JPS59225626A - Echo canceller device for data transmitter - Google Patents

Echo canceller device for data transmitter

Info

Publication number
JPS59225626A
JPS59225626A JP10150783A JP10150783A JPS59225626A JP S59225626 A JPS59225626 A JP S59225626A JP 10150783 A JP10150783 A JP 10150783A JP 10150783 A JP10150783 A JP 10150783A JP S59225626 A JPS59225626 A JP S59225626A
Authority
JP
Japan
Prior art keywords
echo canceller
circuit
signal
echo
attenuation
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.)
Pending
Application number
JP10150783A
Inventor
Hiroyuki Hara
Original Assignee
Nippon Telegr & Teleph Corp <Ntt>
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 Nippon Telegr & Teleph Corp <Ntt> filed Critical Nippon Telegr & Teleph Corp <Ntt>
Priority to JP10150783A priority Critical patent/JPS59225626A/en
Publication of JPS59225626A publication Critical patent/JPS59225626A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B3/00Line transmission systems
    • H04B3/02Details
    • H04B3/20Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
    • H04B3/23Reducing 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
    • H04B3/237Reducing 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 two adaptive filters, e.g. for near end and for end echo cancelling

Abstract

PURPOSE:To decrease the required bit number of an operation processing circuit by combining a processing pre echo canceller and an adaptive type digital processing echo canceller and eliminating a part of an echo signal from an input signal of the latter in advance so as to narrow the dynamic range of an A/D converter. CONSTITUTION:A transmission signal from a transmitter 2 is given a specific frequency characteristic by a filter circuit 22 in a pre echo canceller 21 and attenuated properly by an attenuation circuit 23, then subtracted from a reception signal including an echo signal incoming through a terminal 6 and a hybrid transformer 5 by a subtraction circuit 24. When the frequency characteristic of the filter 22 and the attenuation of the attenuation circuit 23 are decided properly, the absolute amount of the echo signal included in the signal inputted to the digital processing adaptive type echo canceller 13 is decreased, the number of bits required for an A/D converter 7 is reduced and the number of bits of the operation processing circuit is reduced.
JP10150783A 1983-06-06 1983-06-06 Echo canceller device for data transmitter Pending JPS59225626A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10150783A JPS59225626A (en) 1983-06-06 1983-06-06 Echo canceller device for data transmitter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10150783A JPS59225626A (en) 1983-06-06 1983-06-06 Echo canceller device for data transmitter

Publications (1)

Publication Number Publication Date
JPS59225626A true JPS59225626A (en) 1984-12-18

Family

ID=14302503

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10150783A Pending JPS59225626A (en) 1983-06-06 1983-06-06 Echo canceller device for data transmitter

Country Status (1)

Country Link
JP (1) JPS59225626A (en)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0163298A2 (en) * 1984-05-30 1985-12-04 Hitachi, Ltd. PCM coder/decoder with two-wire/four-wire conversion
JPS6266723A (en) * 1985-09-18 1987-03-26 Nec Corp Interference signal eliminating system
JPS62272630A (en) * 1986-05-20 1987-11-26 Nec Corp Echo canceler circuit
JPS62274937A (en) * 1986-05-23 1987-11-28 Nec Corp Echo canceller circuit
JPH01269324A (en) * 1988-04-20 1989-10-26 Fujitsu Ltd Pre echo canceler
EP0596610A2 (en) * 1992-11-02 1994-05-11 Advanced Micro Devices, Inc. Decorrelation controllers for adaptive digital filters
US5511129A (en) * 1990-12-11 1996-04-23 Craven; Peter G. Compensating filters
US6760451B1 (en) 1993-08-03 2004-07-06 Peter Graham Craven Compensating filters
US6895086B2 (en) 2001-11-13 2005-05-17 Inmate Telephone, Inc. 3-Way call detection system and method
US7248685B2 (en) 2003-08-05 2007-07-24 Inmate Telephone, Inc. Three-way call detection using steganography
US8942356B2 (en) 2007-02-15 2015-01-27 Dsi-Iti, Llc System and method for three-way call detection
US9225838B2 (en) 2009-02-12 2015-12-29 Value-Added Communications, Inc. System and method for detecting three-way call circumvention attempts
US9552417B2 (en) 2007-02-15 2017-01-24 Global Tel*Link Corp. System and method for multi-modal audio mining of telephone conversations
US9923936B2 (en) 2016-04-07 2018-03-20 Global Tel*Link Corporation System and method for third party monitoring of voice and video calls
US9930088B1 (en) 2017-06-22 2018-03-27 Global Tel*Link Corporation Utilizing VoIP codec negotiation during a controlled environment call
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
US10572961B2 (en) 2016-03-15 2020-02-25 Global Tel*Link Corporation Detection and prevention of inmate to inmate message relay

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0163298A2 (en) * 1984-05-30 1985-12-04 Hitachi, Ltd. PCM coder/decoder with two-wire/four-wire conversion
JPS6266723A (en) * 1985-09-18 1987-03-26 Nec Corp Interference signal eliminating system
JPS62272630A (en) * 1986-05-20 1987-11-26 Nec Corp Echo canceler circuit
JPS62274937A (en) * 1986-05-23 1987-11-28 Nec Corp Echo canceller circuit
JPH01269324A (en) * 1988-04-20 1989-10-26 Fujitsu Ltd Pre echo canceler
US5815580A (en) * 1990-12-11 1998-09-29 Craven; Peter G. Compensating filters
US5511129A (en) * 1990-12-11 1996-04-23 Craven; Peter G. Compensating filters
US5627899A (en) * 1990-12-11 1997-05-06 Craven; Peter G. Compensating filters
EP0596610A2 (en) * 1992-11-02 1994-05-11 Advanced Micro Devices, Inc. Decorrelation controllers for adaptive digital filters
EP0596610A3 (en) * 1992-11-02 1995-01-04 Advanced Micro Devices Inc Decorrelation controllers for adaptive digital filters.
US5526347A (en) * 1992-11-02 1996-06-11 Advanced Micro Devices, Inc. Decorrelation controller for an adaptive echo cancellor
US6760451B1 (en) 1993-08-03 2004-07-06 Peter Graham Craven Compensating filters
US6895086B2 (en) 2001-11-13 2005-05-17 Inmate Telephone, Inc. 3-Way call detection system and method
US7123704B2 (en) 2001-11-13 2006-10-17 Inmate Telephone, Inc. 3-Way call detection system
US7664243B2 (en) 2001-11-13 2010-02-16 Inmate Telephone, Inc. 3-way call detection system and method
US7248685B2 (en) 2003-08-05 2007-07-24 Inmate Telephone, Inc. Three-way call detection using steganography
US7826604B2 (en) 2003-08-05 2010-11-02 Dsi-Iti, Llc Three-way call detection using steganography
US8942356B2 (en) 2007-02-15 2015-01-27 Dsi-Iti, Llc System and method for three-way call detection
US9552417B2 (en) 2007-02-15 2017-01-24 Global Tel*Link Corp. System and method for multi-modal audio mining of telephone conversations
US9621732B2 (en) 2007-02-15 2017-04-11 Dsi-Iti, Llc System and method for three-way call detection
US10601984B2 (en) 2007-02-15 2020-03-24 Dsi-Iti, Llc System and method for three-way call detection
US9930173B2 (en) 2007-02-15 2018-03-27 Dsi-Iti, Llc System and method for three-way call detection
US10120919B2 (en) 2007-02-15 2018-11-06 Global Tel*Link Corporation System and method for multi-modal audio mining of telephone conversations
US9225838B2 (en) 2009-02-12 2015-12-29 Value-Added Communications, Inc. System and method for detecting three-way call circumvention attempts
US10057398B2 (en) 2009-02-12 2018-08-21 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
US9923936B2 (en) 2016-04-07 2018-03-20 Global Tel*Link Corporation System and method for third party monitoring of voice and video calls
US10277640B2 (en) 2016-04-07 2019-04-30 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
US10601982B2 (en) 2017-05-18 2020-03-24 Global Tel*Link Corporation Third party monitoring of activity within a monitoring platform
US9930088B1 (en) 2017-06-22 2018-03-27 Global Tel*Link Corporation Utilizing VoIP codec negotiation during a controlled environment call
US10693934B2 (en) 2017-06-22 2020-06-23 Global Tel*Link Corporation Utilizing VoIP coded negotiation during a controlled environment call

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