JPS6412728A - Echo canceller - Google Patents
Echo cancellerInfo
- 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
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.
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)
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 |
-
1987
- 1987-07-07 JP JP17011487A patent/JPS6412728A/en active Pending
Cited By (5)
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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