Design of low-shape-factor SAW filters having a single acoustic track

Author

Bausk, Evgeniy V. ; Yakovkin, Igor B.

Author_Institution

Inst. of Semicond. Phys., Acad. of Sci., Novosibirsk, Russia

fYear

1996

fDate

5-7 Jun 1996

Firstpage

291

Lastpage

295

Abstract

The problem discussed here is a realization of frequency responses both with a shape factor of 1.3 or less and with a stopband rejection of 40 dB or more for the most simple and compact configuration of surface acoustic wave (SAW) filters. This SAW filter modification has one acoustic track and only two selective elements: an input apodized interdigital transducer (IDT) and an output withdrawal weighted one. The majority of known algorithms for optimization of withdrawal weighted (WW) IDTs are effective for transducers with a large number of electrodes and band width of 1% or less. An algorithm proposed here is intended for optimization of broadband WW transducers. Experimental characteristics of designed filters are: a bandwidth of 5-9%, a stopband rejection of 115-55 dB, a 3 dB-10 dB shape factor of 1.07-1.3

Keywords

interdigital transducers; optimisation; surface acoustic wave filters; surface acoustic wave transducers; SAW filter; apodized interdigital transducer; broadband WW transducer; design; frequency response; optimization algorithm; shape factor; single acoustic track; stopband rejection; surface acoustic wave filter; withdrawal weighted IDT; Acoustic transducers; Acoustic waves; Bandwidth; Electrodes; Frequency response; Passband; Piezoelectric transducers; SAW filters; Shape; Surface acoustic waves;

fLanguage

English

Publisher

ieee

Conference_Titel

Frequency Control Symposium, 1996. 50th., Proceedings of the 1996 IEEE International.

Conference_Location

Honolulu, HI

Print_ISBN

0-7803-3309-8

Type

conf

DOI

10.1109/FREQ.1996.559869

Filename

559869