Low-loss SAW filters using new SPUDT structures

Author

Chvets, V.B. ; Ivanov, P.G. ; Makarov, V.M. ; Orlov, V.S.

Author_Institution

Radiocommun. Res. Inst., Moscow, Russia

Volume

1

fYear

1997

fDate

5-8 Oct 1997

Firstpage

69

Abstract

The new SPUDT structures based on triple electrode sections (TES) per wavelength with the period between SAW sources about nλ/3 are presented. The simulation technique which accounts for second order effects has been developed within the framework of modified equivalent circuit model. The SPUDT structures have been implemented in filters with 0.1-3.2% bandwidths fabricated on quartz and LiTaO₃ substrates. The results of simulation have been verified experimentally and show that insertion loss of TES SPUDT filters is less by 1.0-1.5 dB than that in conventional SPUDT filters. The impedance frequency dependence becomes more symmetrical and the passband distortions are reduced. Stopband rejection is 50-60 dB

Keywords

acoustic impedance; equivalent circuits; lithium compounds; losses; quartz; surface acoustic wave filters; surface acoustic wave resonator filters; surface acoustic wave transducers; LiTaO₃; SPUDT structures; SiO₂; TES SPUDT filters; bandwidths; impedance frequency dependence; insertion loss; low-loss SAW filters; modified equivalent circuit model; passband distortions; quartz; second order effects; simulation technique; stopband rejection; triple electrode sections; Band pass filters; Bandwidth; Circuit simulation; Electrodes; Equivalent circuits; Frequency dependence; Impedance; Insertion loss; SAW filters; Surface acoustic waves;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 1997. Proceedings., 1997 IEEE

Conference_Location

Toronto, Ont.

ISSN

1051-0117

Print_ISBN

0-7803-4153-8

Type

conf

DOI

10.1109/ULTSYM.1997.662982

Filename

662982