WEIGHTING SURFACE WAVE INTERDIGITAL TRANSDUCERS BY WITHDRAWING ELECTRODE FINGERS

摘要

1471995 Surface wave transducers TEXAS INSTRUMENTS Inc 16 July 1974 [10 Aug 1973] 31437/74 Heading H3U An interdigital surface wave transducer with a desired impulse response is provided by omitting one or more selected fingers from an otherwise conventional transducer having fingers of equal length and width and having an impulse response which has the same zerocrossings as the desired impulse response and which, if the fingers were not omitted, would have an envelope function which was everywhere greater than or equal to that of the desired impulse response. In a method of determining which fingers to omit, fingers are omitted so as to render the actual envelope function approximately equal to the desired function along the transducer. The finger spacing may be uniform or may correspond to a linear FM chirp. The transducer may comprise split fingers.