Ground Plane Size Research Articles

Curved-Pentagonal Planar Monopole Antenna for UHF Television Broadcast Receiving Antenna

A planar monopole antenna is an aerial, which the radiating element is perpendicular to the ground plane. It has five equal curvy sides and works at Ultra High Frequency (UHF) band of terrestrial broadcast 478–806 MHz. The curvy sides are made of five equal trimmed ellipses and separated 72o each ellipse to another, form pentagonal shape. Optimizations are obviously necessary to gain the antenna performance at the desired frequency range. The dimensions to optimize this antenna performance are the length of the sides, the offset of curvature, the antenna height from the ground plane, and the ground plane size. Optimization process is done by simulating the proposed antenna with calculated designs using Computer Simulation Technology (CST) Studio Suite 2015 software. The optimized antenna design then fabricated with a 75 W coaxial line fed, measured, and results: Voltage Standing Wave Ratio (VSWR) range of 1.05–1.28, antenna gain at 600 MHz is 15.33 dBi, elliptical polarized, and omnidirectional. With these features, this antenna should satisfy the requirements of UHF television broadcasting.

A printed wide-beamwidth circularly polarized antenna via two pairs of radiating slots placed in a square contour

A low-profile circularly polarized (CP) slot antenna to achieve a wide axial-ratio (AR) beamwidth is proposed in this paper. The radiating patch consists of two orthogonal pairs of parallel slots etched symmetrically onto a ground plane. Firstly, our theoretical study demonstrates that the CP radiation can be satisfactorily achieved at the broadside, when the vertical and horizontal paired-slots are excited in the same amplitude with 90° phase difference. Secondly, the principle of CP radiation of the proposed antenna on an infinite ground plane is described. Through analyzing the spacing between two parallel slots, the |Eθ| and |Eφ| radiation patterns can be made approximately identical with each other over a large angle range. As such, the slot antenna achieves a wide AR beamwidth. After that, the 3 dB AR beamwidth with respect to the size of a finite ground plane is investigated to constitute a practical CP antenna on a finite ground plane. In final, the proposed CP antenna with a 1–4 probe-to-microstrip feeding network is designed and fabricated on a finite ground plane of a dielectric substrate. Measured results are shown to be in good agreement with the simulated ones about the gain, reflection coefficient, AR bandwidth, and radiation patterns. Most importantly, a wide 3 dB AR beamwidth of 126° and low-profile property with the height of 0.036λ0 are achieved.

Design and Performance Analysis of Microstrip Antenna using different Ground Plane Techniques for WLAN Application

This paper is concentrated on comparison of rectangular patch antenna with different ground plane dimensions i.e. short edge, double ground, triple ground in terms of Bandwidth, Gain, Directivity, VSWR, Reflection coefficient and efficiency performance. The finite ground plane gives rise to diffraction of radiation from the edges of ground plane resulting in modifying of radiation conductance, radiation pattern, and resonant frequency. The substrate used is Flame Retardant4epoxy having dielectric constant of 4.4 and dielectric tangent loss of 0.02. The patch antenna is provided by inset feed line. The design was optimized to obtain the most suitable configuration in terms of desired values of reflection coefficient, bandwidth and Voltage Standing Wave Ratio (VSWR) for antenna with and without modifying on ground plane. These antennas are suitable for WLAN Applications. In this observation, the paper calls for an attention that, the cachet is an amelioration of the 2.4 GHz Industrial, Scientific and Medical (ISM) Band patch antenna is simulated and analysed using HFSS 13.0 and fabricated by photo lithography. The proposed antenna is tested using VNA E5071C.As a result it can be also observed in being when the size of ground plane is increased, the ripples in the main pattern diminishes.

Low Side-Lobe Substrate-Integrated-Waveguide Antenna Array Using Broadband Unequal Feeding Network for Millimeter-Wave Handset Device

A low side-lobe substrate-integrated-waveguide (SIW) antenna array is presented at the 28-GHz band using broadband unequal feeding network for millimeter-wave (mm-wave) handset devices. The ground-plane size of the proposed antenna is fixed to half of the size of the Samsung Galaxy Note 4. The antenna array has been implemented with a multilayer structure created by stacking three substrates and a copper plate. An 8-way SIW feeding network with broadband 4-stage T-junction dividers and a cavity-backed antenna are investigated to obtain broadband performance. The proposed unequal T-junction dividers with phase compensation are introduced and designed for various output ratios. Applying Taylor beam-pattern synthesis in the 8-way SIW feeding network, low side-lobe performance is achieved. The measured result of the fabricated antenna has 2.3 GHz bandwidth within $\text{S}_11\,{ . The fabricated antenna can be performed with a gain up to 13.97 dBi with a low cross-polarization and symmetrical fan beam radiation patterns with low side-lobe levels. Most of the measured results are validated with the simulated results. The proposed antenna array provides low cost, broadband performance, and good radiation performances with low side-lobe levels for mm-wave handset devices.

A Novel High-Gain Printed Antenna Configuration Based on $\text{T}{\text{M}_{12}}$ Mode of Circular Disc

The fundamental (TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> ) mode of a circular patch antenna is generally used for broadside gain applications. However, other TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1m</sub> modes (m = 2,3⋯) also radiate in the broadside direction with high directivities, but are avoided due to the occurrence of sidelobes in the radiation pattern. Here, a simple high-gain disc antenna configuration, using high dielectric constant substrates, operating in the TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sub> mode, is presented. At first, through an analytical study, it is shown that by selecting an appropriate value of the dielectric constant, both high directivity and low sidelobe level (SLL) can be attained. Next, it is demonstrated that the excitation of adjacent modes can be reduced significantly by a proper selection of feed location. For a practical antenna design, it is also shown that the SLL can be further reduced using a finite ground plane size.

The Impact of Substrate Materials to the Design of UWB Modern Antennas

The theory of microstrip antennas has motivated us to design a highly improved gain antenna under this category. It is a microstrip monopole antenna characterized by omni-directional radiation as well as a high radiation gain. A review of different methodologies to designing antennas with broad/ultra-wide band performance for various applications is enriched by our original antenna design. This is an original model analyzed over different substrate materials and finally optimized for the bandwidth of (3.3 - 5.8) GHz just below −10 dB of return loss (RL). The antenna is judged for high gain when the ground plane size is reduced to nearly half that of substrate. The impact of the substrate materials is discussed in this article. The master design tool is Ansoft High Frequency Simulator Structure (HFSS), one of Finite Element Method (FEM) based software tools. The antenna would be printed on a 1.524 mm thick Rogers (RO3003C) substrate; overall size of 33.4 × 33.4 squared millimeters. At the optimal resonance frequency of 3.8 GHz, simulation results perfectly agree with the standards of UWB antennas, with a high radiation gain and impedance matching status.

Low-Profile Magneto-Electric Dipole Antenna

A novel low-profile magneto-electric dipole antenna is proposed and investigated. The antenna utilizes an obtuse-triangular structure to work as a magnetic dipole, which reduces the antenna thickness to ${0.097 {\lambda}_0}$ (where ${{\lambda }_0}$ is the free-space wavelength at the center frequency). A prototype with ground plane size of around $1{{\lambda }_0} \times 1{{\lambda }_0}$ is fabricated and measured. Measurement result shows that the proposed design achieves an impedance bandwidth of 28.2% (1.67–2.22 GHz) for ${{\rm SWR} . A stable gain of $9.2 \pm 1.1 \hbox{dBi}$ is realized. The antenna has a unidirectional radiation pattern with low cross polarization ( $ ) and low back-radiation level ( $ ) across the operating frequency band.

A dual-band antenna design for MIMO LTE applications with reduced ground effects

A dual-band planar long term evolution (LTE) antenna design is initially proposed. The size of this proposed antenna is 40 mm × 15 mm × 0.8 mm, and its structure is meticulously designed to achieve reduce ground effects, so that the ground plane size can be altered without affecting the antenna's performance. The 6-dB impedance bandwidths of both lower and upper operating bands of proposed antenna are 13.1% (695–790 MHz) and 37.6% (2200–3120 MHz), respectively. Minimum radiation efficiencies of up to 56% are also exhibited within the three LTE bands (LTE 700/2300/2600 MHz). This proposed antenna is later used as a two-antenna multiple input multiple output (MIMO) system for laptop computer application, and because of its reduced ground effects, good envelope correlation coefficient (ECC) of less than 0.14 and 0.0022 are measured across the lower and upper operating bands, respectively. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:80–87, 2016.

Enhanced Isolation of a Closely Spaced Four-Element MIMO Antenna System Using Metamaterial Mushroom

A double-layer mushroom structure is proposed to enhance the interelement isolation of a four-element antenna system, wherein four closely positioned substrate-integrated cavity-backed slot (SICBS) antenna elements are configured for multiple-input multiple-output (MIMO) applications. A wall with a double-layer mushroom structure is positioned in between the four antenna elements. An antenna prototype with a ground plane size of ${\mathbf{0}}.{\mathbf{96}}\;{{\mathbf{\lambda }}_{\mathbf{0}}} \times 0.96\;{{\mathbf{\lambda }}_{\mathbf{0}}}$ ( ${{\mathbf{\lambda }}_{\mathbf{0}}}$ is the free space-wavelength at 2.4 GHz) demonstrates an enhanced interelement isolation of 16 dB for parallel-directed antenna element pairs, while the isolation of the orthogonally directed antenna element pairs remains unchanged over the operating bandwidth ( $\vert {{\mathbf{S}}_{{\mathbf{11}}}}\vert ) of 2.396 –2.45 GHz. With the enhanced isolation larger than 42 dB between each antenna element pair, the envelope correlation coefficient (ECC) is lower than 0.02 across the operating bandwidth. The simulated and measured results validate the good MIMO diversity performance of the proposed antenna system.

Design and Implementation of Multiband Internal Antenna for LTE Mobile Handset

In this paper, we proposed a multiband internal antenna for LTE mobile handset that could be used for mobile devices. The proposed antenna has a volume of , ground plane size is , and covers 9 service frequency bands including LTE(Long Term Evolution) band with VSWR(Vlotage Standing Wave Ratio) less than 3. With rapid change of technologies, people wants to include more function into one device. In addition, each country uses different frequency band for traffic service, it is necessary to design multiband antenna for mobile phone since traveling foreign country needs roaming. And if we can cover several services with one antenna, cost and volume needed for antennas are minimized. A HFSS (High Frequency Structure Simulator) of the Ansoft Corporation based on a finite element method is employed to analyze the proposed antenna in the design process and to compare the simulation and experimental results.

Compact multiple‐input multiple‐output antenna with low correlation for ultra‐wide‐band applications

A compact multiple-input multiple-output (MIMO) antenna with a small size of 26 × 55 mm 2 and low correlation has been proposed for the ultra-wide-band (UWB) applications operating over a frequency range of 3.1-12.3 GHz at �10 dB. The MIMO antenna consists of two identical elements each of which has a planar radiator with microstrip-fed over half- sized ground plane. The antenna elements are placed orthogonally to achieve a good isolation between the two input ports. The antenna's characteristics such as the bandwidth, isolation, radiation pattern, peak gain and surface current distributions have been investigated. Moreover, diversity performance in terms of envelope correlation coefficient and mean effective gain has been analysed. Furthermore, a parametric study has been carried out to provide more design information. An arrangement with quad-elements has been designed for MIMO operations, as well. The simulation and measurement results show that the proposed antenna has an impedance bandwidth larger than the frequency range of UWB with low correlation and high diversity performance. The proposed MIMO antenna has been compared in detail with the previous works reported elsewhere in terms of antenna size, geometric complexity, bandwidth, mutual coupling and use of additional structure to obtain more isolation. From this point of views, the antenna is more preferable than other suggestions.

A novel ultrawideband toppled trapezium‐shaped patch antenna with partial ground plane

ABSTRACTIn this article, a new design of ultrawideband microstrip patch antenna is proposed and results are verified experimentally. The printed configuration consists of a toppled trapezium‐shaped radiating patch with finite size ground plane is excited via edge feeding. The antenna offers 114.20% bandwidth when fabricated on a substrate of dielectric constant 3.38. Simulated and experimental reflection characteristics, gain and radiation pattern are presented and discussed. The effect of tilt angles on the antenna characteristics is also studied. The study shows that the proposed antenna is simple in design and easy in feeding to meet the demand of wireless communications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1983–1986, 2015

Effect of Loading Split-Ring Resonators in a Microstrip Antenna Ground Plane

This study presents a new, simple method for improving the front-to-back (F/B) ratio of a microstrip patch antenna (MSA) based on surface wave suppression. The back radiation of the MSA is significantly reduced by using the meandered ground plane edges and placing split-ring resonators (SRRs) in the middle of the meandered slots. By loading SRRs near the center of the meandered ground plane edges, some parts of the diffracted back-lobe power density can be reduced further. Compared to the F/B ratio of a conventional MSA with a full ground plane of the same size, an improved F/B ratio of 18 dB has been achieved experimentally for our proposed MSA.

Design Guidelines Using Characteristic Mode Theory for Improving the Bandwidth of PIFAs

It is well known that the bandwidth for a planar inverted-F antenna (PIFA) changes as the ground plane size changes. To gain insight into what causes bandwidth fluctuations, a process for applying characteristic mode theory to the finite ground plane and feed structure was developed. Four different PIFA designs are then evaluated to show how the modal significance of certain modes on the finite ground plane relate to the bandwidth minima and maxima for each PIFA. Next, finite ground planes are altered using the gained insight to enlarge the bandwidth for an antenna with a fixed maximum ground plane size. The goal of this work is to use the developed bandwidth analysis technique to inform the synthesis of PIFAs that require broader bandwidths.

DIELECTRIC RESONATOR ANTENNA ARRAYS FOR MICROWAVE ENERGY HARVESTING AND FAR-FIELD WIRELESS POWER TRANSFER

This paper presents dielectric resonator antennas (DRAs) for efficient energy harvesting or wireless power transfer in the microwaves regime. A single DRA and 1 × 3 array were used to build foundation profiles for DRAs as energy absorbers. The proposed structures were designed and fabricated to resonate around 5.5 GHz. The study examined different factors that affect the absorbed power efficiency. The size of ground plane and coupling between dielectric resonator (DR) elements in an array were studied, highlighting their effects on the overall efficiency of the antenna structure for different incident polarizations. A 5 × 5 array was built based on the studied factors and tested numerically and experimentally. Measurements showed that energy absorption efficiency as high as 67% can be achieved using an array of DR antennas.

Multibroadband Slotted Bow-Tie Monopole Antenna

In this letter, a coplanar waveguide (CPW)-fed multiband bow-tie monopole antenna is proposed. This antenna can be easily designed to meet the requirement of multiple operating frequencies by using the proposed approach. Multiple bent monopoles, which correspond to different operating frequencies, are generated by etching slots of different lengths in a bow-tie patch. The length of each bent monopole is determined under the quarter wavelength resonance condition. Each frequency band can be easily satisfied for the broadband character because the bow-tie patch can be treated as a broadband impedance-matching structure. This study demonstrates a triple-band slotted bow-tie monopole antenna for WLAN/WiMAX/LTE applications with bands of 2.4–2.7 GHz, 3.4–3.7 GHz, and 5.2–5.8 GHz. The size of the proposed antenna fabricated on a 0.8 mm-thick FR4 substrate with a dielectric constant of 4.2 without considering the ground plane size is only $19.5 \times 9.0~\hbox{mm}^{2}$ . The good agreement between the simulation results and the measurement validates the proposed design approach.

Bandwidth Enhancement Technique of the Meandered Monopole Antenna

A small dual-band monopole antenna with coplanar waveguide (CPW) feeding structure is presented in this paper. The antenna is composed of a meandered monopole, an extended conductor tail, and an asymmetrical ground plane. Tuning geometrical structure of the ground plane excites an additional resonant frequency band and thus enhances the impedance bandwidth of the meandered monopole antenna. Unlike the conventional monopole antenna, the new resonant mode is excited by a slot trace of the CPW transmission line. The radiation performance of the slot mode is as similar as that of the monopole. The parametrical effect of the size of the one-side ground plane on impedance matching condition has been derived by the simulation. The measured impedance bandwidths, which are defined by the reflection coefficient of −6 dB, are 186 MHz (863–1049 MHz, 19.4%) at the lower resonant band and 1320 MHz (1490–2810 MHz, 61.3%) at the upper band. From the results of the reflection coefficients of the proposed monopole antenna, the operated bandwidths of the commercial wireless communication systems, such as GSM 900, DCS, IMT-2000, UMTS, WLAN, LTE 2300, and LTE 2500, are covered for uses.

RFID TAG ANTENNA FOR METALLIC OR NON-METALLIC SURFACES

A capacitively fed rectangular patch antenna for anti-metal RFID tag was studied. It was found that by using capacitively feeding and a thin micro-strip line, the input impedance could be stabilized with respect to ground plane size. As a result, the reading range degradation was avoided, and the presented antennas have almost the same reading range when used on metal or non-metal objects. The mechanism was explained by a basic antenna design and a transmission line model. Then a more practical compact design having much smaller size was presented. Prototypes of both the basic design and the compact design were fabricated and tested. The testing results validated the effectiveness of the designing method.

ENHANCED RADIATION PATTERNS OF A WIDE-BAND STRIP-FED DIELECTRIC RESONATOR ANTENNA

A simple wide-band rectangular dielectric resonator antenna (DRA) is designed for the X-band and Ku-band applications. The DRA is excited by a vertical strip placed on the middle of the DRA wide side wall through a coaxial probe attached to a finite size ground plane. Good agreement between measured and simulated results is obtained. The measured 10 dB return loss bandwidth of the antenna is about 7.8 GHz (63%). The simulated gain of the antenna is 6.1 dBi at 12 GHz. The antenna excites undesired modes that perturb the radiation patterns and increase the cross-polarization level. The dielectric resonator is wrapped by a conducting strip to suppress some modes and improve the radiation characteristics of the antenna. Adding the strip reduces the cross polarization level and improves the co-polarization radiation pattern.

A high gain broadband circular patch antenna with spiral‐shaped slot‐loaded modified ground plane

ABSTRACTA high gain broadband circular microstrip patch antenna with spiral shape slot‐loaded square ground plane is presented. The effects of introduction of spiral shaped slots of the square ground plane on different parameters of the antenna are studied. Maximum impedance bandwidth of 123% is obtained with modified square ground plane of size 60 × 60 mm. Highest gain achieved is 6 dBi. Simultaneously, the antenna also exhibits a compactness of 93%. The simulated results are confirmed experimentally. The proposed antenna is simple in structure and may be widely used in wireless communications. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2044–2046, 2014