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

Omnidirectional antenna with modified ground plane for wideband dvb in handheld devices

Miniaturized monopole planar antennas operating in the VHF/UHF band applied for Digital Video Broadcasting and mobile communication have gained research interest due to their low-profile, compact, and wideband nature. This antenna is capable of penetrating surfaces more easily, faster and can broadcast larger data because it operates in the wideband. The challenge of designing an antenna small enough to be adopted for Digital Video Broadcasting in handheld devices with capabilities of covering the DVB wideband and at the same time omnidirectional, with enough gain, good impedance coefficient which translates into efficiency is the drive of this paper. The proposed antenna in this paper is a rectangular patch with two large slots created in its radiating surface and extension on its edges for wider bandwidth and better matching. It employs a modified ground plane that uses coupling to achieve low return loss. CST microwave studio software was used for the simulation and optimization. The characteristics and simulated results are analyzed before the prototype structure is fabricated on an FR-4 substrate. A monopole planar antenna with total dimensions of 185 × 45 × 1.6 mm3 with an omnidirectional radiation pattern in the H-plane is fabricated and the results are presented. The antenna has high impedance bandwidth characteristics with operating frequency at -10 dB return loss from 470 MHz to 900 MHz and about 63% bandwidth efficiency. It has a VSWR ratio of less than 2. The significance of the various sections of the antenna together with the simulated and fabricated results is presented. It shows a suitable antenna with a wide operating frequency domain. The proposed antenna would be useful in Africa's development agenda in wide-area wireless communication as countries are migrating to DVB-T2 and DVB-NGH space

Mutual coupling suppression in multiple microstrip antennas for wireless applications

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonMutual Coupling (MC) is the exchange of energy between multiple antennas when placed on the same PCB, it being one of the critical parameters and a significant issue to be considered when designing MIMO antennas. It appears significantly where multiple antennas are placed very close to each other, with a high coupling affecting the performance of the array, in terms radiation patterns, the reflection coefficient, and influencing the input impedance. Moreover; it degrades the designed efficiency and gain since part of the power that could have been radiated becomes absorbed by other adjacent antennas’ elements. The coupling mechanism between multiple antenna elements is identified as being mainly through three different paths or channels: surface wave propagation, space (direct) radiation and reactive near-field coupling. In this thesis, various coupling reduction approaches that are commonly employed in the literature are categorised based on these mechanisms. Furthermore, a new comparative study involving four different array types (PIFA, patch, monopole, and slot), is explained in detail. This thesis primarily focuses on three interconnected research topics for mutual coupling reduction based on new isolation approaches for different wireless applications (i.e. Narrowband, Ultra-wide-band and Multi-band). First, a new Fractal based Electromagnetic Band Gap (FEBG) decoupling structure between PIFAs is proposed and investigated for a narrowband application. Excellent isolation of more than 27 dB (Z-X plane) and 40 dB (Z-Y plane) is obtained without much degradation of the radiation characteristics. It is found that the fractal structures can provide a band-stop effect, because of their self-similarity features for a particular frequency band. Second, new UWB-MIMO antennas are presented with high isolation characteristics. Wideband isolation (≥ 31 dB) is achieved through the entire UWB band (3.1-10.6 GHz) by etching a novel compact planar decoupling structure inserted between these multiple UWB antennas. Finally, new planar MIMO antennas are presented for multi-band (quad bands) applications. A significant isolation improvement over the reference (≥ 17 dB) is achieved in each band by etching a hybrid solution. All the designs reported in this thesis have been fabricated and measured, with the simulated and measured results agreeing well in most cases

Multiple Slot Fractal Structured Antenna for Wi-Fi and Radio Altimeter for uncertain Applications

A multiple slot fractal antenna design has been determined communication efficiency and its multi-function activities.  High-speed small communication devices have been required for future smart chip applications, so that researchers have been employed new and creative antenna design. Antennas are key part in communication systems, those are used to improve communication parameters like gain, efficiency, and bandwidth. Consistently, modern antennas design with high bandwidth and gain balancing is very difficult, therefore an adaptive antenna array chip design is required. In this research work a coaxial fed antenna with fractal geometry design has been implemented for Wi-Fi and Radio altimeter application. The fractal geometry has been taken with multiple numbers of slots in the radiating structure for uncertain applications. The coaxial feeding location has been selected based on the good impedance matching condition (50 Ohms). The overall dimension mentioned for antenna are approximately 50X50X1.6 mm on FR4 substrate and performance characteristic analysis is performed with change in substrate material presented in this work. Dual-band resonant frequency is being emitted by the antenna with resonance at 3.1 and 4.3 GHz for FR4 substrate material and change in the resonant bands is obtained with change in substrate. The proposed Antenna is prototyped on Anritsu VNA tool and presented the comparative analysis like VSWR 12%, reflection coefficient 9.4%,3D-Gain 6.2% and surface current 9.3% had been improved

A miniaturized triple-band and dual-polarized monopole antenna based on a CSRR perturbed ground plane

This paper proposes a new triple-band monopole antenna based on Complementary Split Ring Resonators (CSRR) perturbing the ground plane (GND). The antenna consists of an inverted-L-shaped monopole fed by a modified microstrip line with two CSRRs cut out of the ground plane. The operational bands are independently controlled by the CSRR unit cell parameters. In addition, the antenna presents a dual-polarization performance (vertical polarization at 2.4 GHz band and horizontal polarization at both 3.6 and 5.9 GHz bands). The designed antenna is fully planar and low profile avoiding the vias with the ground plane and covering the WLAN, WiMAX, and IEEE 801.11p bands at 2.45, 3.6, and 5.8 GHz. A compact prototype ( 0.32λ0×0.32λ0 being λ0 is the wavelength corresponding to the lowest resonance frequency) has been fabricated and measured showing good agreement between simulations and measurements. The measured impedance bandwidths are 10% (2.38-2.63 GHz), 2.5% (3.54-3.63 GHz), and 20% (5.83-7.12 GHz) whereas the measured gains are 1.34, 0.68, and 2.65 dBi at 2.4, 3.6, and 5.9 GHz respectively.This work was supported by PID2019-109984RB-C41

A compact CPW-fed printed UWB antennas

In this work, we present the design and analysis of compact coplanar waveguide-fed ultra wideband rectangular antennas. These proposed antennas exhibit very wide operating bandwidth (return loss ≤ -10dB) which covers 3.2-15 GHz range, which means a relative bandwidth of 126% covering FCC defined UWB band with stable omnidirectional radiation patterns and important gain. The parameters of antennas have been investigated and optimized by using two electromagnetic solvers. A good agreement has been obtained between simulation and measurement results. These antennas are useful for UWB indoor applications, handheld and wireless communication requiring low profile antennas. The antennas achieved are low cost and easy to fabricate and integrate with RF circuit. The simulated and the experimental results are described and discussed

UWB antennas for wireless communications

This thesis focuses on four inter-related research topics on the design and analysis of compact planar ultra wide-band (UWB) monopole antennas for future wireless communications, namely, a planar super-wide-band (SWB) monopole antenna, a planar UWB antenna with band-notched characteristics, a planar UWB antenna with reconfigurable band-rejection features, and a planar UWB multiple-input and multiple-output (MIMO) antenna. A novel Mickey-mouse shaped planar monopole antenna with SWB performance is proposed and investigated. Three different techniques for bandwidth enhancement are implemented. The antenna is evolved from the traditional circular monopole antenna and has achieved an impedance bandwidth of more than 100:1 and a stable radiation patterns over a wider bandwidth. The design of a compact planar UWB monopole antenna (22 mm × 34 mm), incorporated with five m-shaped resonators (MSRs) at different positions, to achieve quintuple-band-notched performance is presented. The frequency-domain performance (in term of reflection coefficients, realized gain, efficiency, and radiation pattern), and time-domain performance (in term of pulse responses and fidelity), are investigated by simulation and measurement. The results show that the proposed UWB antenna has approximately omnidirectional radiation patterns and excellent band-notched behaviours and good time domain performance with the fidelity of more than 85.5% in the pulse response. A planar UWB monopole antenna with reconfigurable band-notched characteristics is also introduced. The band rejection is realized by incorporating two co-directional split ring resonators (CSRR) on the radiator element. Switches are added to the CSRR structures to achieve the reconfigurability. The proposed antenna can operate at different switching states including a UWB state, single and dual band-notched states with good rejection behaviours. Good radiation patterns and gain values are also obtained for different switching states. This compact wideband antenna can be very good candidate for a wide range of mobile portable applications. A compact planar UWB-MIMO antenna (60 mm × 45 mm) is presented for wireless applications. The wideband isolation of more than 15 dB is achieved by etching a new trident-like slot on the ground plane of the antenna. An equivalent circuit have been introduced for analysis and the diversity performances are studied. The results show that the proposed MIMO antenna is a very good candidate for wireless applications. The study of these four special antennas has demonstrated that, using various techniques, the planar monopole antenna can be an excellent choice for a wide range of wireless communication applications

A Novel UWB Reconfigurable Filtering Antenna Design With Triple Band-Notched Characteristics By Using U-Shaped Coppers

This paper proposed an UWB antenna with triple reconfigurable notch filters. By presenting there U-shaped coppers in the design, the potential triple interference in UWB applications can be rejected. Six PIN diodes are putted on the coppers to represent the OFF and ON tunable status in order to add reconfigurable characteristics to the UWB antenna. By using this ON and OFF tunable method, the current distribution of the proposed design changes and enables the antenna to have eight operation modes. The results prove that the proposed design can operate over the entire UWB frequency range (3.1 GHz to 10.6 GHz) and can filter out the target signals from the WLAN upper band (5.725 to 5.825 GHz), WLAN lower band (5.15 to 5.35 GHz) and X band frequency system (7.9 to 8.4 GHz) in one of the tunable configuration

Design and Analysis of Planar Monopole Antennas for Ultra Wide Band Applications

This thesis presents the work on the design of single element and two element (MIMO) antennas. The proposed designs are analyzed for different performance parameters separately. First, a compact lotus shaped planar monopole antenna is proposed and extended by creating two slots for dual notch performance for narrow band applications. The presented antenna fabricated on a 44~38~1.58mm3 on thick FR4 substrate and covers the frequency range from 2.86 to 14.0 GHz and is fed by 50 Ħ Microstrip line. The extended work of proposed antenna covers the wide range 2.8 to 11 GHz with notch frequencies at 3.458 and 5.51GHz ranging from 3.35GHZ-3.566GHz and 5.285GHz-5.771GHz frequencies. Second, a two element compact UWB MIMO Antenna systems are designed on an FR4 substrate of dimensions 44~88mm2 of a thickness 1.6mm with lotus shaped elements and antennas are placed in three different angular positions on the substrate. A fork-shaped structure is introduced in the ground plane to increase the isolation between the antennas. Simulated results of S-parameters of the proposed antenna system are obtained and a high isolation of less than -15 dB is achieved throughout the band and it is quite suitable for MIMO applications. The extended work carried out on creating a dual notch for the different designs placed in three different positions for narrowband applications. The high isolation of less than -15 dB is achieved throughout the band and notch frequencies are situated at 3.44GHz and 5.375GHz by covering WiMAX and WLAN narrow band applications. Among three the antenna placed parallel on a substrate is fabricated and measured. The measured results are well matched to the simulated results

Recent Advances in Antenna Design for 5G Heterogeneous Networks

The aim of this book is to highlight up to date exploited technologies and approaches in terms of antenna designs and requirements. In this regard, this book targets a broad range of subjects, including the microstrip antenna and the dipole and printed monopole antenna. The varieties of antenna designs, along with several different approaches to improve their overall performance, have given this book a great value, in which makes this book is deemed as a good reference for practicing engineers and under/postgraduate students working in this field. The key technology trends in antenna design as part of the mobile communication evolution have mainly focused on multiband, wideband, and MIMO antennas, and all have been clearly presented, studied and implemented within this book. The forthcoming 5G systems consider a truly mobile multimedia platform that constitutes a converged networking arena that not only includes legacy heterogeneous mobile networks but advanced radio interfaces and the possibility to operate at mm wave frequencies to capitalize on the large swathes of available bandwidth. This provides the impetus for a new breed of antenna design that, in principle, should be multimode in nature, energy efficient, and, above all, able to operate at the mm wave band, placing new design drivers on the antenna design. Thus, this book proposes to investigate advanced 5G antennas for heterogeneous applications that can operate in the range of 5G spectrums and to meet the essential requirements of 5G systems such as low latency, large bandwidth, and high gains and efficiencies