Title :
A multi-IDT input tunable surface acoustic wave filter
Author :
Zhu, Jiahua ; Emanetoglu, Nuri W. ; Lu, Yicheng ; Kosinski, John A. ; Pastore, Robert A., Jr.
Author_Institution :
Motorola Inc., Piscataway, NJ, USA
Abstract :
Tunable surface acoustic wave (SAW) filters (TSF) have been widely used in the wireless telecommunication systems. A prototype of multi-IDT (interdigital transducer) input TSF has been developed. The device consists of 11 IDTs paralleled in the SAW propagation path. Different SAW filter configurations are realized by selecting or combining various IDTs, resulting in the tunability of both center frequency and 3 dB bandwidth. The center frequencies of the SAW filter range from 126.8 to 199.1 MHz; the 3 dB bandwidths range from 15.2 to 58.9 MHz. Impedance weighting methods have been applied. The passband ripple has been reduced from 6.44 to 1.37 dB after resistance weighting.
Keywords :
UHF filters; band-pass filters; circuit tuning; interdigital transducers; surface acoustic wave filters; 126.8 to 199.1 MHz; 15.2 to 58.9 MHz; 3 dB bandwidth; SAW propagation path; center frequency; impedance weighting methods; multi-IDT design; passband ripple; resistance weighting; tunable surface acoustic wave filter; wireless telecommunication systems; Acoustic propagation; Acoustic transducers; Acoustic waves; Bandwidth; Frequency; Impedance; Prototypes; SAW filters; Surface acoustic wave devices; Surface acoustic waves;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
