Dielectric Plate Research Articles

Supersonic flutter characteristics of dielectric rectangular plate: The effects of magneto-aero-hydrodynamic interactions

This paper offers the authors’ views on critical magneto-aeroelastic behavior for dielectric rectangular isotropic plates. Magneto-aeroelastic stability and dynamic models are used to determine the total perturbed pressure caused by the incident flow of a perfectly conducting supersonic gas and a magnetic field as well as the critical flutter speed of flowing stream. The analytical description presented here is a generalization of the well-known pressure’s formula obtained on the basis of the “piston theory” of the classical theory of gas dynamics in the case of a magneto-hydrodynamic flow of elastic plates. Along with the analytical solutions, parametric studies are supplied to inform the reader about the influence of magnetic field on the flutter boundary.

A compound Kinoform/Fresnel zone plate lens with 15 nm resolution and high efficiency in soft x-ray

X-ray microscope as an important nanoprobing tool plays a prevailing role in nano-inspections of materials. Despite the fast advances of high resolution focusing/imaging reported, the efficiency of existing high-resolution zone plates is mostly around 5% in soft x-ray and rapidly goes down to 1%–2% when the resolution approaches 10 nm. It is well known that the rectangular zone shape, beamstop, limited height/width ratios, material absorption of light and structural defects are likely responsible for the limited efficiency. Although zone plates with Kinoform profile are supposed to be efficient, progress for achieving both high resolution (<30 nm) and high efficiency (>5%) have hardly been addressed in soft x-ray. In this work, we propose a compound Kinoform/Fresnel zone plate (CKZP) by combing a dielectric Kinoform zone plate with a 15 nm resolution zone plate. Greyscale electron beam lithography was applied to form the 3D Kinoform zone plate and atomic layer deposition was carried out to form the binary zone plate. Optical characterizations demonstrated 15 nm resolution focusing/imaging with over 7.8% efficiency in soft x-ray. The origin of the efficiency improvement behind the proposed compound lens is theoretically analyzed and discussed.

Coaxial Beam Rotating HPM Mode Converter Using Dielectrics Plates

The incorporation of the dielectric plates to produce phase delay for propagating waves is a widely employed technique in phase shifters and mode converters. In this article, a compact dielectric plate loaded coaxial beam rotating (CBR) mode converter having high gain and co-polarized (CP) pattern has been proposed for high-power microwave (HPM) applications at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${X}$ </tex-math></inline-formula> -band. Here, the input transverse magnetic (TM), i.e., TM01 mode, is converted to CP transverse electric (TE), i.e., TE11 likeness mode. The proposed design consists of a circular waveguide (WG) loaded with 12 dielectric polytetrafluoroethylene (PTFE) plates in a radial-azimuthal direction. For 5-mm plate thickness, the proposed design yielded a reflection loss of −20.01 dB with a radiation efficiency of 98.34% and a 17.9 dB gain at 10.084 GHz. Also, the power handling capacity of the proposed structure is predicted as 3.20 GW. Furthermore, the mode conversion is verified by measuring the far-field radiation pattern. Besides, the simulation studies of the thermal behavior of the proposed design are also discussed with the aid of CST Studio Suite.

Study on the plasma characteristics in a needle-plate dielectric barrier discharge with a rotating dielectric plate

The enhancement of plasma generation in atmospheric pressure dielectric barrier discharge (DBD) is gaining increasing interest for various plasma applications. In this paper, the effect of surface charges moving with the rotating dielectric plate on improving the generation of streamer channels is investigated by a statistical analysis of electrical measurements, optical diagnostics, and numerical simulation in a needle-plate DBD device with a rotating dielectric plate. Results suggest that rotating the dielectric plate can improve the spatiotemporal distribution of streamer channels by inducing a bending of the streamer channels and an increase in the number of discharges. Statistical results show that the number of current pulse and discharge energy are increased by 20% and 47%, respectively, at the rotating speed of 160 rps (revolution per second). Based on the interaction between the applied electric field and the electric field induced by surface charges, a formula is proposed to govern the effect of rotating the dielectric plate on the discharge energy and streamer bending. To further understand the mechanism of the influence of rotating the dielectric plate on plasma properties, a 2D fluid model is implemented, and the reduced electric field and streamer propagation are analyzed. Results show that the effective transfer and reuse of surface charges play an important role in the enhancement of plasma generation.

High-efficiency focusing and imaging by dielectric kinoform zone plate lenses with soft X-rays.

With fast advances in enhancing the focusing/imaging resolution of Fresnel zone plate lenses toward sub-10 nm, low diffraction efficiency in connection with their rectangular zone shape still remains a big issue in both soft and hard X-ray microscopy. In hard X-ray optics, encouraging progress has recently been reported in our earlier attempts of high focusing efficiency by 3D kinoform shaped metallic zone plates, formed by greyscale electron beam lithography. This paper addresses our efforts towards high focusing/imaging efficiency by developing a novel dielectric kinoform zone plate lens for soft X-rays. The effects of the zone materials and zone shapes on the focusing/imaging quality were first theoretically investigated by a modified thin-grating-approximation method, revealing superior efficiencies of dielectric kinoform zone plates over rectangular ones in metals. Optical characterizations of replicated dielectric kinoform zone plates by greyscale electron beam lithography demonstrate a focusing efficiency of 15.5% with a resolution of 110 nm in the water window of X-rays. Apart from high efficiency, the novel kinoform zone plate lenses developed in this work exhibit significant advantages over conventional zone plates, i.e. simplified process, low cost and no need for a beamstop.

Influence of Dielectric Plate Parameters on the Reflection Coefficient of a Planar Aperture Antenna

In this article, an aperture antenna excited by a waveguide with a circular cross-section and covered with a dielectric plate was analyzed via simulation calculation and verified via measurements. The influence of the geometrical and electromagnetic parameters of the dielectric plate on the reflection coefficient S11 of the antenna opening was systematically analyzed. The geometrical parameters taken in this analysis are the thickness d and the width/length h1/h2 of the dielectric plate. The electromagnetic parameters used in this analysis are the real and the imaginary part of permittivity (εr, tan δ) and the electrical conductivity of the dielectric plate (σ). The simulation calculation and analysis included other structural and electromagnetic parameters of the dielectric plate (density of the radome material, relative permeability, and magnetic loss tangent (ρ, µr, and tan δµ, respectively)), but the results show that in the range of real values of these parameters for the materials used for the dielectric plate, they had no significant influence on the reflection coefficient. The results show that impedance-matched antennas with very low values of the reflection coefficients S11 at the resonant frequency can be realized by changing the geometrical and electromagnetic parameters of the dielectric plate material. The results are presented for a circular aperture antenna on a planar grounded plane with a dielectric plate on the opening, and the achieved lowest values of the S11 parameter were −45.17 dB (simulated) and −43.93 dB (measured) at the frequencies of 1.7820 GHz and 1.7550 GHz, respectively. The estimated values of the dielectric plate parameters in this case are thickness d = 11.08 mm (0.67 λ); width × length of grounded plane and dielectric plate h1 × h2 = 423 × 450 mm2 (2.51 × 2.67 λ); relative permittivity 2.5, tan δ = 0.09, μr = 1, tan δμ = 0.00, ρ = 1200 kg·m−3; and electrical conductivity σ = 0 S/m. The simulation calculation results were verified by measuring the reflection coefficient S11 on the created laboratory model of the aperture antenna with the dielectric plate and showed a very good match.

Axionic and nonaxionic electrodynamics in plane and circular geometry

Various aspects of axion electrodynamics in the presence of a homogeneous and isotropic dielectric medium are discussed. First, we consider the ``antenna-like'' property of a planar dielectric surface in axion electrodynamics, elaborating on the treatment given earlier on this topic by Millar et al. [J. Cosmol. Astropart. Phys. 01 (2017) 061.]. We calculate the electromagnetic energy transmission coefficient for a dielectric plate, and compare with the conventional expression in ordinary electrodynamics. Second, we consider the situation where the medium exterior to the plate, assumed elastic, is ``bent back'' and glued together, so that we obtain a circular dielectric string in which the waves can propagate clockwise or counterclockwise. As will be shown, a stationary wave pattern is permitted by the formalism, and we show how the amplitudes for the two counterpropagating waves can be found. Third, as a special case, by omitting axions for a moment, we analyze the Casimir effect for the string, showing its similarity as well as its difference from the Casimir effect of a scalar field for a piecewise uniform string [I. Brevik and H. B. Nielsen, Phys. Rev. D 41, 1185 (1990).]. Finally, including axions again we analyze the enhancement of the surface-generated electromagnetic radiation near the center of a cylindrical haloscope, where the interior region is a vacuum and the exterior region a high refractive index medium. This enhancement is caused by the curvature of the boundary, and is mathematically a consequence of the behavior of the Hankel function of the second kind for small arguments. A simple estimate shows that enhancement may be quite significant, and can therefore be of experimental interest. The presence of an absorber in the center and the possibility of adopting it to search for axions with mass in the THz region, and possibly the GHz region too, is also discussed. This proposal is suggested as an alternative to the reflector arrangement in a similar arrangement recently discussed by Liu et al. [, Phys. Rev. Lett. 128, 131801 (2022).].

Ultrathin Acoustic Holography

AbstractHow to realize acoustic holography via ultradeep‐subwavelength structures is a challenging problem in the past decades, which is thought impossible due to the linear proportional relationship between the structural thickness and acoustic wavelength. In this article, the methodology of ultrathin holography by patterning holes in an acoustic insulation plate with an ultradeep‐subwavelength thickness is introduced. The transmitted sound field can be manipulated arbitrarily to form a desired shape by designing the ultrathin pattern based on the nonlocal wave interaction theory. The physical mechanism of the nonlocal behavior to achieve a sophisticated hologram is revealed due to the interaction among the sound wave components themselves. Furthermore, the experiments are designed to map out the pressure amplitude field of a “sun” pattern in air and water, respectively. The work demonstrates the advantage of nonlocal ultrathin holography in the applications of ultrathin acoustic devices and provides inspiration for the holographic wave manipulation.

Design and Experiments of a Beam-Steerable Wideband Reflectarray Antenna for High-Power Microwave Applications

A beam-steerable wideband reflectarray antenna (WRA) is presented in this communication. The WRA element operated at 3.3–5.5 GHz (relative bandwidth 50%) exhibits a continuous 360° phase coverage, and its power handling capacity (PHC) is estimated to exceed 4.5 GW/m2 in simulation, indicating its potential in high-power microwave (HPM) applications. Moreover, to verify the wideband performance of the WRA, a prototype was successfully designed, simulated, fabricated, and measured in the S- and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$C$ </tex-math></inline-formula> -bands. The WRA prototype is composed of an ultrawideband helical feed antenna, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$25\times25$ </tex-math></inline-formula> antenna elements, and a dielectric plate as a radome. The results show that in the frequency band of 3.3–5.5 GHz, the WRA can achieve an arbitrary direction of reflection beam within ±60° (120° conical region). Additionally, at the center frequency of 4.4 GHz, its sidelobe level is consistently below −15 dB, while the maximum gain loss is 3.3 dB during beam steering, and the maximum aperture efficiency reaches 67.89% in the direction of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\theta _{0}=0$ </tex-math></inline-formula> ° and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\varphi _{0}=0$ </tex-math></inline-formula> °.

Peculiarities of Resonant Absorption of Electromagnetic Signals in Multilayer Bolometric Sensors.

We examine the effect of resonant absorption of electromagnetic signals in a silicon semiconductor plasma layer when the dielectric plate is placed behind it both experimentally and numerically. It is shown that such plate acts as a dielectric resonator and can significantly increase the electromagnetic energy absorption in the semiconductor for certain frequencies determined by the dielectric plate parameters. Numerical modelling of the effect is performed under the conditions of conducted experiment. The numerical results are found to be in qualitative agreement with experimental ones. This study confirms the proposed earlier method of increasing the efficiency of bolometric-type detectors of electromagnetic radiation.

ПОЛЯРИЗАТОР НА СЕКТОРНОМУ ХВИЛЕВОДІ, ЧАСТКОВО ЗАПОВНЕНОМУ ДІЕЛЕКТРИКОМ

In the article a polarizer based on a sector waveguide partially filled by dielectric is studied. The design of a polarizer based on a sector waveguide with smaller dimensions of the dielectric plate and a better coefficient of the standing wave rectangular waveguide - polarizer on sector waveguide - rectangular waveguide junction compared with rectangular waveguide-polarizer based on a circular waveguide -rectangular waveguide junction has been developed. The diagrams of the articulateon of the waveguide segments of the antenna-feeder path on rectangular waveguides with a polarizer on a sector waveguide and with a polarizer on a circular waveguide are shown. Formulas for the propagation constant of a sector waveguide partially filled with a dielectric and the effective permittivity of a sector waveguide are given. The dependences of the relative permittivities of a waveguide with a sector dielectric plate parallel and perpendicular to the plane of polarization of the incident wave on the average thickness of the sector dielectric plate are presented. The paper analyzes a sector waveguide partially filled with a dielectric, which has휃=휋/3 и 훷=휋/6. In this case, the scalar eigenfunction of the sector waveguide for the quasi-퐻ଷଵ wave is used. The corresponding dependences of the change in the differential phase shift in the considered wave range on the average thickness of the sector plate are presented. At small thicknesses of the phasing plates the decrease in the polarizer broadband is due to an increase in the phase shift in the long-wavelength part of the range and at large thicknesses in the short-wavelength one. By choosing the permittivity of the material, it is possible to increase the broadband of the polarizer at the expense of some increase in the length of the plate. The dependence of the standing wave coefficient of the junction rectangular waveguide - polarizer - rectangular waveguide on the value 휆/휆଴. The standing wave coefficient for the junction of rectangular waveguide - polarizer on a sector waveguide - rectangular waveguide is 3...5 % less than for a junction of rectangular waveguide - polarizer on a circular waveguide - rectangular waveguide. A polarizer based on a sector waveguide with a dielectric plate has an advantage over a polarizer based on a circular waveguide with a dielectric plate when building antenna-feeder paths on rectangular waveguides. This advantage consists in achieving a lower value of the standing wave coefficient on the waveguide section of the path with a polarizer and a shorter length of the dielectric plate – 1,25휆଴.

Inactivation efficacy of low-pressure plasma treatment against seed-borne tomato pathogen Clavibacter michiganensis and effect of seed setting position and mesh sheet usage.

Clavibacter michiganensis, a gram-positive actinomycete, is a major seed-borne tomato pathogen. We investigated the inactivation efficacy of low-pressure plasma treatment against C. michiganensis inoculated on tomato seeds by placing them on a mesh sheet above the bottom dielectric glass plate. The 2- and 5-minute plasma treatment reduced C. michiganensis populations on the tomato seeds by 0.8 and 1.8 log cfu/seed, respectively. The reduction rates were similar to those of C. michiganensis on shirona (cruciferous) seeds, which have different shapes and surface structures. In contrast, the inactivation of C. michiganensis cells using plasma was more difficult than that of X. campestris cells. Additionally, it was found that placing seeds on a mesh sheet laid on the dielectric glass plate was remarkably effective in inactivating the pathogens on tomato seeds. Since the tomato seeds were susceptible to damage from plasma treatment, methods to reduce its damage need to be investigated.

Sliding Interaction of Accelerated Proton Beams with Curved Dielectric Surface

Sliding Interaction of Accelerated Proton Beams with Curved Dielectric Surface

220 GHz High-Gain Substrate Integrated Antennas With Low Fabrication Cost Based on Higher Order Mode and PCB Technology

In millimeter-wave (MMW) and terahertz (THz) bands, the operation frequency is high and there are challenges in fabrication and microassembly processes, bringing high-accuracy requirements and high manufacturing cost. In this article, high-gain substrate integrated antennas with low fabrication cost are presented for MMW/THz applications. The basic antenna consists of two parallel TE201 resonant cavities and is directly fed by a grounded coplanar waveguide (GCPW). Radiation slot apertures are modified to increase aperture radiation efficiency and improve radiation patterns and gain. The antenna scheme is analyzed and a 220 GHz <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times2$ </tex-math></inline-formula> slot array antenna is developed as an example. To further improve the antenna gain with low fabrication cost and low feeding network loss, the basic antenna is explored to feed a modified dielectric plate lens. The high-gain scheme and design flowchart are provided. Both basic and improved structures are fabricated by normal single-layer printed circuit board (PCB) technology and high antenna gains are achieved. The measured peak gain of the basic antenna and the antenna with dielectric plate lens are 13.5 and 20.2 dBi, respectively. The measured return losses are better than 10 dB from 192 to 247 GHz. The antennas have advantages of simple antenna feeding structure, low fabrication cost, wide bandwidth, and high gain.

Numerical study on uniformity of atmospheric helium gas dielectric barrier discharge on non-smooth surface regulated by sinusoidal clipping voltage

In practical applications of dielectric barrier discharges under atmospheric pressure, plasma usually acts on non-smooth surfaces. The electric field distortion and uneven surface charge distribution caused by its surface morphology will create an adverse effect on the uniformity and stability of the discharge. In this paper, we establish a simulation model of atmospheric pressure helium dielectric barrier discharge on a wavy lower dielectric plate, and use a sinusoidal clipping voltage to regulate the discharge uniformity. The results show that the discharge uniformity is improved compared with the unclipped case, and the discharge mode is changed from columnar mode to quasi-uniform mode. This can be attributed to the incomplete discharge dissipation caused by the reduction of air gap voltage; the subsequent electron backflow process neutralizes the the residual space electrons with the surface charge, which limits the accumulation of surface charges. With the increase of clipping ratio, the surface charge distribution becomes more uniform, and the radial fluctuation of electric field distribution weakens. In addition, the discharge efficiency is improved in a certain clipping range. This study reveals the mechanism of clipping voltage influence on non-smooth surface discharge, and provides a new idea for regulating the uniformity of dielectric barrier discharge.

Recycled EPS insulation plates: critical factors and potentialities for the productive feasibility of a venture in the District of La Plata

Previous research has allowed developing and characterizing an expanded polystyrene waste (EPS) based insulation material that can be used to manufacture plates, providing job opportunities to unemployed or vulnerable social groups. By working together with a local recycling cooperative, the production processes needed for their manufacture on a scale suitable for commercialization were determined. The goal of this research is to analyze these production processes and identify the critical aspects that make the technology’s implementation and management viable. The methodology used involves i. the product’s adaptation; ii. determining supplies and resources for its feasibility; iii. detecting the most critical production processes; and, iv. adapting to the particular case of application. A set of minimum requirements is obtained to develop a productive venture. In addition, the most critical processes related to the separation and obtaining of the EPS and its continuous supply over time, are identified. The results summarize contributions to replicate and make this experience sustainable.

THERMOELECTRIC POWER GENERATION FROM WASTE HEAT OF GAS STOVE BY USING THE THERMOELECTRIC GENERATOR

The objective of this research is set to produce energy by utilizing the unused heat of gas stove through thermoelectric generator. Currently, an increasing concern of environmental issues of emissions like greenhouse effects and the scarcity of fossil fuel has resulted in extensive research into the alternative ways of generating electrical power. Thermoelectric power generator has been considering as one of the promising alternatives due to its advantages. The application of this alternative option in converting waste-heat energy directly into electrical power that may also enhance the overall efficiencies of energy conversion systems. In this study, a gas burner was set to generate electricity that will produce waste heat. One thermoelectric unit is installed underneath the burner cap of the gas burner. Gas flame at the edge of the burner cap creates heat sources (hot side) for the thermoelectric unit. A gas-mixing chamber underneath the thermoelectric unit functions as heat sink (cold side) for the thermoelectric unit. An insulation plate is inserted in between the thermoelectric unit and the burner cap to control the hot side temperature. The thermoelectric unit generates electricity while the gas burner is in use and the flame heats up the burner cap. The thermoelectric unit connects to an electric circuit and provides electricity to power devices.

Mathematical Model of the On-Board Antenna of Reentry Spacecraft Taking into Account Surface Waves

Introduction. The onboard antennas of the returned hypersonic aircraft are weakly directional, which is achieved by radiation from the open end of the waveguide. When passing through dense layers of the atmosphere, they are exposed to aerodynamic heating, for protection from which a heat-resistant radio-transparent thermal protection is used. The case of uniform thermal protection of the antenna can be interpreted as the absence of heating or heating uniform in the thickness of the thermal protection.Aim. The problem of obtaining an analytical description of the radiation characteristics of a circular waveguide closed by a flat homogeneous dielectric plate is solved. Since in such a formulation it is necessary to consider the resonant domain, a strict solution of Maxwell's equations is required.Materials and methods. Of the known analytical methods of solution, it is possible to use the method of integral transformations and the method of eigen functions. Both of these methods are used in the work. In this case, the assumption is used that the electrical parameters of the dielectric plate (thermal protection) and the geometric dimensions do not depend on time.Results. The relations describing the directional pattern of a circular waveguide with dielectric thermal protection and taking into account the electrical parameters of thermal protection and its thickness are obtained. Expressions are also obtained for the fields of lateral, surface and outflow waves, from which it is possible to calculate the power output by these fields. Relations for the separation of singular points of integrand expressions into poles corresponding to surface, outflow and lateral waves are obtained. Surface, outflow and lateral waves can have a certain effect on the radiation pattern. To determine this conclusion, analytical relations are obtained for determining the poles of integrand expressions that fully describe surface, outflow and side waves. All the analytical results obtained correspond to Numerical calculations were carried out on some of the obtained ratios.Conclusion. The results showed that the power of the side waves is zero. It also follows from the calculations carried out that there is no radiation field of surface and outgoing waves, i.e. there is no contribution of them to the radiation pattern.

Thermal Rehabilitation of Facades of Operated Panel Buildings

Field studies of panel buildings have shown that after 30 years of operation, the technical condition of structural elements (embedded parts, welds, etc.) are in working condition. At the same time, the thermal characteristics of the external wall fencing have decreased by more than 30 % compared to those adopted during the design and do not meet regulatory requirements. One of the main reasons for this is the destruction of the material of the thermal insulation layer of wall panels under the influence of atmospheric influences. Consequently, the thermal rehabilitation of external wall panels allows for further operation of panel buildings without restrictions. According to the results of the studies carried out, it is proposed to use a factory-made thermal insulation cladding plate for thermal rehabilitation of the facades of operated panel buildings. The publication presents the results of laboratory studies on the choice of an effective solution for the design of the conection (joint) of individual thermal insulation plate into a thermal insulation facing plate of the required dimensions. The technology of manufacturing thermal insulation facing plates is described. The main advantages of the proposed structural and technological solution for the thermal rehabilitation of external wall panels are: a significant reduction in manual technological processes on the construction site; the possibility of performing work without eviction of residents; eliminating the appearance of cold bridges in the inter-panel seams during the operation of buildings through the use of a folding type joint.

Broadband Circularly Polarized Conical Corrugated Horn Antenna Using a Dielectric Circular Polarizer.

In this paper, a broadband left-handed circularly polarized (LHCP) corrugated horn antenna using a dielectric circular polarizer is proposed. Circularly polarized (CP) waves are generated by inserting an improved dovetail-shaped dielectric plate into the circular waveguide. Compared with the traditional dovetail-shaped circular polarizer, the proposed improved dovetail-shaped circular polarizer has a wider impedance bandwidth and 3 dB axial ratio bandwidth. A substrate-integrated waveguide (SIW) structure is designed as a wall to eliminate the influence of fixed grooves on the circular polarizer. The simulated reflection coefficient of the dielectric plate circular polarizer is less than -20 dB in the frequency band from 17.57 to 33.25 GHz. Then, a conical corrugated horn antenna with five corrugations and a four-level metal stepped rectangular-circular waveguide converter are designed and optimized. The simulated -10 dB impedance and 3 dB axial ratio (AR) bandwidths of the circularly polarized horn antenna integrated with the polarizer are 61% (17.1-32.8 GHz) and 60.9% (17.76-33.32 GHz), respectively. The simulated peak gain is 17.34 dBic. The measured -10 dB impedance is 52.7% (17.2-27.5 GHz).