IT1215490B - Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo. - Google Patents

Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo.

Info

Publication number
IT1215490B
IT1215490B IT8720518A IT2051887A IT1215490B IT 1215490 B IT1215490 B IT 1215490B IT 8720518 A IT8720518 A IT 8720518A IT 2051887 A IT2051887 A IT 2051887A IT 1215490 B IT1215490 B IT 1215490B
Authority
IT
Italy
Prior art keywords
telephone
forks
attenuation
called
intended
Prior art date
Application number
IT8720518A
Other languages
English (en)
Other versions
IT8720518A0 (it
Inventor
Angelo Pariani
Francesco Natali
Original Assignee
Sgs Microelettronica Spa
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 Sgs Microelettronica Spa filed Critical Sgs Microelettronica Spa
Priority to IT8720518A priority Critical patent/IT1215490B/it
Publication of IT8720518A0 publication Critical patent/IT8720518A0/it
Priority to DE3850446T priority patent/DE3850446T2/de
Priority to EP88830179A priority patent/EP0291470B1/en
Priority to US07/192,377 priority patent/US4907221A/en
Application granted granted Critical
Publication of IT1215490B publication Critical patent/IT1215490B/it

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/42—Systems providing special services or facilities to subscribers
    • H04M3/56—Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities
    • H04M3/561—Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities by multiplexing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/002—Applications of echo suppressors or cancellers in telephonic connections

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Telephonic Communication Services (AREA)
  • Interconnected Communication Systems, Intercoms, And Interphones (AREA)
IT8720518A 1987-05-14 1987-05-14 Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo. IT1215490B (it)

Priority Applications (4)

Application Number Priority Date Filing Date Title
IT8720518A IT1215490B (it) 1987-05-14 1987-05-14 Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo.
DE3850446T DE3850446T2 (de) 1987-05-14 1988-04-29 Verfahren und Vorrichtung zur Dämpfung des Echosignals in Konferenzgabelschaltungen.
EP88830179A EP0291470B1 (en) 1987-05-14 1988-04-29 A method of attenuating the echo signal in so-called telephone fork converting circuits intended for conference, and an apparatus operating on said method
US07/192,377 US4907221A (en) 1987-05-14 1988-05-10 Apparatus for attenuating the echo signal in telephone fork circuits for telephone conference calls

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT8720518A IT1215490B (it) 1987-05-14 1987-05-14 Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo.

Publications (2)

Publication Number Publication Date
IT8720518A0 IT8720518A0 (it) 1987-05-14
IT1215490B true IT1215490B (it) 1990-02-14

Family

ID=11168142

Family Applications (1)

Application Number Title Priority Date Filing Date
IT8720518A IT1215490B (it) 1987-05-14 1987-05-14 Metodo di attenuazione del segnale di eco in circuiti di conversione, cosiddetti a forchetta telefonica, destinati a conferenze telefoniche, ed apparecchiatura operante secondo tale metodo.

Country Status (4)

Country Link
US (1) US4907221A (it)
EP (1) EP0291470B1 (it)
DE (1) DE3850446T2 (it)
IT (1) IT1215490B (it)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0392061A1 (de) * 1989-04-14 1990-10-17 Siemens Aktiengesellschaft Verfahren zur Herstellung von Konferenzverbindungen in einer digitalen Zeitmultiplex-Fernmeldevermittlungsstelle
EP0836323B1 (en) * 1991-02-20 2004-01-14 Hitachi, Ltd. Television telephone
US5587735A (en) * 1991-07-24 1996-12-24 Hitachi, Ltd. Video telephone
EP0778704A3 (en) * 1991-07-15 1997-08-20 Hitachi Ltd Teleconferencing module
DE69222580T2 (de) 1991-07-15 1998-04-16 Hitachi Ltd Bildkoder-Dekoder und Telekonferenzendstellengerät
JP3308563B2 (ja) * 1991-07-15 2002-07-29 株式会社日立製作所 多地点テレビ会議システム
EP1070417B1 (en) 1998-04-08 2002-09-18 BRITISH TELECOMMUNICATIONS public limited company Echo cancellation
US6895086B2 (en) 2001-11-13 2005-05-17 Inmate Telephone, Inc. 3-Way call detection system and method
US6839417B2 (en) 2002-09-10 2005-01-04 Myriad Entertainment, Inc. Method and apparatus for improved conference call management
AU2004303075B2 (en) * 2003-08-05 2009-06-25 Dsi-Iti, Llc Three-way call detection using steganography
US8542802B2 (en) 2007-02-15 2013-09-24 Global Tel*Link Corporation System and method for three-way call detection
US20080201158A1 (en) * 2007-02-15 2008-08-21 Johnson Mark D System and method for visitation management in a controlled-access environment
US8630726B2 (en) * 2009-02-12 2014-01-14 Value-Added Communications, Inc. System and method for detecting three-way call circumvention attempts
US9225838B2 (en) 2009-02-12 2015-12-29 Value-Added Communications, Inc. System and method for detecting three-way call circumvention attempts
US10572961B2 (en) 2016-03-15 2020-02-25 Global Tel*Link Corporation Detection and prevention of inmate to inmate message relay
US9609121B1 (en) 2016-04-07 2017-03-28 Global Tel*Link Corporation System and method for third party monitoring of voice and video calls
US10027797B1 (en) 2017-05-10 2018-07-17 Global Tel*Link Corporation Alarm control for inmate call monitoring
US10225396B2 (en) 2017-05-18 2019-03-05 Global Tel*Link Corporation Third party monitoring of a activity within a monitoring platform
US10860786B2 (en) 2017-06-01 2020-12-08 Global Tel*Link Corporation System and method for analyzing and investigating communication data from a controlled environment
US9930088B1 (en) 2017-06-22 2018-03-27 Global Tel*Link Corporation Utilizing VoIP codec negotiation during a controlled environment call

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5940341B2 (ja) * 1977-06-29 1984-09-29 株式会社東芝 時分割交換会議システム
US4153817A (en) * 1977-11-25 1979-05-08 Stromberg-Carlson Corporation Digital conference circuit
JPS60253361A (ja) * 1984-05-30 1985-12-14 Fujitsu Ltd 会議通話機能を有する交換システム
DE3427303A1 (de) * 1984-07-20 1986-01-30 Siemens AG, 1000 Berlin und 8000 München Konferenzschaltung fuer digitale kommunikationssysteme

Also Published As

Publication number Publication date
EP0291470A2 (en) 1988-11-17
DE3850446T2 (de) 1994-10-13
DE3850446D1 (de) 1994-08-04
EP0291470B1 (en) 1994-06-29
US4907221A (en) 1990-03-06
EP0291470A3 (en) 1989-08-23
IT8720518A0 (it) 1987-05-14

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Legal Events

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TA Fee payment date (situation as of event date), data collected since 19931001

Effective date: 19970530