Wideband and UWB antennas for wireless applications. A comprehensive review

A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account. The performances of small, low-profile, and dielectric resonator antennas are illustrated paying particular attention to the application areas concerning portable devices (mobile phones, tablets, glasses, laptops, wearable computers, etc.) and radio base stations. This information provides a guidance to the selection of the different antenna geometries in terms of bandwidth, gain, field polarization, time-domain response, dimensions, and materials useful for their realization and integration in modern communication systems

Ground defected planar super-wideband antenna: a suitable transceiver for short distance wireless communication

A planar microstrip patch super-wideband antenna is presented for short distance wireless communication applications. The antenna is comprised of a simple patch and a ground plane and etched on two sides of a 1.6 mm-thick standard FR4 substrate material with a relative permittivity of 4.5 and loss tangent (0.02). The proposed antenna possesses a compact size of 29 × 20.5 mm2 with an electrical dimension of 0.25 λ × 0.18 λ. To enhance the operating bandwidth, the ground plane is modified by adding seven small rectangular slots on its upper side. Through numerical studies, it is found that insertion of the slots enhances the coupling between the patch and ground plane resulting in achievement of a super-wide operating band. From the measurements, it is observed that the fabricated prototype antenna has a bandwidth from 2.63 to more than 18 GHz, a symmetric omnidirectional radiation characteristic and the maximum peak gain of 5.85 dBi which makes it a suitable transceiver for short distance communication applications

Microstrip Array Antenna using Series-Corporate Feed for Navigation System

In this paper, the proposed antenna consists of a single transmission line for 6-elements microstrip array antenna using Rogers RT5880 substrate material with a dielectric constant (εr) of 2.2 and thickness of 0.787 mm for navigation applications. The array structures of unequal patches placement are proposed with corporate feed line and H-shaped configurations are employed on the substrate and used the microstrip feed line with a corporate feed network excited via 50 Ω with T-junction method to control the feed for each group. 6-elements microstrip array antenna has operated at the resonant frequency of 1.27 GHz was obtained between the frequency from 1.2663 GHz to 1.2734 GHz where the S11-parameters of the structure designed and simulation below than <-10 dB. The analysis shows the antenna gain has increased 72.6% with high directivity as compared to single elements microstrip antenna. The radiation characteristics and other array parameters are evaluated with respect to the application requirements. However, circular polarization has obtained in 6-elements array antenna as the axial ratio is successfully achieved below than -3dB. The antenna efficiency, the current distribution, VSWR, and S11-parameters of the proposed 6-elements CP microstrip array antenna have been presented and discussed in detail. The design methodology and the measurement results have been presented and discussed in this paper

A Novel Transparent UWB Antenna for Photovoltaic Solar Panel Integration and RF Energy Harvesting

A novel transparent ultra-wideband antenna for photovoltaic solar-panel integration and RF energy harvesting is proposed in this paper. Since the approval by the Federal Communications Committee (FCC) in 2002, much research has been undertaken on UWB technology, especially for wireless communications. However, in the last decade, UWB has also been proposed as a power harvester. In this paper, a transparent cone-top-tapered slot antenna covering the frequency range from 2.2 to 12.1 GHz is designed and fabricated to provide UWB communications whilst integrated onto solar panels as well as harvest electromagnetic waves from free space and convert them into electrical energy. The antenna when sandwiched between an a-Si solar panel and glass is able to demonstrate a quasi omni-directional pattern that is characteristic of a UWB. The antenna when connected to a 2.55-GHz rectifier is able to produce 18-mV dc in free space and 4.4-mV dc on glass for an input power of 10 dBm at a distance of 5 cm. Although the antenna presented in this paper is a UWB antenna, only an operating range of 2.49 to 2.58 GHz for power scavenging is possible due to the limitation of the narrowband rectifier used for the study

Novel Pseudo Magneto-electric Dipole Antennas

One of the major requirements for modern wireless communications is very high data transmission, so antennas with simple geometry, wide operation bandwidth and stable high gain features are in increasing demand. In this thesis, three novel pseudo magneto-electric (ME) dipole antennas operating in 5G Frequency Range 1 (FR1) sub-6GHz and Frequency Range 2 (FR2) millimeter-wave (mmW) band are introduced and analyzed. Comparing with conventional ME dipole antennas, which always require a vertical quarter-wave cavity to generate the magnetic dipole resonance, the pseudo-ME dipole designs proposed in this thesis do not rely on the cavity to provide the complementary magnetic dipole mode, therefore, they have extremely simple geometry. Meanwhile, it achieved wide bandwidth (50.30%) and high gain (average 8.74 dBi) the in-band gain variation is only ± 1dB. Based on the novel cavity-less Pseudo-ME dipole antenna geometry, a wide axial ratio bandwidth (54.1%) circularly polarized pseudo-ME dipole antenna is also designed to overcome the polarization misalignment problem in multipath-rich wireless environments, this antenna has two pairs of orthogonal electric dipoles and magnetic dipoles to achieve the wide axial ratio bandwidth performance. Finally, an aperture-coupled printed pseudo-ME dipole antenna is designed for operating in millimeter-wave band, it has 32.3% of impedance bandwidth and stable high gain 7.4 ± 0.8 dBi. Especially, there is none typical via-hole formed cavity in the geometry, so the fabrication of the mmW band antenna becomes simpler

Compact circularly polarized truncated square ring slot antenna with suppressed higher resonances

This paper presents a compact circularly polarized (CP) antenna with an integrated higher order harmonic rejection filter. The proposed design operates within the ISM band of 2.32 GHz± 2.63 GHz and is suitable for example for wireless power transfer applications. Asymmetrical truncated edges on a square ring create a defected ground structure to excite the CP property, simultaneously realizing compactness. It offers a 50.5% reduced patch area compared to a conventional design. Novel stubs and slot shapes are integrated in the transmission line to reduce higher (up to the third) order harmonics. The proposed prototype yields a -10 dB reflection coefficient (S11) impedance bandwidth of 12.53%, a 3 dB axial ratio bandwidth of 3.27%, and a gain of 5.64 dBi. Measurements also show good agreement with simulations. © 2017 Sabran et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Antenna Array Designs For Directional Wireless Communicatoin

Ph.D. Thesis. University of Hawaiʻi at Mānoa 2018

Low-Profile Wideband Antenna Arrays for Mobile Satellite and 5G Communication

Three innovative low-profile antenna arrays are designed and tested for vehicular satellite and 5G communication. All of the systems presented target key challenges of GEO, LEO and 5G communication. Each design provides a high level of performance for the given application in a far more compact and lower cost design than existing systems.Firstly, a wideband curl antenna array is developed to enable L-band GEO satellite communication for emergency vehicles. This novel 1×3 rotated array utilises a hybrid switch beam and phase shifting technique to enable full beamforming down to 70° in all directions with 40% lower cost than standard phased array systems. Uniquely, this provides excellent azimuth beam steering at low angles from a linear array. This system also utilises a high impedance surface to reduce the height of the antenna elements by 50% compared to existing curl antenna designs.Secondly, a shared aperture antenna array is developed to enable Ka-band LEO satellite communication for vehicular integration. This system utilise a new combination of circular polarised triangular antennas in an interlaced planar triangular lattice such that the topology provides optimal tessellation. As a result, the system provides high performance beam steering and reconfigurable circular polarisation in a highly compact design. This array has been developed such that it is suitable for common PCB manufacturing methods. Unlike existing shared aperture arrays for LEO terminals, this topology enables reconfigurable circular polarisation in a single, planar PCB structure.Finally, a low-cost wideband compressed spiral antenna array is designed and fabricated for global 5G ground-to-air communication for aircraft. An innovative spiral antenna optimisation is presented where the spiral is highly compressed such that it can provide an axial beam over a wide bandwidth while maintaining a lower profile than existing wideband solutions

Wideband Dual Circularly Polarized Antenna for Intelligent Transport Systems

A wideband dual circularly polarized (DCP) antenna is presented for intelligent transport system (ITS) applications, which can be used to improve the receiver sensitivity and communication quality of ITS. The presented DCP antenna is composed of an orthogonal power divider (OPD) with two orthogonal input ports, four phase shifters for quadrature phase output, and four crossed dipoles for DCP radiation. Detailed equivalent circuit analysis shows that the OPD has two orthogonal inputs and four equal magnitude in-phase and out-of-phase outputs. To achieve two sets of orthogonal quadrature output signals for DCP radiation, the lumped element based differential right-hand transmission line unit cell and left-hand transmission line unit cell are elaborately introduced as the ±45° phase shifters, and incorporated into the OPD. Eventually, orthogonal quadrature signals are successfully obtained and fed to the crossed dipoles for DCP radiation. The proposed antenna was then designed, fabricated, and measured for ITS applications. The measured results show that the overlapped impedance bandwidth of both two input ports is 1.07–1.85 GHz (53.4%), and the isolation is higher than 15.2 dB. Moreover, low axial ratio (<1.7 dB) and symmetrical radiation patterns are achieved for unidirectional DCP radiation