Design of surface-acoustic-wave filters by taking account of electrical terminations and matching circuits

This letter describes a method of determining overlap width for interdigital electrodes of s.a.w. filters by taking account of electrical terminations and matching circuits. A filter with 22.5% bandwidth is designed by use of damped least squares. Since the amplitude response in the passband can be considerably improved compared with that designed by a Fourier analysis, this method may be useful when the required passband shape is strictly specified.