Title :
Design and performance of wide-band IIDT-type SAW filters with low loss and improved sidelobe suppression
Author :
Weigel, R. ; Bader, B. ; Fischerauer, G. ; Russer, P.
Author_Institution :
Tech. Univ. Munchen, Germany
Abstract :
Wideband low-loss surface-acoustic-wave (SAW) filters employing interdigitated interdigital transducers (IIDTs) suitable for cellular radio systems are presented. The filters were fabricated on 36 degrees Y-X LiTaO/sub 3/ substrates. The sidelobe suppression has been improved by withdrawal weighting techniques. A design method which optimizes the weighting functions and the number of fingers has been worked out. In the 500-MHz band, fractional bandwidths of up to 5.2% with passband ripples smaller than 1 dB were attained. Insertion loss and sidelobe suppression were at 1.8 dB and 23 dB, respectively.<>
Keywords :
cellular radio; radiofrequency filters; surface acoustic wave filters; 1.8 dB; 500 MHz; IIDT-type SAW filters; LiTaO/sub 3/ substrates; cellular radio systems; design method; interdigitated interdigital transducers; low loss; sidelobe suppression; surface-acoustic-wave; weighting functions; wideband type; withdrawal weighting techniques; Bandwidth; Design methodology; Design optimization; Fingers; Land mobile radio cellular systems; Performance loss; SAW filters; Surface acoustic waves; Transducers; Wideband;
Conference_Titel :
Microwave Symposium Digest, 1993., IEEE MTT-S International
Conference_Location :
Atlanta, GA, USA
Print_ISBN :
0-7803-1209-0
DOI :
10.1109/MWSYM.1993.276855
