ES8609854A1 - Improvements in telephone instruments - Google Patents

Improvements in telephone instruments

Info

Publication number
ES8609854A1
ES8609854A1 ES544628A ES544628A ES8609854A1 ES 8609854 A1 ES8609854 A1 ES 8609854A1 ES 544628 A ES544628 A ES 544628A ES 544628 A ES544628 A ES 544628A ES 8609854 A1 ES8609854 A1 ES 8609854A1
Authority
ES
Spain
Prior art keywords
paths
telephone instruments
words
hands
comparison
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
ES544628A
Other languages
Spanish (es)
Other versions
ES544628A0 (en
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.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
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 International Standard Electric Corp filed Critical International Standard Electric Corp
Publication of ES544628A0 publication Critical patent/ES544628A0/en
Publication of ES8609854A1 publication Critical patent/ES8609854A1/en
Expired legal-status Critical Current

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
    • H04M9/085—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 digital techniques
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Analogue/Digital Conversion (AREA)
  • Interface Circuits In Exchanges (AREA)

Abstract

In a control circuit for the two speech paths of a hands-free telephone, logarithmic analog to digital converters 133,134 generate digital words corresponding to the signal amplitudes on the two paths. These words are compared with stored references in decision logic and the relative attenuation of the paths is adjusted by switched attenuators 131,132 according to the result of this comparison. The total loop gain is maintained substantially constant.
ES544628A 1984-06-28 1985-06-27 Improvements in telephone instruments Expired ES8609854A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08416415A GB2161047B (en) 1984-06-28 1984-06-28 Improvements in telephone instruments

Publications (2)

Publication Number Publication Date
ES544628A0 ES544628A0 (en) 1986-07-16
ES8609854A1 true ES8609854A1 (en) 1986-07-16

Family

ID=10563086

Family Applications (1)

Application Number Title Priority Date Filing Date
ES544628A Expired ES8609854A1 (en) 1984-06-28 1985-06-27 Improvements in telephone instruments

Country Status (7)

Country Link
JP (1) JPS6115451A (en)
AU (1) AU4346785A (en)
DE (1) DE3522915A1 (en)
ES (1) ES8609854A1 (en)
FR (1) FR2566980A1 (en)
GB (1) GB2161047B (en)
IT (1) IT1206478B (en)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4724540A (en) * 1986-09-02 1988-02-09 Motorola, Inc. Speakerphone with fast idle mode
GB2197166A (en) * 1986-11-07 1988-05-11 Storno As Controlling gain in speech-controlled telephones
EP0290952B1 (en) * 1987-05-15 1992-11-04 Alcatel SEL Aktiengesellschaft Speech control circuitry for a telecommunication terminal
CA1291837C (en) * 1987-07-15 1991-11-05 Juro Ohga Electronic telephone terminal having noise suppression function
US4879745A (en) * 1988-10-12 1989-11-07 Ibm Corporation Half-duplex speakerphone
US5007046A (en) * 1988-12-28 1991-04-09 At&T Bell Laboratories Computer controlled adaptive speakerphone
US4959857A (en) * 1988-12-28 1990-09-25 At&T Bell Laboratories Acoustic calibration arrangement for a voice switched speakerphone
US4901346A (en) * 1988-12-28 1990-02-13 American Telephone And Telegraph Co. Computer controlled speakerphone for adapting to a communication line
US4887288A (en) * 1988-12-28 1989-12-12 American Telephone And Telegraph Company Self calibration arrangement for a voice switched speakerphone
KR920017511A (en) * 1991-02-28 1992-09-26 빈센트 죠셉 로너 Integrated speakerphone circuit and serial port interface for speakerphone
DE4130045A1 (en) * 1991-09-10 1993-03-18 Standard Elektrik Lorenz Ag CIRCUIT ARRANGEMENT FOR THE DYNAMIC CONTROL OF A VOICE TERMINAL
CA2052351C (en) * 1991-09-27 2000-05-23 Gordon J. Reesor Telephone handsfree algorithm
DE4416550C1 (en) * 1994-05-10 1995-09-21 Siemens Ag Loudspeaking telephone terminal circuit with earpiece loudness control
US6978009B1 (en) 1996-08-20 2005-12-20 Legerity, Inc. Microprocessor-controlled full-duplex speakerphone using automatic gain control
JPH10304030A (en) 1997-04-28 1998-11-13 Saitama Nippon Denki Kk Portable telephone system
FR3028375B1 (en) * 2014-11-07 2017-11-24 Euro Prot Surveillance VOICE COMMUNICATION METHOD, AUDIO INTERFACE OF A SOCIAL ALARM SYSTEM, AND SOCIAL ALARM SYSTEM

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA996692A (en) * 1974-12-12 1976-09-07 Russell W. Brown Digital control of a loudspeaking telephone system
DE2651688A1 (en) * 1976-11-12 1978-05-24 Siemens Ag Full-duplex voice-controlled communications system - has voice direction recognition corrected according to noise level using digital circuit
JPS5797262A (en) * 1980-12-09 1982-06-16 Nippon Telegr & Teleph Corp <Ntt> Loud speaker telephone set system
GB2122851B (en) * 1982-06-10 1986-03-19 Standard Telephones Cables Ltd Loudspeaking telephones

Also Published As

Publication number Publication date
ES544628A0 (en) 1986-07-16
GB2161047B (en) 1987-09-16
IT8521356A0 (en) 1985-06-28
GB8416415D0 (en) 1984-08-01
FR2566980A1 (en) 1986-01-03
IT1206478B (en) 1989-04-27
GB2161047A (en) 1986-01-02
DE3522915A1 (en) 1986-01-09
JPS6115451A (en) 1986-01-23
AU4346785A (en) 1986-01-02

Similar Documents

Publication Publication Date Title
ES8609854A1 (en) Improvements in telephone instruments
SE8107354L (en) HOGTALARTELEFONANLEGGNING
AU8001387A (en) Active attenuation system with increased dynamic range
ES2070138T3 (en) HANDS FREE PHONE USING DIGITAL COMPRESSED AUDIO FOR DETECTION OF ACOUSTIC FEEDBACK.
ES8503907A1 (en) Circuit arrangement for a hands free telephone.
EP0129208A3 (en) Handsfree circuit for telephone instrument
FI924027A0 (en) KOPPLINGSARRANGEMANG FOER STYRNING AV DYNAMIK I EN TALAPPARAT.
ES8402684A1 (en) Loudspeaking telephone
DE3167719D1 (en) Telephone circuit
HK32496A (en) Variable gain analog-to-digital conversion apparatus and method
GB1519607A (en) Digital control of a loudspeaking telephone system
JPS56141620A (en) Output error compensating circuit of digital-to-analog converter
ES8400638A1 (en) Adaptive analog-to-digital conversion method and system
ES8800535A1 (en) Sampling rate converter for delta modulated signals.
JPS55128958A (en) Talking system
JPS56156039A (en) Pcm communication system
JPS5735457A (en) Loudspeaker telephone set system
SE7501942L (en)
JPS5624897A (en) Attenuation quantity set system
JPS5678237A (en) Radio telephone set
RU2013004C1 (en) Device for automatic control of analog signals in communication channel
JPS57142063A (en) Audio switch circuit
JPS5765014A (en) Digital control attenuator
JPS6439193A (en) Microphone device
JPS644119A (en) Audio output device