Patent ID: 6380827
Filing Date: 2002-04-30
Classification: H03H

Abstract:
A surface acoustic wave filter comprising:a first serial-arm SAW resonator coupled to an input terminal; a first dual-mode SAW resonator coupled between said first serial-arm SAW resonator and an output terminal, wherein said first dual-mode SAW resonator includes first to third comb-shaped interdigital transducers, said second comb-shaped interdigital transducer is arranged between said first interdigital transducer and said third interdigital transducer and also coupled between the first serial-arm SAW resonator and the ground potential, and each of the first and third comb-shaped interdigital transducers is coupled between said ground potential and said output terminal; and a second dual-mode SAW resonator coupled between said first dual-mode SAW resonator and said output terminal.