Download or read book Analysis of a Generalized Dual Reflector Antenna System Using Physical Optics written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-30 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflector antennas are widely used in communication satellite systems because they provide high gain at low cost. Offset-fed single paraboloids and dual reflector offset Cassegrain and Gregorian antennas with multiple focal region feeds provide a simple, blockage-free means of forming multiple, shaped, and isolated beams with low sidelobes. Such antennas are applicable to communications satellite frequency reuse systems and earth stations requiring access to several satellites. While the single offset paraboloid has been the most extensively used configuration for the satellite multiple-beam antenna, the trend toward large apertures requiring minimum scanned beam degradation over the field of view 18 degrees for full earth coverage from geostationary orbit may lead to impractically long focal length and large feed arrays. Dual reflector antennas offer packaging advantages and more degrees of design freedom to improve beam scanning and cross-polarization properties. The Cassegrain and Gregorian antennas are the most commonly used dual reflector antennas. A computer program for calculating the secondary pattern and directivity of a generalized dual reflector antenna system was developed and implemented at LeRC. The theoretical foundation for this program is based on the use of physical optics methodology for describing the induced currents on the sub-reflector and main reflector. The resulting induced currents on the main reflector are integrated to obtain the antenna far-zone electric fields. The computer program is verified with other physical optics programs and with measured antenna patterns. The comparison shows good agreement in far-field sidelobe reproduction and directivity. Acosta, Roberto J. and Lagin, Alan R. Glenn Research Center RTOP 679-40-00...
Download or read book Analysis of a Generalized Dual Reflector Antenna System Using Physical Optics written by Roberto J. Acosta and published by . This book was released on 1992 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Reflector Antennas written by W. V. T. Rusch and published by Academic Press. This book was released on 2013-10-22 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis of Reflector Antennas provides information pertinent to the analysis of reflector-antenna systems. This book provides an understanding of how design data have been and can be derived. Organized into four chapters, this book begins with an overview of the history of focusing reflector-antenna systems characterized by a highly variable level of general interest. This text then examines the solutions of the scalar Helmholtz equation in rectangular and spherical coordinates. Other chapters consider antenna performance described in terms of several fundamental properties, including capture area, directivity, gain, beam efficiency, aperture efficiency, polarization, effective noise temperature, and phase center. This book discusses as well the resulting functional dependence between axial ratio and component amplitude, which is the same as that between voltage standing wave ratio and voltage reflection coefficient. The final chapter deals with the role of the special-purpose digital computers. This book is a valuable resource for research and development engineers.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1993 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on with total page 1308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physical Optics Analysis of Reflector Antennas written by Vania Giacomelli and published by . This book was released on 2001 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Reflector Antennas and Feed Systems Volume I Theory and Design of Reflectors written by Satish K. Sharma and published by Artech House. This book was released on 2013-07-01 with total page 323 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 I provides a unique combination of theoretical underpinnings with design considerations and techniques. The need for knowledge in reflector antennas has grown steadily over the last two decades due to increased use in space and ground applications, as well as their high gain and wide bandwidth capabilities at relatively low cost. This volume brings you to the leading edge of developments in the field related to numerical techniques, classical reflector geometries, adaptive reflector antennas, shaped reflectors, bifocal and bicollimated dual reflectors, advanced reflectors, and reflect arrays. A must-have reference for both practicing engineers as well as academic researchers.
Download or read book Adventures in Contemporary Electromagnetic Theory written by Tom G. Mackay and published by Springer Nature. This book was released on 2023-07-31 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the most recent advances in electromagnetic theory, motivated and partly informed by developments in engineering science and nanotechnology. The collection of chapters provided in this edited book, authored by leading experts in the field, offers a bird’s eye view of recent progress in electromagnetic theory, spanning a wide range of topics of current interest, ranging from fundamental issues to applications.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1992-06 with total page 1516 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of Lewis Research Center Technical Publications Announced in 1992 written by and published by . This book was released on 1993 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Antennas in Wireless Communications written by Lal Chand Godara and published by CRC Press. This book was released on 2018-10-03 with total page 936 pages. Available in PDF, EPUB and Kindle. Book excerpt: The move toward worldwide wireless communications continues at a remarkable pace, and the antenna element of the technology is crucial to its success. With contributions from more than 30 international experts, the Handbook of Antennas in Wireless Communications brings together all of the latest research and results to provide engineering professionals and students with a one-stop reference on the theory, technologies, and applications for indoor, hand-held, mobile, and satellite systems. Beginning with an introduction to wireless communications systems, it offers an in-depth treatment of propagation prediction and fading channels. It then explores antenna technology with discussion of antenna design methods and the various antennas in current use or development for base stations, hand held devices, satellite communications, and shaping beams. The discussions then move to smart antennas and phased array technology, including details on array theory and beamforming techniques. Space diversity, direction-of-arrival estimation, source tracking, and blind source separation methods are addressed, as are the implementation of smart antennas and the results of field trials of systems using smart antennas implemented. Finally, the hot media topic of the safety of mobile phones receives due attention, including details of how the human body interacts with the electromagnetic fields of these devices. Its logical development and extensive range of diagrams, figures, and photographs make this handbook easy to follow and provide a clear understanding of design techniques and the performance of finished products. Its unique, comprehensive coverage written by top experts in their fields promises to make the Handbook of Antennas in Wireless Communications the standard reference for the field.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1992 with total page 1720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design and Rigorous Analysis of Generalized Axially symmetric Dual reflector Antennas written by Fernando J. S. Moreira and published by . This book was released on 1997 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Publications in Engineering written by and published by . This book was released on 1993 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Antennas written by Yi Huang and published by John Wiley & Sons. This book was released on 2021-09-02 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antennas From Theory to Practice Comprehensive coverage of the fundamentals and latest developments in antennas and antenna design In the newly revised Second Edition of Antennas: From Theory to Practice, renowned researcher, engineer, and author Professor Yi Huang delivers comprehensive and timely coverage of issues in modern antenna design and theory. Practical and accessible, the book is written for engineers, researchers, and students who work with radio frequency/microwave engineering, radar, and radio communications. The book details the basics of transmission lines, radiowaves and propagation, antenna theory, antenna analysis and design using industrial standard design software tools and the theory of characteristic modes, antenna measurement equipment, facilities, and techniques. It also covers the latest developments in special topics, like small and mobile antennas, wide- and multi-band antennas, automotive antennas, RFID, UWB, metamaterials, reconfigurable and MIMO antennas, and more. The new edition includes up to date information on a wide variety of newly relevant topics and trends, like adaptive impedance matching, the theory of characteristic modes, antenna materials and fabrication processes, and over-the-air (OTA) antenna system measurements. Many questions and examples are provided which enhances the learning experience. The book covers: An introduction to circuit concepts and transmission lines, including lumped and distributed element systems, transmission line theory, and the Smith Chart An exploration of field concepts and radiowaves, including wave equations and solutions and radiowave propagation mechanisms, characteristics, and models Discussions of antenna basics and popular antennas, including wire-type antennas, aperture-type antennas, and antenna arrays Information about antenna manufacturing and measurements, including antenna measurement facilities and methods The use of industrial standard simulation tools for antenna design and analysis Perfect for engineers and researchers who work in RF engineering or radar and radio communications, Antennas: From Theory to Practice, Second Edition will also earn a place on the bookshelves of university students seeking a concise and practical introduction to the basics of antennas and antenna design.
