Frequency-Agile Antennas for Wireless Communications


Book Description

Mobile data subscriptions are expected to more than double and mobile wireless traffic to increase by more than tenfold over the next few years. Proliferation of smart phones, tablets, and other portable devices are placing greater demands for services such as web browsing, global positioning, video streaming, and video telephony. Many of the proposed solutions to deal with these demands will have a significant impact on antenna designs. Antennas with frequency agility are considered a promising technology to help implement these new solutions. This book provides readers with a sense of the capabilities of frequency-agile antennas (FAAs), the widely diverse methods for achieving tunability, the current achievable performance, and the challenges still facing FAA designs. This resource explores the many aspects of FAAs, including an examination of the metrics used to evaluate their performance, a review of the most commonly used antenna elements, an in-depth look at the wide variety of mechanisms for achieving tunability, and a comprehensive survey of diverse examples of FAA designs. The focus is on FAAs for wireless mobile communications with applications including handsets, laptops, wireless machine-to-machine communications, as well as larger, fixed designs such as cellular base station antennas.




Materials Issues for Tunable RF and Microwave Devices III: Volume 720


Book Description

Challenges facing the implementation of an affordable tunable RF and microwave device technology are discussed in these papers from an April 2002 meeting. Materials issues and devices are examined, with information on new tunable materials, issues of preparation and optimization of bulk and think film properties, material and surface characterization, evaluation of material loss and loss mechanisms, and effects of microstructure. At the device level, phase shifters are discussed and a new device concept for variable true time delay versus phase shift is introduced. At the system level, a paraelectric lens is used to demonstrate electronic beam steering of an antenna. Tidrow is affiliated with the US Army Research Laboratory. Annotation copyrighted by Book News, Inc., Portland, OR




Ferroelectrics in Microwave Devices, Circuits and Systems


Book Description

Today’s wireless communications and information systems are heavily based on microwave technology. Current trends indicate that in the future along with - crowaves, the millimeter wave and Terahertz technologies will be used to meet the growing bandwidth and overall performance requirements. Moreover, motivated by the needs of the society, new industry sectors are gaining ground; such as wi- less sensor networks, safety and security systems, automotive, medical, envir- mental/food monitoring, radio tags etc. Furthermore, the progress and the pr- lems in the modern society indicate that in the future these systems have to be more user/consumer friendly, i. e. adaptable, reconfigurable and cost effective. The mobile phone is a typical example which today is much more than just a phone; it includes a range of new functionalities such as Internet, GPS, TV, etc. To handle, in a cost effective way, all available and new future standards, the growing n- ber of the channels and bandwidth both the mobile handsets and the associated systems have to be agile (adaptable/reconfigurable). The complex societal needs have initiated considerable activities in the field of cognitive and software defined radios and triggered extensive research in adequate components and technology platforms. To meet the stringent requirements of these systems, especially in ag- ity and cost, new components with enhanced performances and new functionalities are needed. In this sense the components based on ferroelectrics have greater - tential and already are gaining ground.




JJAP


Book Description




Advances in Dielectric Materials and Electronic Devices


Book Description

This proceedings contains papers presented at the Advanced Dielectric Materials: Design, Preparation, Processing and Applications; and Advanced Dielectrics for Wireless Communications symposia. Topics include design of material, materials synthesis and processing, processing-microstructure-property relationship, multilayer device materials, thin and thick films, device applications, low temperature co-fired ceramics (LTCC)for multilayer devices, microwave dielectric materials and much more.




Microstrip Filters for RF / Microwave Applications


Book Description

The first edition of “Microstrip Filters for RF/Microwave Applications” was published in 2001. Over the years the book has been well received and is used extensively in both academia and industry by microwave researchers and engineers. From its inception as a manuscript the book is almost 8 years old. While the fundamentals of filter circuits have not changed, further innovations in filter realizations and other applications have occurred with changes in the technology and use of new fabrication processes, such as the recent advances in RF MEMS and ferroelectric films for tunable filters; the use of liquid crystal polymer (LCP) substrates for multilayer circuits, as well as the new filters for dual-band, multi-band and ultra wideband (UWB) applications. Although the microstrip filter remains as the main transmission line medium for these new developments, there has been a new trend of using combined planar transmission line structures such as co-planar waveguide (CPW) and slotted ground structures for novel physical implementations beyond the single layer in order to achieve filter miniaturization and better performance. Also, over the years, practitioners have suggested topics that should be added for completeness, or deleted in some cases, as they were not very useful in practice. In view of the above, the authors are proposing a revised version of the “Microstrip Filters for RF/Microwave Applications” text and a slightly changed book title of “Planar Filters for RF/Microwave Applications” to reflect the aforementioned trends in the revised book.




Ferroelectrics


Book Description

Combining both fundamental principles and real-life applications in a single volume, this book discusses the latest research results in ferroelectrics, including many new ferroelectric materials for the latest technologies, such as capacitors, transducers and memories. The first two chapters introduce dielectrics and microscopic materials properties, while the following chapter discusses pyroelectricity and piezoelectricity. The larger part of the text is devoted to ferroelectricity and ferroelectric ceramics, with not only their fundamentals but also applications discussed. The book concludes with a look at the future for laser printed materials and applications. With over 600 references to recent publications on piezoelectric and ferroelectric materials, this is an invaluable reference for physicists, materials scientists and engineers.




Microstrip Filters for RF / Microwave Applications


Book Description

Advanced, specialized coverage of microstrip filter design Microstrip Filters for RF/Microwave Applications is the only professional reference focusing solely on microstrip filters. It offers a unique and comprehensive treatment of filters based on the microstrip structure and includes full design methodologies that are also applicable to waveguide and other transmission line filters. The authors include coverage of new configurations with advanced filtering characteristics, new design techniques, and methods for filter miniaturization. The book utilizes numerous design examples to illustrate and emphasize computer analysis and synthesis while also discussing the applications of commercially available software. Other highlights include: Lowpass and bandpass filters Highpass and bandstop filters Full-wave electromagnetic simulation Advanced materials and technologies Coupled resonator circuits Computer-aided design for low-cost/high-volume production Compact filters and filter miniaturization Microstrip Filters for RF/Microwave Applications is not only a valuable design resource for practitioners, but also a handy reference for students and researchers in microwave engineering.




Global Roadmap for Ceramic and Glass Technology


Book Description

This is the only global roadmap that identifies the technical and manufacturing challenges associated with the development and expansion of commercial markets for ceramics and glass. Featuring presentations by industry leaders at the 1st International Congress on Ceramics (ICC) held in 2006, it suggests positive, proactive ways to address these challenges. The ICC Global Roadmap contains the following content: 1) Summary papers prepared by the invited speakers before the meeting 2) A detailed account of the presentation of each invited speaker written by an editor who attends the presentation 3) A summary account and future recommendations for the industry on each topic covered written by the board and the president of this meeting, Dr. Stephen Freiman (National Institutes of Standards and Technology) 4) The CDRom accompanying the book contains all of the above as well as pdfs of the presentations for non-invited speakers, including posters presented and discussed.