Developed FORTRAN IV program to design surface acoustic wave(SAW) filter. Interdigital comb electrode pattern to be forked on piezo plate material for SAW filter is automatically, optimally designed in computer based on input data for filter characteristic and parameters for piezo material.

The program is composed of main program and several subroutine programs as fast foulier transform(FFT), inverse FFT, window function, filter characteristic calculatoin base on electric-acoustic equivalent circuit model, interdigital comb electrode pattern,

Feedback loop calculation is performed till reaching acceptable error range between the desired filter characteristic and the calculation based on electric-acoustic equivalent circuit model,

in this way, a characteristic of the interdigital comb electrode pattern on the surface of piezo material is optimized,

and finally mask pattern data are put out.

• 160MHz symmetric band pass SAW filter formed on lithium niobate substrate, prototyped in 1981.






• 58MHz asymmetric band pass SAW filter formed on lithium niobate substrate, prototyped in 1980.

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Last update 10/10 2018