Patent ID: 6351197
Filing Date: 2002-02-26
Classification: H03H

Abstract:
A surface acoustic wave filter, comprising:a substrate having mutually parallel tracks for surface acoustic waves; at least three resonators in said tracks, each of said resonators having reflectors, an interdigital transducer disposed between two of said reflectors, a pair of electrical connections, and a plurality of electrode fingers disposed at a finger periodicity; said resonators including a first type of resonator connected in series through said connections and a second type of resonator connected in parallel with said first type of resonator; and said resonators including n series-connected resonators Rs1, . . . Rsx, . . . Rsn having a different finger periodicity ps1, . . . psx, . . . psn of said electrode fingers in said interdigital transducers, wherein n and x are integers, n&gE;3 and 1sxs1sn.