Method and apparatus for frame-bit modulation and demodulation of ds3signal
CA 1279734 C · Owner: Alberta Telecommunications Research Centre · Inventors: Grover, Wayne D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of modulating a DS3 signal for addition thereto of an auxiliary, transparent signalling channel the DS3 signal having frame-finding bits (F-bits) which provide a predetermined pattern for which frame-finding circuits hunt to demultiplex the payload of the DS3 signal. The method comprises cyclically forcing an F-bit error onto every D-spaced F-bit of the DS3 signal during an initial ON period of a modulation cycle the, ON period and the modulation cycle having lengths such that no more than two verification attempts are required to complete reframing of the signal during demodulation and wherein the Modulation Spacing, D, is selected so as to provide a low probability of coincidence …
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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 January 29, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 29, 2008.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.