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:
Sep. 28, 2004
Filed:
Apr. 25, 2002
Benjamin P. Abbott, Orlando, FL (US);
Joshua J. Caron, Altamonte Springs, FL (US);
Kamran S. Cheema, Apopka, FL (US);
Sawtek, Inc., Orlando, FL (US);
Abstract
A hybrid leaky surface acoustic wave (LSAW) resonator filter has a wide bandwidth, low insertion loss and return loss, and excellent rejection of frequencies outside the passband, and includes one or more longitudinally coupled LSAW resonator filter tracks with chirp-type resonant cavities, reflective gratings, and a plurality of interdigital transducers (IDTs) disposed end-to-end therebetween. An acoustic resonant cavity is formed between each of the IDTs and its neighboring IDTs or gratings by chirping the fingers of the IDTs in the vicinity of the cavity. A one or more LSAW impedance element filters are disposed upon the same substrate and connected in series and/or shunt with the longitudinally coupled LSAW resonator tracks. The frequencies of the LSAW impedance-element filters are chosen such that their combination with the longitudinally coupled LSAW resonator filter tracks results in the formation of deep nulls in the overall transfer function at frequencies just outside of the passband.