Compatible am stereo broadcast system
CA 1095992 A · Owner: Motorola, Inc. · Inventors: Hilbert, Francis H.; Parker, Norman W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A compatible AM stereo broadcast system has a pair of carriers in quadrature are separately modulated with stereo information. The resulting signal is multiplied by the cosine of an angle ?, the angle between the vector sum of the two carriers and a line that bisects the angle between the carriers in quadrature. The signal envelope contains the sum of the information on the two channels thus providing, compatible monophonic reception. In a stereo receiver the two carriers in quadrature can be restored by dividing the signal by the cosine of the angle ?. The original modulation can be obtained from each channel by product detection.
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
- Granted February 17, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 17, 1998.
- 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.