Surface acoustic wave filter
CA 1237174 A · Owner: American Telephone And Telegraph Company · Inventors: Meeker, Thrygve R.; Tsay, Wei-Shin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, A surface acoustic wave (SAW) filter is disclosed which exhibits both low insertion loss and small ripple in the passband requirements which wre considered mutually exclusive in the prior art. In accordance with the present invention, apodized group-type recessed electrodes are utilized to form the transducers. The grouping of the electrodes functions to reduce reflection between electrodes and apodization of the electrodes functions to increase the sideband rejection. However merely combining these techniques is inadequate since the apodization process produces additional ripple between adjacent electrodes, thus increasing the passband ripple. By recessing the apodized groups of …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted May 24, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 24, 2005.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.