Telephonic communications – Subscriber line or transmission line interface – Network interface device
Patent
1995-08-25
1997-09-02
Zele, Krista M.
Telephonic communications
Subscriber line or transmission line interface
Network interface device
379406, 379407, 379411, H04M 908, H04B 323
Patent
active
056640110
ABSTRACT:
An echo canceller includes receive and send paths each having an input and output port, a first non-adaptive filter with first filter coefficients for generating a first replica signal in response to a receive input signal, a second adaptive filter with second filter coefficients for generating a second replica signal in response to the receive input signal, a first subtracter for generating a send output signal representing a difference between a send input signal and the first replica signal, a second subtracter for generating an error signal representing a difference between the send output signal and the second replica signal, and a controller for replacing the first filter coefficients by the sum of the first and second filter coefficients and for resetting the second filter coefficients in response to a calculation that includes a first quantity associated with the send output signal and a second quantity associated with the error signal.
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Crochiere Ronald Eldon
Iyengar Vasu
Lucent Technologies - Inc.
Saint-Surin Jacques M.
Sigmond David
Smith David L.
Zele Krista M.
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