An equation is derived for the transverse-mode frequencies of a two-port surface-acoustic-wave (SAW) resonator with uniform reflection gratings. It is postulated that only odd-order (symmetric) transverse modes should be excited in such a grating, due to its symmetrical placement with respect to the interdigital transducer (IDT). Frequency response modeling involves a summation of one-dimensional transmission-matrix computations for the fundamental mode and participating transverse ones. Excellent agreement is obtained between theory and experiment for a 360-MHz resonator with three close-in transverse modes, attributed to symmetric modes of odd order m=3, 5, 7.<
Published in:
Ultrasonics, Ferroelectrics and Frequency Control, IEEE Transactions on
(Volume:38
,
Issue:
3
)
Date of Publication: May 1991