Frequency responses of SAW filters with slanted finger interdigital transducers

The scattering characteristics of SAW filters with slanted finger interdigital transducers (SFITs), which configure many subfilters in parallel connection, are investigated using the transmission matrix method. The overlap width of each subfilter is adjusted to retain passband responses as flat as possible. The gap between input and output SFITs is tuned to reduce the passband ripple. A two-step weighting technique is employed to decrease the sideband level. Simulation results shown that a broadband IF filter can be designed by tailoring SAW SFITs.