JPS5792926A - Echo cancelling device - Google Patents

Echo cancelling device

Info

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
side tone
circuit
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
Application number
JP16859180A
Inventor
Tadamichi Kawasaki
Shigenobu Minami
Original Assignee
Toshiba Corp
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 Toshiba Corp filed Critical Toshiba Corp
Priority to JP16859180A priority Critical patent/JPS5792926A/en
Publication of JPS5792926A publication Critical patent/JPS5792926A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B3/00Line transmission systems
    • H04B3/02Details
    • H04B3/20Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
    • H04B3/23Reducing 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
    • H04B3/238Reducing 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.
JP16859180A 1980-11-29 1980-11-29 Echo cancelling device Pending JPS5792926A (en)

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)

* Cited by examiner, † Cited by third party
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 Communications Satellite Corp 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

Cited By (7)

* Cited by examiner, † Cited by third party
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 Communications Satellite Corp 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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