ANORDNING FOER UNDERTRYCKANDE AV FELAKTIGA DAEMPNINGSPOLER I KRISTALLFILTER

摘要

Piezoelectric filter includes a piezoelectric substrate having an upper and lower opposed major surfaces. A plurality of N coupled resonators where N is an integer greater than two exposed on the surface of the substrate. A plurality of mounting pedestals are utilized to couple the resonators to ground in a manner such that no two non-adjacent resonators are coupled to any one pedestal. This mounting scheme suppresses undesired spurious attenuation poles and improves the selectivity of the piezoelectric filter.