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:
Apr. 03, 2001
Filed:
Mar. 05, 1999
Guenter Martin, Dresden, DE;
Dover Europe GmbH, Steinbach/Ts, DE;
Abstract
An improvement of a surface acoustic wave component is disclosed. Surface acoustic wave components of the known type are changed in such a way that the dependency of the insertion loss and/or group delay time on the frequency as asymmetric function in relation to the center frequency can be realized in a predetermined manner. Sloping passbands are particularly significant in this respect. As disclosed, in a surface acoustic wave component in which two single-phase unidirectional transducers which are composed of finger groups comprising a pair of fingers and a reflection finger are arranged on a piezoelectric substrate, wherein the two fingers of the pair of fingers have opposite polarity and are at a distance of one quarter wavelength from one another, at least one base element in at least one of the single-phase unidirectional transducers differs from the rest of the base elements with respect to its distance between the center of the reflection finger and the center of the nearest finger of its pair of fingers. The device of the invention is applicable, for example, for bandpass filters with a relative bandwidth of up to several percent and for oscillators.