Mushroom-like Electromagnetic Band Gap Research Articles

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.

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.

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.

Mushroom like EBG to improve the Gain and Broadband of Patch Antenna for Ku-Band Satellite Application

In order to increase the gain of the patch antenna , a Mushroom-like EBG(Electromagnetic Band Gap ) structure is used . EBG structures enhance the patch antenna’s characteristics of directivity, bandwidth and efficiency . Initially, we determined frequency band gap characteristics of mushroom-like EBG unit cell value by using ANSYS software . The periodic arrangement of such mushroom-like EBG structure was not limited by any inter connecting microstrip lines . Different patches of similar configuration were arranged in a pattern to better improvement in an antenna performance . The final design shows an effective increase in Gain . The current distributions on those metal patches are nearly uniform, allowing for substantial gains throughout the working bandwidth. Keywords—EBG , mushroom-like EBG, ANSYS software ,Broadband .

Design and Enhancement of Microstrip Patch Antenna Utilizing Mushroom Like-EBG for 5G Communications

Besides the considerable rise in wireless network usage and network-connected apps, this causes congestion, leading to a drop in data transmission speed. As a result of their high bandwidth availability and high data transfer speed, network operators recommended switching to higher frequencies. In communications via distance, the antenna plays a significant role in the transmission of the electrical radiated signal or the receiving of the electromagnetic signal. Many antennas can be utilized, one of which is the Microstrip Patch (MP) antenna. These antennas are very prevalent for their ease of configuration and design. On the other hand, it suffers from a lack of gain. In this research article, an MP antenna and MP antenna array are introduced and designed based on computer simulation technology antenna modelling software for 5G based-28 GHz applications. In order to optimise and enhance the simulated MP antenna parameters, the mushroom-like Electromagnetic Band Gap (EBG) is embedded with the MP antenna and MP antenna array to eliminate the presence of the surface waves that affecting negatively on the antenna gain. According to the simulation results, the gain is enhanced after utilising the mushroom-like EBG to be 6.48 dBi and significantly after applying the array configuration to be 11.9 dBi.

Wideband and dual-band antennas with band-notched using electromagnetic band-gap structure

This paper presents a single-element microstrip spade-shaped patch antennas with a partial ground plane, integrated with an electromagnetic band-gap (EBG) structure, and fed with a microstrip feedline to achieve wideband, dual-band and band-notched characteristic. Two similar mushroom-like EBG structures built into the wideband antenna were used to suppress a specific band, resulting in dual-band. The wide-band antenna achieved a broad bandwidth of 9GHz from 5-14GHz, with a maximum gain of 6.8dBi. Based on the simulation and measured results, the wide-band antenna offers 89% fractional bandwidth for a voltage standing wave ratio less than 2 (VSWR < 2). The EBG provides a band-notch with a bandwidth 3GHz from 8-11GHz, leaving dual-band with bandwidths of 2GHz and 1.5GHz centred at 7GHz and 11GHz, respectively. Surface current distribution and parametric studies were conducted to better understand the behaviour and influence of the EBG parameters. The simulation results were validated through experimental measurement, and both agreed well. The antennas could be used for 5G wireless communication and filtering.

Design and SAR Analysis of a Dual Band Wearable Antenna for WLAN Applications

This paper presents the design of three types of dual band (2.5 & 5.2 GHz) wearable microstrip patch antennas. The first one is based on a conventional ground plane, whereas the other two antennas are based on two different types of two-dimensional electromagnetic band gap (EBG) structures. The design of these two different dual-band EBG structures using wearable substrates incorporates several factors in order to improve the performance of the proposed conventional ground plane (dual band) wearable antenna. The second EBG with plus-shaped slots is about 22.7% more compact in size relative to the designed mushroom-like EBG. Subsequently, we have demonstrated that the mushroom-like EBG and the EBG with plus-shaped slots improve the bandwidth by 5.2 MHz and 7.9 MHz at lower resonance frequencies and by 33.6 MHz and 16.7 MHz at higher resonance frequencies, respectively. Furthermore, improvements in gain of 4.33% and 16.5% at a frequency of 2.5 GHz and improvements in gain of 30.43% and 4.57% at 5.2 GHz have been achieved by using the mushroom-like EBG and EBG with plus-shaped slots, respectively. The operation of the conventional ground plane antenna is investigated under different bending conditions, such as wrapped around different rounded body parts. The proposed conventional ground plane antenna is placed over a three-layered (flat body phantom (chest)) and four-layered (rounded body parts) tissue models, and a thorough SAR analysis has been performed. It is concluded that the proposed antenna reduces SAR effects (<2 W/kg) on the human body, thereby making it useful for numerous critical wearable applications.

Design of an omnidirectional transmit/receive antenna pair using mushroom‐like electromagnetic band‐gap structure

This paper presents a transmit-receive (T/R) antenna pair with omnidirectional and broadband radiation performance. The proposed antenna combines a patch with mushroom-like electromagnetic band-gap (EBG) structures. The mushroom structures are utilized to enhance the radiation characteristics such as impedance bandwidth, directivity, and gain. Two T/R antennas with 3 × 3 and 5 × 5 arrays working in K-band are designed and fabricated, the transmit (TX) and receive (RX) antennas are printed on a single-layer grounded dielectric substrate. Both the TX and RX antennas consist of an array of mushroom-like EBG structures around the monopole microstrip antenna, which is loaded with four stubs and fed by a 50 Ω coaxial probe. The dimensions of the fabricated prototype 3 × 3 array antenna are 3.58 λ 0 × 1.61 λ 0 ( λ 0 -the wavelength in free space at 24 GHz). The TX/RX measured impedance bandwidth ( ∣ S 11 ∣ < −10 dB) are 9.58% (23.6 ~ 25.9 GHz), 12.08% (22.8 ~ 25.7 GHz), respectively. The measured peak gain is 3.45 dBi at 24.8 GHz. For the 5 × 5 array antenna, the aperture size is 5.58 λ 0 × 2.61 λ 0 . The measured impedance bandwidth ( ∣ S 11 ∣ < −10 dB) is 9.17% (23.65 ~ 25.85 GHz) and 12.71% (22.65 ~ 25.7 GHz) for the TX and RX, respectively. The measured peak gain increases by nearly 2 dB. Measurement results show that both antennas have a TX/RX isolation level better than 20 dB and achieve monopole-like omnidirectional patterns over its operating frequency band.

Wideband Low-Profile Dual-Polarized Antenna Based on a Gain-Enhanced EBG Reflector

This letter proposed a wideband dual-polarized antenna based on a gain-enhanced electromagnetic bandgap (EBG) reflector. The proposed reflector is studied with a purpose of mitigating the problem of deformed radiation patterns for a mushroom-like EBG reflector backed wideband crossed-dipole antenna, which is caused by undesirable surface current distribution on the patches of the EBG reflector. Introducing the gain-enhanced EBG reflector raises the average broadside gain of the antenna from 4.27 to 8.03 dBi. The antenna is designed to have a working bandwidth of 42.89% (3.04–4.70 GHz) for both ports, with a profile height of 6.26 mm.

Monopole antenna integrated cavity resonator for microwave imaging

We present a system that displays an image of any metal structure in a scene by the use of microwave radiation from a cavity resonator in a 10-GHz frequency band. An 80 mm × 80 mm mushroom-like electromagnetic band gap (EBG) structure was arranged, designed, analyzed, and integrated with an X band monopole antenna and the designed EBG monopole antenna has ∼2-GHz bandwidth. Meanwhile, a cubic cavity resonator is constructed and an EBG grounded monopole antenna is located on one wall of the cavity resonator to create a narrow band radiation. The formed narrow band radiation from the cavity resonator reaches to the metal structure located in the scene. Backscattered radiation collected by a 8 to 12 GHz waveguide receiver that is located near the cavity to scan the whole scene and sweep the waveguide throughout the resonator plane performs to gather various transmission values from a scene. These various transmissions from the cavity resonator antenna to the waveguide receiver were used for imaging. In addition, tunability of the designed EBG structure is studied and presented. The designed structure has advantages such as easy design and fabrication, high accuracy performance, and compatibility to the other frequency regimes. In addition, the designed EBG plane is based on RLC circuit theory, which enables us to understand the antenna performance and EBG structure. This system can be integrated with various areas, such as medical imaging, military applications, weapon detections, security imaging purposes, stealth technology, and other appropriate applications.

Resonator Rectenna Design Based on Metamaterials for Low-RF Energy Harvesting

In this paper, the design of a resonator rectenna, based on metamaterials and capable of harvesting radio-frequency energy at 2.45 GHz to power any low-power devices, is presented. The proposed design uses a simple and inexpensive circuit consisting of a microstrip patch antenna with a mushroom-like electromagnetic band gap (EBG), partially reflective surface (PRS) structure, rectifier circuit, voltage multiplier circuit, and 2.45 GHz Wi-Fi module. The mushroom-like EBG sheet was fabricated on an FR4 substrate surrounding the conventional patch antenna to suppress surface waves so as to enhance the antenna performance. Furthermore, the antenna performance was improved more by utilizing the slotted I-shaped structure as a superstrate called a PRS surface. The enhancement occurred via the reflection of the transmitted power. The proposed rectenna achieved a maximum directive gain of 11.62 dBi covering the industrial, scientific, and medical radio band of 2.40–2.48 GHz. A Wi-Fi 4231 access point transmitted signals in the 2.45 GHz band. The rectenna, located 45 anticlockwise relative to the access point, could achieve a maximum power of 0.53 μW. In this study, the rectenna was fully characterized and charged to low-power devices.

Two Novel Meander-Perforated Plane EBG Structures For 5G Applications

With the advance of 5G network, antennas are required to meet better performance as it’s the key element of 5G network. Meta-surface structure has been demonstrated to be an effective method to improve the performances of an antenna. Whereas, most of the meta-surface structures cannot be applied to 5G applications properly according to the recent research. In this paper, we propose two novel meander-perforated plane (MPP) electromagnetic bandgap (EBG) structures which are named TMPP-EBG and GMPP-EBG. The meander-shape slot of TMPP and GMPP is etched on the top and ground layer respectively. The two novel MPP-EBG structures can be applied to millimeter-wave 5G spectrum from 24GHz to 28GHz. Compared with the conventional mushroom-like EBG structure, the simulated results presented that TMPP-EBG enhances the bandwidth of S21 from 1GHz to 2.5GHz with the same size and GMPP-EBG achieves 14% size reduction with the same resonant frequency.

Electromagnetic Absorbing Materials

Electromagnetic absorbing materials can be classified into: conventional absorbers, metamaterial absorbers , and reconfigurable absorbers. This paper includes a short survey on these types and there applications. It also includes the design of a thin electromagnetic absorber. The absorber is based on mushroom-like electromagnetic band gap structure with square patches. A simple procedure is developed to design the absorber. The design is checked by simulation using HFSS package. The effect of changing dimensions of the structure on absorption is evaluated. The results of the parametric study were used to trim the design and get more accurate dimensions of the structure.

A Novel Design of Radiation Pattern-Reconfigurable Antenna System for Millimeter-Wave 5G Applications

In this article, a novel design of dielectric resonator antenna (DRA) with a reconfigurable radiation pattern capability is presented. Reconfigurability in the azimuth plane is achieved by symmetrically placing six electromagnetic bandgap (EBG) sectors around the DRA. Each sector is composed of 26 circular-shaped mushroom-like EBG unit cell. In order to achieve 360° pattern reconfigurability with a minimum number of diodes, a network of metallic veins printed on a conductor-backed dielectric slab is used to group and connect the vias in each EBG sector. In addition, a switching p-i-n diode is integrated to the circuit to control the beam steering in the entire azimuth plane toward the respective desired sector by turning on and off the diode. Sixty GHz DRA prototype incorporating the EBG switching circuit is fabricated and tested. Results show 360° pattern reconfigurability in the azimuth plane, with a realized gain of 4.2 dBi, and less than −16 dB impedance matching level over the desired bandwidth are achieved.

Suppression of Wideband Simultaneous Switching Noise Through Application of a Partial Electromagnetic Band-Gap Structure in Multilayer Printed Circuit Boards

Adding mushroom-like electromagnetic band-gap (EBG) structures to split power planes can produce wideband suppression of ground bounce noise in high-speed printed circuit boards. Practical equations are used to estimate the stop-band performance of EBG structures within parallel power planes. In this article, a mushroom-like EBG and power-bus structure are derived using the modified nodal analysis (MNA) method. Equations calculated using the MNA method are easily programmable. The partial EBG structures developed in this article can suppress noise from electromagnetic (EM) interference within parallel plates in the power bus. Several examples below show that similar results can be obtained in measurements, in EM simulations software, and in derived equations. The proposed structure enhanced the suppression of simultaneous switching noise coupling (≤-40 dB) within the range of 260 MHz to 10 GHz.

Radiation control of microstrip patch antenna by using electromagnetic band gap

In this paper, two compact electromagnetic band gap (EBG) antennas are proposed by combining a rectangular antenna with a mushroom-like EBG structure and with a novel triple side-slotted EBG (TSSEBG). Both prototype antennas can scan the main beam in the elevation (E) (−20° < φ < 20°), (−17° < φ < 17°) and horizontal (H) (−18° < θ < 18°), (−15° < θ < 15°) planes, respectively. The main beam scanning was conducted by using band-stop and band-pass properties. The band-stop property was achieved by connecting the vias to the ground plane of the antenna, whereas the band-pass property was realized by disconnecting the same vias, thereby yielding the beam steering into the pass-band sector. Unlike usual beam steering, this technique does not suffer from gain degradation, and the gain of the main lobe is approximately stable for the steering angles. The antenna performance was enhanced due to suppress surface waves. Moreover, the number of vias was reduced significantly in the proposed TSSEBG instead of the mushroom-like EBG. The compact EBG and TSSEBG antennas have directivity (10 and 10.5) dBi, gain (9.86 and 10.16) dB, and efficiencies of 96.5% and 93%, respectively, with the operating frequency at 6 GHz.

A miniaturized dual band EBG unit cell for UWB antennas with high selective notching

AbstractA high selective dual band and miniaturized electromagnetic band gap (EBG) unit cell is presented in this paper. The analysis and characterization of the new cell are explained. The modified compact EBG unit cell is based on cutting two inverted U-shaped slots inside the typical mushroom-like EBG. The modified EBG has a 70% size reduction. The dual-band functionality of the structure is confirmed by applying it in a dual-notch ultra-wideband antenna (3.1–10.6 GHz), and the notch frequencies are 5.2 and 5.8 GHz. The dual-band functionality has advantages of a highly selective bandpass between them. The antenna can suppress interference frequencies in less than 100 MHz bandwidth without affecting the antenna performance in the whole bandwidth. Presented results are addressed in terms of circuit modeling, 3D full-wave simulations, and measurements.

Radiation pattern control of microstrip antenna in elevation and azimuth planes using EBG and pin diode.

An important issue in wireless communication systems, which is related to the antenna gain degradation in case of changing the main direction of the antenna radiation pattern, this variation is not approval in many communications systems. In order to improve antenna radiation performances, Electromagnetic band gap (EBG) - antenna with radiation pattern control capability is presented. Mushroom-like EBG structure for suppressing surface waves has been combined, with the switching diode to produce the radiation pattern control with improving antenna characteristics of gain, directivity and efficiency. EBG of several cells are surrounded the patch antenna and placed symmetrically for the two opposite sides, generating different radiation patterns control ability in both the elevation (E) (-20° &amp;lt; φ &amp;lt; 20°) and azimuth (Z) planes (−18° &amp;lt; θ &amp;lt; 18°). At the ground plane of antenna the diodes have been switched ON and OFF states, the EBG sector properties in stop band (connecting vias) and pass band (disconnecting vias) are altered. Using CST Microwave Studio (CST MWS) the results show the flexibility in radiation pattern control for the Z and E planes using only four diodes. Antenna directivity of 10 dBi, gain 9.86 dB and efficiency 96.5% at the operating frequency of 6 GHz, more results for all direction has been stated in Table1. Significantly, unlike a conventional beam steering, this method does not suffering from gain degradation and the main lobe gain is approximately constant for all steerig angles.

Wideband Beam Steering Antenna Array of Printed Cavity-Backed Elements With Integrated EBG Structure

The letter concerns the design of a wideband printed antenna array element based on a cavity-backed patch radiator with an incorporated U-slot. An additional 2 × 3 mushroom-like electromagnetic bandgap structure is introduced in the E-plane in close proximity to the patch element on the same single-layer substrate. The proposed array unit cell design is optimized for operation in the 12% relative bandwidth in C-band and the 80° conical beam steering sector. Both simulated and experimental data demonstrate considerable wideband beam steering performance improvement compared to the basic design (without isolating structure) characteristics, provided by achieved array elements decoupling. Research results predict for the 12% relative bandwidth broadside reflection coefficient magnitude |Γ| ≤ 0.3, and maximum for the 80° conical beam steering sector |Γ| ≤ 0.37.

Wideband Linearly-Polarized and Circularly-Polarized Aperture-Coupled Magneto-Electric Dipole Antennas Fed by Microstrip Line With Electromagnetic Bandgap Surface

Wideband aperture-coupled magneto-electric (ME) dipole antennas fed by microstrip line are proposed in this paper. The aperture-coupled microstrip-line-fed method was utilized in the proposed configuration to replace the conventional Γ-shaped probe to excite the ME dipole antenna. Particularly, a printed mushroom-like electromagnetic bandgap (EBG) surface was mounted below the microstrip line to effectively eliminate the back radiation caused by the aperture on the ground plane. Two configurations of ME dipole antennas with linear polarization (LP) and circular polarization (CP) have been proposed for adequately studying the effect of the EBG surface. Both the simulation and measurement of the two prototypes had been carried out for verification. Based on the measured results, wide impedance bandwidth (SWR <; 2) of 54.9% and 58% can be obtained for both the proposed LP and CP ME dipole antennas, respectively. Besides, the performances of the stable broadside radiation pattern with the enhanced front-to-back ratio (FBR) can also be achieved for both configurations.