly developed coupling transfer gain functions. Coupling transfer voltage and current gain functions of the RC environment are developed from the ABCD parameters of the measured two-port S parameters in an RC. The proposed procedure

ABSTRACT An asymmetric coplanar waveguide fed frequency reconfigurable antenna based on composite right/left-handed transmission line is presented in this paper. The antenna is a composite right/left-handed transmission line composed of the meander line and a PIN diode. By controlling the switch of the PIN diode the antenna can change the frequency. Simulation and experimental results show that the

ABSTRACT In this study, a miniaturized Wilkinson Power Divider (WPD) has been designed. Central frequency of the passband for designed power divider (PD) is 1.55 GHz. Using the oval and rectangular- shaped resonators instead of each quarter-wavelength transmission lines of conventional Wilkinson power divider (CWPD) will result in reducing the size of proposed PD by 55%. Presented PD has many advantages

In this paper, a novel miniaturized triple-band planar monopole antenna combing single-cell metamaterial structure and defected ground plane is proposed. The miniaturization and triple-band characteristic of the antenna are achieved by loading the designed multiresonant metamaterial unit cell. Furthermore, a compact annular defected ground structure is proposed and used to improve the bandwidth of

ABSTRACT An engineered silicon rib waveguide on Silicon-On-Insulator platform which can act as virtual photonic bandgap structure is proposed. Selective periodic etching of materials from a rib waveguide is done to create a periodic rib-ridge structure. Each of the rib-ridge sections will therefore have different effective refractive indices and will act as virtual multilayered periodic structure or