Search

The primary objective of this paper is to conduct a comparative analysis of diverse Electromagnetic Band Gap (EBG) antennas in terms of their suitability for Wi-Fi applications operating at 5 GHz. Wi-Fi primarily operates within the 2.4 GHz and 5 GHz frequency bands, with the 5 GHz band offering higher data rates and reduced interference compared to the 2.4 GHz band. Furthermore, its larger number of available channels makes it an optimal choice for environments with high user density. The antennas in this study are designed with dimensions of 28.11x32.40x1.6 mm³ (length x width x height) using RT/Duroid 5880 substrate, which has a thickness of 1.6 mm and a relative permittivity (εr) of 2.2. The integration of Electromagnetic Band Gap structures in antenna designs has gained substantial attention due to their unique properties that enhance antenna performance characteristics. The paper presents sixteen distinct EBG antennas, all designed using CST software. These antennas incorporate various EBG shapes, such as Fork, L-shape, C-shape, Hash, and Z-shape, positioned on a rectangular patch and in the ground plane. The study's results reveal that the Hash EBG on the patch offers superior performance compared to other EBG types. As a result, the Hash EBG on the patch, alongside various Z-shaped EBGs on the ground plane, is assessed for different antenna performance parameters, including return loss, radiation patterns, and gain. Finally, a diagonal Z-shaped EBG antenna is designed, simulated, and tested. The antenna return loss at 5.2GHz is –48 dB The proposed antenna achieved a peak gain of 7.3 dB at 5.2GHz. The proposed antenna exhibits omnidirectional properties. The antenna shows an efficiency of 90% at the resonant frequency. The experimentally measured results of the designed diagonal EBG antenna have shown satisfactory agreement and are consistent with the simulated results. The findings of this research contribute to a better understanding of EBG antennas potential for Wi-Fi applications in the 5 GHz frequency band. [ABSTRACT FROM AUTHOR]

This paper presents a wideband, thin-profile and enhanced-gain microstrip patch antenna improved by using a novel mushroom-like Electromagnetic Band Gap (EBG) structure and forming periodic Defected Ground Structures (DGS) on the ground plane. The proposed antenna operates between 9.56 and 14 GHz and has 4.44 GHz–10 dB impedance bandwidth. With A4, the gain of the reference antenna is increased by 64.4%, while a 38% bandwidth is also achieved. The parametric analyses carried out on the metallic part area of the novel EBG patch indicated that when the area of the used EBG patches are approximately three quarters or less of the conventional ones, greater gain values for the designed antenna are obtained. This relation between the EBG patches and the antenna gain can be pointed out as the novelty of the study. The results were analysed by the simulations carried out with CST Microwave Studio and were verified by measurements from manufactured prototypes. [ABSTRACT FROM AUTHOR]

The dense establishment of the Wi‐Fi devices creates an opportunity to map the surrounding environment using Wi‐Fi signals as sounding waveforms. Recently, the Channel State Information (CSI) measurement analysis from Wi‐Fi networks has been widely used for detecting and possibly tracking the presence of obstacles between a transmitter and a receiver. According to the IEEE 802.11bf Task Group, Wi‐Fi sensing will utilize a band between 5.925 and 7.125 GHz, making the CSI measurement finer‐grained with the additional large bandwidth. In this paper, a wideband compact antenna is designed targeting the 5.9–7.1 GHz band based on the slot‐loading technique. Later, a wideband multiple‐input multiple‐output (MIMO) antenna is designed using defected ground structures, protruded ground, and electromagnetic band gap structures for isolation improvement, and the measured isolation shows 30–45 dB between the elements in the operating frequency range. The envelope correlation coefficient is less than 0.001 with the diversity gain being nearly 10. The fabricated single antenna has a compactness of 0.3λ0 ${\lambda }_{0}$ in both dimensions (14 mm × $\times $ 14 mm), measured bandwidth of 1.55 GHz (5.95–7.5 GHz) with a peak gain of 2.2 dBi at 6.8 GHz, and 90% efficiency in the operating frequency range whereas the wideband MIMO antenna has a size of 14 mm × $\times $ 37 mm with 0.5λ0 ${\lambda }_{0}$ spacing between the elements. [ABSTRACT FROM AUTHOR]

In this paper, design and realisation of a low profile Archimedean spiral antenna is presented. The low profile Archimedean spiral antenna is printed on a substrate and backed by a reflector consisting of DGS. The DGS unit cell consists of a parallel combination of meander line inductors and inter-digital capacitors. This, DGS is one of the forms of electromagnetic band gap (EBG) structures providing electromagnetic band gap characteristics. It is used as a reflector with spiral antenna to achieve unidirectional radiation properties and a low profile of antenna. A modified version of uniplanar EBG cell is used as a DGS cell. This cell is used for configuration of the DGS ground plane. This ground plane is evaluated for its electrical characteristics and used as a reflector for the spiral antenna. Archimedean Spiral antenna is designed and simulated in the frequency band of 1-6GHz with DGS as a reflector. The antenna characteristics are studied for physical parameters of the antenna. These parameters are optimized for better electrical characteristics. The performance of the proposed antenna is also compared with conventional metallic (PEC) reflectors. Simulated results of an antenna are validated by measurement. Antenna height reduction of 60 % is achieved compared to conventional cavity-backed spiral antennas. [ABSTRACT FROM AUTHOR]

A co-planar waveguide (CPW)-fed dual-band circularly-polarized (CP) disc-shaped monopole antenna with an electromagnetic band gap (EBG) array is presented for Wi-MAX, WLAN, and ISM band applications. The proposed monopole antenna is comprised of an arc-shaped stub (in the middle), a C-shaped strip (on the left), and an inverted L-shaped strip (in the right). The circular polarization is produced by truncating an arc in the T-shaped radiator, and the antenna is placed over an EBG array to achieve broader impedance and axial ratio bandwidths. The impedance bandwidth and axial ratio bandwidth (ARBW) in the first resonating band are 36.73% (2–2.9 GHz) and 21.16% (2.24–2.77 GHz), respectively. The antenna covers (2.4–2.48 GHz) WLAN/ISM band, (2.5–2.69 GHz) Wi-MAX band, and (2.38–2.49 GHz) Bluetooth application. The impedance bandwidth in the second resonating band is 6% (5.65–6 GHz), which covers (5.72–5.87 GHz) ISM band and (5.72–5.85 GHz) WLAN band. The CPW-fed disc-shaped antenna with an EBG array has dual band radiation characteristics, improved gain and radiation efficiency, compact size, and simple, light weight, and easy design with no vias required. The radiation characteristics of the proposed antenna are measured, and they agree well with the simulated results. [ABSTRACT FROM AUTHOR]

Electromagnetic noise (EMI) affects efficiency of a gadget, proximity devices and human beings, necessitating the noise mitigation. Introduction of Electromagnetic Band Gap (EBG) structure in PCB as plane pairs helps for high-speed operations. In this paper, the planar L-bridge embedded pattern-type EBG structure is designed to mitigate the noise. Experimental verification of the designed EBG type with various geometrical parameters is carried out by altering the geometrical parameters of the unit cell with 18 cases. All the cases are simulated for the frequency sweep 0.1–10 GHz. Simulation results are compared with theoretical calculations and measurement results. It is found that they are in good agreement. The depth in noise levels can be efficiently altered by changing air gap, line length and unit cell width. In order to validate the EBG, a continuous plane is considered and found that EBG helps to mitigate the noise level in the higher frequency. [ABSTRACT FROM AUTHOR]

Copyright of Journal de Ciencia e Ingeniería is the property of Corporacion Universitaria Autonoma del Cauca and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: A discussion of using an ultrawide band (UWB) Hilbert‐shaped metamaterial (MTM) antenna structure for RF energy harvesting is exemplified in this article to conduct the use of organic substrates. Therefore, the proposed design is structured as a low profile rectangular MTM array in the context of wearable systems. The antenna is mounted on a prepared indium‐nickel oxide‐based polymerized Palm fiber (INP) substrate and backed with a ground plane of square electromagnetic band gap (EBG) defects. Fifteen samples of INP substrate are prepared for this study. Thus, the prepared INP substrates characterizations are tested using a T‐resonator transmission line technique printed on an FR4 substrate. In this technique, the measured scattering parameters are interpreted from two resonators with two different characteristics impedance to be employed for retrieving the relative permittivity (εr) and permeability (μr). This process is included to ensure the prepared substrate properties controllability for microwave devices manufacturing. After that, the proposed antenna is manufactured from silver nanoparticle (SNP) printout. The performance of the proposed antenna is tested numerically and experimentally. It is found that the proposed antenna shows an UWB response to start from 3 and up to 10 GHz that suits different applications including IoT, 5G, and WiMAX system networks. The measured gain spectrum shows four peaks at 3.5, 4.2, 5.4, and 6 GHz with gain values of 1.1, 2, 3.4, and 3.9 dBi, respectively. Finally, the conversion efficiency of RF harvesting is measured experimentally for the antenna in case of flat profile and bended structure at the frequency bands of interest to reveal insignificant changes. [ABSTRACT FROM AUTHOR]

A low-profile multiple-input/multiple-output (MIMO) antenna of dimension 0.5 λ 0 × 0.7 λ 0 is proposed in this communication. This antenna consists of four square radiating patches and a partial ground to which a fractal H-shaped metamaterial electromagnetic band gap (MM-EBG) isolator is etched below the substrate in between the gaps of adjacent pairs of radiating patches or on each arm of intersection of the antenna. The isolator structure is simple to design and is capable of reducing mutual coupling by 15 dB, 16 dB, and 9 dB between antenna elements 1 & 2, 1 & 3, and 1 & 4, respectively. Favorable performance in terms of envelope correlation coefficient (less than 0.1, 0.05, and 0.1) and diversity gain (greater than 9.96, 9.98, and 9.93 dB) with consistent frequency band ranging from 2.53 GHz to 7.3 GHz is exhibited by the proposed MIMO antenna. The results are compared with previous reported literature, and comparative results shows good performance in terms of bandwidth, ECC, diversity gain, and radiation characteristics with improved isolation. Also, an equivalent circuit model of proposed design is presented. The simulated design is validated by fabricating and testing. The measurement of performance parameters closely agree with the simulated ones and have the potential for S and C band applications such as WLAN, WiMAX, IoT, and 5G. [ABSTRACT FROM AUTHOR]

Electromagnetic band gap (EBG) based two ports multiple‐input and multiple‐output (MIMO) substrate integrated waveguide (SIW) antenna for two quadrant beamforming applications using metasurfaces (MS) is addressed. A novel SIW structure is employed to achieve beamforming. This work comprises two types of vias having different diameters and lengths in order to achieve multibeam in the first and second quadrant with 120° coverage. Two cross slots tilted at ±45° are etched on top of the structure. The width variation of one of the cross slots achieved beam scanning in first quadrant with coverage of 90°. Additionally, four circular slots are etched on the top metallic layer to improve the axial ratio and the gain of the antenna. Apart from that, two diagonally etched slots help to enhance the gain and radiation properties of the antenna. Furthermore, to get the good mutual coupling and isolation between the two ports, EBG unit cells are deployed on the ground. The proposed antenna shows good right hand circularly polarized radiation within the band with the help of MS deployed on an extended part of the substrate. MS also improves the return loss bandwidth. In the end, the diversity properties of the MIMO have been studied as well. The proposed antenna shows good performance in all respects for 5G applications. [ABSTRACT FROM AUTHOR]

This paper proposes the design of three compact antennas for WiMAX, WLAN and ISM band applications. Antenna 1 consists of a monopole radiating element with an electromagnetic band gap (EBG) structured ground. By employing the EBG structure, an ultra-wide band frequency of 2.4–4.8 GHz (66.66%) is achieved. Antenna 2 is configured with an electric-LC (ELC) element, which achieved an ultra-wide band (UWB) frequency of 2.38–4.91 GHz (69.41%). Antenna 3 is integrated with ELC and EBG together, in which a UWB frequency of 2.3–5.3 GHz (78.94%) is obtained with improved impedance matching. The three antennas have omnidirectional radiation patterns which cover the ISM band at 2.4 GHz and WiMAX at 2.5/3.5 GHz over the operating bands. The radiation efficiency is > 75% throughout the operating bands of all the antennas. In addition to the WiMAX and ISM bands, antenna 3 covers WLAN in the 5.2 GHz band. The proposed design can be applied to wireless mobile communication systems, which have the advantage of ease of fabrication and compactness. [ABSTRACT FROM AUTHOR]

In this paper, an electromagnetic band gap structure with fractal geometry based on Peano curves is proposed to suppression of degenerated modes. The geometry is characterized by the inclusion of air slots into the substrate, under the feed line, of a rectangular microstrip patch antenna. The parameters analyzed are the input impedance using the Smith chart, the reflection coefficient (S11), radiation diagram and the electric field distribution of the propagation modes. The simulated results were compared with the measured results, obtained from manufactured prototypes and show that the proposed structure can be used to attenuate and suppress higher‐order modes. [ABSTRACT FROM AUTHOR]

In this paper the quad bend triangular resonator (QBTR) structure is used as a metamaterial unitcell for metasurface characteristics analysis. This paper presents the metasurface properties like electromagnetic band gap (dispersion diagram), reflection phase S 11 (deg) and surface impedance Z 11 (Ω) of a unitcell. The unitcell analysis shows similarities in operating frequency band for these metasurface characteristics. The QBTR metasurface performance is validated using a wideband dipole antenna. The antenna gain of > 5 dBi is achieved with QBTR metasurface for frequency range 3.2–6.7 GHz. The QBTR metasurface is orthogonal symmetric and can be used for dual-polarized wideband frequency applications like WLAN (5.15–5.85 GHz) and NR 5G sub-6-GHz (3.3–5.0 GHz). [ABSTRACT FROM AUTHOR]

In this paper, the authors present a proposal for an application of electromagnetic bandgap (EBG), for suppression of grating lobes, in frequency selective surfaces (FSS), not yet studied in the literature. An alternative type of EBG with square holes was proposed to reduce the computational effort in simulations. The study consists of an application of a rectangular periodic array of cylindrical and square holes in FSS dielectric substrate to create rejection bands and suppress specific resonant frequency modes. We built four prototypes and compared measured results with simulated results obtained with ANSYS HFSS. Simulations and measurements show suppression levels up to 6 dB. A good agreement between the results is observed. The FSS with EBG with square holes allows a simulation time 70 % lower than FSS with EBG with cylindrical holes. [ABSTRACT FROM AUTHOR]

Heart shaped reconfigurable band notched UWB microstrip line fed monopole antenna using two mushrooms like electromagnetic band gaps (EBGs) loaded by two varactor diodes has been developed, examined and fabricated. The effect of EBG dimensions, on the notch frequency, was first examined. A notched frequency of 5.3 GHz is obtained when two square EBGs with rectangular slits are used with length equal 7.5 mm and gap, g = 0.5 mm. The EBGs is loaded by a varactor diode to achieve re-configurability. The notch frequency covers WiMAX when varactor capacitance C = 0.7 pF and covers WLAN when C = 0.1pF. Also, the notch can be easily eliminated by decreasing the capacitance below 0.1 pF. A prototype of the proposed antenna using single capacitor elements with capacitances 0.6 pF is fabricated and S11 is measured. Notch frequency at 4 GHz is obtained in both simulated and measured antenna structures. The antenna with EBG has a directive radiation pattern in E-plane and omnidirectional pattern in H-plane. Also, the gain is suppressed in the notched frequencies. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. FEM and FIT are hired to simulate the proposed antenna structure using HFSS and CST respectively. Very good agreement between both results has been obtained. [ABSTRACT FROM AUTHOR]

This paper discusses the design of a low-profile Hilbert-shaped metamaterial (MTM) array-based printed circuit antenna forming a rectangular patch and backed by a partial ground plane; the rest of which is loaded with a square Electromagnetic Band Gap (EBG) structure for RF energy harvesting. The antenna is mounted on a 28 mm × 32 mm nickel oxide polymerized palm fiber (INP) substrate and compared to the identical one based FR4 substrate. The two prototypes are printed with silver nanoparticles (SNP). The antenna performance is tested numerically and experimentally in terms of S11 and radiation patterns. The obtained antenna gain bandwidth product of the INP prototype is found significantly better than the FR4 prototype. The proposed INP antenna gain at 5.8 GHz and 8 GHz frequencies are found about 4.56dBi and 7.38dBi, respectively. While, the FR4 antenna gain is found 4.56dBi and 6.85dBi at 5.8 GHz and 8 GHz, respectively. Finally, the collected output DC voltage and the conversion efficiency from the harvested RF energy are measured experimentally at 5.8 GHz and 8 GHz for both proposed prototypes. [ABSTRACT FROM AUTHOR]

In this paper, a moderate gain monopole antenna is proposed for GSM and Wi-Max applications. The antenna structure is constructed from a traditional printed monopole on Roger substrate of 3006 family. To enhance the antenna performance ultimately, an Electromagnetic Band Gap (EBG) layer is introduced to the antenna structure. A numerical analysis is applied based on a Finite Integral Technique (FIT) of CST Microwave Studio (CSTMWS) formulations to characterize the EBG unit cell in terms of S-parameters, dispersion and reflection diagram, as well as the constitutive electromagnetic properties. The antenna performance is tested numerically with and without the EBG structure in terms of S-parameters and radiation patterns. It is found that the proposed antenna provides an excellent matching, S11< −10 dB, at 1.85 and 3.3 GHz with 2.88 dBi and 5.8 dBi gain, respectively. Nevertheless, the Finite Element Method (FEM) based on Ansoft High Frequency Structure Simulator (HFSS) software package is invoked to compute the antenna performance. The antenna structure is fabricated and tested experimentally. Finally, an excellent agreement is found between the obtained numerical results from both software packages and measurements. [ABSTRACT FROM AUTHOR]

Excellent improvement on band notched characteristics of a circular ultra-wideband (UWB) printed antenna by embedding Frequency Selective Surface (FSS) at proper position in the far field is presented in this article. A square shaped mushroom Electromagnetic Band Gap (EBG) structure is placed beside the feeding line to achieve an elimination band of 3.7–4.2 GHz over the ultra-wideband range of 2.9–14 GHz showing fractional bandwidth of 131 %. The proposed antenna's electrical dimension is 0.29 λ × 0.367 λ × 0.015 λ. After embedding the properly designed FSS at optimal position along with the antenna the maximum gain of the radiating frequency increases from 7.1 dBi to 8.1 dBi and notch frequency gain reduces to −7.9 dBi from −5 dBi. Radiation efficiency at notch frequency also reduces from 31 % to 17 %. More than 10 dB Front to Back lobe Ratio (FBR) is obtained at 4.5 GHz. With the aid of Advanced Design Software (ADS), an equivalent circuit for the suggested antenna is created and its response is contrasted with measured and simulated outcomes. The proposed antenna is useful in UWB range with band rejection for C band satellite downlink. [ABSTRACT FROM AUTHOR]

A unique fractal printed patch antenna with defected EBG structured ground is presented for UWB reconfigurable applications. The antenna structure is modeled with influencing properties of fractal structure in association with dominating modes of ground deformities. This association is being observed for electromagnetic band gap patterns. This enables antenna to resonate in to the more eigen mode of excitations. In primary concern, designed structure has a very small dimension 18x21x1.6 mm³ and it is printed on commercially available FR4 substrate with dielectric constant 4.4 and thickness 1.6 mm. The designed structure is found resonating in wide range of frequency from 2.0 to 9.67 GHz. for suitable application of wireless Bluetooth communication (2.4 GHz), Wi-MAX (3.5/5.5 GHz), WLAN (5.2/5.8 GHz) and ISM(5.725/5.82 GHz). The antenna geometry is modeled and simulated on High Frequency Structure Simulator; the simulation results provide sustainable outcomes for the design validation of proposed structure. This paper gives prodigious explanation to the basic modeling and fabrication of the proposed structure. The return loss, VSWR parameters and radiation patterns are measured to make antenna feasible for reconfiguration over UWB applications. This helps antenna for an additional prominent feature of RF energy harvesting. [ABSTRACT FROM AUTHOR]

This communication presents a pattern reconfigurable antenna which is based on the Yagi-Uda configuration that can change the radiation beam into four directions. The function of the parasitic elements can be altered between a director and a reflector with PIN diodes while the driven element can be altered between two perpendicular directions with RF switches. To be able to use this proposed antenna on an electric conductor, such as on the vehicle rooftop, the antenna is thus mounted on electromagnetic band gap (EBG) structure which serves as a magnetic conductor. The gain is approximately 5 dBi and the field trial exhibited the diversity gain of 17 dB over the fixed beam antenna. As a result, the proposed antenna possesses high potential for further development into a TV signal reception on moving vehicles. [ABSTRACT FROM PUBLISHER]

Abstract: A fast analysis method, cell modified compact finite-difference time-domain method (CMC-FDTD), is presented to analyze the performance of electromagnetic band gap waveguides. The method calculates band diagrams in orthogonal coordinate system by translating nonorthogonal lattice to orthogonal lattice. It has highly stability for calculating dielectric and metallic material, either TE or TM mode, and reduces the requirement for memory. The comparisons are made among two numerical results and experimental one to validate the method. [Copyright &y& Elsevier]

In this paper, we present wideband common-mode (CM) noise suppression using a vertical stepped impedance electromagnetic bandgap (VSI-EBG) structure for high-speed differential signals in multilayer printed circuit boards. This technique is an original design that enables us to apply the VSI-EBG structure to differential signals without sacrificing the differential characteristics. In addition, the analytical dispersion equations for the bandgap prediction of the CM propagation in the VSIEBG structure are extracted, and the closed-form expressions for the bandgap cutoff frequencies are derived. Based on the dispersion equations, the effects of the impedance ratio, the EBG patch length, and via inductances on the bandgap of the VSI-EBG structure for differential signals are thoroughly examined. The proposed dispersion equations are verified through agreement with the full-wave simulation results. It is experimentally demonstrated that the proposed VSI-EBG structure for differential signaling suppresses the CM noise in the wideband frequency range without degrading the differential characteristics. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a generalized and easy to use method based on Hill''s equation and chain matrix concept is used to analyze the electromagnetic wave propagation in stratified dielectric and inhomogeneous media with arbitrary profiles. Numerical simulations are performed to compute the reflection and transmission of several Electromagnetic Bandgap (EBG) structures for various permittivity profiles and given polarization as well as incidence angles of driving fields. Multilayer structures are analyzed and optimized to enhance their selectivity performances. Obtained results agree excellently well with other published data. [Copyright &y& Elsevier]