Download or read book A Frequency Reconfigurable Circularly Polarized Microstrip Patch Antenna Using Liquid Metal Microswitches written by Steven Christopher Yee and published by . This book was released on 2013 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reconfigurable antennas with adaptable frequency, pattern, and polarization offer flexibility and size reduction for wireless systems that must increasingly execute multiple missions with less volume. These antennas will also complement anticipated cognitive radio systems, which promise more efficient use of the electromagnetic spectrum. Microscale liquid metal switches are proposed to overcome the series loss, mechanical fatigue, and limited power handling reliability of common methods of antenna reconfiguration such as semiconductor diodes and microelectromechanical switches. The proposed microswitches consist of mercury droplets that selectively connect solid metal traces. Both fluidic and electrostatic switch actuation mechanisms are investigated, and an electrostatic switch is demonstrated. Electrostatically actuated switches are designed into a compact single-feed patch antenna configurable between two communication frequency bands and a GPS band with different circular polarizations. The antenna topology is based on a corner truncated square patch with switched sets of extensions to achieve resonant frequency and axial ratio control. Measurements of reconfigurable prototypes demonstrate frequency and polarization configurability in good agreement with full-wave simulations. The proposed reconfiguration mechanism is compared to other methods, and future directions for the integration of microfluidics in reconfigurable radio frequency systems are proposed.
Download or read book Wideband Multiband and Smart Reconfigurable Antennas for Modern Wireless Communications written by Matin, Mohammad A. and published by IGI Global. This book was released on 2015-08-26 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modern society thrives on communication that is instant and available at all times, a constant exchange of information that encompasses everything from video streaming to GPS navigation. Experts even suggest that in the near future everything from our cars to our kitchen appliances will be connected to the internet, a feat that would not be possible without advanced wireless technology. Wideband, Multiband, and Smart Reconfigurable Antennas for Modern Wireless Communications showcases current trends and novel approaches in the design and analysis of the antennas that make wireless applications possible, while also identifying unique integration opportunities for antennas and wireless applications to work together. By featuring both theoretical and experimental approaches to integration, this book highlights specific design issues to assist a wide-range of readers including students, researchers, academics, and industry practitioners. This publication features chapters on a broad scope of topics including algorithms and antenna optimization, wireless infrastructure development, wireless applications of intelligent algorithms, antenna architecture, and antenna reconfiguration techniques.
Download or read book Reconfigurable Wideband Circularly Polarized Microstrip Patch Antenna for Wireless Applications written by Ahmed Khidre and published by . This book was released on 2012 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, developments of rectangular microstrip patch antenna to have circular polarization agility with wideband performance, for wireless applications are presented. First, a new technique to achieve circularly polarized (CP) probe feed single-layer microstrip patch antenna with wideband characteristics is proposed. The antenna is a modified form of the popular E-shaped patch, used to broaden the impedance bandwidth of a basic rectangular patch antenna. This is established by letting the two parallel slots of the E-patch unequal. Thus, by introducing asymmetry two orthogonal currents on the patch are excited and circularly polarized fields are realized. The proposed technique exhibits the advantage of the simplicity inherent in the E-shaped patch design. It requires only slot lengths, widths, and position parameters to be determined. Also, it is suitable for later adding the reconfigurable capability. With the aid of full-wave simulator Ansoft HFSS, investigations on the effect of various dimensions of the antenna have been carried out via parametric analysis. Based on these investigations, a design procedure for a CP E-shaped patch is summarized. Various design examples with different substrate thicknesses and material types are presented and compared, with CP U-slot patch antennas, recently proposed in the literature. A prototype has been constructed following the suggested design procedure to cover the IEEE 802.11b/g WLAN band. The performance of the fabricated antenna was measured and compared with the simulation results for the reflection coefficient, axial ratio, radiation pattern, and antenna gain. Good agreement is achieved between simulation and measured results demonstrating a high gain and wideband performance. Second, a polarization reconfigurable single feed E-shaped patch antenna with wideband performance is proposed. The antenna is capable of switching from right-hand circular polarization (RHCP) to left-hand circular polarization (LHCP) and vice versa, with the aid of two RF PIN diodes that act as RF switches. The proposed structure which is simple; consists of a single-layer single fed radiating E-shaped patch and RF switch placed on each of its slots at an appropriate location. The design targets WLAN IEEE 802.11b/g frequency band (2.4- 2.5 GHz) as one example of the wireless applications. The idea is based on the first proposed design. In other words, if one of the switches is ON and the other is OFF, the two slot lengths will become effectively unequal and circular polarization will be obtained. If the states of the two switches are reversed, circular polarization with opposite orientation will be obtained at the same frequency band. Full-wave simulator Ansoft HFSS is again used for the analysis. Complete detailed DC biasing circuit of the switches for integration with the antenna is presented. Also, characterizations of the microwave components used in the biasing circuit are discussed. Antenna prototype has been fabricated and tested. Simulation results along with the measured one, for the reflection coefficient, axial ratio, radiation pattern, and antenna gain agree well, showing wide bandwidth and high gain for the two circularly polarized modes.
Download or read book Advances in Communication Devices and Networking written by Rabindranath Bera and published by Springer. This book was released on 2019-02-15 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book covers recent trends in the field of devices, wireless communication and networking. It presents the outcomes of the International Conference in Communication, Devices and Networking (ICCDN 2018), which was organized by the Department of Electronics and Communication Engineering, Sikkim Manipal Institute of Technology, Sikkim, India on 2–3 June, 2018. Gathering cutting-edge research papers prepared by researchers, engineers and industry professionals, it will help young and experienced scientists and developers alike to explore new perspectives, and offer them inspirations on addressing real-world problems in the field of electronics, communication, devices and networking.
Download or read book Introduction to RF Equipment and System Design written by Pekka Eskelinen and published by Artech House. This book was released on 2004 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: An excellent resource for engineers and technicians alike, this practical design guide offers a comprehensive and easy-to-understand overview of the most important aspects and components of radio frequency equipment and systems. The book applies theoretical fundamentals to real-world issues, heavily relying on examples from recent design projects. Key discussions include system design schemes, circuits and components for system evaluations and design, RF measurement instrumentation, antennas and associated hardware, and guidelines for purchasing test equipment. The book also serves as a valuable on-the-job training resources for sales engineers and a graduate-level text for courses in this area.
Download or read book Radio Frequency Micromachined Switches Switching Networks and Phase Shifters written by Shiban Kishen Koul and published by CRC Press. This book was released on 2019-05-03 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio Frequency Micromachined Switches, Switching Networks, and Phase Shifters discusses radio frequency microelectromechanical systems (RF MEMS)-based control components and will be useful for researchers and R&D engineers. It offers an in-depth study, performance analysis, and extensive characterization on micromachined switches and phase shifters. The reader will learn about basic design methodology and techniques to carry out extensive measurements on MEMS switches and phase shifters which include electrical, mechanical, power handling, linearity, temperature stability, reliability, and radio frequency performance. Practical examples included in the book will help readers to build high performance systems/subsystems using micromachined circuits. Key Features Provides simple design methodology of MEMS switches and switching networks including SPST to SP16T switches Gives an in-depth performance study of micromachined phase shifters. Detailed study on reliability and power handling capability of RF MEMS switches and phase shifters presented Proposes reconfigurable micromachined phase shifters Verifies a variety of MEMS switches and phase shifters experimentally
Download or read book Mutual Coupling Between Antennas written by Trevor S. Bird and published by John Wiley & Sons. This book was released on 2021-06-28 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mutual Coupling Between Antennas A guide to mutual coupling between various types of antennas in arrays such as wires, apertures and microstrip patches or antennas co-sited on platforms Mutual Coupling Between Antennas explores the theoretical underpinnings of mutual coupling, offers an up-to-date description of the physical effects of mutual coupling for a variety of antennas, and contains techniques for analysing and assessing its effects. The book puts the topic in historical context, presents an integral equation approach, includes the current techniques, measurement methods, and discusses the most recent advances in the field. With contributions from noted experts on the topic, the book reviews practical aspects of mutual coupling and examines applications that clearly demonstrate where the performance is impacted both positively and negatively. Mutual Coupling Between Antennas contains information on how mutual coupling can be analysed with a wide range of methods from direct computer software using discrete methods, to integral equations and Greens function methods as well as approximate asymptotic methods. This important text: Provides a theoretical background for understanding mutual coupling between various types of antennas Describes the interaction that occurs between antennas, both planned and unplanned Explores a key aspect of arrays in any wireless, radar or sensing system operating at radio frequencies Offers a groundbreaking book on antenna mutual coupling Written for antenna engineers, technical specialists, researchers and students, Mutual Coupling Between Antennas is the first book to examine mutual coupling between various types of antennas including wires, horns, microstrip patches, MIMO antennas, co-sited antennas and arrays in planar or conformal configurations.
Download or read book Frequency Independent Antennas written by Victor H. Rumsey and published by Academic Press. This book was released on 2014-06-28 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: Frequency Independent Antennas provides a reasonably complete coverage of frequency independent antennas from its inception until the middle of 1965. Most of the contents have not previously been published, except in scattered journal articles, and some are original. The first six chapters are written at a fairly easy level—about the level of a beginning graduate student or the more advanced undergraduate. The last two chapters, which deal with solutions of Maxwell's equations, are at a somewhat higher level. The book opens with a discussion of some fundamental ideas about antennas. It shows how typical measurements can be understood in terms of classical electromagnetic theory: in other words, how to make sense of measured data, how to set up apparatus to get meaningful data, and how to test their significance. Separate chapters follow on the features of frequency independent, plane-sheet, spiral, and log-periodic antennas. Subsequent chapters discuss how the periodic structure theory provides a way of understanding the peculiarities of frequency independent antennas; and solutions of Maxwell's equations for idealized spiral and idealized sinusoidal structures.
Download or read book Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer. This book was released on 1976 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and dis· seminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) *at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the ac· tivity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volume were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 20 (thesis year 1975) a total of 10,374 theses titles from 28 Canadian and 239 United States universities. We are sure that this broader base for theses titles reported will greatly enhance the value of this important annual reference work. The organization of Volume 20 is identical to that of past years. It consists of theses titles arranged by discipline and by university within each discipline.
Download or read book Quantum Mechanics written by Julian Schwinger and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: A unique legacy, these lecture notes of Schwinger’s course held at the University of California at Los Angeles were carefully edited by his former collaborator Berthold-Georg Englert and constitute both a self-contained textbook on quantum mechanics and an indispensable source of reference on this fundamental subject by one of the foremost thinkers of twentieth century physics.
Download or read book Digital Techniques written by William E. Tipton and published by . This book was released on 1984 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Micro and Smart Systems written by G. K. Ananthasuresh and published by Wiley Global Education. This book was released on 2012-04-13 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microsystems are systems that integrate, on a chip or a package, one or more of many different categories of microdevices. As the past few decades were dominated by the development and rapid miniaturization of circuitry, the current and coming decades are witnessing a similar revolution in the miniaturization of sensors, actuators, and electronics; and communication, control and power devices. Applications ranging from biomedicine to warfare are driving rapid innovation and growth in the field, which is pushing this topic into graduate and undergraduate curricula in electrical, mechanical, and biomedical engineering.
Download or read book Basic Organic Stereochemistry written by Ernest L. Eliel and published by Wiley-Interscience. This book was released on 2001-04-11 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Practical Introduction to Stereochemistry Stereoisomers are compounds with the same chemical formula and connectivity but with different arrangements of their atoms in 3-dimensional space. Stereochemistry encompasses the study of stereoisomers and their properties. Despite having an identical chemical formula, stereoisomers can have drastically different biological, medicinal, and chemical properties. Basic Organic Stereochemistry explains in clear, concise terms the concepts and properties of stereoisomers. Ideal both as a text for advanced undergraduate or graduate students and as a handy guide for researchers in industry, this superb text covers: * Polarimetry and optical rotation * Internal coordinates, configuration, and conformation * Nature of stereoisomers * Barriers between stereoisomers and residual stereoisomers * Symmetry operators and symmetry point groups * Properties of stereoisomers and stereoisomer discrimination * Separation of stereoisomers, resolution, and racemization Suitable for students in organic and biological chemistry, Basic Organic Stereochemistry is unparalleled as a convenient text.
Download or read book The U S Sheep Industry written by Richard P. Stillman and published by . This book was released on 1990 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microstrip Phased array Antennas written by Adrianus Bernardus Smolders and published by . This book was released on 1994 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book RF Design Guide written by Peter Vizmuller and published by Artech House. This book was released on 1995 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gain fast access to design information required for any RF communication project using high-frequency circuits and systems with this bestseller. It contains measurement methods, system calculations, statistical procedures, and actual circuit and measurement examples that help you shorten design cycles, improve quality, and reduce design risks. Augmented with 400 equations and 210 figures, the book is an ideal reference for product designers and consultants in the RF and wireless communications industry and an outstanding learning tool for classroom use.
Download or read book 2020 43rd International Spring Seminar on Electronics Technology ISSE written by IEEE Staff and published by . This book was released on 2020-05-14 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The 43nd International Spring Seminar on Electronics Technology is a renowned European forum for the exchange of knowledge between senior and young scientists from academic communities and electronic industries from around the world on topics related to their experimental and theoretical work in the very wide spread field of electronics and micro nanoelectronics technology and in particular electronics packaging technology The motto of the upcoming conference event is Trends in Microelectronics Packaging and Interconnection Technology In the frame of a unique combination of poster exhibitions, oral paper presentations, and individual meetings senior and junior researchers from all over the world come together to discuss scientific problems and their teaching experiences as well as plan and organize international research co operations and student exchanges in a convenient and multicultural atmosphere
