FR2366750A1 - Circuit d'elimination d'echos - Google Patents

Circuit d'elimination d'echos

Info

Publication number
FR2366750A1
FR2366750A1 FR7729794A FR7729794A FR2366750A1 FR 2366750 A1 FR2366750 A1 FR 2366750A1 FR 7729794 A FR7729794 A FR 7729794A FR 7729794 A FR7729794 A FR 7729794A FR 2366750 A1 FR2366750 A1 FR 2366750A1
Authority
FR
France
Prior art keywords
circuit
echo elimination
input
output
elimination 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.)
Granted
Application number
FR7729794A
Other languages
English (en)
Other versions
FR2366750B1 (fr
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.)
AT&T Corp
Original Assignee
Western Electric Co Inc
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 Western Electric Co Inc filed Critical Western Electric Co Inc
Publication of FR2366750A1 publication Critical patent/FR2366750A1/fr
Application granted granted Critical
Publication of FR2366750B1 publication Critical patent/FR2366750B1/fr
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
    • H04B3/232—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 phase shift, phase roll or frequency offset correction

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

L'invention concerne un circuit d'élimination d'échos dans une ligne de transmission, et plus particulièrement des déphaseurs de phase variables pour de tels circuits d'élimination d'échos. L'invention réside dans le fait que le circuit comprend un circuit d'élimination d'échos 123 dont une entrée est connectée au circuit d'entrée 112 par l'intermédiaire d'un circuit à déphasage variable 122 et d'un convertisseur 118 et dont l'autre entrée est connectée au circuit de sortie 113. Le signal de sortie du circuit 123 est comparé dans un circuit 129 au signal de sortie du circuit 113 de manière à fournir un signal de commande du circuit 122 qui reçoit par ailleurs le signal de sortie du circuit 123. L'invention est applicable aux lignes de transmission en téléphonie.
FR7729794A 1976-10-04 1977-10-04 Circuit d'elimination d'echos Granted FR2366750A1 (fr)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US05/729,004 US4072830A (en) 1976-10-04 1976-10-04 Variable phase shifter for adaptive echo cancellers

Publications (2)

Publication Number Publication Date
FR2366750A1 true FR2366750A1 (fr) 1978-04-28
FR2366750B1 FR2366750B1 (fr) 1981-07-17

Family

ID=24929178

Family Applications (1)

Application Number Title Priority Date Filing Date
FR7729794A Granted FR2366750A1 (fr) 1976-10-04 1977-10-04 Circuit d'elimination d'echos

Country Status (8)

Country Link
US (1) US4072830A (fr)
JP (1) JPS5824053B2 (fr)
AU (1) AU508799B2 (fr)
CA (1) CA1096005A (fr)
DE (1) DE2744600A1 (fr)
FR (1) FR2366750A1 (fr)
GB (1) GB1586210A (fr)
NL (1) NL7710592A (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2435172A1 (fr) * 1978-08-29 1980-03-28 Cselt Centro Studi Lab Telecom Procede et dispositif permettant d'annuler les echos dans les lignes telephoniques

Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1091970B (it) * 1977-01-17 1985-07-06 Trt Telecom Radio Electr Dispositivo digitale per la cancellazione di echi,per un modulatore/demodulatore,per la trasmissione di dati mediante modulazione di una portante
US4129753A (en) * 1977-12-09 1978-12-12 Bell Telephone Laboratories, Incorporated Echo canceller using feedback to improve speech detector performance
US4320498A (en) * 1980-02-11 1982-03-16 Apple Computer, Inc. Auto balancing duplexer for communication lines
FR2487144B1 (fr) * 1980-07-21 1986-10-24 Trt Telecom Radio Electr Dispositif d'annulation d'un signal d'echo composite
US4381561A (en) * 1980-10-23 1983-04-26 International Telephone And Telegraph Corporation All digital LSI line circuit for analog lines
US4351060A (en) * 1980-10-23 1982-09-21 International Telephone And Telegraph Corporation Automatic, digitally synthesized matching line terminating impedance
US4491701A (en) * 1981-03-05 1985-01-01 At&T Bell Laboratories Adaptive filter including a far end energy discriminator
US4405840A (en) * 1981-03-05 1983-09-20 Bell Telephone Laboratories, Incorporated Echo canceler far end energy discriminator
WO1982003144A1 (fr) * 1981-03-05 1982-09-16 Western Electric Co Discriminateur de bandes d'energie
US4375692A (en) * 1981-04-30 1983-03-01 The United States Of America As Represented By The Secretary Of The Navy Least squares lattice decision feedback equalizer
FR2509552A1 (fr) * 1981-07-09 1983-01-14 Telecommunications Sa Dispositif de compensation de phase d'echo et son application aux annulateurs d'echo
DE3327467A1 (de) * 1983-07-29 1985-02-14 Siemens AG, 1000 Berlin und 8000 München Verfahren und schaltungsanordnung zur kompensation von echosignalen
GB2144950A (en) * 1983-08-10 1985-03-13 Philips Electronic Associated Data transmission system
US4682358A (en) * 1984-12-04 1987-07-21 American Telephone And Telegraph Company Echo canceller
NZ214905A (en) * 1985-01-29 1988-09-29 British Telecomm Noise cancellation by adaptive filter compensates for timing variations
JPH0720070B2 (ja) * 1985-08-14 1995-03-06 株式会社日立製作所 デイジタル平衡回路を有するｐｃｍ符号復号器
US4811342A (en) * 1985-11-12 1989-03-07 Racal Data Communications Inc. High speed analog echo canceller
JPH0616592B2 (ja) * 1985-12-23 1994-03-02 富士通株式会社 Ｆｄｍモデム
GB8625282D0 (en) * 1986-10-22 1986-11-26 British Telecomm Detecting faults in transmission lines
US4813073A (en) * 1987-07-02 1989-03-14 Codex Corporation Echo cancellation
FR2629293A1 (fr) * 1988-03-25 1989-09-29 Trt Telecom Radio Electr Annuleur d'echo pour signal d'echo a phase variable
US5001747A (en) * 1990-01-22 1991-03-19 Racal Data Communications Inc. Frequency offset estimator for data modem
US5280473A (en) * 1990-02-08 1994-01-18 Universal Data Systems, Inc. Modem with echo cancellation
US5471527A (en) 1993-12-02 1995-11-28 Dsc Communications Corporation Voice enhancement system and method
US20030109282A1 (en) * 2001-12-06 2003-06-12 Itzhak Shperling Method and base station for providing phase-shift transmit diversity
GB2396279A (en) * 2002-12-09 2004-06-16 Acuid Corp Simultaneous bidirectional differential signalling interface with echo cancellation
US7702004B2 (en) * 2002-12-09 2010-04-20 Alexander Roger Deas Simultaneous bidirectional differential signalling interface
US11239985B2 (en) * 2019-04-16 2022-02-01 Cisco Technology, Inc. Echo cancellation in multiple port full duplex (FDX) nodes and amplifiers

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3597541A (en) * 1969-12-23 1971-08-03 Sylvania Electric Prod Decision-directed adapted equalizer circuit
US3721777A (en) * 1971-11-26 1973-03-20 Bell Telephone Labor Inc Echo path delay simulator for use with adaptive echo cancellers

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2435172A1 (fr) * 1978-08-29 1980-03-28 Cselt Centro Studi Lab Telecom Procede et dispositif permettant d'annuler les echos dans les lignes telephoniques

Also Published As

Publication number Publication date
GB1586210A (en) 1981-03-18
CA1096005A (fr) 1981-02-17
JPS5345919A (en) 1978-04-25
NL7710592A (nl) 1978-04-06
DE2744600C2 (fr) 1988-07-28
AU508799B2 (en) 1980-04-03
JPS5824053B2 (ja) 1983-05-19
US4072830A (en) 1978-02-07
DE2744600A1 (de) 1978-04-06
FR2366750B1 (fr) 1981-07-17
AU2919777A (en) 1979-04-05

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Legal Events

Date Code Title Description
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