EP0111938B1
Expired / Lapsed
EP
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Fast convergence method and system for echo canceller
Assignee: NEC Corp
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Filing: 1983-12-21
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Granted: 1988-03-30
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Expires: 2003-12-21
Abstract
No abstract record available.
Inventors
- 👤 Akira Kanemasa
- 👤 Kunihiko Niwa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 06:58
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/20; H04B3/23; H04B3/238
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
101 words
A fast convergence method for an echo canceller comprising the steps of: (a) generating an echo replica (e'(k)) in response to a transmit signal; (b) producing a difference signal by subtracting the echo replica (e'(k)) from a signal which contains a received signal and echo; and (c) adaptively varying a tap correction amount of a filter (20) which generates the echo replica; characterized by (d) multiplying and then averaging the difference signal and a polarity of the echo replica; and (e) adaptively varying the tap correction amount of the filter (20) in accordance with an absolute value of the averaged output.
Claim 2
Dependent Claim
101 words
A fast convergence method for an echo canceller comprising the steps of: (a) generating an echo replica (e'(k)) in response to a transmit signal; (b) producing a difference signal by subtracting the echo replica (e'(k)) from a signal which contains a received signal and echo; and (c) adaptively varying a tap correction amount of a filter (20) which generates the echo replica; characterized by (d) multiplying and then averaging the difference signal and a polarity of the echo replica; and (e) adaptively varying the tap correction amount of the filter (20) in accordance with an absolute value of the averaged output.
Claim 3
Dependent Claim
109 words
A fast convergence system for an echo canceller comprising: (a) means for generating an echo replica (e'(k)) in response to a transmit signal; (b) means (22) for producing a difference signal by subtracting the echo replica (e'(k)) from a signal which contains a received signal and echo; and (c) means for adaptively varying a tap correction amount of a filter (20) of the echo canceller, characterized by (d) means (56, 54, 58) for multiplying and then averaging the difference signal and a polarity of the echo replica (e'(k)); and (e) means (60,62, 52) for generating the tap correction amount in accordance with an absolute value of the averaged output.
Claim 4
Dependent Claim
109 words
A fast convergence system for an echo canceller comprising: (a) means for generating an echo replica (e'(k)) in response to a transmit signal; (b) means (22) for producing a difference signal by subtracting the echo replica (e'(k)) from a signal which contains a received signal and echo; and (c) means for adaptively varying a tap correction amount of a filter (20) of the echo canceller, characterized by (d) means (56, 54, 58) for multiplying and then averaging the difference signal and a polarity of the echo replica (e'(k)); and (e) means (60,62, 52) for generating the tap correction amount in accordance with an absolute value of the averaged output.
Claim 5
Dependent Claim
45 words
A fast convergence system for an echo canceller according to claim 2, characterized by means (64) for absorbing a fluctuation in the absolute value of the averaged output, the output of said fluctuation absorbing means (64) varying the tap correction amount of the filter (20).
References Cited (Backward Citations)
No citation records indexed.
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