The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 19, 1976
Filed:
Jan. 02, 1976
Adrian J DeVries, Elmhurst, IL (US);
Zenith Radio Corporation, Chicago, IL (US);
Abstract
An acoustic surface wave filter has offset transmitting and receiving transducers formed on the wave propagating surface of a piezoelectric substrate. A two-segment multistrip coupler is interposed on the propagating surface and provides 'track switching' or 'sidestepping' action for signals within the coupler passband. The coupler includes a split-connected portion formed by electrically connected filamentary conductor pairs and a split-isolated portion formed by electrically continuous filamentary conductors and interleaved conductors having a discontinuity at their center. The split-connected portion attenuates the symmetrical mode components of acoustic waves within the coupler stop band while the split-isolated portion attenuates the anti-symmetrical mode portion of acoustic waves within the coupler stop band, producing an improved trap response.