Patent ID: 6664871
Filing Date: 2003-12-16
Classification: H03H

Abstract:
A surface acoustic wave filter system comprising:a first filter including a first piezoelectric substrate, a first input transducer on the first piezoelectric substrate for generating and transmitting a first surface acoustic wave having a predetermined wavelength &lgr; from an input electrical signal having a predetermined frequency, and a first output transducer for receiving and converting the first surface acoustic wave to a first filtered electrical signal; a second filter cascaded in series with the first filter and including a second piezoelectric substrate, a second input transducer for generating and transmitting a second surface acoustic wave from the first filtered electrical signal, and a second output transducer for receiving and converting the second surface acoustic wave to a second filtered electrical signal; wherein the first input transducer of the first filter is separated from the second input transducer of the second filter by a distance of (n+Â½)&lgr;(mâˆ’1), where n is an integer greater than or equal to 0, and m is either 2 if the time spur is feedthrough or an odd integer greater than 1 if the time spur is the mth transit echo, to enhance system time spur suppression.