[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

FR2452215A1 - Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator - Google Patents

Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator

Info

Publication number
FR2452215A1
FR2452215A1 FR7907109A FR7907109A FR2452215A1 FR 2452215 A1 FR2452215 A1 FR 2452215A1 FR 7907109 A FR7907109 A FR 7907109A FR 7907109 A FR7907109 A FR 7907109A FR 2452215 A1 FR2452215 A1 FR 2452215A1
Authority
FR
France
Prior art keywords
echo
microphone
circuit
reception
comparator
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
FR7907109A
Other languages
French (fr)
Other versions
FR2452215B1 (en
Inventor
Dominique Lajotte
Claude Cardot
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.)
Alcatel CIT SA
Original Assignee
Alcatel CIT SA
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 Alcatel CIT SA filed Critical Alcatel CIT SA
Priority to FR7907109A priority Critical patent/FR2452215A1/en
Publication of FR2452215A1 publication Critical patent/FR2452215A1/en
Application granted granted Critical
Publication of FR2452215B1 publication Critical patent/FR2452215B1/fr
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M9/00—Arrangements for interconnection not involving centralised switching
    • H04M9/08—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic
    • 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

Landscapes

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

Abstract

A subscriber telephone station has a microphone (5) and loud-speaker (6) coupled through respective transmission and reception lines (1,2) and a differential coupler (3) to a telephone connection (4). Two echo suppression circuits suppress respectively the echo transferred electrically by the coupler (3) and acoustically by the microphone and loudspeaker. Each circuit monitors the mean signal power on both lines and controls a respective blocking circuit (7,9) in the transmission line (for acoustic echo) and reception line (for electrical echo), the suppression circuit for the former including a control circuit (8) which multiplies the reception mean signal level by a preset amount and the latter a control circuit (10) which multiplies the transmission mean signal level by the same amount. The control circuits then compare their respective mean signals and control the blocking circuits accordingly.
FR7907109A 1979-03-21 1979-03-21 Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator Granted FR2452215A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR7907109A FR2452215A1 (en) 1979-03-21 1979-03-21 Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7907109A FR2452215A1 (en) 1979-03-21 1979-03-21 Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator

Publications (2)

Publication Number Publication Date
FR2452215A1 true FR2452215A1 (en) 1980-10-17
FR2452215B1 FR2452215B1 (en) 1981-10-23

Family

ID=9223387

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7907109A Granted FR2452215A1 (en) 1979-03-21 1979-03-21 Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator

Country Status (1)

Country Link
FR (1) FR2452215A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4488007A (en) * 1981-12-18 1984-12-11 Thomson-Csf-Telephone Speech-amplifier telephone station
US4549290A (en) * 1983-06-10 1985-10-22 Bell David B Voice/data digital, duplex link
WO2009149737A1 (en) * 2008-06-13 2009-12-17 Sony Ericsson Mobile Communication Ab Method for reducing a disturbance in an input signal caused by an output signal in a multi-port connector, multi-port connector, and mobile device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1542093A (en) * 1966-10-31 1968-10-11 Western Electric Co Device for suppressing echoes in two-way telephone circuits
FR1542092A (en) * 1966-10-31 1968-10-11 Western Electric Co Echo cancellers for long distance telephone circuits
FR2112112A1 (en) * 1970-11-04 1972-06-16 Rusin Marina
US3721777A (en) * 1971-11-26 1973-03-20 Bell Telephone Labor Inc Echo path delay simulator for use with adaptive echo cancellers
FR2195877A1 (en) * 1972-08-10 1974-03-08 Siemens Ag
FR2222544A1 (en) * 1973-03-19 1974-10-18 Honda Motor Co Ltd

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1542093A (en) * 1966-10-31 1968-10-11 Western Electric Co Device for suppressing echoes in two-way telephone circuits
FR1542092A (en) * 1966-10-31 1968-10-11 Western Electric Co Echo cancellers for long distance telephone circuits
FR2112112A1 (en) * 1970-11-04 1972-06-16 Rusin Marina
US3721777A (en) * 1971-11-26 1973-03-20 Bell Telephone Labor Inc Echo path delay simulator for use with adaptive echo cancellers
FR2195877A1 (en) * 1972-08-10 1974-03-08 Siemens Ag
FR2222544A1 (en) * 1973-03-19 1974-10-18 Honda Motor Co Ltd

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4488007A (en) * 1981-12-18 1984-12-11 Thomson-Csf-Telephone Speech-amplifier telephone station
EP0082755B1 (en) * 1981-12-18 1985-10-09 Thomson-Csf Telephone Telephone set with speech amplifiers
US4549290A (en) * 1983-06-10 1985-10-22 Bell David B Voice/data digital, duplex link
WO2009149737A1 (en) * 2008-06-13 2009-12-17 Sony Ericsson Mobile Communication Ab Method for reducing a disturbance in an input signal caused by an output signal in a multi-port connector, multi-port connector, and mobile device

Also Published As

Publication number Publication date
FR2452215B1 (en) 1981-10-23

Similar Documents

Publication Publication Date Title
JP2625301B2 (en) How to improve voice signal quality in telecommunication networks
IE782459L (en) Loudspeaking telephone
GB1470418A (en) Loudspeaking telephone circuit
ES354801A1 (en) Electronic coupler circuit
ES8601604A1 (en) Handsfree circuit for telephone instrument.
JPS6473844A (en) Radio communication equipment
US3769466A (en) Telephone transmission system with echo suppressors
FR2452215A1 (en) Telephone subscriber microphone and loudspeaker unit - suppresses acoustic and electrically transferred echo using comparator
DE2820096A1 (en) Telephone instrument with remote listening unit - uses earphones with radio receiver and transmitter in instrument modulated by speech signal
US3597546A (en) Acoustical coupling system for data communication equipment
US2794857A (en) Control circuit for communications apparatus
US2269565A (en) Communication system
CA2000026A1 (en) Dialing confirmation tone output apparatus
US3872266A (en) Telephone monitor circuit
GB2317535A (en) Loudspeaking telephone systems
JPS561649A (en) Conference telephone equipment
GB1297688A (en)
JPS5553965A (en) Loudspeading simultaneous talking interphone system
JPS5862957A (en) Extension hand free response circuit
JPH0290886A (en) External apparatus interface circuit for key telephone set
JPS6085664A (en) Conference telephone set
JPS6451752A (en) Facsimile equipment
KR830001579B1 (en) 2-wire simultaneous call system of loudspeaker
CA2025071A1 (en) Key telephone system
JPS5635544A (en) Special monitor amplifier

Legal Events

Date Code Title Description
ST Notification of lapse