Method of optimizing input impedance of surface acoustic wave filter

A method of designing a band-pass filter, comprising:

• establishing a baseline filter design meeting first design criteria, the baseline filter design including a plurality of surface acoustic wave resonators, each surface acoustic wave resonator having a respective resonant frequency, the plurality of surface acoustic wave resonators organized by resonant frequency into two or more groups;
• establishing one or more alternative filter designs, each of the one or more alternative filter designs derived from the baseline filter design by reordering the resonant frequencies of two or more of the plurality surface acoustic wave resonators within at least one of the two or more groups;
• calculating a respective performance metric related to an input impedance over a pass band of each of the baseline filter designs and the one or more alternative filter designs;
• and
• selecting a final filter design from among the baseline filter design and the one or more alternative filter designs based on the respective performance metrics.