Composite duplex filter
CA 2097944 C · Owner: Mitsubishi Denki Kabushiki Kaisha · Inventors: Nakata, Izumi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A miniaturized portable telephone is provided in which a receiving radio-frequency filter is formed by a SAW filter while a, transmitting radio-frequency filter is formed by a dielectric filter and they are mounted on a substrate. The transmitting and receiving sides are connected to an antenna by transmission lines the length of which is set to have a high impedance in the mutual transmitting and receiving frequency.
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 June 8, 1993 and granted April 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 8, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 8, 2015.
- 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.