Calculation of Interdigital Transducer Interaction with SAWs and BAWs

  • F. Seifert
  • A. R. Baghai-Wadji
  • K. C. Wagner
  • G. Kovacs
Part of the Springer Series on Wave Phenomena book series (SSWAV, volume 7)


Since the interdigital transducer (IDT) was used by WHITE and VOLTMER /1/ in 1965 to excite surface acoustic waves (SAWs) on plane piezoelectric substrates, signal processing devices based on this effect have evolved to a high degree of maturity and are described comprehensively in the book by MORGAN /2/. These devices are fabricated in a one step planar metal layer technology and consist mainly of launching (L) and receiving (R) — IDTs whose structure determines the electric filter characteristic. Simple physical reasoning shows, that the IDT’s SAW impulse response h(t) in a first approximation is given by its structure (i.e. the finger arrangement and mutual finger overlap, called apodisation). Fourier transform (FT ) yields the transfer function \(\bar H\)(w) of the IDT:
$$\bar H\left( w \right) = F{T^ - }\left( {h\left( t \right)} \right).$$


Charge Distribution Effective Permittivity Bulk Wave Line Charge Wavenumber Domain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • F. Seifert
    • 1
  • A. R. Baghai-Wadji
    • 1
  • K. C. Wagner
    • 1
  • G. Kovacs
    • 1
  1. 1.IAEETechnical UniversityWienAustria

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