A highly efficient Rectangular Microstrip Antenna with hexagonal holes as an Electromagnetic Bandgap structure in the ground plane

This paper presents a printed rectangular slot microstrip antenna array of two elements based on an Electromagnetic Band Gap (EBG) structure. The proposed EBG structure is invented to improve the isolation between the radiating elements for multiple-input multiple-output (MIMO) application. Single and two slotted rectangular microstrip antennas are designed on an FR-4 substrate with a dielectric constant (εr) of 4.3 and loss tangent (tanδ) of 0.025 with thickness of 1.6 mm. The proposed EBG structure is designed as one planar row of 24 slots. The proposed array performance is tested numerically using Computer Simulation Technology Microwave Studio (CSTMW) of Finite Integration Technique (FIT) formulations. The antenna performance in terms of reflection coefficient (S11), isolation coefficient (S21), radiation patterns, boresight gain and Envelope Correlation Coefficient (ECC) are investigated before and after introducing the EBG structure to identify the significant enhancements. The proposed EBG structure is located between the radiating antenna elements to reduce the mutual coupling of the proposed antenna array. The edge to edge separation distance of the proposed antennas is λ0/16, where the λ0 is the free space wavelength at 2.45 GHz. The simulated results show a significant isolation enhancement from –6 dB to –29 dB at the first resonant frequency 2.45 GHz and from –10 dB to –25 dB at the second resonant frequency 5.8 GHz after introducing the EBG structure to the antenna array.

In this paper a novel microstrip antenna is proposed using electromagnetic band gap (EBG) structure for mobile and wireless applications. It covers two mobile bands ranging from (2.20–2.29) GHz and (2.29–2.30) GHz. An extremely compact size EBG structure is applied in a square shape. After applying EBG structure to the proposed design, performance characteristics such as percentage bandwidth and return loss enhance by 5.1% and 5% respectively. Also by changing the feed and shorting pole (via) position, the same structure is used for ISM (2.45 ± 0.05) GHz band with resonant frequency 2.45 GHz. The measured and simulated results show very good agreement. The design structure is fabricated using FR4 substrate with dielectric constant 4.4, loss tangent 0.02 and thickness 1.6 mm.

Band notched circular monopole antennas for ultra-wide band applications are proposed in this paper. The proposed antennas in this paper can reject worldwide interoperability for microwave access WiMAX band (3.3–3.8 GHz) and wireless local area network WLAN band (5–6 GHz). Antennas utilises mushroom-type electromagnetic band gap (EBG) structures and I-slot embedded edge located via (ELV) EBG structures to achieve band-notched designs. The advantages of band notched designs using EBG structures like notch-frequency tuning, dual-notch antenna designs and stable radiation pattern are also verified. Various antenna designs with slot in EBG structures, variations in placement of EBG structures, number of EBG structures and ELV type EBG structures are simulated. About 30% reduction in size of EBG structures is obtained if conventional mushroom type EBG is replaced by proposed I-slot embedded ELV-EBG structure. Fabricated and measured results are in good agreement with simulated ones.

Electromagnetic Bandgap (EBG) structures have been successfully applied for suppressing the Simultaneous Switching Noise (SSN) between the power and ground planes. Aimed at the relative narrow bandwidth and the poor performance in low frequency of the conventional Uniplanar-Compact EBG (UC-EBG) structure, a novel EBG structure formed by adding spiral-shaped metal strips on the conventional UC-EBG is proposed. This new EBG structure significantly enhance the equivalent inductance between the neighboring nuit cells, as well as change the character of the stop-band. Simulation results show that the new EBG structure can achieve a bandwidth reach 4.35GHz.This stop-band is 47.5% wider than the conventional UC-EBG structure, and 17.5% wider than the reference EBG structure in literature. The excellent SSN suppression is achieved between 0.18-4.53GHz in the depth of -40dB.

This paper discusses the comparative effect of Electromagnetic Band Gap (EBG) structures on two element Microstrip antenna array. The dielectric substrate used is FR-4 glass epoxy with dielectric constant 4.2 and loss tangent 0.0245. The conventional antenna array is resonating at a frequency of 5.53 GHz with a mutual coupling of -17.83 dB. The first proposed antenna array with square slot EBG structure in the ground plane and fractal patch EBG structure on the surface produces a mutual coupling of -50.21 dB and a gain of 8.78 dB at 5.53 GHz. The second proposed antenna array with star slot EBG structure in the ground plane and diamond patch EBG structure on the surface produces a mutual coupling of -51.63 dB and a gain of 7.20 dB at 5.53 GHz. Both the proposed antenna arrays are producing appreciable decrease in back lobe radiation. The antenna arrays are designed using Mentor Graphics IE3D software and measured are obtained using vector network analyzer.

This paper proposes a reconfigured horn antenna with reduced side-lobe radiation by using electromagnetic band gap (EBG) structure. A mushroom-like structure with a circular-shaped patch as unit cell is designed to achieve a complete EBG. The EBG structure is lined on the metal wall along the E-plane of the horn antenna. This causes the surface waves on the metal wall to be suppressed, resulting in lower side-lobe emission. A conducting wedge is inserted on the gap between the EBG structure and waveguide feed aperture to achieve impedance matching in the antenna. In addition, the proposed horn antenna is suitable for high power systems due to a purely metallic construction of the EBG structure.

In this paper, we present an equivalent circuit (EC) based technique which combined with the numerical method to optimize the EBG structures with simple square-loop frequency selective surfaces (FSSs), they can take on in-phase reflection characteristic in some broad-band electromagnetic band gap (EBG) structures. By using the multilayered FSSs in this type of EBG structure, the surface waves and current could stopped effectively. The geometry and working of the antenna with this EBG structure are detailed and the design method is proposed.

This paper presents a design of a dielectric resonator antenna (DRA) for millimeter-wave applications. An electromagnetic band gap (EBG) structure is used in the antenna design to enhance the antenna characteristics. The simulated with and without EBG results of the designed antenna is calculated to show the parameters such as impedance bandwidth, reflection coefficient, and gain. The parameters of the proposed antenna have improved after the periodic unit cell structure (EBG) introduction. The obtained reflection coefficients of the proposed antenna with and without EBG structure are −30.5 dB and −20.8 dB, respectively. In the presence of an EBG structure antenna shows a peak gain of 25 dBi, which is higher than the without EBG (8 dBi) structure. The designed antenna resonates at 33 GHz with an impedance bandwidth of 700 MHz. The Ansys HFSS software is used to design and simulate the proposed antenna.

The reflection variation property of Electromagnetic Band-Gap (EBG) structures can be utilized to reduce the Radar Cross Section (RCS) of ground planes. Combining PEC and EBG structures on the same ground plane forms checkerboard surfaces which can achieve a RCS reduction in a narrow frequency band. However, a wider band RCS reduction can be realized by combining two different EBG structures. It can realize 60% frequency bandwidth for the 10-dB RCS reduction. The scattered fields for square checkerboard surfaces are re-directed toward four quadrants, while the scattering for hexagonal checkerboard surfaces are toward six directions. The maxima of the RCS for checkerboard surfaces in the four quadrants are 10 dB less than those of the PEC ground plane, and more than 19 dB RCS reduction is obtained along the principal planes. Both bistatic and monostatic RCS are compared with those of the equal-sized PEC ground planes.

The paper aims to determine the Green's functions for different realizations of electromagnetic band-gap (EBG) structures and to calculate the coupling between two dipoles placed above these EBG structures. The applied method avoids the complexity of the Floquet mode approach and the limitations of the surface wave approach. For each considered structure, some sort of asymptotic boundary conditions are derived in which the periodicity of the structure is assumed to be negligible compared to the wavelength. The goal (and the test) of the applied method is to determine properties of each considered EBG structure. Therefore, all important physical phenomena should be taken into account. In order to be able to analyze multilayer structures, the analysis model has been implemented in the G1DMULT algorithm that calculates the spectral domain Green's functions of planar, circular-cylindrical and spherical multilayer structures (Sipus, Z. et al., App. Computational Electromagnetics Soc. J., vol.13, p.243-54, 1998).

For 60-GHz band communications, both the mutual coupling and transmission distance restrict the performance of a multiple-input multiple-output (MIMO) antenna array. Several studies presented different types of meta-materials and electromagnetic bandgap (EBG) structures to improve the performance of a MIMO antenna array at the 60-GHz band. In this paper, we presented the four-element MIMO patch antenna with different types of EBG structures for the millimeter wave (mmW)communications at the 60-GHz unlicensed industrial, scientific, and medical band. The single element of the MIMO antenna array covered the mmW band from 57 GHz to 63 GHz having the dimensions of 1.3 mm × 1.8 mm × 0.1 mm. We developed a set of square-shaped, cross-shaped, and complex-slotted EBG ground planes between the antenna elements for the performance improvement. All the three EBG ground planes provided significant coupling reduction between the mmW MIMO antenna elements. The proposed EBG structures exhibited wide bandgap characteristics and improved scattering parameters in the desired frequency band. In contrast with the cross- and complex-slotted, the square-shaped EBG structure substantially improved the overall gain of MIMO antenna array. In addition, the square-shaped EBG reformed the maximum beam and enhanced the far-field gain pattern in the desired direction. Experimental results conducted with the fabricated prototypes showed a good agreement with the simulation results and adequately covered the 60-GHz band. The low-profile and salient features of the proposed MIMO antenna array shows the potential for on-chip applications at 60 GHz.

This article divulges regarding the design and characterization of an antenna together with electromagnetic periodic bandgap structures for C-band applications. These periodic structures include the materials to setup different innovative structures that are usually found in many applications for industry and military purposes. Normally, substrates with metallic patches are associated along these structures that acquire dimensions usually less than that of its operating wavelength (λ). When compared to normal design of microstrip antenna, we found enhancement in efficiency and bandwidth for the structure approximated upon placing it on modified ground surface. For a certain encountered external conditions, basically, there is less deliberation on optimized design and also on its performance, but maximum literatures concentrate especially on computational aspects of electromagnetic band gap (EBG) structures. The basic design encountered in the paper is associated with a set of octagonal slots within the substrate confined with both ground plane and patch. The dimensions of parameters for designing the antenna model are obtained by the concept of optimization using high-frequency structure simulator (HFSS) tool that can resonate at desired frequency. A better return loss of −21.09 dB is recorded with this structure when compared with normal conventional patch antenna. The proposed design is resonating at 6.9 GHz.KeywordsEBG structureOctagonal slotsOptimizationPatch antennaC-band frequency range

This paper presents a circularly polarized printed circuit board (PCB) patch antenna using mushroom-like electromagnetic band gap (EBG) structure for gain enhancement. Unlike the popular method of using artificial magnetic conductor (AMC) or EBG structure as the ground of the antenna, we place the mushroom-like EBG structure around the patch antenna to avoid increasing the number of PCB layers. The EBG structure works in-phase reflection around 24.25 GHz by optimizing design. Limited by the size of the antenna, only twelve EBG units can be distributed around the corner-cut square circularly polarized patch antenna. Simulation results show that gain of the antenna enhances 0.8 dB and cross polarized gain reduces about 15 dB, moreover, the axial ratio is also improved.

Electromagnetic Bandgap (EBG) structures are increasingly utilized by a variety of microwave and optical devices as filters for unwanted signals. One such application is their incorporation in power distribution network (PDN) of electronic circuits where the EBG structure replaces one of the reference voltage planes thus forming a shielded EBG structure. The EBG induces a wide (on the order of few GHz) omni-directional stopband in the operating frequency range of the PDN which mitigates the so called simultaneous switching noise (SSN) on the power plane. The challenging aspect in designing an EBG for such applications is to achieve a wide stopband centered at low GHz frequencies while maintaining a reasonably small unit cell size and a low profile. Indeed, the dimensions of the unit cell of the EBG structure for low frequency designs can become relatively large with respect to the size of the host dielectric substrate. Therefore, availability of a systematic design approach that can provide a fast and accurate means of performance prediction to enable geometry tweaking and design optimization will be of critical importance in utilizing EBG structures in such applications.

The objective of this work is to design a printed antenna that has at once a low profile, a wide bandwidth and a high gain. In order to achieve this objective, this paper has based its study on the theory of Electromagnetic Band Gap (EBG) structures where the EBG structure is exploited as the ground plane of the antenna. In a first part, the geometry and the electromagnetic performances of the printed antenna originally designed on classic ground plane will be described. In the second part, the results obtained for this antenna designed on ground plan based on a new EBG structure proposed are illustrated. In the last section, a comparison between the results obtained can be found, in which the improvements brought by the new EBG structure are illustrated.