Planar dual mode filters and a method of construction thereof
CA 2197253 C · Owner: Ye, Shen · Inventors: Mansour, Raafat R.; Ye, Shen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A planar dual mode filter has one or more resonators with L-shaped sections that are oriented back to back to one another. The filter can be constructed by adjusting the size of a gap between the back to back sections and adjusting the offset distance between adjacent sections. Further coupling, between adjacent resonators can be controlled by adjusting a distance between the adjacent resonators. The filters can be co-planar stripline, suspended, microstripline or microstripline. The filters have a film on a substrate with a ground plane. The film can be gold, silver or copper or it can be a ceramic material that becomes superconductive at cryogenic temperatures.
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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 February 11, 1997 and granted November 17, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 11, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 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.