Download or read book Radiation from Dielectric Loaded Waveguide Fed Aperture Antennas written by Martin D. Bradshaw and published by . This book was released on 1971 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical and experimental studies of the radiation pattern and input admittance of dielectric loaded waveguide fed aperture antennas are presented. The model consists of a waveguide fed, dielectric loaded aperture whose outer surface is flush with an infinite, perfectly conducting ground plane. The aperture and ground plane are covered by a dielectric layer. The window and the covering layer may be inhomogeneous in the direction of propagation. The analysis makes use of a mode-matching process that permits the effects of higher order modes to be taken into account in the dielectric loaded aperture section and in the covering layer. The window and layer are represented by an arbitrary number of inhomogeneous, lossy, dielectric slabs, each with slightly different permittivities. Collaction (point-matching) techniques are used to match boundary conditions at each interface within the dielectric loaded aperture section and two-dimensional Fourier transforms are used to match boundary conditions at each interface in the covering layer. Matrix techniques are used to handle an arbitrary number of layers in either region. A large number of experimental measurements of input admittance and far-field radiation pattern measurements are presented for three different aperture configurations, with and without a covering dielectric layer. A computer program is described that can handle the computations. The program is written in FORTRAN IV for a Control Data Corporation 6600 machine. Computed values of input admittance and far-field radiation patterns are presented. (Author).
Download or read book A Dielectric loaded Leaky Wave Antenna written by Jorgen Aasted and published by . This book was released on 1961 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design and the measured performance are described of a flat, leaky-wave antenna in which the inductive, leaky surface is backed with a slab of dielectric. The analysis is based on a transverse resonance analysis which determines the physical dimensions of the antenna for a certain specified aperture distribution. An antenna was built to compare the theoretical behavior with the measured performance. Two ways of forming the dielectric to the antenna were tested. When the dielectric was molded in place the radiation pattern agreed very well with the theoretically predicted pattern, but high losses in the casting resin gave a lower gain for the antenna than anticipated. For a machined piece of dielectric, the radiation pattern was not as close to the predicted pattern as for the molded sample, but the gain was close to the predicted value. The antenna consists of a 28-by-18-inch through filled with a dielectric material over which a sheet of parallel wires is strung. At the design frequency, 4.75 gc, the antenna radiates a pencil beam 9.4 by 8.3 degrees wide at an angle of 54 degrees measured from the normal to the inductive surface. The beam can be scanned from approximately 75 degrees down to 12 degrees from the normal to the aperture by changing the frequency from 5.25 gc to 4.20 gc. (Author).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aperture Excited Dielectric Antennas written by and published by . This book was released on 1974 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dielectric and Dielectric Loaded Antennas written by Rajeswari Chatterjee and published by John Wiley & Sons. This book was released on 1985-11-07 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive survey of research on dielectric and dielectric-loaded antennas, providing a critical review of work carried out over the past thirty-five years. Covers a wide range of antenna shapes, types, and practical applications at microwave and millimetre wave frequencies.
Download or read book Fractal Apertures in Waveguides Conducting Screens and Cavities written by Basudeb Ghosh and published by Springer. This book was released on 2014-06-12 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the design and analysis of fractal apertures in waveguides, conducting screens and cavities using numerical electromagnetics and field-solvers. The aim is to obtain design solutions with improved accuracy for a wide range of applications. To achieve this goal, a few diverse problems are considered. The book is organized with adequate space dedicated for the design and analysis of fractal apertures in waveguides, conducting screens and cavities, microwave/millimeter wave applications followed by detailed case-study problems to infuse better insight and understanding of the subject. Finally, summaries and suggestions are given for future work. Fractal geometries were widely used in electromagnetics, specifically for antennas and frequency selective surfaces (FSS). The self-similarity of fractal geometry gives rise to a multiband response, whereas the space-filling nature of the fractal geometries makes it an efficient element in antenna and FSS unit cell miniaturization. Until now, no efforts were made to study the behavior of these fractal geometries for aperture coupling problems. The aperture coupling problem is an important boundary value problem in electromagnetics and used in waveguide filters and power dividers, slotted ground planes, frequency selective surfaces and metamaterials. The present book is intended to initiate a study of the characteristics of fractal apertures in waveguides, conducting screens and cavities. To perform a unified analysis of these entirely dissimilar problems, the “generalized network formulation of the aperture problems” by Mautz and Harrington was extended to multiple-aperture geometry. The authors consider the problem of coupling between two arbitrary regions coupled together via multiple apertures of arbitrary shape. MATLAB codes were developed for the problems and validated with the results available in the literature as well as through simulations on ANSOFT's HFSS.
Download or read book Radiation from Slot fed Dielectric Slabs written by Alfred T. Villeneuve and published by . This book was released on 1972 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report contains analyses of the radiation characteristics of grounded dielectric slabs fed by slots in the groundplane. Two configurations are examined, one in which a semi-infinite slab covers the slot, a second in which a finite slab does not extend over the slot. The slots are parallel to the slab edges so that only TM mode propagation is considered. Integral equations are derived for the fields at the ends of the slabs and approximate solutions are obtained. Numerical results in the form of radiation patterns are given for the case of the semi-infinite slab. It is found that the feed pattern is very close to the space-wave that would exist if the slab were infinite, but differs from it in the region near the horizon. The results can be applied to studies of electronic scanning of finite arrays of slots in the presence of surface wave structures. Recommendations for further study are included. (Author).
Download or read book Microwave Horns and Feeds written by A. David Olver and published by IET. This book was released on 1994 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph is devoted to the theory, design, performance and application of microwave horns and feeds for reflector antennas. It is a collaboration between the microwave antenna group at Queen Mary and Westfield College and the electromagnetic group at the University of Winnipeg, Canada.
Download or read book Input Admittance of a Rectangular Waveguide fed Aperture Antenna Radiating Into an Inhomogeneous Lossy Dielectric Slab written by Calvin Thomas Swift and published by . This book was released on 1967 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radiation by Dielectric loaded Antennas with Airgaps written by Sabah Jawad Towaij and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NASA Technical Note written by and published by . This book was released on 1973 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Substrate Integrated Millimeter Wave Antennas for Next Generation Communication and Radar Systems written by Zhi Ning Chen and published by John Wiley & Sons. This book was released on 2021-04-08 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Substrate-Integrated Millimeter-Wave Antennas for Next-Generation Communication and Radar Systems The first and only comprehensive text on substrate-integrated mmW antenna technology, state-of-the-art antenna design, and emerging wireless applications Substrate-Integrated Millimeter-Wave Antennas for Next-Generation Communication and Radar Systems elaborates the most important topics related to revolutionary millimeter-wave (mmW) technology. Following a clear description of fundamental concepts including substrate-integrated waveguides and loss analysis, the text treats key design methods, prototyping techniques, and experimental setup and testing. The authors also highlight applications of mmW antennas in 5G wireless communication and next-generation radar systems. Readers are prepared to put techniques into practice through practical discussions of how to set up testing for impedance matching, radiation patterns, gain from 24GHz up to 325 GHz, and more. This book will bring readers state-of-the-art designs and recent progress in substrate-integrated mmW antennas for emerging wireless applications. Substrate-Integrated Millimeter-Wave Antennas for Next-Generation Communication and Radar Systems is the first comprehensive text on the topic, allowing readers to quickly master mmW technology. This book: Introduces basic concepts such as metamaterials Huygens’s surface, zero-index structures, and pattern synthesis Describes prototyping in the form of fabrication based on printed-circuit-board, low-temperature-co-fired-ceramic and micromachining Explores applications for next-generation radar and imaging systems such as 24-GHz and 77-GHz vehicular radar systems Elaborates design methods including waveguide-based feeding network, three-dimensional feeding structure, dielectric loaded aperture antenna element, and low-sidelobe synthesis The mmW is one of today’s most important emerging technologies. This book provides graduate students, researchers, and engineers with the knowledge they need to deploy mmW systems and develop new antenna designs with low cost, low loss, and low complexity.
Download or read book Dielectric Resonator Antennas written by Kwai Man Luk and published by Research Studies Press Limited. This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of dielectric resonator as a resonant antenna was proposed in 1983. Due to the absence of metallic loss, the dielectric resonator antenna (DRA) is highly efficient when operated at millimetre wave frequencies. With the use of high dielectric constant material, the DRA can also be used as a small and low profile antenna operated at low microwave frequencies. Low cost dielectric materials are now easily available commercially, encouraging more antenna engineers to design communication systems with DRAs.
Download or read book Aperture Antennas for Millimeter and Sub Millimeter Wave Applications written by Artem Boriskin and published by Springer. This book was released on 2017-09-05 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the technology of millimetre waves and Terahertz (THz) antennas. It highlights the importance of moderate and high-gain aperture antennas as key devices for establishing point-to-point and point-to-multipoint radio links for far-field and near-field applications, such as high data-rate communications, intelligent transport, security imaging, exploration and surveillance systems. The book provides a comprehensive overview of the key antenna technologies developed for the mm wave and THz domains, including established ones – such as integrated lens antennas, advanced 2D and 3D horn antennas, transmit and reflect arrays, and Fabry-Perot antennas – as well as emerging metasurface antennas for near-field and far-field applications. It describes the pros and cons of each antenna technology in comparison with other available solutions, a discussion supplemented by practical examples illustrating the step-by-step implementation procedures for each antenna type. The measurement techniques available at these frequency ranges are also presented to close the loop of the antenna development cycle. In closing, the book outlines future trends in various antenna technologies, paving the way for further developments. Presenting content originating from the five-year ESF research networking program ‘Newfocus’ and co-authored by the most active and highly cited research groups in the domain of mm- and sub-mm-wave antenna technologies, the book offers a valuable guide for researchers and engineers in both industry and academia.
Download or read book Fundamentals of Aperture Antennas and Arrays written by Trevor S. Bird and published by John Wiley & Sons. This book was released on 2016-01-19 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended as an advanced text for courses in antennas, with a focus on the mature but vital background field of aperture antennas. The book is aimed at final year, MSc, PhD and Post-Doctoral students, as well as readers who are moving from academia into industry, beginning careers as wireless engineers, system designers, in R&D, or for practising engineers. It assumes the reader has undertaken an earlier course of study on Maxwell's equations, fields and waves. Some of these topics are summarised in the early few chapters in order to provide continuity and background for the remaining chapters. The aperture antennas covered include the main types of horns, reflectors and arrays as well as microstrip patches, reflectarrays and lenses. To provide more than a superficial treatment of arrays, the topic of mutual coupling is covered in greater detail than most similar books in the area. Also included is an introduction to arrays on non-planar surfaces, which is of importance for applications that involve curved surfaces such as in aerodynamics or for making aperture antennas unobtrusive. A chapter is included on some modern aperture antennas to illustrate design techniques beyond the most common types of aperture antennas described in the early chapters. This is to show where advances have recently been made and where they could be improved in the future. Also included are selected topics of a practical nature for aperture antennas, namely fabrication and measurement.
Download or read book Electromagnetic Waveguides written by S. F. Mahmoud and published by IET. This book was released on 1991 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: A textbook for an introductory graduate course in electromagnetic waveguides, covering such types as low attenuation, dielectric, and the natural wave guides in the ionosphere and in mine tunnels. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book Handbook of Reflector Antennas and Feed Systems Volume II Feed Systems written by Lotfollah Shafai and published by Artech House. This book was released on 2013-07-01 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first truly comprehensive and most up-to-date handbook available on modern reflector antennas and feed sources for diversified space and ground applications. There has never been such an all-encompassing reflector handbook in print, and no currently available title offers coverage of such recent research developments. The Handbook consists of three volumes. Volume II focuses on feed sources. Reflector antennas are extraordinary devices that combine high gain with geometrical simplicity, and can operate in broad frequency bands. Their performance, however, depends on the electrical characteristics of the feed system with which they operate. This comprehensive volume provides you with a solid understanding of feed system theory, design, and analysis. Featuring chapters authored by experts in each aspect of feed systems, this book takes you from fundamental mathematical techniques, electrically small and large dual reflectors, feed geometry and telemetry, tracking and command antennas, and more. Throughout the book numerous examples are provided to guide you in the practical aspects of feed design.
