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:
Aug. 17, 2004
Filed:
Aug. 15, 2002
Andreas Bergmann, Haiming, DE;
Jurgen Franz, Frankfurt am Main, DE;
Epcos AG, Munich, US;
Abstract
A transducer includes base cells each having a length &lgr;, where &lgr; is a wavelength of a center frequency of the transducer. The base cells are arranged in a direction of propagation of a surface acoustic wave. The base cells include exciting base cells and reflecting base cells. The exciting base cells each have a same number of electrode fingers. Each base cell has a reflection portion. The reflection portion of each base cell has a same value mRo, where m is one of −2, −1, 0, 1, or 2 and Ro is a reference reflection. Each non-zero reflection portion in each base cell has a same phase position. Excitation and reflection in the transducer are equal in phase in one direction of propagation of the surface acoustic wave and opposite in phase in an opposite direction of propagation of the surface acoustic wave.