JPS6412728A - Echo canceller - Google Patents

Echo canceller

Info

Publication number
JPS6412728A
JPS6412728A JP17011487A JP17011487A JPS6412728A JP S6412728 A JPS6412728 A JP S6412728A JP 17011487 A JP17011487 A JP 17011487A JP 17011487 A JP17011487 A JP 17011487A JP S6412728 A JPS6412728 A JP S6412728A
Authority
JP
Japan
Prior art keywords
mean power
long time
mean
comparator
calculation circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP17011487A
Other languages
Japanese (ja)
Inventor
Kaoru Yamamoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP17011487A priority Critical patent/JPS6412728A/en
Publication of JPS6412728A publication Critical patent/JPS6412728A/en
Pending legal-status Critical Current

Links

Landscapes

  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To improve an echo erasing characteristic, by identifying a voice signal from a noise by finding a mean power for a short time or a long time of an input signal on a transmission side, and combining an identified result with the detection of double talk. CONSTITUTION:An identification circuit 14 is constituted of a mean power calculation circuit 21 which calculates the mean value for constant short time or long time, a comparator 22 which compares the output of the mean power calculation circuit 21 with a prescribed threshold value, a counter 23 which counts the output of the comparator 22, and a comparator 24 which compares the count value of the counter 23 with the prescribed threshold value. The mean power calculation circuit 21 calculates the mean power for the short time or that for the long time for the input signal on the transmission side. By using both mean powers for the short and long time and taking the AND of the output results, respectively, more accurate identification can be performed.
JP17011487A 1987-07-07 1987-07-07 Echo canceller Pending JPS6412728A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17011487A JPS6412728A (en) 1987-07-07 1987-07-07 Echo canceller

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17011487A JPS6412728A (en) 1987-07-07 1987-07-07 Echo canceller

Publications (1)

Publication Number Publication Date
JPS6412728A true JPS6412728A (en) 1989-01-17

Family

ID=15898898

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17011487A Pending JPS6412728A (en) 1987-07-07 1987-07-07 Echo canceller

Country Status (1)

Country Link
JP (1) JPS6412728A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62289518A (en) * 1986-05-27 1987-12-16 Sunstar Inc Composition containing stably blended minocycline
US5513265A (en) * 1993-05-31 1996-04-30 Nec Corporation Multi-channel echo cancelling method and a device thereof
US6389440B1 (en) * 1996-04-03 2002-05-14 British Telecommunications Public Limited Company Acoustic feedback correction
US6566350B2 (en) 2000-05-23 2003-05-20 Showa Yakuhin Kako Co., Ltd. Minocycline-containing compositions
JP2007060429A (en) * 2005-08-25 2007-03-08 Matsushita Electric Works Ltd Voice amplifying phone

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62289518A (en) * 1986-05-27 1987-12-16 Sunstar Inc Composition containing stably blended minocycline
US5513265A (en) * 1993-05-31 1996-04-30 Nec Corporation Multi-channel echo cancelling method and a device thereof
US6389440B1 (en) * 1996-04-03 2002-05-14 British Telecommunications Public Limited Company Acoustic feedback correction
US6566350B2 (en) 2000-05-23 2003-05-20 Showa Yakuhin Kako Co., Ltd. Minocycline-containing compositions
JP2007060429A (en) * 2005-08-25 2007-03-08 Matsushita Electric Works Ltd Voice amplifying phone

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