Title :
Analysis of SAW grating waveguides using 2-D coupling-of-modes equations
Author :
Hirota, Kazuhiro ; Nakamura, Kiyoshi
Author_Institution :
Toyo Commun. Equip. Co. Ltd., Kanagawa, Japan
Abstract :
In surface acoustic wave (SAW) periodic structures, the phase velocity in the grating region has a velocity dispersion caused by the periodic perturbation. Therefore, a grating waveguide with a finite width needs to be analyzed considering the frequency dependence. In this paper, the paraxial two-dimensional coupling-of-modes equations (2-D COM equations) presented by Haus and Wang (1978) are extended to take into account substrate anisotropy, propagation loss, and electrical terminals. A distributed-parameter equivalent circuit for each guided mode is derived from the solution of the 2-D COM equations and some electrical transmission responses calculated using this circuit are compared with measured results
Keywords :
coupled mode analysis; equivalent circuits; interdigital transducers; losses; periodic structures; surface acoustic wave waveguides; 2D coupling-of-modes equations; SAW grating waveguides; SAW periodic structures; distributed parameter equivalent circuit; electrical terminals; electrical transmission responses; finite width; frequency dependence; paraxial two-dimensional COM equations; periodic perturbation; phase velocity; propagation loss; substrate anisotropy; surface acoustic wave periodic structures; velocity dispersion; Acoustic waveguides; Acoustic waves; Anisotropic magnetoresistance; Coupling circuits; Equations; Frequency dependence; Gratings; Periodic structures; Surface acoustic waves; Two dimensional displays;
Conference_Titel :
Ultrasonics Symposium, 2001 IEEE
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-7177-1
DOI :
10.1109/ULTSYM.2001.991591
