Download or read book Applications of Frequency Selective Surfaces in Polarization Control of Antennas written by Farhad Khosravi and published by . This book was released on 2014 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this dissertation is to address the problems associated with the current antennas deployed for wireless and navigation purposes. The focus in this work is on the circular polarization radiation of the antennas and the goal is to improve their radiation properties. The methods presented are based on Frequency Selective Surfaces (FSS); a group of periodic structures that behave as a spatial filter in principal but can be adjusted for other alterations to the incident electromagnetic wave. The FSS can be designed adequately so that the transmitted wave undergos a change in amplitude or phase. Moreover, adding the feature of selectivity over the incident polarization (TE or TM), can make the FSS shape the radiation pattern of the antenna in terms of amplitude or polarization; depending on whether the change is in the amplitude or phase of the wave transmitted through the FSS. The introduction chapter discusses the contemporary problems with these antennas and solution already proposed for these issues. Besides, it discusses drawbacks in current solutions and their limitations in those methods. The next chapter talks about bidirectional same sense circularly polarized antennas. The effort in this chapter is to present a method, besides those currently presented in literature, to achieve bidirectional antennas which radiate same sense of polarization on the two beams. A multilayer FSS is proposed to change the sense of the polarization by changing the phase of the wave passing through the structure. Then the FSS is combined with the antenna. Axial ratio of better than 3dB is achieved on both sides at the GPS L1 frequency band (f=1.575GHz). The next chapter is on improving one of the major issues in GPS antennas. Contemporary GPS antennas suffer from high axial ratio at angles close to 90o from the broadside direction. While there are some antennas available currently, they are either bulky or large in profile. It will be shown that, besides the presumed source of problem in previous works, another intrinsic factor in the radiation equations is also predominantly playing role in the corruption of axial ratio at those angles. Again, the approach presented for the aforementioned problem is based on FSS structures. The FSS will be appropriately designed for different angles to change the amplitude of the transmitted wave through the FSS and then is placed on the antenna. As will be shown, axial ratio is improved to the desired value with the low profile and low cost structure. As the results of this chapter shows, axial ratio of better than 2dB is achieved at angles up to 100o in all of the planes of the radiation pattern. Although the approach is to address one of the problems in the GPS antennas, the methodology seems pretty promising in many other applications where the radiation pattern of the antenna needs to be altered for different angles.

Download or read book Application of Frequency Selective Surfaces in Circular Polarization Antenna Technologies written by Robert Mervyn Orr and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Active Frequency Selective Surfaces for Antenna Applications Electronically to Control Phase Distribution and Reflective Transmissive Amplification written by and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A planar dipole grid antenna is described deposited on an active frequency selective (FSS) or polarization sensitive surface (PSS) electronically tuneable to control the spatial phase distribution and reflective/transmissive amplification. Such dipole grids can be used, for example, in reflector antenna systems composed of multiple reflective and/or transmissive subsystems to achieve and serve highly cost-effective multi-purpose applications. It is discussed how the resonant frequency or/and the type of polarization can be tuned just by varying the steering voltage or current of electronically tunable components such as varactor diodes or YIG films, respectively, implemented and integrated with each of the radiating dipole elements. The theoretical analysis for this paper is based upon a specific Floquet theory approach for single/double/triple periodic antenna structures. The resulting system of coupled vector integral equations for the unknown electric and magnetic current distribution is numerically solved by applying the method of moments supported by Galerkin s process of weighting. The experimental investigations were performed by developing a waveguide simulation technique in the frequency range of 7 to 16 GHz. Results of selected measurements are presented for quantities such as: the spatially dependent reflection/transmission coefficients (magnitude, phase) as a function of signal frequency; the intrinsic input impedance / matching of the various dipole elements involved, etc.; and in addition to that - the resulting electronically achievable phase advance/delay and amplification of the active antenna system as well. A one/two-dimensional enlarged planar dipole grid of about 40 mm x 25 mm in aperture size was deposited inside an adequately tapered waveguide to reduce tolerance problems and to suppress higher order modes.

Download or read book Handbook of Metamaterial Derived Frequency Selective Surfaces written by Shiv Narayan and published by Springer Nature. This book was released on 2023-01-02 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume provides a consolidated reference for the applications of frequency selective surfaces (FSS) technology in different sectors such as wireless communications, smart buildings, microwave and medical industries. It covers all aspects of metamaterial FSS technology starting from theoretical simulation, fabrication and measurement all the way to actual hardware implementation. Also included are in-depth discussions on the design methodologies of metamaterial FSS structures and their practical implementation in devices and components. It will be of interest to researchers and engineers working on developing metamaterial-FSS technology.

Download or read book Wireless Communications Networking and Applications written by Qing-An Zeng and published by Springer. This book was released on 2015-10-28 with total page 1265 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is based on a series of conferences on Wireless Communications, Networking and Applications that have been held on December 27-28, 2014 in Shenzhen, China. The meetings themselves were a response to technological developments in the areas of wireless communications, networking and applications and facilitate researchers, engineers and students to share the latest research results and the advanced research methods of the field. The broad variety of disciplines involved in this research and the differences in approaching the basic problems are probably typical of a developing field of interdisciplinary research. However, some main areas of research and development in the emerging areas of wireless communication technology can now be identified. The contributions to this book are mainly selected from the papers of the conference on wireless communications, networking and applications and reflect the main areas of interest: Section 1 - Emerging Topics in Wireless and Mobile Computing and Communications; Section 2 - Internet of Things and Long Term Evolution Engineering; Section 3 - Resource Allocation and Interference Management; Section 4 - Communication Architecture, Algorithms, Modeling and Evaluation; Section 5 - Security, Privacy, and Trust; and Section 6 - Routing, Position Management and Network Topologies.

Download or read book Frequency Selective Surface and Grid Array written by T. K. Wu and published by Wiley-Interscience. This book was released on 1995-07-31 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new addition to the prestigious Wiley Series in Microwave and Optical Engineering presents the first comprehensive coverage of Frequency Selective Surfaces (FSS) and active grid arrays, the two-dimensional periodically arranged array elements which may be etched on, or imbedded in, one or multiple layers of dielectric laminates. Because of its filtering frequency properties, this technology, which has attracted much interest over the past two decades, is being used to create filtering devices in microwave and higher frequency bands. With Frequency Selective Surface and Grid Array, it is no longer necessary to sift through a multitude of research papers and reports. Here, in one self-contained volume, is a thorough and up-to-date treatment of the concept, theory, applications, design, and fabrication techniques for periodic arrays. Furthermore, the book provides a complete reference for the technological advances in FSS, including the recent technology of active grid arrays. The first part of the book is devoted to the fundamentals and analytical techniques pertaining to FSS and grid arrays, including the advanced analyses of the conjugate gradient method and the generalized mode-matching technique with multiple dielectrics or nonsimilar grid arrays. In the second part, the book deals with implementation and application, describing the numerous applications of this technology, from the reflector antenna system used in satellite and spacecraft communications and bandpass radome to solar energy grids. The expert contributions to this volume make it useful both as a tutorial and as a reference for project and system/design engineers working with antennas, optics, millimeter waves, microwaves, radar, and low observable radomes. A comprehensive and self-contained reference for FSS and grid array technology Frequency Selective Surfaces (FSS), the two-dimensional periodic array elements with frequency filtering properties, have made important advances over the past two decades. They provide filtering devices in microwave and higher frequency bands with applications ranging from bandpass radome to solar energy grids—including satellite and spacecraft communications. Written by experts in the field and edited by Dr. T. K. Wu, an internationally recognized researcher in electromagnetics, Frequency Selective Surface and Grid Array provides the first comprehensive look at the theory, measurements, manufacturing, and applications of FSS and grid array technology. This publication brings together a wealth of information previously not available in book form, as well as material that has not been published anywhere, including: Passive and active grid design concepts and analysis, as well as FSS materials and fabrication techniques Practical design of frequency selective surface, high-performance bandpass radome, and active grid array Detailed equations for the reaction integrals Three computer codes to get readers started in the design of FSS and grid array (disk included) Case studies of FSS applications to multiband communication antenna systems Tables, figures, references, and numerous examples of practical FSS and grid array designs A tutorial analysis that includes the multilayer grid and dielectrics Frequency Selective Surface and Grid Array is an invaluable planning and design resource for research engineers and scientists dealing with FSS and grid array, as well as a handy reference for students and professionals entering the field.

Download or read book Printed Antennas written by Binod Kumar Kanaujia and published by CRC Press. This book was released on 2020-11-22 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Printed antennas have become an integral part of next-generation wireless communications and have been found to be commonly used to improve system capacity, data rate, reliability, etc. This book covers theory, design techniques, and the chronological regression of the printed antennas for various applications. This book will provide readers with the basic conceptual knowledge about antennas along with advanced techniques for antenna design. It covers a variety of analytical techniques and their CAD applications and discusses new applications of printed antenna technology such as sensing. The authors also present special reconfigurable antennas such as ME dipole, polarization, feeding, and DGS. The book will be useful to students as an introduction to design and applications of antennas. Additionally, experienced researchers in this field will find this book a ready reference and benefit from the techniques of research in printed antennas included in this book. Following are some of the salient features of this book: Covers a variety of analytical techniques and their CAD applications Discusses new applications of printed antenna technology such as sensing Examines the state of design techniques of printed antenna Presents special reconfigurable antennas such as ME dipole, polarization, feeding, and DGS

Download or read book Surface Electromagnetics written by Fan Yang and published by Cambridge University Press. This book was released on 2019-06-20 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides systematic coverage of the theory, physics, functional designs, and engineering applications of advanced electromagnetic surfaces.

Download or read book Frequency Selective Surfaces written by Ben A. Munk and published by John Wiley & Sons. This book was released on 2005-03-11 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: "...Ben has been the world-wide guru of this technology, providing support to applications of all types. His genius lies in handling the extremely complex mathematics, while at the same time seeing the practical matters involved in applying the results. As this book clearly shows, Ben is able to relate to novices interested in using frequency selective surfaces and to explain technical details in an understandable way, liberally spiced with his special brand of humor... Ben Munk has written a book that represents the epitome of practical understanding of Frequency Selective Surfaces. He deserves all honors that might befall him for this achievement." -William F. Bahret. Mr. W. Bahret was with the United States Air Force but is now retired. From the early 50s he sponsored numerous projects concerning Radar Cross Section of airborne platforms in particular antennas and absorbers. Under his leadership grew many of the concepts used extensively today, as for example the metallic radome. In fact, he is by many considered to be the father of stealth technology. "This book compiles under one cover most of Munk's research over the past three decades. It is woven with the physical insight that he has gained and further developed as his career has grown. Ben uses mathematics to whatever extent is needed, and only as needed. This material is written so that it should be useful to engineers with a background in electromagnetics. I strongly recommend this book to any engineer with any interest in phased arrays and/or frequency selective surfaces. The physical insight that may be gained from this book will enhance their ability to treat additional array problems of their own." -Leon Peters, Jr. Professor Leon Peters, Jr., was a professor at the Ohio State University but is now retired. From the early sixties he worked on, among many other things, RCS problems involving antennas and absorbers. This book presents the complete derivation of the Periodic Method of Moments, which enables the reader to calculate quickly and efficiently the transmission and reflection properties of multi-layered Frequency Selective Surfaces comprised of either wire and/or slot elements of arbitrary shape and located in a stratified medium. However, it also gives the reader the tools to analyze multi-layered FSS's leading to specific designs of the very important Hybrid Radome, which is characterized by constant band width with angle of incidence and polarization. Further, it investigates in great detail bandstop filters with large as well as narrow bandwidth (dichroic surfaces). It also discusses for the first time, lossy elements used in producing Circuit Analog absorbers. Finally, the last chapter deals with power breakdown of FSS's when exposed to pulsed signals with high peak power. The approach followed by most other presentations simply consists of expanding the fields around the FSS, matching the boundary conditions and writing a computer program. While this enables the user to obtain calculated results, it gives very little physical insight and no help in how to design actual multi-layered FSS's. In contrast, the approach used in this title analyzes all curves of desired shapes. In particular, it discusses in great detail how to produce radomes made of FSS's located in a stratified medium (Hybrid Radomes), with constant band width for all angles of incidence and polarizations. Numerous examples are given of great practical interest. More specifically, Chapter 7 deals with the theory and design of bandpass radomes with constant bandwidth and flat tops. Examples are given for mono-, bi- and tri-planar designs. Chapter 8 deals with bandstop filters with broad as well as narrow bandwidth. Chapter 9 deals with multi-layered FSS of lossy elements, namely the so-called Circuit Analog Absorbers, designed to yield outstanding absorption with more than a decade of bandwidth. Features material previously labeled as classified by the United States Air Force.

Download or read book Surface Electromagnetics written by Fan Yang and published by Cambridge University Press. This book was released on 2019-06-20 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by the leading experts in the field, this text provides systematic coverage of the theory, physics, functional designs, and engineering applications of advanced engineered electromagnetic surfaces. All the essential topics are included, from the fundamental theorems of surface electromagnetics, to analytical models, general sheet transmission conditions (GSTC), metasurface synthesis, and quasi-periodic analysis. A plethora of examples throughout illustrate the practical applications of surface electromagnetics, including gap waveguides, modulated metasurface antennas, transmit arrays, microwave imaging, cloaking, and orbital angular momentum (OAM ) beam generation, allowing readers to develop their own surface electromagnetics-based devices and systems. Enabling a fully comprehensive understanding of surface electromagnetics, this is an invaluable text for researchers, practising engineers and students working in electromagnetics antennas, metasurfaces and optics.

Download or read book ANTENNAS AND WAVE PROPAGATION written by YADAVA, R. L. and published by PHI Learning Pvt. Ltd.. This book was released on 2022-03-24 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This book, now in its Second Edition, is primarily intended for the undergraduate and postgraduate students of electronics and communication, electronics and electrical and telecommunication engineering. It provides a thorough understanding of the fundamentals and applications of the subject. The edition discusses the properties of several types of antennas such as dipoles, loop, Yagi-Uda, log-periodic, slot/DRA and microstrip antennas and also explains the phenomenon of wave propagation with emphasis on theory of operation and design procedures. It provides a comprehension of the principles of radiation and methods of excitation. The book also focuses on antenna measurements along with necessary requirements and different methods of measurement. Written in an easy-to-understand manner, the text includes several illustrative examples. A large number of solved examples and exercise problems with varying difficulty levels are included to reinforce the theoretical understanding of concepts. The book also contains several objective-type questions in each chapter along with a Question Bank at the end of the book. The Appendices provide a rich source of information and expressions as well as design data. NEW TO THE SECOND EDITION Separate new chapters are devoted to: • Reflector Antennas • Slot and Dielectric Resonator Antennas • Modern Antennas • Effect of Ground on Antenna Performances

Download or read book Proceedings of the 5th International Conference on Electrical Engineering and Control Applications Volume 2 written by Salim Ziani and published by Springer Nature. This book was released on with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metamaterial Technology and Intelligent Metasurfaces for Wireless Communication Systems written by Mehta, Shilpa and published by IGI Global. This book was released on 2023-08-18 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metamaterials and metasurfaces are enabling modern 5G/6G wireless systems to achieve high performance while maintaining efficient costs and sizes. In the wireless industry, transmission lines play a fundamental role in the development of guided wave elements, antennas, radio frequency identification (RFID) tags, and sensors whose efficiency may be enhanced using metamaterials. Additionally, a metamaterial absorber can solve the bandwidth issue of the internet of things (IoTs) backhaul network. Metasurfaces are also potential candidates for implementing reconfigurable intelligent surfaces (RISs) due to their special wireless communication capabilities. Metamaterial Technology and Intelligent Metasurfaces for Wireless Communication Systems compiles and promotes metamaterials research and sheds light on how metamaterials and metasurfaces will be used in the 5G era and beyond. Covering topics such as active and passive metamaterials, metasurfaces-inspired antennas, and metamaterials for RFID and sensors, this book is ideal for researchers, students, academicians, and professionals.

Download or read book Electromagnetic Wave Control Techniques of Metasurfaces and Metamaterials written by Wen, Jingda and published by IGI Global. This book was released on 2024-07-23 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the ever-evolving landscape of electromagnetic wave control, researchers face the pressing challenge of keeping pace with the rapid advancements in metasurface and metamaterial methods. As these technologies become increasingly integral to various engineering applications, educators and researchers seek a comprehensive resource that outlines the current state of the field and offers insights into its future prospects. Electromagnetic Wave Control Techniques of Metasurfaces and Metamaterials emerges as a timely solution, providing a detailed overview and a forward-looking perspective on wave control research using metasurfaces and metamaterials. With a firm focus on bridging the gap between theory and application, this book meets the critical need for a comprehensive understanding of key topics such as frequency selective surfaces, metasurface and metamaterial absorbers, reflectors, and the integration of deep learning and machine learning in these domains. This book equips readers with the knowledge and tools necessary to tackle real-world challenges in wavefront control, beam steering, and phase control by delving into the intricacies of broadband metasurfaces, metamaterials, and the underlying physics. Furthermore, it explores the unique capabilities of chiral metasurfaces and metamaterials, illuminating their diverse engineering applications and empowering the readers with practical insights.

Download or read book Design of The Compact Frequency Reconfigurable Multiband Antennas Using Rigid And Flexible Substrates For Wireless Portable Systems written by Dr. Koduri Sreelakshmi and published by Book Rivers. This book was released on 2023-09-17 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasmonic Metamaterials and Electromagnetic Devices written by Zhen Liao and published by Frontiers Media SA. This book was released on 2022-08-25 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technologies for Spacecraft Antenna Engineering Design written by Rui You and published by Springer Nature. This book was released on 2020-09-14 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on engineering design approaches for spacecraft antennas. Based on their functions in spacecraft, it discusses practical antenna design, measurement and testing. Most of the antennas covered originated at the China Academy of Space Technology (CAST), which has launched almost 300 satellites into orbit. The book presents antenna systems for seven existing spacecraft designs, while also introducing readers to new antenna technologies for spacecraft. This book is intended for researchers, graduate students, and engineers in various fields of aerospace technology and astronautics, especially spacecraft design, communication engineering and related areas.