Defected Ground Plane Research Articles

Retraction notice: Kuznets curve with parabola-shaped ultra-wideband antenna with defected ground plane for communications

Retraction notice: Kuznets curve with parabola-shaped ultra-wideband antenna with defected ground plane for communications

Compact Defected Ground Structure Microstrip Patch Antenna for Wi-Fi Applications

In recent years microstrip patch antennas having minute size is an exciting topic for many researchers and design engineers. In this paper a novel miniaturized microstrip patch antenna for Wi-Fi applications is proposed. The concept of defected ground plane (DGS) is used for achieving miniaturization. The prototype is designed and analyzed by CST Microwave Studio. Low cost FR-4 substrate having thickness of 0.8 mm is used for the design of the antenna. The antenna is having compact size of 16 × 17 mm2. The simulated results demonstrate that the antenna has bandwidth of 2.02% (49 MHz) with -41.46 dB reflection coefficient at resonating frequency. The antenna has bidirectional radiation pattern. The proposed design provides a size reduction of 75.46% in comparison to conventional patch. The proposed antenna is having compact size and is low cost which makes it a suitable candidate for 2.4 GHz Wi-Fi band.

Compact circular microstrip 1:4 power divider/combiner with defected ground plane

This letter presents a methodology for the design of high-performance miniaturized Circular Power Dividers (CPDs) for wideband applications. To accomplish this objective, annular slots are strategically incorporated into patch and the ground plane of CPDs. This, in turn, increases the effective path length of the surface current flowing across the patch. This yields miniaturization, improved impedance matching, reduced insertion loss and increased isolation over a larger bandwidth. A mathematical model is developed for the design of the proposed configuration called Circular power dividers with Defected Ground Plane(CDGP). The presented model has been verified through various simulations and practical measurements. By implementing this approach, a substantial miniaturization of approximately 83% and more than threefold increase in bandwidth has been achieved when compared with non-slotted CPDs. Moreover, there is improvement in insertion loss, isolation, and return loss as well. There is good agreement between the mathematical model, simulation results and measured parameters.

Circularly polarized implantable MIMO antenna for skin, brain and heart implantation with wide axial ratio bandwidth

SummaryA unique MIMO antenna with circular polarization characteristics that works similarly for skin, brain and heart phantoms has been proposed in this paper. The twin rectangular X‐shaped slot that serves as the basic structure of the proposed antenna is entirely planar and low‐profile but has a defective ground plane. For three different phantoms, the proposed antenna resonates at 2.4–2.45 GHz ISM band. With a dimension of , the antenna exhibits compactness. Rogers RT/duroid 6010 substrate material has been used to fabricate the antenna in order to validate the designed antenna structure. Utilizing the high dielectric material for both substrate and superstrate, both skin‐mimicking gel and minced hog meat were employed in the experiment setup at 2.45 GHz ISM band. At ISM band, −28.3 dBi has been observed has realized peak gain. The obtained fractional bandwidth (FBW) and Axial Ratio Bandwidth (ARBW) values are 30.67% and 45%, respectively. Also, the maximum specific absorption rate (SAR) values are found to be in the acceptable limit regulated by IEEE.

A Compact Highly Isolated Four-Element Antenna System for Ultra-Wideband Applications

A small, orthogonally polarized, ultra-wideband (UWB), four-port multiple-input multiple-output (MIMO) printed antenna is presented in this study. The envisioned antenna is built up of four microstrip fractal-based circular patch elements, each of which is fed by a microstrip line with a 50-ohm impedance. The use of a defective ground plane allows for the ultra-wideband frequency response to be obtained. In order to achieve maximal isolation, the amount of surface current that flow between the antenna’s four components is limited by arranging radiating elements orthogonally. The four-port MIMO system is printed on a FR4 substrate with a loss tangent of 0.02 and an overall dimension of 20 × 30 × 1.6 mm3. A port-to-port isolation of less than 25 dB was achieved as a consequence of this orthogonal orientation of antenna elements, and the impedance bandwidth is achieved up to 158% (3.1–12 GHz). The suggested ultra-wideband multiple-input multiple-output (UWB-MIMO) antenna achieved a maximum gain of 8 dBi over the operational frequency range (3.1–12 GHz); the findings that were measured and those that were simulated accord with one another rather well. The findings also give an overall strong diversity performance, with the ECC < 0.25, DG > 9.9, and CCL < 0.2 values all being within acceptable ranges.

Design of defective ground plane modified microstrip patch antenna for ultra-wideband applications

Design of defective ground plane modified microstrip patch antenna for ultra-wideband applications

Eight-Element Dual-Band Multiple-Input Multiple-Output Mobile Phone Antenna for 5G and Wireless Local Area Network Applications.

This paper proposes an eight-element dual-band multiple-input multiple-output (MIMO) antenna that operates in the fifth generation (5G), n78 (3400-3600 MHz), and WLAN (5275-5850 MHz) bands to accommodate the usage scenarios of 5G mobile phones. The eight antenna elements are printed on two long frames, which significantly reduce the usage of the internal space of the mobile phone. Each antenna element is printed on both surfaces of one frame, which consists of a radiator on the internal surface and a defected ground plane on the outer surface. The radiator is a rectangular ring fed by a 50 Ω microstrip line which is printed on the top surface of the system board. A parasitic unit is printed on the outer surface of each frame, which is composed of an inverted H-shaped and four L-shaped patches. Each parasitic unit is connected to the internal surface of the frames through a via, and then it is connected to a 1.5 mm wide microstrip line on the top surface of the system board, which is connected to the ground plane on the bottom surface of the system board by a via. Four L-shaped slots, four rectangular slots, and four U-shaped slots are etched onto the system board, which provides good isolation between the antenna elements. Two merged rectangular rings are printed on the center of each frame, which improves the isolation further. The return loss is better than 6 dB, and the isolation between the units is better than 15 dB in the required working frequency bands. In addition, the use of a defected ground structure not only makes the antenna element obtain better isolation but also improves the overall working efficiency. The measurement results show that the proposed MIMO antenna structure can be an ideal solution for 5G and WLAN applications.

An antenna array utilizing slotted conductive slab: inspired by metasurface and defected ground plane techniques for flexible electronics and sensors operating in the millimeter-wave and terahertz spectrum

This paper describes an innovative design of an antenna array that is metamaterial inspired using sub-wavelength slots and defected ground structure (DGS) for operation over millimeter-wave and terahertz (THz) spectrum. The proposed antenna array consists of a 2 × 4 array of conductive boxes on which are implemented rectangular slots. The presence of dielectric slots introduces resonant modes within the structure. These resonant modes result in enhancing the electromagnetic fields within the slots, which radiate energy into free space. The resonant frequencies and radiation patterns depend on the specific geometry of the slots and the dielectric properties. The antenna array is excited through a single microstrip line. The radiating elements in the array are interconnected to each other with a microstrip line. Unwanted mutual coupling between the radiating elements can degrade the performance of the antenna. This was mitigated by defecting the ground plane with rectangular slots. It is shown that this technique can enhance the array’s reflection coefficient over a wider bandwidth. The array was constructed on polyimide substrate having dielectric constant of 3.5 and thickness of 20 μm. The design was modelled, and its performance verified using an industry standard electromagnetic package by CST Studio Suite. The proposed array antenna has dimensions of 20 × 10 mm2 and operates between 80 and 200 GHz for radiation gain better than 4 dBi and efficiency above 55%. The peak radiation gain and efficiency are 7.5 dBi and 75% at 91 GHz, respectively. The operational frequency range of the array corresponds to a fractional bandwidth of 85.71%.

A highly decoupled flexible 4-element MIMO antenna with band notched characteristics for ultra wide-band wearable applications

In this paper, a flexible, planar, and low profile ultra-wideband multi element textile antenna is presented. The antenna comprises four tree-shaped elemental structures. A defected ground plane and four defected feed lines are utilized to achieve higher port isolation with band notch characteristics. The proposed antenna uses an integrated slotted ring type stub with rectangular line extended over two sides. It is connected to the two sides of the partial ground. The antenna band width is from 3.18 to 4.60 GHz and 8.89 to 12 GHz with notch characteristics over full WLAN (2.4–2.485 GHz, 5.15–5.85 GHz), C-band uplink (5.925–6.425 GHz), GEOSAT LNB (7.25–7.75 GHz), and ITU (7.75–8.5 GHz) application bands. Moreover, a healthier isolation of about 20.5 dB is realized concerning between any two ports. A prototype of the suggested antenna is fruitfully fabricated and required measurement is done. Several diversity parameters, radiation characteristics, antenna gain etc. are investigated. Both the simulated and experimental outcomes direct the proposed antenna as a good MIMO contender. From the investigated notch properties it is found the antenna can be realistic in UWB wireless application to prevent the interference from the specified notch frequency band.

Machine learning with A MIMO Antenna for Wireless Communication Systems

Multiple-input multiple-output (MIMO) antenna is a technology that uses multiple antennas at both the transmitter and receiver to improve the performance of wireless communication systems. One of the challenges in designing MIMO antennas is to reduce the complexity of the antenna array, while still maintaining good performance. One way to reduce complexity is to use shared antennas. Shared antennas are antennas that are used by multiple elements of the MIMO array. This can reduce the number of required antennas and simplify the design of the antenna array. The B-shape of the MIMO antenna by using CST program can also be used to reduce complexity. For example, hexagonal MIMO antennas have been shown to have good performance and can be implemented with a simple design. Additionally, the use of defected ground planes (DGPs) can be used to improve the isolation between the elements of a MIMO antenna array, which can also reduce complexity. The design of MIMO antennas is a complex and challenging task. However, by using shared antennas and other design techniques and AI, it is possible to reduce the complexity of MIMO antennas while still maintaining good performance.

Design and analysis of ultra-wideband four-port MIMO antenna with DGS as decoupling structure for THz applications

The growing demand for high-speed communication has resulted in developing terahertz (THz) antennas that operate at high-frequency, high-speed, and high data rates. An ultra-broadband functioning four port THz multiple input and multiple output (MIMO) antenna with a defective ground plane as a decoupling structure is proposed in this study. A rectangular metallic patch was changed by integrating parasitic components onto the radiator with the lowered ground plane on a polyamide substrate to obtain the ultra wideband THz frequency operating antenna. The designed THz antenna has been transformed into a MIMO antenna by replicating horizontally and vertically with the separation of 0.08 λ and 0.01 λ, respectively (λ computed at 2 THz). The proposed THz MIMO antenna operates in the 2–10.7 THz frequency range and has an overall substrate dimension of 40 μm x 46 μm × 2 μm. The proposed antenna equivalent circuit is designed to validate the impedance bandwidth of the antenna. The designed THz MIMO antenna has isolation better than 20 dB across the impedance bandwidth. The isolation enhancement is achieved by creating alternate current channels through the defected ground structure of the antenna. The proposed THz MIMO antenna's MIMO diversity features are studied and determined to be ECC < 0.001, DG is about 10 dB, TARC < -10 dB, MEG < -3 dB, and CCL < 0.2 bps/Hz over the antenna's operational frequency.

A compact bent microstrip-based wideband millimeter wave MIMO antenna for 5G applications

Abstract This paper proposes a wideband four-element multiple-input multiple-output (MIMO) antenna operating in the millimeter-wave frequency band for 5G communications from 24.37–39.44 and 45.09–50.62 GHz. The antenna design has been realized using Rogers 5880 substrate and consists of a T-shaped strip that is attached to the top of a 50 Ω feeding line. Two microstrip lines are affixed at the terminal points of T-shaped strip and bent toward the feeding structure. These bent strip lines are then extended by joining two additional L-shaped microstrip lines. On the back, there is a partial defective ground plane featuring a rectangular slot and a thin strip line located at its center. The dimensions of the proposed single element and MIMO antenna are 0.933λ × 0.933λ × 0.024λ and 1.865λ × 1.865λ × 0.024λ, respectively (at 28 GHz), while the edge-to-edge distance between the radiation elements of the MIMO antenna is 4.0 mm. The design incorporates an efficient passive fan-shaped decoupling structure to decrease coupling between antenna elements. Simulations and experimental results show good agreement with each other. For all resonant frequencies the measured peak gain is greater than 4.85 dBi, radiation efficiency is over 90%, diversity gain is greater than 9.5, ECC is less than 0.025, TARC is less than -10 dB and CCL is below 0.4 bits/s/Hz. The proposed MIMO antenna, with its wide bandwidth, high gain, high inter-port isolation, and high efficiency characteristics, can be used for 5G wireless communication applications.

A Triband Compact Antenna for Wireless Applications

This paper presents the implementation of a triple band microstrip patch antenna based on modified split ring resonator (SRR) and modified complementary split ring resonator (CSRR) as defected ground plane. The antenna is designed in a FR4 substrate of dielectric constant 4.4 with dimensions as 35 mm × 35 mm × 1.6 mm that comprises a total designed antenna volume of 1960 mm3. Multiband operation is introduced in the antenna through multiple resonators that are introduced in the patch. Impedance matching was provided with the help of partial ground plane and modified SRR in patch. The simulation performance of the antenna is verified using high frequency structural simulator (HFSS) software. The designed antenna resonates at 2.8 GHz, 5.8 GHz, and 6.9 GHz for the application requirements of WiMAX, ISM, and Sub-7 GHz wireless communication. The antenna is fabricated as printed circuit board (PCB) format, and its return loss characteristics are measured using a vector network analyser (VNA). The measurement results of the proposed triband antenna are in good agreement with simulated return loss characteristics.

A compact 4 × 4 reconfigurable MIMO antenna design with adjustable suppression of certain frequency bands within the UWB frequency range

This paper introduces a novel 4 × 4 multiple-input multiple-output (MIMO) antenna design with a reconfigurable operating band within the Ultra-Wideband (UWB) range. The antenna consists of four rectangular radiating elements arranged symmetrically and orthogonally on a defected ground plane. The design incorporates switching elements that allow adjustable and reversible suppression of specific bands within the UWB range, enabling the antenna to operate in three different modes: UWB, X-band, and dual-band with sub-6GHz and X-band. Thus, a single UWB antenna can serve as three different antennas, suppressing certain frequencies as required. To mitigate mutual coupling between adjacent antenna elements, four thin stubs are strategically placed at the center of the ground plane, forming a square with open corners. When one of the antenna elements is excited, this structure acts as an insulator, ensuring that the surface current is confined solely to that element and not induced in others. Experimental verification of the proposed design was performed by fabricating and testing the antenna. The results indicated good agreement between simulation and measurement data for various parameters, including S-parameters, radiation patterns, gains, and MIMO parameters such as envelope correlation coefficients (ECC), diversity gain (DG), mean effective gain (MEG), and total active reflection coefficient (TARC).

Rectangular Dual Band Microstrip Patch Antenna with Defected Ground Plane Using CST STUDIO

Abstract: The rectangular dual-band microstrip patch antenna with defected ground plane for wireless communications that operates at 2.4-3.5 GHz. The antenna incorporates a rectangular patch with slot. The dielectric substrate used for antenna is RT Duroid 5880. According to position of etched slot are determined using parametric such as s-parameters and radiation pattern are simulated. The analyses are performed using CST STUDIO SUITE 2019.

An Ultra-Miniaturized High Efficiency Implanted Spiral Antenna for Leadless Cardiac Pacemakers.

This paper presents an ultra-miniaturized implant antenna with a volume of 22.22mm3 in the Medical Implant Communication Service (MICS) frequency band 402-405MHz to be integrated with a leadless cardiac pacemaker. The proposed antenna has a planar spiral geometry with a defective ground plane exhibiting a radiation efficiency of 3.3% in the lossy medium with more than 20dB of improved forward transmission, while the coupling can be further enhanced by adjusting the thickness of the antenna insulation and the antenna size according to the application area. The implanted antenna demonstrates a measured bandwidth of 28MHz, covering beyond the MICS band needs. The proposed circuit model of the antenna describes the different behaviors of the implanted antenna over a wide bandwidth. The antenna interaction within human tissues and the improved behavior of the electrically small antenna are explained in terms of radiation resistance, inductance, and capacitance that are obtained from the circuit model. The results are demonstrated using electromagnetic computations and are validated by the measurement using liquid phantom and animal experiments.

Design of Sub-6 GHz Antenna using Negative Permittivity Metamaterial for 5G Applications

Abstract: The objective of the presented article is to design a compact metamaterial-based dual-band antenna that meets the frequency requirement of 5G. The antenna consists of a Circular Split Ring Resonator structure with a defective ground plane and slots to enhance the bandwidth and gain parameters. Metamaterial-based Microstrip patch antenna produces unique electromagnetic properties that allow us to control over the antenna parameters with a compact size. FR-4 epoxy is used as a substrate its dielectric constant is 4.4 and its loss tangent is 0.02. Dimensions of the antenna are 20 x 12 x 1.6mm3 with a very compact size and cost-effective. The proposed metamaterial-based antenna resonates at dual bands at 3.24GHz and 5.46 GHz respectively. The peak gains at resonant frequencies 3.45GHz and 5.46 GHz are 0.9 dB and 2dB respectively. The proposed antenna shows S-parameters at S11, which is -12.13dB at frequency of 3.45 GHz and -15.165 at a frequency of 5.46 GHz. The proposed antenna can effectively work for WLAN and WiMAX applications. The antenna covers the frequency spectrum from 2 GHz to 8 GHz with a centre frequency of 5 GHz. The proposed antenna is cost-effective

Conformal strip fed circularly polarized defected dielectric resonator antenna (CPDDRA) for 6G applications

In this paper, a broadband circularly polarized (CP) dielectric resonator antenna (DRA) is proposed for terahertz (THz) applications. It consists of a silicon-based defected rectangular dielectric resonator (DR), excited by an asymmetric conformal strip feeding and a defective metallic ground plane. Multiple orthogonal modes are excited using a defective dielectric resonator antenna (DRA) and asymmetric conformal metallic strip to generate circular polarization. The proposed antenna has a fractional bandwidth of 89.5% (2.87–7.52 THz) and an axial ratio bandwidth of 79.2% (2.73–6.31 THz). The proposed antenna provides RHCP radiation pattern in the +z-direction and LHCP in the −z-direction. A peak gain of 6 dB is achieved at 6.9 THz with a compact antenna dimension of 50 × 40 μm2. An equivalent circuit with lumped elements is also presented for the proposed antenna in this paper. The simulated results of the proposed structure are in good agreement with those of equivalent circuit model. The proposed antenna structure fulfils all the requirements of a 6G antenna by operating over a wide terahertz frequency spectrum with circular polarization characteristics, an average peak gain, stable radiation patterns and compact dimensions.

On the design of miniaturized C-shaped antenna based on artificial transmission line loading technique

This article presents an effective miniaturized antenna based on an artificial transmission line loading approach. The proposed antenna is a compact C-shaped radiating element backed by defected ground plane structure and fed by a line transition structure. The antenna is modelled to operate at 2.4 GHz with −32.99 dB return loss and operates from 2.33 GHz to 2.52 GHz with 77.55% fractional bandwidth and a gain value of 2.1 dBi. Equivalent circuits are extracted using the transmission line modelling technique. Moreover, the design has an overall substrate dimension of (20 × 30 × 1.6) mm3, which is suitable for compact wireless devices. Here antenna miniaturization is carried out through patch and ground extensions along with artificial transmission line structures incorporated. The antenna is fabricated and the measured result is in good agreement with the calculated and simulated results. In addition, by transmission line loading in the proposed design, the radiator is configured to work at 2.4 and 3.7 GHz.

Split ring resonator inspired defected ground plane dual operating band antenna for wireless LAN and RFID applications

Defected ground structure (DGS) using an array of the three split ring resonators inspired antenna for the Wireless Local Area Network(WLAN) and RFID sensor is proposed in this manuscript. The complete physical measurement for the proposed antenna is 50 X 40 mm2 (at lower operating frequency). The defected ground plane structure along with the inclusion of the square split ring resonators (SRRs) in the ground plane helps in gain and bandwidth improvement. 1 × 3 split ring resonator array is used to make the existing ground plane to be defected. The cost effective FR – 4 materials is used as a substrate for the fabrication with the standard thickness of 1.6 mm. The resonance frequencies are at 2.4 and 5.8 GHz having the average gain 2.65dBi. The impedance bandwidths for both the frequencies are 5.0 % (2.31 to 2.49 GHz) and 3.9% (4.9 to 6.1 GHz). The dipole and omni directional radiation patterns, overall gain and efficiency of around 75% make the antenna most practically possible for the RFID and WLAN devices.