Patch Electromagnetic Band Gap Research Articles

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.

Multi-band frequency reconfigurable antenna using EBG and parasitic patches

ABSTRACT This article demonstrated a compact reconfigurable microstrip antenna with a multi-band configuration. It resonates for three different frequency configurations, including the single and dual bands. The primary rectangular patch antenna resonates for WLAN (5.2 GHz center frequency) band. The reconfigurable electromagnetic bandgap (EBG) and parasitic patches near the feed line produce 4 and 6.33 GHz resonance. The defected ground structure is integrated with a PIN diode to make reconfigurable EBG, and it resonated at C band (4 GHz). The PIN diode switching configuration embedded with EBG and one square patch creates dual-band characteristics in wireless local-area network (WLAN) and International Telecommunication Union (ITU) bands. Other PIN diodes switching configurations with primary antenna and two other patches work for C and WLAN bands. The proposed antenna resonated at 4, 5.2, and 6.33 GHz frequencies with different switching configurations of the PIN diode. The simulated results of this novel antenna configuration verified with measured consequences for antenna parameters like reflection coefficient and radiation characteristics are also presented.

Design and Sensitivity Analysis of EBG Stripline Common-Mode Filters

Workflow of electromagnetic bandgap (EBG) common-mode (CM) filter design of edge-coupled differential pairs on a printed circuit board (PCB) and sensitivity of its characteristics to variations of geometrical and material parameters are discussed. A number of simple 20-GHz EBG CM notch filters for differential stripline pairs are designed using full-wave numerical electromagnetic modeling, fabricating, and testing. The cases of one and two stripline differential pairs crossing the EBG patches are considered. The modeled and measured mixed-mode S -parameters are analyzed as functions of geometrical parameters, including size and number of EBG patches, gaps between them, geometry and position of signal traces across the EBG patches, and thicknesses of dielectric layers. The agreement between the measured and modeled mixed-mode S- parameters validates the models and allows for further numerical experiments. It is shown that the EBG filter performance depends on various subtle technological features, e.g., conductor surface roughness on metal surfaces; length imbalance on a differential pair; rate of coupling of lines within each differential pair and between the pairs; and some other factors. The systematic analysis of the trends for filter characteristics as functions of various design parameters allows for an optimal design of the CM notch filter.

Wideband Suppression of Radiated Emissions from a Power Bus in High-Speed Printed Circuit Boards

We present experimental demonstrations of electromagnetic bandgap (EBG) structures for the wideband suppression of radiated emissions from a power bus in high-speed printed circuit boards (PCBs). In most of the PCB designs, a parallel plate waveguide (PPW) structure is employed for a power bus. This structure significantly produces the wideband-radiated emissions resulting from parallel plate modes. To suppress the parallel plate modes in the wideband frequency range, the power buses based on the electromagnetic bandgap structure with a defected ground structure (DGS) are presented. DGSs are applied to a metal plane that is connected to a rectangular EBG patch by using a via structure. The use of the DGS increases the characteristic impedance value of a unit cell, thereby substantially improving the suppression bandwidth of the radiated emissions. It is experimentally demonstrated that the DGS-EBG structure significantly mitigates the radiated emissions over the frequency range of 0.5 GHz to 2 GHz as compared to the PPW.

Reflection Phase Characteristics of EBG Structures and WLAN Band Notched Circular Monopole Antenna Design

Circular monopole antenna for Ultra wide band (UWB) applications with band notch property is proposed. The proposed antenna rejects wireless local area network WLAN band (5-6 GHz). In this paper reflection phase property of EBG structures is proved using mathematical analysis. Furthermore reflection phase and dispersion diagram both estimate same band gap in EBG structures.Antenna utilises modified mushroom-type Electromagnetic Band Gap (EBG) structures to achieve band-notched design. The advantages of band notched designs using EBG structures like notch-frequency tuning, antenna design independent approach and stable radiation pattern are also shown. About 7 % reduction in size of EBG patch is obtained if conventional mushroom type EBG is replaced by proposed I-slot type EBG. Fabricated and measured results are in good agreement with simulated ones.

A Novel 2D Z-Shaped Electromagnetic Bandgap Structure

This paper researches a novel 2D Z-shaped Electromagnetic Band-Gap (EBG) structure, its dispersion diagram and application field. Based on a transmission line model, the dispersion equation is derived and theoretically investigated. In order to validate theoretical results, a full wave analysis is performed and the electromagnetic properties of the structure are revealed. The theoretical results show good agreement with the full wave simulation results. The frequency response of the structure is compared to the well know structures of Jerusalem cross and patch EBG. The results show the applicability of the proposed 2D Z-shaped EBG in microstrip patch antennas, microstrip filters and high speed switching circuits, where the suppression of parasitic surface wave is required.

A Novel 2D Z-Shaped Electromagnetic Bandgap Structure

This paper researches a novel 2D Z-shaped Electromagnetic Band-Gap (EBG) structure, its dispersion diagram and application field. Based on a transmission line model, the dispersion equation is derived and theoretically investigated. In order to validate theoretical results, a full wave analysis is performed and the electromagnetic properties of the structure are revealed. The theoretical results show good agreement with the full wave simulation results. The frequency response of the structure is compared to the well know structures of Jerusalem cross and patch EBG. The results show the applicability of the proposed 2D Z-shaped EBG in microstrip patch antennas, microstrip filters and high speed switching circuits, where the suppression of parasitic surface wave is required.

Millimeter-Wave EBG-Based Aperture-Coupled Dielectric Resonator Antenna

Design, fabrication and testing of millimeter-wave (MMW) dielectric resonator antenna (DRA) surrounded by electromagnetic band-gap (EBG) structure are presented. For this purpose, MMW mushroom-like, circular patch EBG (CP-EBG) cell is designed and fabricated. The propagation characteristics of the proposed CP-EBG structure are measured using the asymmetric microstrip line method. A cylindrical DRA incorporating the developed CP-EBG structure is then designed and its performance is evaluated with and without the CP-EBG around the 60 GHz bandwidth. Measurements show a significant improvement in the antenna radiation characteristics when it is surrounded by CP-EBG structure. A gain increase of up to 3.2 dBi is obtained while preserving the gain flatness over the suggested bandwidth ( ± 0.7 dB). An additional backlobe suppression of up to 6.5 dBi is achieved. Moreover, radiation toward substrate edges is significantly reduced.

Parametric Performance Analysis of Patch Antenna Using EBG Substrate

In recent years, microstrip antennas becomevery popular because of their interesting advantages of low cost, low profile, light weight, easy fabrication andease of analysis. Electromagnetic Band Gap (EBG) substrate is used as a part of antenna structureto improve the performanceof the patch antenna. Usually, the performance of a patch antenna depends on the parameters such as Return Loss (RL) , Bandwidth (BW), Gain, and Directivity. In this paper, we propose a rectangular microstrip patch antenna with EBG substrates of different EBG patch width and analysis the performance of the proposed antennacompare with a conventional patch antennausing the same physical dimensionusing HFSS simulator. Here we show four analyses of our designed antenna and compare with the conventional microstippatch antenna. Comparison results show that, the performances of our proposed schemes arebetter comparing the conventional patch antenna.

SAR AND RADIATION CHARACTERISTICS OF A DIPOLE ANTENNA ABOVE DIFFERENTFINITE EBG SUBSTRATESIN THE PRESENCE OF A REALISTICHEAD MODEL IN THE 3.5 GHZ BAND

This study investigates the performance of a dipole antenna above electromagnetic band gap (EBG) substrates with difierent number of patches to realize a low speciflc absorption rate (SAR) antenna for a 4G wireless communications system (3.5GHz band). A cubic head model is used for the initial analysis to estimate the radiation characteristics and the SAR of the antenna. Computational results have shown that the antenna above an EBG substrate could provide a maximum reduction of 81% in the SAR and a radiation e-ciency improvement of 10% when compared with the antenna above a perfect electric conductor (PEC) ground plane. However, the antenna above an EBG substrate with a lower number of patches results in a higher resonance frequency and cannot provide su-cient SAR reduction In both the cubic and realistic head models, a similar tendency was observed in the SAR reduction capability of the antenna above the EBG substrates when compared with the antenna above the PEC ground plane. For the realistic head model, the SARs of the dipole above EBG substrates with 20 or 24 EBG patches can be reduced by 16% when compared to the case with 12 or 16 EBG patches. The variability of the SAR in the operating frequency band (jS11j > 10dB) of the antenna is 5{35% for difierent EBG substrates.

Analytical model for electromagnetic bandgap structures embedded in power/ground plane

AbstractThis study presents an analytical model to calculate the stop band of the electromagnetic bandgap (EBG) materials embedded in PCB power/ground plane to mitigate power/ground plane noise. By treating the EBG structure as lumped elements at each unit, the currents flowing through the EBG patches may be analytically computed for the modes in the power/ground plane. An analytical model is derived based on the superposition of the local EBG currents' effects on the modal field distribution in the substrate. Comparisons with measurements are also presented to validate the derived model. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 835–838, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22296

Ultra-Wideband Mitigation of Simultaneous Switching Noise Using Novel Planar Electromagnetic Bandgap Structures

A novel design of power/ground plane with planar electromagnetic bandgap (EBG) structures for suppressing simultaneous switching noise (SSN) is presented. The novel design is based on using meander lines to increase the effective inductance of EBG patches. A super cell EBG structure, comprising two different topologies on the same board, is proposed to extend the lower edge of the band. Both novel designs proposed here are validated experimentally. A -28dB suppression bandwidth starting at 250MHz and extending to 12GHz and beyond is achieved

Cavity Resonance Suppression in Power Delivery Systems Using Electromagnetic Band Gap Structures

The utilization of electromagnetic band gap (EBG) structures is a new and promising approach in plane pair noise cavity resonance suppression. In this paper, EBG/plane pair structures are studied with full-wave methods and results are experimentally verified. A new equivalent circuit modeling approach of characterizing the frequency behavior of the entire EBG/plane pair structure is presented. The equivalent circuit of the unit cell is proposed and the procedure to extract circuit parameters is described. The influence of EBG patch parameters on the band gap characteristics is quantified and the results provide some design rules to circuit designers. Examples of applications of EBG structures to power/ground plane noise suppression are given.

35GHZ Patch Antenna Array Based on the Electromagnetic Band?Gap Structure

The electromagnetic band‐gap (EBG) structure, also called photonic band‐gap structure, consisted by triangular arrays of air columns on the dielectric structure is designed and studied by using the FDTD method. According to the simulated and measured results, the EBG structure effectively suppressing surface wave for TE and TM modes is designed. The optimized EBG structure is presented.The proposed EBG structure is applied to the four‐element microstrip patch array antenna. As results of simulation and measurements, the impedance bandwidth and the gain of proposed EBG patch array antenna are improved.

Reflection phase characterizations of the EBG ground plane for low profile wire antenna applications

Mushroom-like electromagnetic band-gap (EBG) structures exhibit unique electromagnetic properties that have led to a wide range of electromagnetic device applications. This paper focuses on the reflection phase feature of EBG surfaces: when plane waves normally illuminate an EBG structure, the phase of the reflected field changes continuously from 180/spl deg/ to -180/spl deg/ versus frequency. One important application of this feature is that one can replace a conventional perfect electric conductor (PEC) ground plane with an EBG ground plane for a low profile wire antenna design. For this design, the operational frequency band of an EBG structure is defined as the frequency region within which a low profile wire antenna radiates efficiently, namely, having a good return loss and radiation patterns. The operational frequency band is the overlap of the input-match frequency band and the surface-wave frequency bandgap. It is revealed that the reflection phase curve can be used to identify the input-match frequency band inside of which a low profile wire antenna exhibits a good return loss. The surface-wave frequency bandgap of the EBG surface that helps improve radiation patterns is very close to its input-match frequency band, resulting in an effective operational frequency band. In contrast, a thin grounded slab cannot work efficiently as a ground plane for low profile wire antennas because its surface-wave frequency bandgap and input-match frequency band do not overlap. Parametric studies have been performed to obtain design guidelines for EBG ground planes. Two novel EBG ground planes with interesting electromagnetic features are also presented. The rectangular patch EBG ground plane has a polarization dependent reflection phase and the slotted patch EBG ground plane shows a compact size.