Title :
S.A.W. bandpass filter with ¿50 dB sidelobes using unweighted i.d.t.s
Author :
Sudhakar, P. ; Bhattacharyya, A.B. ; Mathur, Bimal
Author_Institution :
Indian Institute of Technology, Centre for Applied Research in Electronics, Department of Electrical Engineering, New Delhi, India
Abstract :
The use of a resonantly loaded i.d.t. (r.l.i.d.t.) as an s.a.w. track changer in bandpass filter design is described. A filter with 3dB fractional bandwidth (f.b.w.) of 11.5% and ¿50 dB sidelobes is realised using unweighted input/output i.d.t.s of 5¿ finger pairs each and a 7¿ finger pair r.l.i.d.t. as the s.a.w. track changer. The scheme is expected to be useful in realising low-shape-factor low-sidelobe bandpass filters using relatively short i.d.t.s.
Keywords :
band-pass filters; surface acoustic wave devices; -50 dB sidelobes; 3 dB fractional bandwidth; SAW bandpass filter; resonantly loaded interdigital transducer; surface acoustic wave; unweighted IDT;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19780293
