37 research outputs found
Ultra Wideband
Ultra wideband (UWB) has advanced and merged as a technology, and many more people are aware of the potential for this exciting technology. The current UWB field is changing rapidly with new techniques and ideas where several issues are involved in developing the systems. Among UWB system design, the UWB RF transceiver and UWB antenna are the key components. Recently, a considerable amount of researches has been devoted to the development of the UWB RF transceiver and antenna for its enabling high data transmission rates and low power consumption. Our book attempts to present current and emerging trends in-research and development of UWB systems as well as future expectations
Radar Technology
In this book “Radar Technology”, the chapters are divided into four main topic areas: Topic area 1: “Radar Systems” consists of chapters which treat whole radar systems, environment and target functional chain. Topic area 2: “Radar Applications” shows various applications of radar systems, including meteorological radars, ground penetrating radars and glaciology. Topic area 3: “Radar Functional Chain and Signal Processing” describes several aspects of the radar signal processing. From parameter extraction, target detection over tracking and classification technologies. Topic area 4: “Radar Subsystems and Components” consists of design technology of radar subsystem components like antenna design or waveform design
Antennas and Propagation
This Special Issue gathers topics of utmost interest in the field of antennas and propagation, such as: new directions and challenges in antenna design and propagation; innovative antenna technologies for space applications; metamaterial, metasurface and other periodic structures; antennas for 5G; electromagnetic field measurements and remote sensing applications
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
Antenna Design for 5G and Beyond
With the rapid evolution of the wireless communications, fifth-generation (5G) communication has received much attention from both academia and industry, with many reported efforts and research outputs and significant improvements in different aspects, such as data rate speed and resolution, mobility, latency, etc. In some countries, the commercialization of 5G communication has already started as well as initial research of beyond technologies such as 6G.MIMO technology with multiple antennas is a promising technology to obtain the requirements of 5G/6G communications. It can significantly enhance the system capacity and resist multipath fading, and has become a hot spot in the field of wireless communications. This technology is a key component and probably the most established to truly reach the promised transfer data rates of future communication systems. In MIMO systems, multiple antennas are deployed at both the transmitter and receiver sides. The greater number of antennas can make the system more resistant to intentional jamming and interference. Massive MIMO with an especially high number of antennas can reduce energy consumption by targeting signals to individual users utilizing beamforming.Apart from sub-6 GHz frequency bands, 5G/6G devices are also expected to cover millimeter-wave (mmWave) and terahertz (THz) spectra. However, moving to higher bands will bring new challenges and will certainly require careful consideration of the antenna design for smart devices. Compact antennas arranged as conformal, planar, and linear arrays can be employed at different portions of base stations and user equipment to form phased arrays with high gain and directional radiation beams. The objective of this Special Issue is to cover all aspects of antenna designs used in existing or future wireless communication systems. The aim is to highlight recent advances, current trends, and possible future developments of 5G/6G antennas
Substrate Integrated Waveguide (SIW) and Superconducting Filters
Substrate integrated waveguides (SIW) provide an excellent compromise between size and loss reduction for applications in planar circuits. SIW filters provide a better Q-factor than microstrip filters and a significant reduction in size compared to waveguide filters. The use of multi-band filters has become increasingly more common because they provide the opportunity to reduce the total footprint in both RF transmitters and receivers. This thesis investigates the design process of a single-band quasi-elliptic and dual-band SIW filter. We use several methods to design the single-band SIW, and compare the simulated results of each. These filters are designed on 0.508mm thick Rogers4003C substrate, fabricated, and measured. The introduction of negative cross-coupling in SIW structures is achieved by using etched coplanar waveguide (CPW) lines. This negative cross-coupling allows for the introduction of transmission zeros in both designed filters. We carefully investigate the transition technology to ensure that we achieve a wideband match between microstrip and SIW. The thickness of the substrate provides some challenges in the matching, so we take extra consideration to overcome this. The second part of this thesis explores the design of lumped element superconducting bandpass filters. When designing filters in the kHz and MHz range, several challenges arise. The first is the ability to use certain software: Sonnet and HFSS both have a limited ability to simulate low-frequency components. More specifically, Sonnet demonstrates an inability to accurately simulate inductors, while simulation times in HFSS are prohibitively long. Momentum thus proves to be the best EM simulator for this task. The second challenge is the need to miniaturize these filters. At such low frequencies, the filter’s footprint is quite large, therefore the reduction in size is extremely important. We implement traditional methods, such as stacked spiral inductors and vertically integrated capacitors, and achieve further size reduction by modifying the circuit topology to reduce the components with the largest footprints. We also introduce transmission zeros to improve the upper and lower band rejection. We then design a three-pole classical Chebyshev filter and a three-pole quasi-elliptic filter that uses a miniaturized circuit topology. Finally, we design a 10% six-pole superconducting slotline resonator filter. Slotline resonators provide an excellent quality factor, even at higher frequencies. A CPW-to-slotline transition is implemented so that the device can be measured using a ground-signal-ground probe. The resonators implemented use dual-spiral inductors and interdigital capacitors. This allows for flexibility when choosing the resonant frequency. All superconducting filters are fabricated using the MIT-Lincoln Lab (MIT-LL) multilayer niobium fabrication process
Reconfigurable Antennas
In this new book, we present a collection of the advanced developments in reconfigurable antennas and metasurfaces. It begins with a review of reconfigurability technologies, and proceeds to the presentation of a series of reconfigurable antennas, UWB MIMO antennas and reconfigurable arrays. Then, reconfigurable metasurfaces are introduced and the latest advances are presented and discussed
Potentiel de la technologie MID pour les composants passifs et des antennes
MID (Molded Interconnect Devices) technology, owing to their electrical performance,flexibility in RF circuits, its potential to reduce the number of components, process steps andminiaturization of the final product, has led to some new constraints to the RF (RadioFrequency) and microwave domain. Molded components are interconnected withthermoplastic substrates and conductive traces are injected on the surface. The objective ofthis thesis is to study the compatibility of MIDs for RF applications. The advantages of MIDtechnology in the RF domain is exploited for transmission lines, passive filters, directionalcouplers and planar and 3D antennas realization. The RF characterization of various MIDsubstrate materials and the study of the performance of the above RF components based onvarious MID fabrication technologies are included in the thesis. Finally, an permittivityimprovement study of some thermoplastics are also studied.La technologie MID (Molded Interconnect Device), fait de leur performance électrique, la flexibilitédans les circuits RF, le potentiel de réduire le nombre de composants, les étapes du processus et laminiaturisation du produit final, a conduit à de nouvelles contraintes à la RF (Radio Frequency) et ledomaine des micro-ondes. Composants moulés sont interconnectées avec des substratsthermoplastiques et les pistes conductrices sont injectés sur la surface. L'objectif de cette thèse estd'étudier la compatibilité de MID pour les applications RF. Les avantages de la technologie MID dansle domaine RF est exploitée pour les lignes de transmission, filtres passifs, coupleurs directionnels etantennes réalisation. La caractérisation RF de différents matériaux de substrat MID et l'étude de laperformance des composants RF ci-dessus sur la base de différentes technologies de fabrication MIDsont inclus dans la thèse. Enfin, le concept d'une étude d'amélioration de la permittivité de certainsthermoplastiques sont également étudiés