Simple analytical expressions involving Bessel functions are obtained for various window functions. Some of the windows take the form of Kaiser-Bessel and Dolph-Chebyshev functions. The performance of various windows is evaluated with respect to shape factor and sidelobe level. Design data is presented for designing the surface acoustic-wave (SAW) filters using smooth window functions. The design of SAW filters using sin (t)/t-type apodization profile is outlined for various window functions. For given filter specifications, such as center frequency, 3-dB bandwidth, shape factor, and sidelobe level, the design procedure is used to compute the apodized transducer length and apodization profile.
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