Multiplex communications – Crosstalk suppression
Reexamination Certificate
2008-04-01
2008-04-01
Chan, Wing (Department: 2619)
Multiplex communications
Crosstalk suppression
C370S289000, C370S290000, C379S406050, C379S406080
Reexamination Certificate
active
07352687
ABSTRACT:
A method and apparatus for reducing crosstalk in a multi-channel communication system is disclosed. In one embodiment, outgoing signals in a multi-channel environment are manipulated into a transform domain, such as the frequency domain. Thereafter, the signals may be combined and modified based on a weighting variable to create a cancellation signal. Combined processing greatly reduces system complexity and increases processing speed. After processing in the transform domain, the cancellation signal undergoes further processing to return the cancellation signal into the time domain. The cancellation signal may then be combined with received signals to cancel crosstalk or echo. A method and apparatus for crosstalk cancellation in the analog domain and digital domain are also disclosed. Cancellation at least partially in the analog domain reduces the dynamic range requirements for digital to analog converters within the front-end processing system of a receiver and thereby reduces clipping and increases operating speed.
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Jones William W.
Pagnanelli Christopher Jude
Zimmerman George A.
Chan Wing
Sefcheck Gregory B.
Solarflare Communications, Inc.
Weide & Miller Ltd.
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