Radio equipment directional coupler
CA 2094504 C · Owner: Schumacher, Lawrence R. · Inventors: Schumacher, Lawrence R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A directional coupler (103) for radio equipment couples a radio frequency signal from an input of a microstrip transmission line (309) to an output and provides a directionally coupled output via a stripline microstrip (311). Open circuit microstrip transmission line stubs (313 and 315) are tuned to a quarter wavelength of the third harmonic of the radio frequency to provide third harmonic rejection within the directional coupler.
Read the whole patent
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 August 10, 1992 and granted May 6, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 10, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 10, 2014.
- 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.