07058368 is referenced by 68 patents and cites 22 patents.

A method and apparatus for noise cancellation in communications systems. The method is applicable in situations where an interfering signal or noise must be cancelled within a specified bandwidth. A sample of the interfering signal is used to synthesize a cancellation signal which is of equal amplitude but opposite phase to the original interference signal. Introduction of the cancellation signal into the interference signal path results in substantially complete suppression of the interference signal through vector subtraction of the superposed signal fields. Adaptive cancellation is also provided in that the frequency and bandwidth of the cancellation signal can be controlled. The adaptive nature of the cancellation loop also tracks out imbalances between the interference and cancellation signals caused by temperature variation and component tolerances. The adaptive nature of the cancellation system also allows the system to lock onto and track an interfering signal.

Title
Adaptive feedforward noise cancellation circuit
Application Number
10/185118
Publication Number
7058368 (B2)
Application Date
June 27, 2002
Publication Date
June 6, 2006
Inventor
Alain Roussel
Gatineau
CA
Charles T Nicholls
Nepean
CA
Agent
Barnes & Thornburg
Assignee
Nortel Networks
CA
IPC
H04M 9/00
H04L 25/03
H04B 1/00
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