Telephonic communications – Echo cancellation or suppression – Residual echo cancellation
Reexamination Certificate
2005-06-16
2010-12-21
Tsang, Fan (Department: 2614)
Telephonic communications
Echo cancellation or suppression
Residual echo cancellation
C379S406080
Reexamination Certificate
active
07856097
ABSTRACT:
Providing echo canceling apparatus, telephone set using the same and an echo canceling method that do not require transmission/reception sound detection and are resistant to environmental noise.Echo canceling apparatus according to the invention includes a calculator4for subtracting a pseudo-echo signal pec generated from a reception sound signal from an echo signal ec that is based on an echo generated when the reception sound that is based on the reception sound signal is reflected on a reflective body such as a wall thereby outputting a residual echo signal rec. The echo canceling apparatus further includes a residual echo detector12for estimating a residual echo volume by detecting sign inversion of the echo signal ec and the residual echo signal rec and their amplitude values. It is thus possible to compare between the positive and negative signs of the input/output signal of the calculator4without using the transmission/reception sound detection to detect the generation of a pseudo-echo signal thereby accurately estimating the residual echo volume.
REFERENCES:
patent: 5434916 (1995-07-01), Hasegawa
patent: 5600714 (1997-02-01), Eppler, Jr. et al.
patent: 5887059 (1999-03-01), Xie et al.
patent: 6148072 (2000-11-01), Huang
patent: 6148078 (2000-11-01), Romesburg
patent: 6553122 (2003-04-01), Shimauchi et al.
patent: 6622030 (2003-09-01), Romesburg et al.
patent: 2004/0170271 (2004-09-01), Kubota
patent: 02288428 (1990-11-01), None
patent: 04271622 (1992-09-01), None
patent: 6188789 (1994-07-01), None
patent: 09116471 (1997-05-01), None
patent: 2002501336 (2002-01-01), None
patent: 0203563 (2002-01-01), None
patent: 03044978 (2003-05-01), None
Rong-Yih Chen, et al., “One the Optimum Step Size for the Adaptive Sign and LMS Algorithms,” IEEE Transactions on Circuits and Systems, IEEE Inc., New York, vol. 37, No. 6, XP000149018, pp. 836-840, Jun. 1, 1990.
Chen et al. “On the Optimum Step Size for the Adaptive Sign and LMS Algorithms” (Hereinafter referred to as Chen).
International Search Report dated Oct. 28, 2005.
Rong-Yih Chen, et al., “On the Optimum Step Size for the Adaptive Sign and LMS Algorithms,” IEEE Transactions on Circuits and Systems, IEEE Inc., New York, vol. 37, No. 6, XP000149018, pp. 836-840, Jun. 1, 1990.
Dickinson Wright PLLC
Panasonic Corporation
Sharifzada Ibraham
Tsang Fan
LandOfFree
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