CA1239712A - Conference circuit for digital communication systems - Google Patents

Conference circuit for digital communication systems

Info

Publication number
CA1239712A
CA1239712A CA000487004A CA487004A CA1239712A CA 1239712 A CA1239712 A CA 1239712A CA 000487004 A CA000487004 A CA 000487004A CA 487004 A CA487004 A CA 487004A CA 1239712 A CA1239712 A CA 1239712A
Authority
CA
Canada
Prior art keywords
sum
conference
samples
conference participants
converter
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.)
Expired
Application number
CA000487004A
Other languages
English (en)
French (fr)
Inventor
Heinrich Kuchler
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.)
Siemens AG
Original Assignee
Siemens AG
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 Siemens AG filed Critical Siemens AG
Application granted granted Critical
Publication of CA1239712A publication Critical patent/CA1239712A/en
Expired legal-status Critical Current

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
    • 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
    • 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
    • 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)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Telephonic Communication Services (AREA)
  • Time-Division Multiplex Systems (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Use Of Switch Circuits For Exchanges And Methods Of Control Of Multiplex Exchanges (AREA)
CA000487004A 1984-07-20 1985-07-18 Conference circuit for digital communication systems Expired CA1239712A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843427303 DE3427303A1 (de) 1984-07-20 1984-07-20 Konferenzschaltung fuer digitale kommunikationssysteme
DEP3427303.4 1984-07-20

Publications (1)

Publication Number Publication Date
CA1239712A true CA1239712A (en) 1988-07-26

Family

ID=6241458

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000487004A Expired CA1239712A (en) 1984-07-20 1985-07-18 Conference circuit for digital communication systems

Country Status (4)

Country Link
US (1) US4635252A (enExample)
JP (1) JPS6139758A (enExample)
CA (1) CA1239712A (enExample)
DE (1) DE3427303A1 (enExample)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0638621B2 (ja) * 1985-03-01 1994-05-18 日本電気株式会社 音声加算分配装置
IT1215490B (it) * 1987-05-14 1990-02-14 Sgs Microelettronica Spa 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.
US4757493A (en) * 1987-06-01 1988-07-12 Motorola Inc. Multi-party telephone conferencing apparatus
JPH01243767A (ja) * 1988-03-25 1989-09-28 Toshiba Corp 会議通話方式
CA2102857C (en) * 1992-12-31 1998-06-23 Alexander Feiner Technique for reducing echoes in conference communications
US5666407A (en) * 1995-12-05 1997-09-09 Ncr Corporation Software-based bridging system for full duplex audio telephone conferencing
DE19815961A1 (de) * 1998-04-09 1999-10-14 Cit Alcatel Elektronische Schaltung zur Mehrkanalverarbeitung von Grundfunktionen
US6944137B1 (en) * 2000-03-24 2005-09-13 Motorola, Inc. Method and apparatus for a talkgroup call in a wireless communication system

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4224688A (en) * 1978-10-30 1980-09-23 Northern Telecom Limited Digital conference circuit
DE2853139A1 (de) * 1978-12-08 1980-06-19 Siemens Ag Transversalfilter
DE3148886C1 (de) * 1981-12-10 1983-08-11 Standard Elektrik Lorenz Ag, 7000 Stuttgart Verfahren und Schaltungsanordnung zum Herstellen einer Konferenzverbindung
US4482998A (en) * 1982-05-27 1984-11-13 At&T Bell Laboratories Method and apparatus for improving the quality of communication in a digital conference arrangement
US4535445A (en) * 1983-06-16 1985-08-13 At&T Information Systems Conferencing system adaptive signal conditioner

Also Published As

Publication number Publication date
US4635252A (en) 1987-01-06
DE3427303A1 (de) 1986-01-30
JPS6139758A (ja) 1986-02-25
DE3427303C2 (enExample) 1988-12-22

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Legal Events

Date Code Title Description
MKEX Expiry