Apparatus and method for voice band reduction
CA 2107116 C · Owner: Neil, J. Philip · Inventors: Neil, J. Philip
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An apparatus for frequency band reduction of a voice signal having an upper and lower band limit including a voice signal input. A clipping circuit clips the positive and negative peaks of the voice signal connected to the voice signal input. A bandpass filter is connected to the clipping circuit for rejecting harmonics created by the clipping circuit. A low and high end roll-off filter device is provided for producing a given db/octave frequency roll off at the lower bandlimit. The geometric mean value of the upper and lower bandlimit falls within a given lowerand a given upper frequency range.
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 May 8, 1992 and granted December 9, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 8, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 8, 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.