Surface Acoustic Wave Filters

This book 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

Preface; Foreword; Basic Survey; Acoustic waves in elastic solids; Electrical excitation at a plane surface; Propagation effects and materials; Non-reflective transducers; Bandpass filtering using non-reflective transducers; Correlators for pulse compression radar and communications; Reflective gratings and transducers; Unidirectional transducers and their application to bandpass filtering; Waveguides and transversely-coupled resonator (TCR) filters; Resonators and resonator filters; Appendix A. Fourier transforms and linear filters; Appendix B. Reciprocity; Appendix C. Elemental charge density for regular electrodes; Appendix D. P-matrix relations; Appendix E. Electrical loading in an array of regular electrodes