JPS5733843A - Echo cancelling device - Google Patents

Echo cancelling device

Info

Publication number
JPS5733843A
JPS5733843A JP10828580A JP10828580A JPS5733843A JP S5733843 A JPS5733843 A JP S5733843A JP 10828580 A JP10828580 A JP 10828580A JP 10828580 A JP10828580 A JP 10828580A JP S5733843 A JPS5733843 A JP S5733843A
Authority
JP
Japan
Prior art keywords
signal
circuit
training
telephone set
prescribed time
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.)
Granted
Application number
JP10828580A
Other languages
Japanese (ja)
Other versions
JPS6340377B2 (en
Inventor
Shigenobu Minami
Tadamichi Kawasaki
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.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric Co 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 Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP10828580A priority Critical patent/JPS5733843A/en
Publication of JPS5733843A publication Critical patent/JPS5733843A/en
Publication of JPS6340377B2 publication Critical patent/JPS6340377B2/ja
Granted legal-status Critical Current

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

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To exactly execute estimation of an echo path characteristic, by sending out a discriminating signal which can be detected easily by the receiving side when starting and ending a training signal, and sending out the training signal after the training signal of the other telephone set has ended. CONSTITUTION:In case when a telephone set calls, a controlling circuit 15 sends a control signal to a selecting circuit 14 by a circuit connecting signal, and an outgoing and incoming discriminating signal from a loud telephone set 10, sends out a training start signal to the circuit for a prescribed time, and in this case, to a side tone cancelling circuit 18 is sent a signal for inhibiting an estimated operation, and its operation is inhibited. Subsequently, the controlling circuit 15 and the selecting circuit 14 make a training signal send to the circuit, and also start the estimated operation of the side tone cancelling circuit 18. When the estimated operation has ended, a training end signal is sent out from the selecting circuit 14, and after that, a training start signal from the other station is awaited for a prescribed time, and unless the start signal comes within a prescribed time, it is decided that the other party is not a loud telephone set, a call is executed, and when the start signal comes, a call is started after waiting for incoming of the training end signal.
JP10828580A 1980-08-08 1980-08-08 Echo cancelling device Granted JPS5733843A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10828580A JPS5733843A (en) 1980-08-08 1980-08-08 Echo cancelling device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10828580A JPS5733843A (en) 1980-08-08 1980-08-08 Echo cancelling device

Publications (2)

Publication Number Publication Date
JPS5733843A true JPS5733843A (en) 1982-02-24
JPS6340377B2 JPS6340377B2 (en) 1988-08-10

Family

ID=14480775

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10828580A Granted JPS5733843A (en) 1980-08-08 1980-08-08 Echo cancelling device

Country Status (1)

Country Link
JP (1) JPS5733843A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63160428A (en) * 1986-12-23 1988-07-04 Nec Corp Two-wire voice conference device
JPS63160429A (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
JPH06315176A (en) * 1993-04-30 1994-11-08 Iwatsu Electric Co Ltd Transmission controller

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63160428A (en) * 1986-12-23 1988-07-04 Nec Corp Two-wire voice conference device
JPS63160429A (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
JPH06315176A (en) * 1993-04-30 1994-11-08 Iwatsu Electric Co Ltd Transmission controller
JP2850703B2 (en) * 1993-04-30 1999-01-27 岩崎通信機株式会社 Transmission control device

Also Published As

Publication number Publication date
JPS6340377B2 (en) 1988-08-10

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