Modeling a longitudinally coupled dual-mode leaky-SAW resonator filter with enhanced upper-sideband suppression

C K Campbell; P J Edmonson

doi:10.1109/58.949738

Modeling a longitudinally coupled dual-mode leaky-SAW resonator filter with enhanced upper-sideband suppression

IEEE Trans Ultrason Ferroelectr Freq Control. 2001 Sep;48(5):1298-301. doi: 10.1109/58.949738.

Authors

C K Campbell¹, P J Edmonson

Affiliation

¹ Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada. colin.kydd.campbell@sympatico.ca

PMID: 11570754
DOI: 10.1109/58.949738

Abstract

Recently, it has been experimentally reported that enhanced upper-sideband suppression of a longitudinally coupled (first/third) dual-mode leaky SAW (LSAW) resonator filter may be obtained by incorporation of a selectively valued capacitor between input and output terminals. In this paper, coupling-of-modes (COM) and bandstop-filter modeling is applied to realize this enhanced suppression. Tradeoffs are examined between upper and lower side-band suppression levels caused by the ensuing capacitive coupling between input and output terminals. Good agreement is obtained between this theory and reported experimental results for an 800-MHz band cellular filter.