Cable television apparatus employing two-way communication
CA 2199815 C · Owner: Al-Khalil, Munther A. · Inventors: Thompson, Leo J.; Kruse, Herman A.; Al-Khalil, Munther A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A cable television system employs two-way communication between a headend (30) and at least one subscriber terminal (10). The two-way communication is provided by having separate frequency bands for each communication path. The frequency bands do not overlap and the higher frequency band is used for subscriber terminal to headend transmissions. A line amplifier (100) is provided that employs two diplex filters (110 140) each connected to both a , forward and reverse amplifier (120 130). The high pass portions of the diplex filters (330, 340, 201) are formed from both lumped and distributed components.
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 30, 1995 and granted July 24, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 30, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 30, 2017.
- 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.