Telephonic communications – Subscriber line or transmission line interface – Network interface device
Patent
1995-09-26
1997-10-07
Zele, Krista M.
Telephonic communications
Subscriber line or transmission line interface
Network interface device
379 3, 379406, 370 321, H04B 320, H04M 900
Patent
active
056756445
ABSTRACT:
A method and apparatus for detecting and correcting for variations in the flat delay, which permits smooth echo canceller operation even under dynamic delay conditions. In a delay monitor, the received signal is compared against delayed versions of the echo estimate to determine whether a shift in the echo delay has occurred. If such a shift in delay has occurred then a signal indicating the amount of the shift is to the adaptive filter of the echo canceller and the filter taps are updated in accordance with the delay shift value.
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English Sean
Kumar Devendra T.
Miller Russell B.
Qualcomm Incorporated
Zele Krista M.
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