Electromagnetic Bandgap Structure Research Articles

Mutual coupling suppression of MIMO array with non-uniform curved-strip EBG structure via shape and layout co-optimization

In this paper, a shape and layout co-optimization method for mutual coupling suppression of MIMO array with non-uniform curved-strip electromagnetic bandgap (EBG) structure is proposed. The curved shape of the EBG structure between the microstrip patches is described to achieve the mutual coupling suppression by the spline curve and moving it the same displacement along the y-axis in both directions, where the spline curve is formed by the coordinates of the control points corresponding to the Bessel function. Moreover, the non-uniform layout design of the EBG structure is introduced to further adjust the radiation field and the surface current distribution of the coupled array. Through simultaneously optimizing the curved shape and layout parameters of the strip EBG structure, the expected array radiation and decoupling performances are obtained. The effectiveness of the proposed method is validated by a MIMO array with edge-to-edge distance of only 0.1λ0 in the 5G WLAN frequency band. The simulation and experiment results indicate that, compared with non-EBG and the initial uniform strip EBG, the proposed EBG structure can provide the advantage of significantly reducing the mutual coupling to −35.20 dB and effectively improving the isolation between the elements, meanwhile ensuring the MIMO array performances.

Isolation enhancement of a two- orthogonal printed elliptical slot MIMO antenna array with EBG structure for millimeter wave 5G applications

This work investigates a high-isolation Orthogonal Printed Elliptical Slot Antenna (OPESA) array with Multiple Inputs and Multiple Outputs (MIMO). A unique composite Electromagnetic Band-Gap (EBG) structure consisting of a vertical six rings positioned between single element antennas were devised and investigated with the aim of reducing mutual interaction between antenna components. A distinct feeble electric field that could successfully inhibit the Mutual Coupling (MC) among the antenna components is easily produced by the suggested composite EBG construction. One type of decoupling constructions throughout the antenna growth was carefully examined at together the theoretical and physical levels in order to offer a clear representation of the suggested antenna array’s design concept and decoupling technique. The antenna array design process was cleverly separated into three stages. In order to verify the suggested decoupling idea, the array Scheme was constructed, assessed, and measured. Studying the antenna gain, radiation pattern, and reflection coefficient, it was found that the simulated and measured findings were very consistent. According to the models, the array has an extreme radiation efficiency of about 91%, a minor value of Envelope Correlation Coefficient (ECC < 1.8 × 10−4), and a maximal gain of 11.5 dBi. The electrical size, highest isolating grade and the recommended MIMO antenna’s 90 dB isolating bandwidth (BW) were assessed. The planned antenna has several appealing features that set it apart from previous similar designs. These features include a low design complexity, a great Diversity Gain rate (DG > 9.99 dB), the BW of the proposed antenna extends from 25 GHz to more than 40 GHz, an enormously great isolation level (about 90 dB), and compressed dimensions (51 mm × 30 × 1.6 mm). For verifying the recommended antenna for MIMO. the suggested MIMO antenna design’s radiation efficiency, a thorough time-domain study is suggested.

Enhancing MIMO Antenna Isolation with Novel Electromagnetic Band Gap (EBG) Structure and Genetic Algorithm Optimization

ABSTRACT A novel Electromagnetic Band Gap (EBG) structure is proposed to minimize common connector between closely spaced rectangular patch antennas. The 2D EBG architecture is placed on the horizontal plane of a 1/2 rectangle patch antenna array, reducing mutual coupling by over 20 dB without compromising far-field performance, gain, or bandwidth. By optimizing the EBG structure using a genetic algorithm, noise is reduced by −60 dB compared to −25 dB without it, improving the isolation of the antenna array. Inserting 3 EBG modules between the two patches decreases the 2.45 GHz mutual coupling to −60 dB, showcasing the significant enhancement in isolation. This MIMO antenna design with an EBG structure is suitable for wireless LAN communication systems, offering improved signal separation and performance. The proposed method integrates square patch antennas operating at 24 GHz with a metamaterial EBG structure on a Rogers R04350B substrate, using a genetic algorithm for optimization. Experimental results demonstrate over 22 dB improvement in isolation between antenna elements, maintaining consistent radiation patterns across frequencies.

High Gain Compact Antenna-in-Package Solution Using Like Mushroom Electromagnetic Band Gap for Industrial, Scientific, and Medical Band

Abstract A single-feed circularly polarized antenna with electromagnetic band gap (EBG) has been developed for the Industrial, Scientific, and Medical (ISM) bands. The proposed antenna features a square patch with eight slits on each side and corner, along with a cross-slot in the middle. To prevent surface wave excitation caused by the patch antenna's thick substrate, new grounded like-mushroom EBG structures will surround the antenna. The frequency band gap characteristics of the EBG unit cells have been optimized at 5.8 GHz. A row of EBGs squares is 4.73 mm (0.063λo) away from the antenna square patch and surrounds it on all four sides. The proposed mushroom-like structure design improves the antenna's directivity by 43.31%, gain by 32.93%, reflection coefficient by 93%, and radiation efficiency by 35.22%. This topology enables a wide variety of wireless communications applications. Computer simulation technologies (CSTs) were used to generate simulation figures for the proposed antenna, operating at 5.8 GHz. Furthermore, the new Like-Mushroom EBG antenna simulation, experimental results, and other reported works confirm that our approach meets the studied objectives regarding polarization purity, radiation efficiency, high directivity, and gain.

Notch band characteristics improvement of a printed ultra wideband antenna by embedding frequency Selective Surface

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 0.29λ×0.367λ×0.015λ. 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.

A Multifunctionality Reconfigurable HMSIW Filter by Using EBG Structure and Diodes for C/X-Band Application

This letter presents a multifunctionality reconfigurable substrate-integrated waveguide (SIW) filter embedded in a microstrip line. The proposed filter used an electromagnetic bandgap structure (EBG) to compact the size and improve the electromagnetic features. The SIW filter consists of a three-cell EBG with metallic circular-shaped connected to the ground through cylindrical vias. Firstly, the base SIW structure offers a wide passband filtering response, and then, to obtain selective passband, wide band rejection, and controllable resonance frequencies, a three-cell EBG along with four diodes has been attached. The filter is designed and printed on a Rogers 4003 substrate with a thickness of 1 mm and is experimentally validated for functionalities operated at three modes with an average 3 dB bandwidth of 115 MHz in each frequency. In addition to that, two transmission zeros (TZ) have been produced in the upper band frequency. The filter’s response is also tunable by turning the diode off or on and changing the main parameters of EBG, the gab, and the position between cells. The study explores resonance frequency alterations in a three-state system of on/off. By eliminating or diminishing specific modes, and incorporating diodes, distinct resonance behaviors are observed. Moreover, shifting frequency resonance in a multiparameter system has been investigated. Increasing B1 induces a significant shift to lower values, while an increase in D1 leads to a decrease in the first and second resonance frequencies and an upward shift in the third. The designed filter has been fabricated and tested to compare and confirm simulated responses. Simulation and measurement results are in good agreement. The S-parameters of measured results gained a good response (&gt;15 dB) within the passbands and stopbands and an insertion loss of 1.5 dB suitable for 5G and Wi-Fi systems.

Design of a Reconfigurable Band-notched Wideband Antenna using EBG Structures

A compact WLAN band-notched reconfigurable wideband antenna using two mushroom-like electromagnetic band-gap (EBG) structures is proposed in this paper. It is designed based on a dual wideband microstrip feed patch antenna with operating frequency bands of 2.2-3.7 GHz and 4.8-6 GHz. One of the EBG cells is positioned alongside the feed line, while the other EBG cell is laid on the back of the substrate. The patch or ground of the two EBG units are fed with a stronger current through a ground slot and a parasitic stub respectively, and the connections between the EBG structures and the antenna are controlled by loading a PIN diode with two 56 pF DC blocking capacitors. The advantage of this proposed design is that the antenna and the EBG unit can be designed independently. The proposed antenna has an overall size of 35×46×1.6 mm3. When testing the S11 of the antenna, the influence of the bias circuit on the antenna is also considered. The measured results show that the proposed antenna can generate two notched bands of 2.3-2.49 GHz and 5.11-5.51 GHz of WLAN, and the realized gain in the notch bands can be reduced to -2.65 dBi and -4.55 dBi, respectively, demonstrating its anti-interference characteristics, and can be applied in band notch broadband communication systems or anti-interference communication equipments such as unmanned aerial vehicles and radars.

The design and decoupling of TX/RX antenna with omnidirectional conical beam operating at V band

Abstract In this work, a high isolation transmitter–receiver antenna with omnidirectional conical beam operating at 61.5 GHz is presented. The proposed dual-antenna system consists of a transmitter (TX) antenna and a receiver (RX) antenna with the same structure, composed of a circular metal patch with ring slot and metal shorting vias, fed by a coaxial probe at their respective geometric center. And both antennas are placed on a circular metal platform, positioned symmetrically with each other. To increase the isolation between them, three different decoupling methods are proposed, and the one with an electromagnetic band gap (EBG) structure added in-between shows the most promising decoupling effect, as the surface wave current can be maximally suppressed. The overall size of the antenna system is 2.2552 × π × 0.579 λ 0 3, where λ 0 is the free space wavelength at 61.5 GHz. A prototype of the proposed antenna system with EBG decoupling structure is fabricated and measured, demonstrating that the TX–RX isolation is 57.9 dB at 61.5 GHz, 21.6 dB better than that without decoupling structure, with omnidirectional conical beam radiation achieved at the same time.

A Design Method and Application of Meta-Surface-Based Arbitrary Passband Filter for Terahertz Communication.

A meta-surface-based arbitrary bandwidth filter realization method for terahertz (THz) future communications is presented. The approach involves integrating a meta-surface-based bandstop filter into an ultra-wideband (UWB) bandpass filter and adjusting the operating frequency range of the meta-surface bandstop filter to realize the design of arbitrary bandwidth filters. It effectively addresses the complexity of designing traditional arbitrary bandwidth filters and the challenges in achieving impedance matching. To underscore its practicality, the paper employs silicon substrate integrated gap waveguide (SSIGW) and this method to craft a THz filter. To begin, design equations for electromagnetic band gap (EBG) structures were developed in accordance with the requirements of through-silicon via (TSV) and applied to the design of the SSIGW. Subsequently, this article employs equivalent transmission line models and equivalent circuits to conduct theoretical analyses for both the UWB passband and the meta-surface stopband portions. The proposed THz filter boasts a center frequency of 0.151 THz, a relative bandwidth of 6.9%, insertion loss below 0.68 dB, and stopbands exceeding 20 GHz in both upper and lower ranges. The in-band group delay is 0.119 ± 0.048 ns. Compared to reported THz filters, the SSIGW filter boasts advantages such as low loss and minimal delay, making it even more suitable for future wireless communication.

Screen‐printed dual‐band wearable textile antenna incorporated with EBG structure for WBAN communications

SummaryA dual‐band, wearable coplanar microstrip patch antenna (CPW) integrated with electromagnetic bandgap structure (EBG) to operate dual wireless bands at 2.48 GHz industrial, scientific, and medical band (ISM) and 5.2 GHz WLAN. The proposed textile wearable antenna and EBG structure are screen‐printed using silver conductive ink on the cotton polyester substrate (εr = 1.6) for flexible wearable applications. A 3 × 3 EBG array is realized by a concentric square patch surrounded by the annular square ring to reduce back radiation and increase the forward gain and front‐back ratio. The proposed EBG‐backed antenna, compared with the conventional CPW‐fed antenna, improves forward gain from 2.18 to 6.59 dB at 2.48 GHz and 3.5 to 7.03 dB at 5.2 GHz. Moreover, the EBG array is used to isolate the human body from the antenna and reduces the specific absorption rate (SAR). The antenna is performed with a human phantom tissue model, which exhibits a specific absorption rate of 0.12 W/kg, and 0.260 W/kg for 1 g tissue at 2.48 GHz and 5.2 GHz, respectively.

A Frequency Reconfigurable Graphene-Based Microstrip Antenna with Mushroom-Like EBG

The growing demand for wireless applications has led to network congestion issues. In response, network operators have recommended a transition to higher frequencies, particularly within the unlicensed millimeter-wave (mm-wave) spectrum. This shift aims to fulfill users' desires for rapid data transmission within personal networks, whether at home or in the office, exemplified by technologies like WiGig technology and indoor applications. However, a significant challenge in achieving high data transfer speeds within this frequency range lies in the design of the antenna. These antennas must strike a balance between size and performance. Microstrip Patch (MP) antennas have gained recognition for their compact form and seamless integration into mobile communication systems. Nonetheless, they grapple with limitations such as poor gain and narrow bandwidth, largely attributable to surface waves negatively impacting antenna performance. In this study, we introduce, design, and optimize an MP antenna tailored for 60 GHz applications. To enhance the performance of the MP antenna, we introduce various mushroom-like Electromagnetic Bandgap (EBG) structures. These structures address the propagation of the surface waves issue that affects the antenna performance. Additionally, to create a tunable frequency antenna the variable conductivity of the graphene material is used in the form of implanted slots on the patch and tuned by applied DC voltage on the slots. Finally, the parameters of the MP antenna undergo enhancement based on simulation results obtained through CST software.

An electromagnetic bandgap structure assisted MIMO antenna with an optimisation driven hybrid beam forming model

An electromagnetic bandgap structure assisted MIMO antenna with an optimisation driven hybrid beam forming model

Multi-objective hybrid optimization for micro strip patch antenna design

Due to their low price, light weights, as well as simple installation, Micro strip Patch Antennas (MPAs) have been made to perform in a double and multi-band applications. The MP receiver is created with an Electromagnetic Band Gap (EBG) structure in order to decrease the micro strip patch cross-polarized radiation but also achieve the crucial radiation criteria. The polymeric liquid crystals substratum is employed to decrease raw material costs, and also the applicable shape framework are employed to enhance receiver execution. We have established a new optimization based method which has two operating stages. In the begining stage, we have designed a Micro strip patch antenna with certain parameters. Afterwards, these design parameters length, width, height, substrate thickness under area such as get optimized by the newly introduced Battle Royale Customized Spider Monkey Optimization (BRCSMO) algorithm in order to get an antenna with higher performance. We have evaluated the proposed method with regard to measures like receiver profit, productivity, bandwidth, decline loss as well as Total Active Reflection coefficient (TARC) and the outcomes showed that this proposed technique can offer superior outcomes than other approaches.

A multi-beam circularly polarised Fabry-Perot resonator antenna array using SIW for X-Band applications

ABSTRACT This paper presents a novel multi-layer beamforming antenna array based on Fabry-Perot resonator that is excited by a high-performance compact 4 × 4 Butler matrix using substrate integrated waveguide (SIW) technology for X-band application. The adapted ring patch antenna is fed through the aperture on a rectangular SIW cavity and forms the radiating element in the antenna array. Enhanced characteristics of the antenna array are realised by inserting an electromagnetic bandgap (EBG) structure between the radiating elements and a superstrate constituted from two complementary frequency selective surfaces (FSS) that forms a Fabry-Perot resonator (FPR). Circular polarisation in the proposed FPR SIW antenna array (FPRSAA) is achieved by using a combination of sequential phase rotation and orthogonal feeding techniques. Measured results of antenna array (Ant. II) show |S11| ≤ −10 dB between 8–12.0 GHz, a circular polarisation (CP) gain variation between 15.64–18.54 dBic, 3 dB axial-ratio between 8.5–11 GHz, and scanning angle covering −47 to 47 degrees.

Bandwidth-enhanced FSS-loaded Semi-circular Patch Antenna for C-band Applications

Aim: This study aimed to develop and analyse a bandwidth-enhanced C band antenna loaded with EBG and FSS Structures to improve the antenna performance. Methods: This paper illustrates the design of a semi-circular microstrip antenna with a modified circular ring Frequency Selective Surface (FSS) and an Electromagnetic Band Gap (EBG) structure for improved bandwidth and an omnidirectional pattern. The patch antenna is aimed at C-Band intersatellite communication links in a constellation. Results and Discussion: In literature, the application of EBG and FSS together is seldom used. The semicircular patch is aimed at retaining the omnidirectional antenna pattern at higher frequencies, as well as bandwidth, which is achieved through FSS and EBG structures. The modeling and simulation of the antenna have been carried out with 3D EM solvers. The simulated patch antenna operates in a wideband ranging from 4.1 GHz to 7.1 GHz with a gain of 1.9 dB at 5.33 GHz and 1.4 dB at 4.5 GHz. Conclusion: The proposed antenna design is vertically polarized. The simulation results are validated with measurement results.

A wideband, thin profile and enhanced gain microstrip patch antenna modified by novel mushroom-like EBG and periodic defected ground structures

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.

Novel Meandered Line EBG Filters with Significant Size Reduction Using Sine Tapering

Tapering electromagnetic bandgap (EBG) structures is a common method in designing microstrip filters with different periodic structures. A novel technique for tapering EBG structures with the amplitude coefficients obtained from the sine function has been illustrated. This method deduces mellifluous coefficients that improves the performance with reasonable stopband width, preferable insertion loss level, and much-minimized passband ripples compared to similar designs with other tapering methods (e.g., binomial distribution, Chebyshev distribution, and conventional cosine tapering). It also offers tandem use of tapered EBG structures, leading to the novel meandered transmission line tandem design that significantly reduces the length of the filter; more than 40% is possible, compared to the uniform and conventional tapered designs. Size reduction on such a large scale will benefit the designers with the limited space issues.

Implementation of EBG Structure to Reduce Surface Wave Excitations for IoT Range Applications

This paper presents the design of antenna for Internet of Things (IoT) applications. The performance of conventional antenna is limited by surface waves due to which it produces a low gain. An attempt is made to reduce the surface wave excitations in conventional antennas with the use of integration of Electromagnetic Band Gap (EBG) cells. The proposed work involves the design of Edge via EBG unit cell at 5.2 GHz and it is simulated with High Frequency Structure Simulator (HFSS) software. The simulation results show that the gain is enhanced by 10% and S11 is reduced by 72%, approximately in the rectangular microstrip patch antenna with Edge via EBGs.

A multiband slot antenna with groundless EBG structure for wearable WLAN/WiMAX applications

ABSTRACT A multiband microstrip antenna integrated with an electromagnetic bandgap (EBG) structure operating at WLAN and WiMAX frequencies is proposed for wearable applications. The antenna consists of a circular patch surrounded by the ground plane, separated by a ring slot. The size of the integrated antenna has been significantly reduced to 0.28 ×0.28 and thickness of 0.024 . A single-layered planar groundless EBG structure has been designed to suppress the wideband of frequencies from 2.2 to 5.4 GHz. An equivalent circuit model is presented to explain the zero-degree reflection phase of the EBG. Integration of the antenna with the EBG structure and a simple resonator bestows operating bands at 2.45 and 5.2, 5.5 and 5.8 GHz with significantly low back radiation. The gain and directivity of the antenna have been increased to 5.41 dB and 6.2 dB, respectively. The Specific Absorption Rate (SAR) of the antenna has been reduced to 0.0859W/kg, which is significantly lower than the admissible SAR value recommended by the Federal Communications Commission (FCC). The antenna is fabricated on an FR4 substrate, and its measured radiation characteristics are well matched to the simulated one.

Design of a Low Profile Archimedean Spiral Antenna using Compact Defected Ground Structure as a Reflector

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.