Download or read book Modeling and Control of Antennas and Telescopes written by Wodek Gawronski and published by Springer Science & Business Media. This book was released on 2008-07-11 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanical engineering, and engineering discipline born of the needs of the industrial revolution, is once again asked to do its substantial share in the call for industrial renewal. The general call is urgent as we face profound issues of productivity and competitiveness that require engineering solutions, among others. The Mechanical Engineering Series is a series featuring graduate texts and research monographs intended to address the need for information in contemporary areas of mechanical engineering. The series is conceived as a comprehensive one that covers a broad range of c- centrations important to mechanical engineering graduate education and research. We are fortunate to have a distinguished roster of series editors, each an expert in one of the areas of concentration. The names of the series editors are listed on page vi of this volume. The areas of concentration are applied mechanics, biomechanics, computational mechanics, dynamic systems and control, energetics, mechanics of materials, processing, thermal science, and tribology. Preface This book is based on my experience with the control systems of antennas and radiotelescopes. Overwhelmingly, it is based on experience with the NASA Deep Space Network (DSN) antennas. It includes modeling the antennas, developing control algorithms, eld testing, system identi cation, performance evaluation, and 1 troubleshooting. My previous book emphasized the theoretical aspects of antenna control engineering, while this one describes the application part of the antenna control engineering.

Download or read book Partial Differential Equations VIII written by M.A. Shubin and published by Springer. This book was released on 1995-12-01 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume of the EMS contains three articles, on linear overdetermined systems of partial differential equations, dissipative Schroedinger operators, and index theorems. Each article presents a comprehensive survey of its subject, discussing fundamental results such as the construction of compatibility operators and complexes for elliptic, parabolic and hyperbolic coercive problems, the method of functional models and the Atiyah-Singer index theorem and its generalisations. Both classical and recent results are explained in detail and illustrated by means of examples.

Download or read book Integrated Modeling of Telescopes written by Torben Andersen and published by Springer Science & Business Media. This book was released on 2011-06-23 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground- or space-based telescopes are becoming increasingly more complex and construction budgets are typically in the billion dollar range. Facing costs of this magnitude, availability of engineering tools for prediction of performance and design optimization is imperative. Establishment of simulation models combining different technical disciplines such as Structural Dynamics, Control Engineering, Optics and Thermal Engineering is indispensable. Such models are normally called Integrated Models because they involve many different disciplines. The models will play an increasingly larger role for design of future interdisciplinary optical systems in space or on ground. The book concentrates on integrated modeling of optical and radio telescopes but the techniques presented will be applicable to a large variety of systems. Hence, the book will be of interest to optical and radio telescope designers, designers of spacecrafts that include optical systems, and to designers of various complex defense systems. The book may also find use as a textbook for undergraduate and graduate courses within the field. "Adaptive Optics" is an exciting and relatively new field, originally dedicated to correction for blurring when imaging through the atmosphere. Although this objective is still of high importance, the concept of Adaptive Optics has recently evolved further. Today, the objective is not only to correct for atmospheric turbulence effects but also for a range of static and dynamical telescope aberrations. The notion of adaptive optics has expanded to the field of "Wavefront Control", correcting for a variety of system aberrations. Wavefront control systems maintain form and position of optical elements with high precision under static and dynamical load. In many ways, such systems replace the steel structures of traditional optical systems, thereby providing much lighter systems with a performance not possible before. Integrated Modeling is the foremost tool for studies of Wavefront Control for telescopes and complex optics and is therefore now of high importance. Springer has recently published two books on telescopes, "Reflecting Telescope Optics" by R. Wilson, and "The Design and Construction of Large Optical Telescopes" by P. Bely. Noting that a new (and expensive) generation of Extremely Large Telescopes with apertures in the 30-100 m range is on the way, the present book on integrated modeling is a good match to the existing books and an appropriate specialization and continuation of some subjects dealt with in those books.

Download or read book Thermal Design and Thermal Behaviour of Radio Telescopes and their Enclosures written by Albert Greve and published by Springer Science & Business Media. This book was released on 2010-03-17 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio telescopes as well as communication antennas operate under the influence of gravity, temperature and wind. Among those, temperature influences may degrade the performance of a radio telescope through transient changes of the focus, pointing, path length and sensitivity, often in an unpredictable way. Thermal Design and Thermal Behaviour of Radio Telescopes and their Enclosures reviews the design and construction principles of radio telescopes in view of thermal aspects and heat transfer with the variable thermal environment; it explains supporting thermal model calculations and the application and efficiency of thermal protection and temperature control; it presents many measurements illustrating the thermal behaviour of telescopes in the environment of their observatory sites. The book benefits scientists and radio/communication engineers, telescope designers and construction firms as well as telescope operators, observatory staff, but also the observing astronomer who is directly confronted with the thermal behaviour of a telescope.

Download or read book Modeling and Control of Antennas and Telescopes written by Wodek Gawronski and published by Springer. This book was released on 2008-11-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanical engineering, and engineering discipline born of the needs of the industrial revolution, is once again asked to do its substantial share in the call for industrial renewal. The general call is urgent as we face profound issues of productivity and competitiveness that require engineering solutions, among others. The Mechanical Engineering Series is a series featuring graduate texts and research monographs intended to address the need for information in contemporary areas of mechanical engineering. The series is conceived as a comprehensive one that covers a broad range of c- centrations important to mechanical engineering graduate education and research. We are fortunate to have a distinguished roster of series editors, each an expert in one of the areas of concentration. The names of the series editors are listed on page vi of this volume. The areas of concentration are applied mechanics, biomechanics, computational mechanics, dynamic systems and control, energetics, mechanics of materials, processing, thermal science, and tribology. Preface This book is based on my experience with the control systems of antennas and radiotelescopes. Overwhelmingly, it is based on experience with the NASA Deep Space Network (DSN) antennas. It includes modeling the antennas, developing control algorithms, eld testing, system identi cation, performance evaluation, and 1 troubleshooting. My previous book emphasized the theoretical aspects of antenna control engineering, while this one describes the application part of the antenna control engineering.

Download or read book Modeling and Analysis of the Dss 14 Antenna Control System written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-05 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: An improvement of pointing precision of the DSS-14 antenna is planned for the near future. In order to analyze the improvement limits and to design new controllers, a precise model of the antenna and the servo is developed, including a finite element model of the antenna structure and detailed models of the hydraulic drives and electronic parts. The DSS-14 antenna control system has two modes of operation: computer mode and precision mode. The principal goal of this investigation is to develop the model of the computer mode and to evaluate its performance. The DSS-14 antenna computer model consists of the antenna structure and drives in azimuth and elevation. For this model, the position servo loop is derived, and simulations of the closed-loop antenna dynamics are presented. The model is significantly different from that for the 34-m beam-waveguide antennas. Gawronski, W. and Bartos, R. Jet Propulsion Laboratory RTOP 314-30-55-02-19...

Download or read book Modeling and Shape Control of a Segmented mirror Telescope written by Alain Carrier and published by . This book was released on 1990 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Paraboloidal Reflector Antenna in Radio Astronomy and Communication written by Jacob W. M. Baars and published by Springer Science & Business Media. This book was released on 2007-07-16 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio astronomers have developed techniques of calibration of large reflector antennas with radio astronomical methods, but these have not been comprehensively described. This text aims to fill this gap, taking a practical approach to the characterisation of antennas. All calculations and results in the form of tables and figures have been made with Mathematica by Wolfram Research. The reader can use the procedures for the implementation of his own input data.

Download or read book Antenna and EM Modeling with MATLAB Antenna Toolbox written by Sergey N. Makarov and published by John Wiley & Sons. This book was released on 2021-05-11 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: ANTENNA AND EM MODELING WITH MATLAB ANTENNA TOOLBOX™ An essential text to MATLAB Antenna Toolbox™ as accessible and easy-to-use full-wave antenna modeling tool Antenna and EM Modeling with MATLAB Antenna Toolbox™ is a textbook on antennas intended for a one semester course. The core philosophy is to introduce the key antenna concepts and follow them up with full-wave modeling and optimization in the MATLAB Antenna Toolbox™. Such an approach will enable immediate testing of theoretical concepts by experimenting in software. It also provides the direct path to research work. The fundamental families of antennas — dipoles, loops, patches, and traveling wave antennas — are discussed in detail, together with the respective antenna arrays. Using antenna parameters such as impedance, reflection coefficient, efficiency, directivity, and gain, the reader is introduced to the different ways of understanding the performance of an antenna. Written for senior undergraduates, graduates as well as RF/Antenna engineers, Antenna and EM Modeling with Antenna Toolbox™ is a resource that: Provides 14 video assisted laboratories on using Antenna Toolbox™ Includes approximately 50 real-world examples in antenna and array design Offers approximately 200 homework problems Provides multiple ready-to-use standalone MATLAB® scripts

Download or read book Integrated Modeling to Facilitate Control Architecture Design for Lightweight Space Telescopes written by Lucy Elizabeth Cohan and published by . This book was released on 2007 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: (cont.) As the areal density of the mirror decreases, the cost due to mass decreases, but the cost due to control increases because more control is required to meet the requirements. Therefore, a balance between lightweight systems and control is sought to give the best overall performance. Additionally, there are many different types of control that could be used on the system, thus finding optimal combinations of controllers, sensors, actuators, and bandwidths is a daunting task. The integrated modeling technique allows the designer to examine the effects of structural parameters and requirements on the control system architecture and the performance metrics. The ability to determine favorable control system architectures early in the design process will allow new technologies to be pushed further, while still maintaining confidence that the system will perform as expected.

Download or read book Statics and Dynamics Simulation of a Multi tethered Aerostat System written by Xiaohua Zhao and published by . This book was released on 2004 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Essential Radio Astronomy written by James J. Condon and published by Princeton University Press. This book was released on 2016-04-05 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ideal text for a one-semester course in radio astronomy Essential Radio Astronomy is the only textbook on the subject specifically designed for a one-semester introductory course for advanced undergraduates or graduate students in astronomy and astrophysics. It starts from first principles in order to fill gaps in students' backgrounds, make teaching easier for professors who are not expert radio astronomers, and provide a useful reference to the essential equations used by practitioners. This unique textbook reflects the fact that students of multiwavelength astronomy typically can afford to spend only one semester studying the observational techniques particular to each wavelength band. Essential Radio Astronomy presents only the most crucial concepts—succinctly and accessibly. It covers the general principles behind radio telescopes, receivers, and digital backends without getting bogged down in engineering details. Emphasizing the physical processes in radio sources, the book's approach is shaped by the view that radio astrophysics owes more to thermodynamics than electromagnetism. Proven in the classroom and generously illustrated throughout, Essential Radio Astronomy is an invaluable resource for students and researchers alike. The only textbook specifically designed for a one-semester course in radio astronomy Starts from first principles Makes teaching easier for astronomy professors who are not expert radio astronomers Emphasizes the physical processes in radio sources Covers the principles behind radio telescopes and receivers Provides the essential equations and fundamental constants used by practitioners Supplementary website includes lecture notes, problem sets, exams, and links to interactive demonstrations An online illustration package is available to professors

Download or read book Advanced Antenna Modeling written by Marcel De Canck and published by . This book was released on 2019-09-09 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the last two decades, computerized antenna modeling has advanced greatly. Modeling, a powerful tool in Amateur Radio, can help you to design antennas and optimize their performances.Advanced Antenna Modeling is in every respect the guide to using modeling software for designing, optimizing and evaluating antennas. It provides a detailed explanation to use EZNEC, the most popular antenna modeling program used by radio amateurs today, and thoroughly how to optimize the model with the AutoEZ application in conjunction with EZNEC.With Advanced Antenna Modeling, you can evaluate and adjust pre-designed models and create your own models. Step by step you are guided and explained to become familiarized to important functions and procedures along the way. As you progress, you'll discover the strength of modeling with the extra use of various AutoEZ features.View the book concept with the article "Using AutoEZ with Antenna Modeling" It's available on the website www.on5au.be.Dan Maguire, AC6LA -- Both the scope and depth of material in Marcel's Advanced Antenna Modeling book are truly amazing. If you enjoy modeling, as I do, reading this book will spark many thoughts of "That's very clever!" and "I had no idea that was possible!" John Devoldere, ON4UN -- I highly recommend Advanced Antenna Modeling to get experience with all the clever features AutoEZ offers. It is amazing to discover how Marcel manages to reposition a rather complex antenna structure. He is a master to explain in a clear way many other AutoEZ specific tricks.The Author, ON5AU -- From the start as radio ham, I was always interested in the know-how of antennas and most of my antennas were and still are home brew, such as cubical quads, Yagis, delta loops, multiband dipoles, ground plains, etc.

Download or read book Practical Antenna Models written by Marcel De canck and published by . This book was released on 2021-08-30 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Antenna Modeling Made Easy and Optimized By using variables, equations, and formulas Over the last three decades, computerized antenna modeling has advanced greatly. Modeling, a powerful tool in Amateur Radio, can help you to design antennas and optimize their performances. Today, the EZNEC program is widely used worldwide. A lot was, and still is written about this program in many books, magazines, and on the internet. Example EZNEC models are widely and easily found and available. However, EZNEC lacks one option: optimizing the model. To allow optimizing, you need the use of variables and formulas. This lack is solved by the author of the AutoEZ application, Dan Maguire, AC6LA. Whenever you Google "AutoEZ models" or "Optimizing Antenna models," you will be disappointed about the results. Nearly the only source about optimizing an antenna is found at the website of Dan Maguire and my website on5au.be, and my book publications: "Advanced Antenna Modeling" and "Practical Antenna Models - Volume 1". This new "Practical Antenna Models -Volume 2" handles mainly, for the most part, vertically polarized antennas, such as groundplanes, verticals, 5/8 wavelength multiband, Tower (pylon) models, mutual coupling between antennas, J-pole, matching circuits, etc. Again, EZNEC and AutoEZ models are intensively used, step by step, fully explained, and many AutoEZ tricks revealed.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technology for Large Space Systems written by and published by . This book was released on 1990 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Reconstruction and Multivariable Control for Force Actuated Thin Facesheet Adaptive Optics written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-11-18 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Multiple Mirror Telescope (MMT) under development at the University of Arizona takes a new approach in adaptive optics placing a large (0.65 m) force-actuated, thin facesheet deformable mirror at the secondary of an astronomical telescope, thus reducing the effects of emissivity which are important in IR astronomy. However, The large size of the mirror and low stiffness actuators used drive the natural frequencies of the mirror down into the bandwidth of the atmospheric distortion. Conventional adaptive optics takes a quasi-static approach to controlling the, deformable mirror. However, flexibility within the control bandwidth calls for a new approach to adaptive optics. Dynamic influence functions are used to characterize the influence of each actuator on the surface of the deformable mirror. A linearized model of atmospheric distortion is combined with dynamic influence functions to produce a dynamic reconstructor. This dynamic reconstructor is recognized as an optimal control problem. Solving the optimal control problem for a system with hundreds of actuators and sensors is formidable. Exploiting the circularly symmetric geometry of the mirror, and a suitable model of atmospheric distortion, the control problem is divided into a number of smaller decoupled control problems using circulant matrix theory. A hierarchic control scheme which seeks to emulate the quasi-static control approach that is generally used in adaptive optics is compared to the proposed dynamic reconstruction technique. Although dynamic reconstruction requires somewhat more computational power to implement, it achieves better performance with less power usage, and is less sensitive than the hierarchic technique. Grocott, Simon C. O. and Miller, David W. Langley Research Center; Marshall Space Flight Center ADAPTIVE OPTICS; DEFORMABLE MIRRORS; TELESCOPES; DYNAMIC CONTROL; OPTIMAL CONTROL; ACTUATORS; ATMOSPHERIC MODELS; BANDWIDTH; DISTORTION; EMISSIVITY; FLEXIBILITY; INFRARED ASTRONOMY; MATRI...