FI88570B - Telefonkrets som laemnar haenderna fria - Google Patents

Telefonkrets som laemnar haenderna fria Download PDF

Info

Publication number
FI88570B
FI88570B FI863169A FI863169A FI88570B FI 88570 B FI88570 B FI 88570B FI 863169 A FI863169 A FI 863169A FI 863169 A FI863169 A FI 863169A FI 88570 B FI88570 B FI 88570B
Authority
FI
Finland
Prior art keywords
signal
modified
adaptive filter
hands
echo
Prior art date
Application number
FI863169A
Other languages
English (en)
Finnish (fi)
Other versions
FI863169A0 (fi
FI88570C (sv
FI863169A7 (fi
Inventor
Larry C Puhl
Richard J Vilmur
Original Assignee
Motorola 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 Motorola Inc filed Critical Motorola Inc
Publication of FI863169A0 publication Critical patent/FI863169A0/fi
Publication of FI863169A7 publication Critical patent/FI863169A7/fi
Publication of FI88570B publication Critical patent/FI88570B/fi
Application granted granted Critical
Publication of FI88570C publication Critical patent/FI88570C/sv

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
    • H04M9/082—Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic using 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
  • Telephone Function (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Inks, Pencil-Leads, Or Crayons (AREA)
  • Measurement Of Unknown Time Intervals (AREA)
  • Time Recorders, Dirve Recorders, Access Control (AREA)
  • Near-Field Transmission Systems (AREA)
  • Transceivers (AREA)
  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)

Claims (7)

1. Telefonkrets, som lämnar händerna fria och upphäver oönskad signalkoppling, omfattande en hög- 5 talare (113), som omformar en modifierad första signal erhällen frän en första signal mottagen frän en kommu- nikationskanal, och en mikrofon (115), som omformar en andra för omformning och överföring som en modifierad andra signal pa en kommunikationskanal samtidigt med 10 den första signalen, kännetecknad därav, att ett detektororgan (225) för den modifierade första signalen; ett första anpassningsfilter (301) med koeffi-cientbestämmande organ styrt av nämnda detektororgan för den modifierade första signalen; organ omfattande 15 nämnda första anpassningsfilter (301) för substration (303) av ätminstone en del av den modifierade första signalen frAn den andra signalen, därvid ästadkommande den modifierade andra signalen med kopplingen frän den modifierade första signalen väsentligen upphävd; ett 20 detektororgan (223) för den modifierade andra signalen; ett andra anpassningsfilter (305) med koefficientbe-stämmande organ styrt av nämnda detektororgan för den nämnda modifierade andra signalen; och organ omfattande nämnda andra anpassningsfilter (305) för subtraktion 25 (307) av ätminstone en del av den modifierade andra signalen frän den första signalen, därvid ästadkommande den modifierade första signalen med kopplingen frän den modifierade andra signalen väsentligen upphävd.
2. Telefonkrets, som lämnar händerna fria, 30 enligt patentkravet 1, ytterligare känneteck-n a d därav, att ett niväsänkande organ (604) för den modifierade första signalen och ett niväsänkande organ (609) för den modifierade andra signalen, kopplat tili respektive nämnda detektor (225) för den modifierade 35 första signalen och nämnda detektor (223) för den modi- i 23 88570 fierade andra signalen, sä att bäda de niväsänkande organen aktiveras, dä den modifierade första signalen och den modifierade andra signalen samtidigt detekteras.
3. Telefonkrets, som lämnar händerna fria, 5 enligt patentkravet 1, ytterligare känneteck-n a d av ett organ (501) kopplat till nämnda sub-traktionsorgan (303) för den modifierade första signalen för att kompensera nämnda del av den modifierade första signalen för alineariteter, som högtalaren (113) inför 10. den modifierade första signalen.
4. Telefonkrets, som lämnar händerna fria, enligt patentkravet 1, ytterligare känneteck-n a d av ett organ (503) kopplat till nämnda sub-traktionsorgan (307) för den modifierade andra signalen 15 för att kompensera nämnda del av den modifierade andra signalen för alineariteter införda i den modifierade andra signalen av kommunikationskanalerna.
5. Telefonkrets, som lämnar händerna fria, enligt patentkravet 1, väri nämnda detektororgan (225) 20 för den modifierade första signalen och nämnda detektororgan (223) för den modifierade andra signalen vardera ytterligare kännetecknad av organ för detektering (229) och filtrering (230) av den modifierade första signalens envelopp; organ för 25 dynamisk detektering (231) av den modifierade första signalens minima; och organ för jämförelse (235) av den detekterade och filtrerade enveloppen med de detekterade minima och ästadkommande en utgangssignal ....: vid detektering av den första signalen, da den modi- . 30 fierade första signalens envelopp överskrider minima med en förutbestämd mängd. 24 88570
6. Telefonkrets, som lämnar händerna fria, enligt patentkravet 1, ytterligare kännetecknad av ett nivähöjande organ (604) för den av en högtalare (113) omformade första signalen, dä den modifierade 5 första signalen är detekterad.
7. Telefonkrets, som lämnar händerna fria, enligt patentkravet 1, ytterligare kännetecknad av ett nivähöjande organ (609) för den modifierade 10 andra signalen, som överförs av sändaren, dä den modifierade andra signalen är detekterad. i
FI863169A 1984-12-14 1986-08-04 Telefonkrets som lämnar händerna fria FI88570C (sv)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US06/681,540 US4629829A (en) 1984-12-14 1984-12-14 Full duplex speakerphone for radio and landline telephones
US68154084 1984-12-14
PCT/US1985/002050 WO1986003912A1 (en) 1984-12-14 1985-10-16 Full duplex speakerphone for radio and landline telephones
US8502050 1985-10-16

Publications (4)

Publication Number Publication Date
FI863169A0 FI863169A0 (fi) 1986-08-04
FI863169A7 FI863169A7 (fi) 1986-08-04
FI88570B true FI88570B (fi) 1993-02-15
FI88570C FI88570C (sv) 1993-05-25

Family

ID=24735704

Family Applications (1)

Application Number Title Priority Date Filing Date
FI863169A FI88570C (sv) 1984-12-14 1986-08-04 Telefonkrets som lämnar händerna fria

Country Status (13)

Country Link
US (1) US4629829A (sv)
EP (1) EP0204718B2 (sv)
JP (1) JPS61502581A (sv)
KR (1) KR930007740Y1 (sv)
CN (1) CN1003555B (sv)
AT (1) ATE73276T1 (sv)
AU (1) AU574983B2 (sv)
CA (1) CA1234235A (sv)
DE (1) DE3585532D1 (sv)
DK (1) DK385486D0 (sv)
FI (1) FI88570C (sv)
NO (1) NO301859B1 (sv)
WO (1) WO1986003912A1 (sv)

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Also Published As

Publication number Publication date
CN85109020A (zh) 1986-11-19
FI863169A0 (fi) 1986-08-04
JPS61502581A (ja) 1986-11-06
DK385486A (da) 1986-08-13
AU5018185A (en) 1986-07-22
US4629829A (en) 1986-12-16
EP0204718B1 (en) 1992-03-04
ATE73276T1 (de) 1992-03-15
EP0204718B2 (en) 1998-04-22
NO301859B1 (no) 1997-12-15
CA1234235A (en) 1988-03-15
JPH0511687B2 (sv) 1993-02-16
CN1003555B (zh) 1989-03-08
NO863275L (no) 1986-08-22
EP0204718A4 (en) 1988-03-30
AU574983B2 (en) 1988-07-14
KR930007740Y1 (en) 1993-11-17
NO863275D0 (no) 1986-08-14
FI88570C (sv) 1993-05-25
DE3585532D1 (de) 1992-04-09
FI863169A7 (fi) 1986-08-04
DK385486D0 (da) 1986-08-13
WO1986003912A1 (en) 1986-07-03
EP0204718A1 (en) 1986-12-17

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