Structure of a duplexer for radio equipment
CA 2018050 C · Owner: Nec Corporation · Inventors: Ueda, Hideki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A structure of a duplexer for duplex radio equipment has a transmission circuit board loaded with a transmitter section and a transmit filter for filtering a high frequency signal fed from the transmitter section. A reception circuit board physically independent of the transmission circuit board is loaded with a receive filter for filtering a received high frequency signal and a receiver section for receiving the high frequency signal from the receive filter. A connection circuit board mechanically connects the transmission circuit board and reception circuit board and is loaded with a matching circuit for matching the phase of the high frequency signal to be inputted to the receive filter …
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 1, 1990 and granted November 29, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 1, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 1, 2012.
- 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.