Cordless time-duplex phone with improved hearing-aid compatible mode
CA 2242873 A1 · Owner: Torstensson, Anders · Inventors: Torstensson, Anders; Dent, Paul Wilkinson
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Techniques for providing a hearing aid compatible mode of transmission for a mobile station in a radio communication system are described. By adjusting a transmission envelope of a mobile station which transmits information in a burst fashion, harmonics which would normally be introduced into a hearing aid placed in close proximity with the mobile station are avoided. The modified transmission envelope provides a more gradual up and down-ramping of power to the transmitter to avoid introducing harmonics in the audio frequencies. This service can be provided at a system level in a manner which will avoid unnecessarily reducing system capacity by for example, authenticating a , user's …
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 January 17, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 17, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 17, 2019.
- 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.