Recent Developments in Surface Acoustic Waves


Book Description

The topic of surface waves lies at the interface between a number of disci plines - physics, theoretical and applied mechanics, electroacoustics, ap plied mathematics, surface science and seismology. This volume, based on papers delivered at European Mechanics Colloquium 226, reflects this diversity in approach and background, while showing strong links between phenomena arising from different fields. The emphasis is on recent de velopments such as nonlinear and other nonclassical effects,which have great importance for both pure science and for applications such as signal processing, nondestructive evaluation and seismic studies. In recent years there has been considerable progress in the mathe matical treatment of nonlinear effects, of viscoelastic and of more novel constitutive effects which modify the predictions of linear elastic and piezo electric theory for surface acoustic wave (SAW) propagation. A number of these themes serve to group the contents of this volume. Part I contains recent advances in the rigorous mathematical treatment of nonlinearity, together with a paper giving experimental results showing the need for further theoretical development. Part II deals with anisotropic elasticity, showing that even the linear theory presents many possible behaviours, which are still not fully categorized.




Surface Acoustic Wave Devices and Their Signal Processing Applications


Book Description

Surface Acoustic Wave Devices and Their Signal Processing Applications is a textbook that combines experiment and theory in assessing the signal processing applications of surface acoustic wave (SAW) devices. The operating principles of SAW devices are described from a circuit design viewpoint. This book is comprised of 18 chapters and begins with a historical background on surface acoustic waves and a discussion on the merits of SAW devices as well as their applications. The next chapter introduces the reader to the basics of acoustic waves and piezoelectricity, together with the effect of acoustic bulk waves on the performance of SAW filters. The principles of linear phase SAW filter design and equivalent circuit models for a SAW filter are then described. The remaining chapters focus on trade-offs in linear phase SAW filter design; compensation for second-order effects; harmonic SAW delay lines for gigahertz frequencies; and coding techniques using linear SAW transducers. The final chapter highlights Some other significant alternative design techniques and applications for SAW devices. This monograph will be suitable for engineering or physics students as well as engineers, scientists, and technical staff in industry who seek further information on SAW-based circuits, systems, and applications.




Surface Acoustic Wave Devices in Telecommunications


Book Description

Surface acoustic wave (SAW) devices are widely used in mobile communications, a rapidly evolving market. This book gives an overview on the latest SAW technologies with an emphasis on the design and simulation of devices, such as resonator-based devices employing the SH-type leaky SAW.




Advances in Surface Acoustic Wave Technology, Systems and Applications


Book Description

Surface acoustic wave (SAW) devices are recognized for their versatility and efficiency in controlling and processing electrical signals. This has resulted in a multitude of device concepts for a wide range of signal processing functions, such as delay lines, filters, resonators, pulse compressors, convolvers, and many more. As SAW technology has found its way into mass market products such as TV receivers, pagers, keyless entry systems and cellular phones, the production volume has risen to millions of devices produced every day. At the other end of the scale, these are specialized high performance signal processing SAW devices for satellite communication and military applications, such as radar and electronic warfare. This volume, together with Volume 1, presents an overview of recent advances in SAW technology, systems and applications by some of the foremost researchers in this exciting field. Contents: Coupling-of-Modes Analysis of SAW Devices (V Plessky & J Koskela); Theory and Applications of Green''s Functions (A R Baghai-Wadji); New Piezoelectric Substrates for SAW Devices (J Kosinski); Pseudo and High Velocity Pseudo SAWs (M P da Cunha); SAW Devices Beyond 5 GHz (H Odagawa & K Yamanouchi); Wireless SAW Identification and Sensor Systems (F Schmidt & G Scholl); Interaction of Surface Acoustic Waves, Electrons, and Light (A Wixforth). Readership: Graduate students, researchers and academics in device and circuit design, as well as designers of mobile communications systems.




Microscale Acoustofluidics


Book Description

The manipulation of cells and microparticles within microfluidic systems using external forces is valuable for many microscale analytical and bioanalytical applications. Acoustofluidics is the ultrasound-based external forcing of microparticles with microfluidic systems. It has gained much interest because it allows for the simple label-free separation of microparticles based on their mechanical properties without affecting the microparticles themselves. Microscale Acoustofluidics provides an introduction to the field providing the background to the fundamental physics including chapters on governing equations in microfluidics and perturbation theory and ultrasound resonances, acoustic radiation force on small particles, continuum mechanics for ultrasonic particle manipulation, and piezoelectricity and application to the excitation of acoustic fields for ultrasonic particle manipulation. The book also provides information on the design and characterization of ultrasonic particle manipulation devices as well as applications in acoustic trapping and immunoassays. Written by leading experts in the field, the book will appeal to postgraduate students and researchers interested in microfluidics and lab-on-a-chip applications.




Surface Acoustic Wave Filters


Book Description

Surface Acoustic Wave Filters gives the fundamental principles and device design techniques for surface acoustic wave filters. It covers the devices in widespread use today: bandpass and pulse compression filters, correlators and non-linear convolvers and resonators. The newest technologies for low bandpass filters are fully covered such as unidirectional transducers, resonators in impedance element filters, resonators in double-mode surface acoustic wave filters and transverse-coupled resonators using waveguides. The book covers the theory of acoustic wave physics, the piezoelectric effect, electrostatics at a surface, effective permittivity, piezoelectric SAW excitation and reception, and the SAW element factor. These are the main requirements for developing quasi-static theory, which gives a basis for the non-reflective transducers in transversal bandpass filters and interdigital pulse compression filters. It is also needed for the reflective transducers used in the newer devices. A thorough revision of a classic on surface acoustic wave filters first published in 1985 and still in print Uniquely combines easy-to-understand principles with practical design techniques for all the devices in widespread use today Complete coverage of all the latest devices which are key to mobile phones, TVs and radar systems Includes a new foreword by Sir Eric Albert Ash




Acoustic Wave Sensors


Book Description

Written by an interdisciplinary group of experts from both industry and academia, Acoustic Wave Sensors provides an in-depth look at the current state of acoustic wave devices and the scope of their use in chemical, biochemical, and physical measurements, as well as in engineering applications. Because of the inherent interdisciplinary applications of these devices, this book will be useful for the chemist and biochemist interested in the use and development ofthese sensors for specific applications; the electrical engineer involved in the design and improvement of these devices; the chemical engineer and the biotechnologist interested in using these devices for process monitoring and control; and the sensor community at large. - Provides in-depth comparison and analyses of different types of acoustic wave devices - Discusses operating principles and design considerations - Includes table of relevant material constants for quick reference - Presents an extensive review of current uses of these devices for chemical, biochemical, and physical measurements, and engineering applications




Surface Acoustic Waves in Inhomogeneous Media


Book Description

Surface Acoustic Waves in Inhomogeneous Media covers almost all important problems of the interaction of different types of surface acoustic waves with surface inhomogeneities. The problems of surface acoustic wave interaction with periodic topographic gratings widely used in filters and resonators are under careful consideration. The most important results of surface wave scattering by local defects such as grooves, random roughness, elastic wedges are given. Different theoretical approaches and practical rules for solving the surface wave problems are presented.




Modeling and Measurement Methods for Acoustic Waves and for Acoustic Microdevices


Book Description

Acoustics is a mature field which enjoys a never ending youth. New developments are induced by either the search for a better understanding, or by technological innovations. Micro-fabrication techniques introduced a whole new class of microdevices, which exploit acoustic waves for various tasks, and in particular for information processing and for sensing purposes. Performance improvements are achievable by better modelling tools, able to deal with more complex configurations, and by more refined techniques of fabrication and of integration in technological systems, like wireless communications. Several chapters of this book deal with modelling and fabrication techniques for microdevices, including unconventional phenomena and configurations. But this is far from exhausting the research lines in acoustics. Theoretical analyses and modelling techniques are presented, for phenomena ranging from the detection of cracks to the acoustics of the oceans. Measurement methods are also discussed, which probe by acoustic waves the properties of widely different systems.




Gas Sensors


Book Description

There were two reasons that induced me to plan and to organize this book, the first was the lack of a text entirely devoted to the subject of gas sensors, notwithstanding some books devoted to the various kind of chemical sensors have recently been published. The second reason was the need of introducing the basic topics of gas detection mechanisms to a growing number of researchers active in research and development laboratories of industries and uni versities. The field of chemical sensors is indeed in fast and consistent growth, as it is proved by the increased number of participants to the congresses that were recently held on this subject, namely the Third Meeting on Chemical Sensors (September 24 - 26, 1990, Cleveland), Transducers' 91 (June 24 - 27, 1991, S. Francisco) and EUROSENSORS V (September 30 - October 3, 1991, Rome). Therefore, this book is mainly intended as a reference text for researchers with a MS degree in physics, chemistry and electrical engineering; it reports the last progresses in the R. & D. and in the technology of gas sensors. I choose to deal specifically with the topic of gas sensors because these devices show a very large number of applications in the domestic and industrial field and they are characterized by a great effort of research and development.