JPS5792926A - Echo cancelling device - Google Patents
Echo cancelling deviceInfo
- Publication number
- JPS5792926A JPS5792926A JP16859180A JP16859180A JPS5792926A JP S5792926 A JPS5792926 A JP S5792926A JP 16859180 A JP16859180 A JP 16859180A JP 16859180 A JP16859180 A JP 16859180A JP S5792926 A JPS5792926 A JP S5792926A
- Authority
- JP
- Japan
- Prior art keywords
- loss
- circuit
- side tone
- hybrid
- echo
- 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
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/02—Details
- H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
- H04B3/23—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other using a replica of transmitted signal in the time domain, e.g. echo cancellers
- H04B3/238—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other using a replica of transmitted signal in the time domain, e.g. echo cancellers using initial training sequence
Abstract
PURPOSE:To make the insertion loss proper, to make a sevice without the impresstion of swtching prossible, and to prevent howling effectively, by using effectively merits of the echo canceller system and the voice switch. CONSTITUTION:A switch circuit 15 receives the control of a control circuit 17 to supply a training signal from a training signal generator 16 to a hybrid 3, and an echo canceller circuit 18 estimates an echo path (side tone characteristics) of the hybrid 3 on a basis of the training signal and the side tone from the hybrid 3, and a loss determining circuit 14 determines loss quantities of variable loss circuits 11 and 12 on a basis of the side tone level. The echo canceller circuit subtracts a false side tone from the receiving signal, and a comparing circut 13 compares the output level of an amplifier 5 and the output level of the echo can celler 18 with each other to insert the loss quantity to the transmissin line at the receiving time and insert it to the receiving line at the transmission time.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16859180A JPS5792926A (en) | 1980-11-29 | 1980-11-29 | Echo cancelling device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16859180A JPS5792926A (en) | 1980-11-29 | 1980-11-29 | Echo cancelling device |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5792926A true JPS5792926A (en) | 1982-06-09 |
Family
ID=15870888
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP16859180A Pending JPS5792926A (en) | 1980-11-29 | 1980-11-29 | Echo cancelling device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5792926A (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5921139A (en) * | 1982-07-28 | 1984-02-03 | Toshiba Corp | Echo canceller system |
JPS5943637A (en) * | 1982-07-30 | 1984-03-10 | コミユニケイシヨンズ・サテライト・コ−ポレイシヨン | Echo canceller |
JPS59205833A (en) * | 1983-05-09 | 1984-11-21 | Nec Corp | Device for suppressing stray signal |
JPS61146058A (en) * | 1984-12-20 | 1986-07-03 | Nec Corp | Conference telephone system |
JPS63160428A (en) * | 1986-12-23 | 1988-07-04 | Nec Corp | Two-wire voice conference device |
JPS63202138A (en) * | 1987-02-17 | 1988-08-22 | Nec Corp | 2-wire type voice conference equipment |
-
1980
- 1980-11-29 JP JP16859180A patent/JPS5792926A/en active Pending
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5921139A (en) * | 1982-07-28 | 1984-02-03 | Toshiba Corp | Echo canceller system |
JPH0374538B2 (en) * | 1982-07-28 | 1991-11-27 | ||
JPS5943637A (en) * | 1982-07-30 | 1984-03-10 | コミユニケイシヨンズ・サテライト・コ−ポレイシヨン | Echo canceller |
JPS59205833A (en) * | 1983-05-09 | 1984-11-21 | Nec Corp | Device for suppressing stray signal |
JPS61146058A (en) * | 1984-12-20 | 1986-07-03 | Nec Corp | Conference telephone system |
JPS63160428A (en) * | 1986-12-23 | 1988-07-04 | Nec Corp | Two-wire voice conference device |
JPS63202138A (en) * | 1987-02-17 | 1988-08-22 | Nec Corp | 2-wire type voice conference equipment |
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