JPS62159925A - Echo eliminating device - Google Patents

Echo eliminating device

Info

Publication number
JPS62159925A
JPS62159925A JP245486A JP245486A JPS62159925A JP S62159925 A JPS62159925 A JP S62159925A JP 245486 A JP245486 A JP 245486A JP 245486 A JP245486 A JP 245486A JP S62159925 A JPS62159925 A JP S62159925A
Authority
JP
Japan
Prior art keywords
coding
differential
echo
value
adaptive filters
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
JP245486A
Other languages
Japanese (ja)
Inventor
Akira Kanemasa
Original Assignee
Nec 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 Nec Corp filed Critical Nec Corp
Priority to JP245486A priority Critical patent/JPS62159925A/en
Publication of JPS62159925A publication Critical patent/JPS62159925A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE: To eliminate the echo with small hardware scale by providing two adaptive filters generating an echo replica from a differential code being the result of differential coding to a binary-coding data to be sent and obtaining the sum of the two echo replicas obtained in this way.
CONSTITUTION: A differential coding circuit 16 consists of a modulo 2 operating element 17 and a delay element 18 having a delay of Tsec (T is a period of transmission data) and applies differential coding to the original binary-coding data. The adaptive filters 9, 10 act like eliminating the echo caused by the symmetrical and asymmetrical component of bipolar pulses, the filter 9 uses the said differential coding result to regard the AMI coding equivalent as di- pulse coding and is operated. Further, the adaptive filter 10 inputs an AND between a 1-bit preceding value of the differential code and the inverted value of the present value by means of an AND element 19 and an inverter 20 and is operated. Then number of taps for the adaptive filters 9, 10 is both decreased and only one kind of each tap coefficient is enough, then the entire hardware scale is reduced.
COPYRIGHT: (C)1987,JPO&Japio
JP245486A 1986-01-09 1986-01-09 Echo eliminating device Pending JPS62159925A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP245486A JPS62159925A (en) 1986-01-09 1986-01-09 Echo eliminating device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP245486A JPS62159925A (en) 1986-01-09 1986-01-09 Echo eliminating device

Publications (1)

Publication Number Publication Date
JPS62159925A true JPS62159925A (en) 1987-07-15

Family

ID=11529736

Family Applications (1)

Application Number Title Priority Date Filing Date
JP245486A Pending JPS62159925A (en) 1986-01-09 1986-01-09 Echo eliminating device

Country Status (1)

Country Link
JP (1) JPS62159925A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6655250B1 (en) 1999-05-13 2003-12-02 Yamaha Corporation Punching apparatus
WO2005057804A1 (en) * 2003-12-10 2005-06-23 Koninklijke Philips Electronics N.V. Echo canceller having a series arrangement of adaptive filters with individual update control strategy
US7280060B1 (en) 2000-05-23 2007-10-09 Marvell International Ltd. Communication driver

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6655250B1 (en) 1999-05-13 2003-12-02 Yamaha Corporation Punching apparatus
US7280060B1 (en) 2000-05-23 2007-10-09 Marvell International Ltd. Communication driver
WO2005057804A1 (en) * 2003-12-10 2005-06-23 Koninklijke Philips Electronics N.V. Echo canceller having a series arrangement of adaptive filters with individual update control strategy

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