ABSTRACT Withdrawal weighted (WW) fan-shaped interdigital transducers (FIDT) are used to design surface acoustic wave (SAW) filters with a good shape factor, a flat passband, and an out-of- band rejection of 50 dB and more. Utilization of "stepped" actions as a weighting action for FIDT's ensures a simple filter structure synthesis procedure that does not take a long time on a personal computer. Three modifications of SAW filters with 2% bandwidth, in-band ripple of 0.1 dB, and out-of-band rejection of 50-55 dB have been fabricated on ST-quartz.
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