Reconfigurable Low Profile Antennas Using Tunable High Impedance Surfaces

Reconfigurable Low Profile Antennas Using Tunable High Impedance Surfaces PDF Author: David Cure
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
This dissertation shows a detailed investigation on reconfigurable low profile antennas using tunable high impedance surfaces (HIS). The specific class of HIS used in this dissertation is called a frequency selective surface (FSS). This type of periodic structure is fabricated to create artificial magnetic conductors (AMCs) that exhibit properties similar to perfect magnetic conductors (PMCs). The antennas are intended for radiometric sensing applications in the biomedical field. For the particular sensing application of interest in this dissertation, the performance of the antenna sub-system is the most critical aspect of the radiometer design where characteristics such as small size, light weight, conformability, simple integration, adjustment in response to adverse environmental loading, and the ability to block external radio frequency interference to maximize the detection sensitivity are desirable. The antenna designs in this dissertation are based on broadband dipole antennas over a tunable FSS to extend the usable frequency range. The main features of these antennas are the use of an FSS that does not include via connections to ground, their low profile and potentially conformal nature, high front-to-back radiation pattern ratio, and the ability to dynamically adjust the center frequency. The reduction of interlayer wiring on the tunable FSS minimizes the fabrication complexity and facilitates the use of flexible substrates. This dissertation aims to advance the state of the art in low profile tunable planar antennas. It shows a qualitative comparison between antennas backed with different unit cell geometries. It demonstrates the feasibility to use either semiconductor or ferroelectric thin film varactor-based tunable FSS to allow adjustment in the antenna frequency in response to environment loading in the near-field.

Reconfigurable Low Profile Antennas Using Tunable High Impedance Surfaces

Reconfigurable Low Profile Antennas Using Tunable High Impedance Surfaces PDF Author: David Cure
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
This dissertation shows a detailed investigation on reconfigurable low profile antennas using tunable high impedance surfaces (HIS). The specific class of HIS used in this dissertation is called a frequency selective surface (FSS). This type of periodic structure is fabricated to create artificial magnetic conductors (AMCs) that exhibit properties similar to perfect magnetic conductors (PMCs). The antennas are intended for radiometric sensing applications in the biomedical field. For the particular sensing application of interest in this dissertation, the performance of the antenna sub-system is the most critical aspect of the radiometer design where characteristics such as small size, light weight, conformability, simple integration, adjustment in response to adverse environmental loading, and the ability to block external radio frequency interference to maximize the detection sensitivity are desirable. The antenna designs in this dissertation are based on broadband dipole antennas over a tunable FSS to extend the usable frequency range. The main features of these antennas are the use of an FSS that does not include via connections to ground, their low profile and potentially conformal nature, high front-to-back radiation pattern ratio, and the ability to dynamically adjust the center frequency. The reduction of interlayer wiring on the tunable FSS minimizes the fabrication complexity and facilitates the use of flexible substrates. This dissertation aims to advance the state of the art in low profile tunable planar antennas. It shows a qualitative comparison between antennas backed with different unit cell geometries. It demonstrates the feasibility to use either semiconductor or ferroelectric thin film varactor-based tunable FSS to allow adjustment in the antenna frequency in response to environment loading in the near-field.

Tunable and Reconfigurable Optical Metamaterials

Tunable and Reconfigurable Optical Metamaterials PDF Author: Yuancheng Fan
Publisher: Frontiers Media SA
ISBN: 2889635082
Category : Science
Languages : en
Pages : 84

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Book Description


Tunable Antennas and Microwave Circuits for Next Generation Reconfigurable Front Ends

Tunable Antennas and Microwave Circuits for Next Generation Reconfigurable Front Ends PDF Author: Javier Rodriguez De Luis
Publisher:
ISBN: 9781124668406
Category :
Languages : en
Pages : 181

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Book Description
Reconfigurable antennas and microwave circuits have attracted much attention in recent years due to their advantages compared to conventional designs. It is recognized that systems exploiting a certain extent of tunability potentially benefit from multi-functionality and performance enhancement, which ultimately translates into lower component count, size and overall cost of the transceiver. In this work, a collection of tunable/reconfigurable designs comprising of antennas and passive microwave circuits that spans to different application areas is presented in a comprehensive manner. In chapter 2 a dual frequency reconfigurable antenna array using PIN diodes and its associated phase shifter are presented. The system is capable of operation at two independent frequencies (4.7GHz and 7.5GHz) while switching between four different radiation patterns types for each frequency. Chapter 3 explores the feasibility of a novel of iso-frequency repeater system based on reconfigurable parasitic elements to maximize the isolation between the transmitting and receiving antennas. In chapter 4, an analytical tuning algorithm for a reconfigurable impedance matching pi-network based on tunable capacitors is presented. The algorithm is able to determine all tunable network component values for matching any given load impedance. A single pole single zero notch filter using RF MEMS tunable capacitors and its associated frequency control loop system for automatic frequency tracking are presented in chapter 5. The high Q value of the tunable capacitors enables this filter to achieve 22dB rejection with less than 0.8dB insertion loss over a 5MHz bandwidth in the International Mobile Telecommunications band (IMT, 2.1 GHz). In chapter 6, a set of approximate closed form expressions for the input impedance, resonant frequency, radiation efficiency, quality factor and impedance bandwidth of capacitively-tunable loaded planar inverted-F antennas (PIFAs) used for cell phone applications are presented. Finally, chapter 7 presents a tunable antenna pair for wireless transceivers using RF MEMS tunable capacitors. This design utilizes antenna frequency agility to cover a frequency tuning range from 1850MHz to 2170MHz (16%) corresponding to the cellular wireless bands IMT-I and PCS and is designed to provide built-in filtering between antennas.

Printed Resonant Periodic Structures and Their Applications

Printed Resonant Periodic Structures and Their Applications PDF Author: Mahesh Abegaonkar
Publisher: CRC Press
ISBN: 1498782124
Category : Science
Languages : en
Pages : 158

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Book Description
This book is a reference for researchers who want to learn about resonant periodic structures for applications in microstrip circuits. The readers can learn simple methods to analyze these structures using commercially available software and equivalent circuit modelling. The application examples demonstrated in the book will open up new research ideas in this field.

Reconfigurable Antennas

Reconfigurable Antennas PDF Author: Jennifer T. Bernhard
Publisher: Morgan & Claypool Publishers
ISBN: 1598290274
Category : Technology & Engineering
Languages : en
Pages : 74

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Book Description
This lecture explores the emerging area of reconfigurable antennas from basic concepts that provide insight into fundamental design approaches to advanced techniques and examples that offer important new capabilities for next-generation applications. Antennas are necessary and critical components of communication and radar systems, but sometimes their inability to adjust to new operating scenarios can limit system performance. Making antennas reconfigurable so that their behavior can adapt with changing system requirements or environmental conditions can ameliorate or eliminate these restrictions and provide additional levels of functionality for any system. For example, reconfigurable antennas on portable wireless devices can help to improve a noisy connection or redirect transmitted power to conserve battery life. In large phased arrays, reconfigurable antennas could be used to provide additional capabilities that may result in wider instantaneous frequency bandwidths, more extensive scan volumes, and radiation patterns with more desirable side lobe distributions. Written for individuals with a range of experience, from those with only limited prior knowledge of antennas to those working in the field today, this lecture provides both theoretical foundations and practical considerations for those who want to learn more about this exciting subject. Contents: Introduction / Definitions of Critical Parameters for Antenna Operation / Linkage Between Frequency Response and Radiation Characteristics: Implications for Reconfigurable Antennas / Methods for Achieving Frequency Response Reconfigurability / Methods for Achieving Polarization Reconfigurability / Methods for Achieving Radiation Pattern Reconfigurability / Methods for Achieving Compound Reconfigurable Antennas / Practical Issues for Implementing Reconfigurable Antennas / Conclusions and Directions for Future work

Antennas in Reconfigurable High-impedance Electromagnentic Surfaces

Antennas in Reconfigurable High-impedance Electromagnentic Surfaces PDF Author:
Publisher:
ISBN:
Category : Antennas, Dipole
Languages : en
Pages : 126

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Book Description


Reconfigurable Antennas

Reconfigurable Antennas PDF Author: Jennifer T. Bernhard
Publisher: Morgan & Claypool Publishers
ISBN: 1598290266
Category : Technology & Engineering
Languages : en
Pages : 75

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Book Description
Antennas are necessary and critical components of communication and radar systems. Making antennas reconfigurable so that their behavior can adapt with changing system requirements or environmental conditions can ameliorate or eliminate these restrictions and promises to provide additional levels of functionality for any system. If a single reconfigurable antenna could deliver the same functionality of more than one traditional single-purpose system, significant savings in cost, weight, volume, and maintenance/repair resources may be realizable.Reconfigurable Antennas describes in detail the critical parameters for antenna operation, as well as possible methods for achieving reconfigurability in each of these parameters. It also discusses practical issues surrounding the implementation of reconfigurable antennas, including feed methods, bias line design and implementation, and component selection. Finally, the book offers a view of the future of reconfigurable antennas and their promise to expand and improve system functionality in a range of different operating scenarios.

Antenna Engineering Handbook

Antenna Engineering Handbook PDF Author: John Volakis
Publisher: McGraw Hill Professional
ISBN: 1259644707
Category : Technology & Engineering
Languages : en
Pages : 1424

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Book Description
The gold-standard reference on the design and application of classic and modern antennas—fully updated to reflect the latest advances and technologiesThis new edition of the “bible of antenna engineering” has been updated to provide start-to-finish coverage of the latest innovations in antenna design and application. You will find in-depth discussion of antennas used in modern communication systems, mobile and personal wireless technologies, satellites, radar deployments, flexible electronics, and other emerging technologies, including 5G, terahertz, and wearable electronics. Antenna Engineering Handbook, Fifth Edition, is bolstered by real-world examples, hundreds of illustrations, and an emphasis on the practical aspects of antennas.Featuring 60 chapters and contributions from more than 80 renowned experts, this acclaimed resource is edited by one of the world’s leading antenna authorities. This edition features all of the classic antenna types, plus new and emerging designs, with 13 all-new chapters and important updates to nearly all chapters from past editions.Antenna Engineering Handbook, Fifth Edition, clearly explains cutting-edge applications in WLANs, automotive systems, PDAs, and handheld devices, making it an indispensable companion for today’s antenna practitioners and developers.Coverage includes:•Antenna basics and classic antennas•Design approaches for antennas and arrays•Wideband and multiband antennas•Antennas for mobile devices and PDAs, automotive applications, and aircraft•Base station and smart antennas•Beamforming and 5G antennas•Millimeter-wave and terahertz antennas•Flexible, wearable, thin film, origami, dielectric, and on-chip antennas•MIMO antennas and phased arrays•Direction-finding and GPS antennas•Active antennas•Low-profile wideband antennas•Nanoantennas•Reflectors and other satellite and radio-telescope antennas•Low-frequency, HF, VHF, UHF, ECM, and ESM antennas•Impedance-matching techniques and material characteristics•Metastructured and frequency selective surfaces•Propagation and guided structures•Computational techniques and toolsets•Indoor and outdoor measurements

Multifunctional Antennas and Arrays for Wireless Communication Systems

Multifunctional Antennas and Arrays for Wireless Communication Systems PDF Author: Satish K. Sharma
Publisher: John Wiley & Sons
ISBN: 1119535050
Category : Technology & Engineering
Languages : en
Pages : 466

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Book Description
MULTIFUNCTIONAL ANTENNAS AND ARRAYS FOR WIRELESS COMMUNICATION SYSTEMS Offers an up-to-date discussion of multifunctional antennas and arrays for wireless communication systems Multifunctional Antennas and Arrays for Wireless Communication Systems is a comprehensive reference on state-of-the-art reconfigurable antennas and 4G/5G communication antennas. The book gives a unique perspective while giving a comprehensive overview of the following topics: Frequency reconfigurable antennas Pattern reconfigurable antennas Polarization reconfigurable antennas Reconfigurable antennas using Liquid Metal, Piezoelectric, and RF MEMS MIMO and 4G/5G wireless communication antennas Metamaterials and metasurfaces in reconfigurable antennas Multifunctional antennas for user equipments (UEs) Defense related antennas and applications Flat panel phased array antennas The book is a valuable resource for the practicing engineer as well as for those within the research field. As wireless communications continuously evolves, more and more functionally will be required, and thus multifunctional antennas and RF systems will be necessary. These multifunctional antennas will require a degree of reconfigurability, and this book discusses various methods which enable this. The main topics of frequency, pattern, and polarization reconfigurability is first discussed. Methods utilizing unique materials and devices, both real and artificial are discussed. The book also delves into 4G/5G antennas as it relates to MIMO, and millimeter-wave phased arrays. Finally, there is a section on defense related multifunctional RF antenna systems.

Compact Slot Array Antennas for Wireless Communications

Compact Slot Array Antennas for Wireless Communications PDF Author: Alan J. Sangster
Publisher: Springer
ISBN: 3030017532
Category : Technology & Engineering
Languages : en
Pages : 372

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Book Description
This book describes and provides design guidelines for antennas that achieve compactness by using the slot radiator as the fundamental building block within a periodic array, rather than a phased array. It provides the basic electromagnetic tools required to design and analyse these novel antennas, with sample calculations where relevant. The book presents a focused introduction and valuable insights into the relevant antenna technology, together with an overview of the main directions in the evolving technology of compact planar arrays. While the book discusses the historical evolution of compact array antennas, its main focus is on summarising the extensive body of literature on compact antennas. With regard to the now ubiquitous slot radiator, it seeks to demonstrate how, despite significant antenna size reductions that at times even seem to defy the laws of physics, desirable radiation pattern properties can be preserved. This is supported by an examination of recent advances in frequency selective surfaces and in metamaterials, which can, if handled correctly, be used to facilitate physics-defying designs. The book offers a valuable source of information for communication systems and antenna design engineers, especially thanks to its overview of trends in compact planar arrays, yet will also be of interest to students and researchers, as it provides a focused introduction and insights into this highly relevant antenna technology.