Patent ID: 6313717
Filing Date: 2001-11-06
Classification: H03H,Y10T

Abstract:
A surface acoustic wave filter comprising transducers, each transducer being defined by a weighting function representing a distribution of centers of reflection and centers of transduction of said transducer, said filter having a passband and a rejection band and comprising:a first channel comprising at least one first input transducer and one first output transducer defining a first transfer function, said first channel having a first resultant weighting function;a second channel comprising at least one second input transducer and one second output transducer defining a second transfer function, said second channel having a second resultant weighting function;wherein the first and second input transducers are electrically connected to each other;wherein the first and second output transducers are electrically connected to each other;wherein the resultant weighting functions of the first and second channels are different and such that transfer functions of the first channel and of the second channel are in phase in the passband of the filter and in antiphase in the rejection band of the filter; andwherein at least one of the first and second input and output transducers are series connected.