Title :
SAW filters with weighted tapered interdigital transducers
Author_Institution :
Inst. of Electron. & Commun., Tech. Univ. of Poznan, Poland
Abstract :
Results of the investigations of 50% wideband surface acoustic wave (SAW) filters with 70-MHz central frequency and multichannel filters with weighted tapered interdigital transducers (TIDTs) are presented. Computer results are given for different constructions of SAW filters with TIDTs to which variable metallization ratio, apodization, capacitance, or withdrawal weighting techniques are applied. In tested filters stopband rejection from 31 to 42 dB is obtained with relative accuracy of 1 dB within passband. Frequency responses of reflected signals and SAW amplitude profiles launched by TIDTs as a function of frequency and distance are given. Computer and experimental results of a 10-channel filter are presented
Keywords :
frequency response; surface acoustic wave filters; ultrasonic transducers; 70 MHz; SAW amplitude profiles; SAW filters; TIDTs; apodization; capacitance; central frequency; frequency response; multichannel filters; reflected signals; stopband rejection; variable metallization ratio; weighted tapered interdigital transducers; withdrawal weighting techniques; Acoustic testing; Acoustic transducers; Acoustic waves; Capacitance; Frequency; Metallization; Passband; SAW filters; Surface acoustic waves; Wideband;
Conference_Titel :
Ultrasonics Symposium, 1992. Proceedings., IEEE 1992
Conference_Location :
Tucson, AZ
Print_ISBN :
0-7803-0562-0
DOI :
10.1109/ULTSYM.1992.276036
