Presentacin de PowerPoint

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Echo Cancellation In Conversational Systems
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Utterance
Response
S
False Input
Bad Output
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Barge-in Echo False user input ? Bad
output False barge-in ? Commutication
fails Additive noise ? System degradation
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System Characteristics Echo generation High
order FIR filtering High variability
position, temperature...
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Adaptation
White Noise - N256
White Noise - N1024
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Adaptation
White Noise - N1024
Voice - N1024
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NLMS Standard NLMS Subband NLMS Block
NLMS Frequency NLMS
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Noise Ambient noise Measurement noise Other
speech Quantification noise Residual echo
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Adaptation With Noise Adaptation? Noise ? Error
? No adaptation Changes ? Error ? Fast
adaptation Voice Activity Detector Correlation St
ate-based control Fuzzy logic Neuronal networks
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Adaptation With Noise
Sup
-
C
S
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Summary Acoustic echoes Echo canceller Adaptati
on control Echo supressor