Design of Compact Monopole Antenna using Double U-DMS Resonators for WLAN, LTE, and WiMAX Applications

This paper is under in-depth investigation due to suspicion of possible plagiarism on a high similarity indexIn this research, a novel wide-band microstrip antenna for wideband applications is proposed. The proposed antenna consists of a square radiating patch and a partial ground plane with a smal rectangular notch-shape. Two symmetrical U-slots are etched in radiating patch. The defected microstrip U-shapes and the small notch improve the antenna characterestics such impedance wideband and the gain along the transmission area. The proposed antenna is simulated on an FR4 substrate of a dielectric constant of 4.3, thickness 1.6 mm, permittivity 4.4, and loss tangent 0.018. The simulation and optimization results are carried out using CST software.The antenna topology occupies an area of 30 × 40 × 0.8 mm3 or about 0.629λg × 0.839λg × 0.017λg at 3 GHz (the centerresonance frequency). The antenna covers the range of 2.1711 to 4.0531 GHz, which meet the requirements of the wireless local area network (WLAN), worldwide interoperability for microwave access (WiMAX) and LTE (Long Term Evolution) band applications. Good VSWR, return loss and radiation pattern characteristics are obtained in the frequency band of interest. The obtained Simulation results for this antenna depict that it exhibits good radiation behavior within the transmission frequency range

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

A Multi-Bandwidth Reconfigurable Patch Antenna for Devices in WLAN and UWB Technology Applications

This article introduces a process to design, simulate, and measure a novel multi-band patch antenna with different operation modes, i.e., band centers and bandwidths. Switching between operation modes is possible using a pair of PIN diodes to connect different parts of the antenna with the main antenna patch. Such a reconfigurable design allows for individual control of each frequency range. The main operation mode of the resulting antenna has an impedance bandwidth with two bands, one from 2.4 GHz to 2.73 GHz and another from 3.4 GHz to 5.73 GHz, with a maximum gain of 4.85 dBi and stable radiation patterns. The resulting antenna is suitable for applications using both ultra-wideband technologies and wireless local-area network (WLAN) technologiesProject eSAFE-UAV PID2019-106120RB-C32 funded by MCIN/AEI/10.13039/501100011033European Union’s Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement no. 955816SCHLUMBERGER FOUNDATION awar

Passive Planar Microwave Devices

The aim of this book is to highlight some recent advances in microwave planar devices. The development of planar technologies still generates great interest because of their many applications in fields as diverse as wireless communications, medical instrumentation, remote sensing, etc. In this book, particular interest has been focused on an electronically controllable phase shifter, wireless sensing, a multiband textile antenna, a MIMO antenna in microstrip technology, a miniaturized spoof plasmonic antipodal Vivaldi antenna, a dual-band balanced bandpass filter, glide-symmetric structures, a transparent multiband antenna for vehicle communications, a multilayer bandpass filter with high selectivity, microwave planar cutoff probes, and a wideband transition from microstrip to ridge empty substrate integrated waveguide

Reconfigurable Antennas and their Applications

One of the biggest challenge in modern communication systems is to provide a single antenna for different applications. Existing antenna systems are limited to some applications. So it is important to design a single reconfigurable antenna for multiple applications. Five different reconfigurable printed antennas for different applications are designed during the study of this thesis. In the first design an antenna for frequency reconfigurable applications is designed. The electrical length of the conductor is changed using PIN diodes and the resonance of antenna is shifted from 4.27 GHz to 3.56 GHz. Good agreement between simulated and measured results is observed. In the second and third designs, Ultra wideband (UWB) Multiple-Input Multiple-Output (MIMO) antennas with on-demand Wireless Local Area Network (WLAN) rejection are designed. The second design consists of two elements UWB-MIMO antenna and stubs are connected to the ground plane using PIN diodes. These stubs act as a stop-band filter and reject the band at 5.5 GHz center frequency. This design has a compact size of 23 x 39.8 mm2. The third design has almost same features as of second design but it has four elements. These elements are placed orthogonally to each other. The total size of this proposed design is 50 x 39.8 mm2. The ground plane is common and a band-stop design is placed between the ground planes. This band-stop design is connected with the ground plane using PIN diodes. When diodes are biased, the current is travelled to the nearly placed band-stop design and a notch is obtained around 5.5 GHz. In fourth design a reconfigurable array with a sensing circuit is designed. The array consists of four individual reconfigurable patches which are attached to the different conformal surfaces. These patches are reconfigured from 3.15 GHz to 2.43 GHz using PIN diodes. The correct phase at each element is provided using phase shifters. The sensing circuit is designed in such a way that only input voltage is changed to provide the correct phase on the switching frequency. The patterns of the array are recovered on both switching frequencies when array is attached to wedge or cylindrical surface. In the last design a series-fed array is designed. Composite Right/Left Handed Transmission Line (CRLH-TLs) are used instead of traditional meanderline microstrip lines to connect the array elements. These CRLH-TLs provided the zero phase at each connecting element, which resulted in broad side radiation patterns. To reconfigure the antenna to another frequency a small patch and second CRLH-TL is connected between array element

A Survey on Reconfigurable Microstrip Filter–Antenna Integration: Recent Developments and Challenges

Reconfigurable and tunable radio frequency (RF) and microwave (MW) components have become exciting topics for many researchers and design engineers in recent years. Reconfigurable microstrip filter–antenna combinations have been studied in the literature to handle multifunctional tasks for wireless communication systems. Using such devices can reduce the need for many RF components and minimize the cost of the whole wireless system, since the changes in the performance of these applications are achieved using electronic tuning techniques. However, with the rapid development of current fourth-generation (4G) and fifth-generation (5G) applications, compact and reconfigurable structures with a wide tuning range are in high demand. However, meeting these requirements comes with some challenges, namely the increased design complexity and system size. Accordingly, this paper aims to discuss these challenges and review the recent developments in the design techniques used for reconfigurable filters and antennas, as well as their integration. Various designs for different applications are studied and investigated in terms of their geometrical structures and operational performance. This paper begins with an introduction to microstrip filters, antennas, and filtering antennas (filtennas). Then, performance comparisons between the key and essential structures for these aspects are presented and discussed. Furthermore, a comparison between several RF reconfiguration techniques, current challenges, and future developments is presented and discussed in this review. Among several reconfigurable structures, the most efficient designs with the best attractive features are addressed and highlighted in this paper to improve the performance of RF and MW front end systems

Metamaterial antennas for cognitive radio applications

Cognitive radio is one of the most promising techniques to efficiently utilize the radio frequency (RF) spectrum. As the Digital Video Broadcasting-Handheld (DVB-H) band is targeted (470-862 MHz), the size of the antenna becomes challenging. Metamaterial concept is used as a miniaturization technique. Two antennas are designed, fabricated and measured. The first one achieved multiband operation by loading it with a metamaterial unit cell. These bands are controlled by engineering the dispersion relation of the unit cell. The second one, which is a 2-lumped elements loaded antenna, achieved wideband operation through the entire DVB-H band with a planar size of 5×2 cm^2. A model is proposed to explain, through simple numerical simulations and an optimization algorithm, the behavior of these component loaded antennas (which are equivalent to metamaterial inspired electrically small antennas)

Artificial Magnetic Conductor Integrated Textile Monopole Antenna

Wearable antenna is a fast growing field in application-oriented research, which introduced a new generation of garments capable of monitoring wear health, as well as environmental states. This thesis is concerned with the design and fabrication of a compact textile wearable antenna at operating frequency within the Industrial, Scientific and Medical (ISM) band, intended for integration into a flight jacket of the astronaut inside the habitat. The antenna is integrated with artificial material known as High Impedance Surface (HIS) for performance enhancement. The purpose of the system is to constantly monitor vital signals of the astronauts. The entire design cycle of wearable Co-Planar Waveguide (CPW) fed monopole antenna, starting from simulation-based design to fabricated prototype and antenna testing under different conditions was carried out in this thesis. Because of the lossy nature of human body tissues, the radiation efficiency of the antenna will be reduced due to the absorption of the radiated energy. Hence, changes in the radiation characteristics of the wearable antenna like operating frequency, gain and impedance bandwidth will take place. To overcome these challenges, HIS has been suggested and integrated with the monopole antenna to isolate the antenna from the ambient environments. This wearable antenna was tested under real operating conditions such as bending and crumpling conditions. Moreover, as the antenna operates near human body tissues, Specific Absorption Rate (SAR) assessment is required to consider the safety concerns of the antenna system. SAR analysis based on simulation results has been carried out in this thesis to show a significant reduction in SAR with the usage of HIS in the antenna system

Investigations on some compact wideband fractal antennas

Today’s small handheld and other portable devices challenge antenna designers for ultrathin, and high performances that have the ability to meet multi standards. In the context, fractal geometries have significant role for antenna applications with varying degree of success in improving antenna characteristics. In this thesis, we have investigated several wideband fractal monopole antennas. This work starts with design and implementation of Koch fractal, hybrid fractal, sectoral fractal, semi-circle fractal monopole antennas with discussion, covering their operations, electrical behavior and performances. The performances of these designs have been studied using standard simulation tools used in industry/academia and are experimentally verified. Frequency reconfigurable Koch snowflake fractal monopole antenna is also introduced. The present antenna can be used as an array element and has a wideband frequency of operation. A square Sierpinski monopole antenna has been designed, which is suitable for use in indoor UWB radio system and outdoor base station communication systems. Technique for obtaining a band stop function in the 5-6 GHz frequency band is numerically and experimentally presented. In addition to examining the performance of UWB system, the transfer function and waveform distortion are discussed. Finally, fractal antenna for array with MIMO environment is developed for mobile communication devices. Aim of this work is to achieve the acceptable performances in terms of isolation, envelope correlation coefficient, capacity loss, radiation patterns and efficiency. Furthermore, a wideband feed network prototype based on a modified Wilkinson power divider is designed. The designed feed network has been used in constructing 2-element and 4-element linear antenna arrays for high gain. This research work has addressed the effectiveness of fractal geometries in antenna and to bring-out the true advantages of their in antenna engineering