FI74560B - Ekoborttagningsanordning. - Google Patents

Ekoborttagningsanordning. Download PDF

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Publication number
FI74560B
FI74560B FI823967A FI823967A FI74560B FI 74560 B FI74560 B FI 74560B FI 823967 A FI823967 A FI 823967A FI 823967 A FI823967 A FI 823967A FI 74560 B FI74560 B FI 74560B
Authority
FI
Finland
Prior art keywords
signal
output
sampling
path
information
Prior art date
Application number
FI823967A
Other languages
English (en)
Finnish (fi)
Other versions
FI823967A0 (fi
FI74560C (sv
FI823967L (fi
Inventor
David Anthony Fisher
Original Assignee
Stc Plc
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 Stc Plc filed Critical Stc Plc
Publication of FI823967A0 publication Critical patent/FI823967A0/fi
Publication of FI823967L publication Critical patent/FI823967L/fi
Publication of FI74560B publication Critical patent/FI74560B/fi
Application granted granted Critical
Publication of FI74560C publication Critical patent/FI74560C/sv

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
    • H04L25/03006—Arrangements for removing intersymbol interference
    • H04L25/03012—Arrangements for removing intersymbol interference operating in the time domain
    • H04L25/03019—Arrangements for removing intersymbol interference operating in the time domain adaptive, i.e. capable of adjustment during data reception
    • H04L25/03057—Arrangements for removing intersymbol interference operating in the time domain adaptive, i.e. capable of adjustment during data reception with a recursive structure
    • 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
    • H04B3/235—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 combined with adaptive equaliser

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Filters That Use Time-Delay Elements (AREA)
  • Interface Circuits In Exchanges (AREA)
  • Networks Using Active Elements (AREA)

Claims (4)

1. Digital transmissionsstation för användning i ett system, väri digital information transporteras an-5 tingen i en eller tvA riktningar längs en transmissions-bana, varvid stationen inkluderar GA- och RETUR-banor kopplade till transmissionsbanan via en hybrid (4) eller dess ekvivalent, varvid GA-banan inkluderar en kodare (2), som kodar informationen som skall överföras till ett for-10 mat, som är lämpligt för transmission längs nämnda ena transmissionsbana före informationen mätäs tili hybriden (4) eller dess ekvivalent, varvid den pA RETUR-banan mot-tagna informationen mätäs tili en analog-digitalomvandla-re (8), som producerar en utgAng för varje mottaget in-15 formationstecken av informationen, som mottagits via hybriden (4) eller dess ekvivalent, vilken utgAng har ett digitalt format som betecknar signalvärdet vid ett speci-fikt samplingsögonblick, varvid utgAngen frAn omvandlaren (8) är matad tili ena ingAngen i en subtraktionskrets (9), 20 varvid informationen som matats pA detta sätt tili följd av bristfällighet i hybriden (4) eller dess ekvivalent inkluderar en icke Önskvärd signal, varvid kodarens (2) utgAng pA GA-banan är matad via en ekosimulator tili sub-traktionskretsens (9) andra ingAng pA RETUR-banan sA, att 25 nämnda andra ingAng mottager en version av en signal pA GA-banan, vilken version subtraheras frAn informationen pA RETUR-banan sA, att subtraktionskretsens (9) utgAng är en version av den mottagna signalen, frAn vilken den icke önskade signalen är väsentligen avlägsnad, varvid subtrak-30 tionskretsens (9) utgAng är matad via en adaptiv valAter-kopplingsekvalisator (14) tili en dekoder (17), som utför omvända operationer av de operationer som kodaren (2) ut-fört pA GA-banan, varvid subtraktionskretsens (9) utgAng är matad tillbaka tili ekosimulatorn (12) sA att amplitu-35 den av den frAn ekosimulatorn (12) tili subtraktionskret- ? 8 74560 sen (9) kommande ingängen härvid regleras för att den icke önskade signalen skall vara väsentligen avlägsnad . frän subtraktionskretsens utgäng, känneteck-n a d därav, att informationen pä RETUR-banan kontinuer-5 ligt samplas pä informationsbitsfrekvensen med en samplings- och hällarkrets (13); att nämnda sampling är ut-förd under styrning av en extraktionskontrollkrets (15) för tidsinställning, vilken styrning övervakar informationen i nämnda ekvalisator (14); att styrkretsen (16) för 10 samplingstiden under styrning av kontrollkretsen (15) ästadkommer en signal för varje samplingsoperation under användande av en fastläst slinga, vilken päverkas av kontrollkretsens (15) utgäng; att styrningen för nämnda slinga även innehäller en multiplikator (35), som opere-15 rar pä värdena för kursorns koefficientvärde (C ) samt valvärdet (D^), vilka värden har letts frän det rädande tecknet; och att slingans styrning även inkluderar en skalarkrets (36), som opererar p& en felsignal (e^) pro-ducerad av en subtraktionskrets (37) tili vilken värdena 20 för det rädande tecknet och multiplikatorn (35) är matade.
2. Station enligt patentkravet 1, väri ekoupphäva-ren fungerar genom att tillsätta i signalen, som löper genom den en mängd vända koefficienter, vilka styr ästad-kommandet av en version av GA-banans signal för matning 25 tili subtraktionskretsen (9), kännetecknad därav, att nämnda koefficienter har frambringats medelst multipleksorer (90, 91, 92) via vilka de ackumulatorer, som använts för att frambringa dessa koefficienter kan vara korskopplade sä, att alla koefficienter kan förskju-30 tas främät eller bakät ett steg; och att nämnda förskjut-ning framät eller bakät tillsammans med ett klockalst-ringsmedel tilläter ekoupphävningsfunktionerna utan dis-kontinuitet att spära en kontinuerlig frekvensdifferens mellan den lokala samplingsklockan och sändarklockan, vil-35 ken differens förekommer dä ekosimulatorns klocka inte är läst vid den lokala sändarens klocka. Il
FI823967A 1981-11-19 1982-11-18 Ekoborttagningsanordning. FI74560C (sv)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB08134898A GB2111354B (en) 1981-11-19 1981-11-19 Echo canceller
GB8134898 1981-11-19

Publications (4)

Publication Number Publication Date
FI823967A0 FI823967A0 (fi) 1982-11-18
FI823967L FI823967L (fi) 1983-05-20
FI74560B true FI74560B (fi) 1987-10-30
FI74560C FI74560C (sv) 1988-02-08

Family

ID=10526000

Family Applications (1)

Application Number Title Priority Date Filing Date
FI823967A FI74560C (sv) 1981-11-19 1982-11-18 Ekoborttagningsanordning.

Country Status (12)

Country Link
US (1) US4539675A (sv)
EP (1) EP0096048B1 (sv)
BE (1) BE895066R (sv)
CA (1) CA1210471A (sv)
DE (2) DE3272474D1 (sv)
ES (1) ES8402128A1 (sv)
FI (1) FI74560C (sv)
GB (1) GB2111354B (sv)
NL (1) NL8204483A (sv)
NO (1) NO161098C (sv)
SE (1) SE8206608D0 (sv)
WO (1) WO1983001876A1 (sv)

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DE3327467A1 (de) * 1983-07-29 1985-02-14 Siemens AG, 1000 Berlin und 8000 München Verfahren und schaltungsanordnung zur kompensation von echosignalen
EP0139814A3 (de) * 1983-09-30 1986-07-30 Siemens-Albis Aktiengesellschaft Aktive Entzerrerschaltung
IT1178913B (it) * 1984-03-26 1987-09-16 Cselt Centro Studi Lab Telecom Sistema per la trassmissione bidire zionale con cancellazione d eco
EP0156315B1 (de) * 1984-03-30 1991-06-05 Siemens Aktiengesellschaft Schaltungsanordnung zum Prüfen der Funktionsfähigkeit einer Datenübertragunseinrichtung
EP0167677B1 (en) * 1984-07-13 1989-03-08 BELL TELEPHONE MANUFACTURING COMPANY Naamloze Vennootschap Signal processing arrangement
US4650930A (en) * 1985-02-13 1987-03-17 Northern Telecom Limited Adaptive equalizer
SE447777B (sv) * 1985-04-22 1986-12-08 Ellemtel Utvecklings Ab Forfarande for instellning av ett digitalt utjemnarfilter vid samtidig adaptiv ekoeliminering och adaptiv eliminering av storningar som uppstar genom intersymbolinterferens, samt anordning for genomforande av forfarande
GB2182826B (en) * 1985-11-20 1990-08-01 Stc Plc Data transmission system
GB2183971B (en) * 1985-12-05 1989-10-04 Stc Plc Data transmission system
EP0239293A3 (en) * 1986-03-24 1988-12-14 Gpt Limited Data transmission systems
US4809203A (en) * 1986-08-25 1989-02-28 Ford Aerospace & Communications Corporation Hybrid analog-digital filter
NL8603247A (nl) * 1986-12-22 1988-07-18 At & T & Philips Telecomm Adaptief tijd-discreet filter voor het vormen van een compensatiesignaal uit synchrone datasymbolen.
FR2614484B1 (fr) * 1986-12-30 1994-04-08 Telecommunications Sa Terminal de transmission de donnees sur une voie analogique bidirectionnelle avec annulation d'echo couplee au rythme reception
US4989221A (en) * 1987-03-30 1991-01-29 Codex Corporation Sample rate converter
US4982428A (en) * 1988-12-29 1991-01-01 At&T Bell Laboratories Arrangement for canceling interference in transmission systems
US5125024A (en) * 1990-03-28 1992-06-23 At&T Bell Laboratories Voice response unit
US5263019A (en) * 1991-01-04 1993-11-16 Picturetel Corporation Method and apparatus for estimating the level of acoustic feedback between a loudspeaker and microphone
FR2710211A1 (fr) * 1993-09-13 1995-03-24 Trt Telecom Radio Electr Dispositif de détection de rupture de ligne et modem comportant un tel dispositif.
US5471527A (en) 1993-12-02 1995-11-28 Dsc Communications Corporation Voice enhancement system and method
US5627885A (en) * 1994-02-14 1997-05-06 Brooktree Corporation System for, and method of, transmitting and receiving through telephone lines signals representing data
US5887059A (en) * 1996-01-30 1999-03-23 Advanced Micro Devices, Inc. System and method for performing echo cancellation in a communications network employing a mixed mode LMS adaptive balance filter
US5889827A (en) * 1996-12-12 1999-03-30 Ericsson Inc. Method and apparatus for digital symbol detection using medium response estimates
US6597732B1 (en) * 1999-01-14 2003-07-22 Eric Morgan Dowling High-speed modem with uplink remote-echo canceller
US6341360B1 (en) * 1999-03-08 2002-01-22 International Business Machines Corporation Decision feedback equalizers, methods, and computer program products for detecting severe error events and preserving equalizer filter characteristics in response thereto
US7003030B2 (en) 1999-03-08 2006-02-21 Lenovo (Singapore) Pte. Ltd. Receivers, methods, and computer program products for an analog modem that receives data signals from a digital modem
US6487243B1 (en) 1999-03-08 2002-11-26 International Business Machines Corporation Modems, methods, and computer program products for recovering from errors in a tone reversal sequence between two modems
US6661837B1 (en) 1999-03-08 2003-12-09 International Business Machines Corporation Modems, methods, and computer program products for selecting an optimum data rate using error signals representing the difference between the output of an equalizer and the output of a slicer or detector
US6389064B1 (en) * 1999-03-08 2002-05-14 International Business Machines Corporation Modems, methods, and computer program products for identifying a signaling alphabet in variance with an ideal alphabet due to digital impairments
US6381267B1 (en) 1999-03-08 2002-04-30 International Business Machines Corporation Modems, methods, and computer program products for falling back to a lower data rate protocol upon detecting abnormal line conditions during startup
US6553518B1 (en) 1999-03-08 2003-04-22 International Business Machines Corporation Severe error detectors, methods and computer program products that use constellation specific error event thresholds to detect severe error events during demodulation of a signal comprising symbols from a plurality of symbol constellations
US6816100B1 (en) 1999-03-12 2004-11-09 The Regents Of The University Of California Analog-to-digital converters with common-mode rejection dynamic element matching, including as used in delta-sigma modulators
US6661847B1 (en) 1999-05-20 2003-12-09 International Business Machines Corporation Systems methods and computer program products for generating and optimizing signal constellations
GB2362063A (en) * 2000-04-25 2001-11-07 Mitel Corp Connecting broadband voice and data signals to telephone systems
US7190718B2 (en) * 2002-07-17 2007-03-13 Broadcom Corporation Method and apparatus for determining a receiver sampling phase for use in diagnosing a channel
US7239680B2 (en) * 2002-07-17 2007-07-03 Broadcom Corporation Methods for performing channel diagnostics
US7251213B2 (en) * 2002-09-17 2007-07-31 At&T Corp. Method for remote measurement of echo path delay
US7440499B2 (en) * 2004-01-29 2008-10-21 Infineon Technologies Ag Fractional spaced equalizer
DE102004025576B4 (de) * 2004-05-25 2006-03-30 Infineon Technologies Ag Sende-und Empfangsanordnung mit einer Regelung zur Störsignalunterdrückung
EP1796281B1 (en) * 2005-12-09 2015-08-12 Mitel Networks Corporation Echo canceller
JP4771532B2 (ja) * 2006-02-01 2011-09-14 オンセミコンダクター・トレーディング・リミテッド エコー防止回路及びデジタル信号処理回路
US8331430B2 (en) * 2006-08-02 2012-12-11 Broadcom Corporation Channel diagnostic systems and methods
CN103557753B (zh) * 2013-10-24 2015-05-27 北京理工大学 一种激光回波模拟装置及方法

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NL170688C (nl) * 1976-06-28 1982-12-01 Philips Nv Inrichting voor simultane tweerichtingsdatatransmissie over tweedraadsverbindingen.
JPS5617532A (en) * 1979-07-20 1981-02-19 Nec Corp Automatic equalizer

Also Published As

Publication number Publication date
DE3272474D1 (en) 1986-09-11
CA1210471A (en) 1986-08-26
NO161098B (no) 1989-03-20
WO1983001876A1 (en) 1983-05-26
FI823967A0 (fi) 1982-11-18
GB2111354A (en) 1983-06-29
GB2111354B (en) 1985-06-19
EP0096048B1 (en) 1986-08-06
EP0096048A1 (en) 1983-12-21
NL8204483A (nl) 1983-06-16
FI74560C (sv) 1988-02-08
DE3242577A1 (de) 1983-05-26
ES517479A0 (es) 1984-01-16
ES8402128A1 (es) 1984-01-16
US4539675A (en) 1985-09-03
NO823856L (no) 1983-05-20
FI823967L (fi) 1983-05-20
SE8206608D0 (sv) 1982-11-19
BE895066R (fr) 1983-05-19
NO161098C (no) 1989-06-28

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Owner name: STC PLC