Elliptic filter and method of making the same
CA 2262977 C · Owner: Pradal, Bortolo M. · Inventors: Pradal, Bortolo M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An odd order N-pole, (N-1)/2 zero elliptic filter (300) is provided having (N- 1)/2 BAW resonators (302 and 304). The first Bulk Acoustic Wave (BAW) resonator (302) operates at a first mode number and a first center frequency and the second BAW resonator (304) operates at a second mode number and a , first centre frequency. Operating BAW resonators (302 and 304) at differing modes allows the unwanted passbands (201) of the first BAW resonators (302) to be attenuated by the stopband of the second BAW resonator (304) and vice versa.
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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
- Filed July 1, 1997 and granted November 6, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 1, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 1, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
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.