An acoustic loss unit measures the acoustic loss, defined to be the energy of the far-end speech signal divided by the energy of the near end signal. The rate at which a frame of data is encoded in a variable rate communications system may be indicative of the presence or absence of speech. A rate estimator determines the rate of the far-end speech signal and the rate of the near-end signal. Filter adaptation is controlled by a controller based on the rate of the far-end speech signal, the rate of the near-end signal, an acoustic loss measure, and a double talk hangover indicator. The echo canceller comprises an adaptive filter that tracks the impulse response of the echo path and produces an estimate of the echo. The echo canceller of the present invention may be implemented in systems having limited processing resources. The present invention is an improved apparatus and method for echo cancellation. for suppressing echoes for one or both directions of traffic using echo cancellers H04M9/082- Two-way loud-speaking telephone systems with means for conditioning the signal, e.g.for suppressing echoes for one or both directions of traffic H04M9/08- Two-way loud-speaking telephone systems with means for conditioning the signal, e.g.H04M9/00- Arrangements for interconnection not involving centralised switching.238000006011 modification reactions Methods 0.000 description 1.238000006731 degradation reactions Methods 0.000 description 1.230000015556 catabolic process Effects 0.000 description 1.280000281494 Independent Energy companies 0.000 description 1.281000095707 Digital Systems companies 0.000 description 1.238000003786 synthesis reactions Methods 0.000 description 2.230000015572 biosynthetic process Effects 0.000 description 2.238000004458 analytical methods Methods 0.000 description 3.230000005540 biological transmission Effects 0.000 description 5.230000002194 synthesizing Effects 0.000 claims description 3.230000004301 light adaptation Effects 0.000 claims abstract description 32.206010019133 Hangover Diseases 0.000 claims abstract description 35.230000003044 adaptive Effects 0.000 claims abstract description 38.238000002592 echocardiography Methods 0.000 title claims abstract description 131.Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.) Filing date Publication date Priority to US6656297P priority Critical Priority to US09/199,530 priority patent/US6563803B1/en Application filed by Qualcomm Inc filed Critical Qualcomm Inc Priority to US10/368,888 priority patent/US7031269B2/en Publication of US20030174661A1 publication Critical patent/US20030174661A1/en Application granted granted Critical Publication of US7031269B2 publication Critical patent/US7031269B2/en Adjusted expiration legal-status Critical Status Expired - Fee Related legal-status Critical Current Links Original Assignee Qualcomm Inc Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.) ( en Inventor Way-Shing Lee Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) Expired - Fee Related, expires Application number US10/368,888 Other versions US20030174661A1
#Where to find acoustic echo cancellation pdf#
Google Patents US7031269B2 - Acoustic echo cancellerÄownload PDF Info Publication number US7031269B2 US7031269B2 US10/368,888 US36888803A US7031269B2 US 7031269 B2 US7031269 B2 US 7031269B2 US 36888803 A US36888803 A US 36888803A US 7031269 B2 US7031269 B2 US 7031269B2 Authority US United States Prior art keywords signal rate far energy speech Prior art date Legal status (The legal status is an assumption and is not a legal conclusion.