SE8205841L - echo canceller - Google Patents
echo cancellerInfo
- Publication number
- SE8205841L SE8205841L SE8205841A SE8205841A SE8205841L SE 8205841 L SE8205841 L SE 8205841L SE 8205841 A SE8205841 A SE 8205841A SE 8205841 A SE8205841 A SE 8205841A SE 8205841 L SE8205841 L SE 8205841L
- Authority
- SE
- Sweden
- Prior art keywords
- echo
- signal
- generating means
- preliminary
- echo replica
- Prior art date
Links
Classifications
-
- 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
- H04B3/237—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 using two adaptive filters, e.g. for near end and for end echo cancelling
-
- 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
-
- 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
- H04B3/238—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 using initial training sequence
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Radio Relay Systems (AREA)
Abstract
An echo canceller arrangement performs a two-stage cancellation while employing only a single echo replica generating means (18). Initially the generating means (18) generates a preliminary echo replica signal (@1(k)) in response to the application by switching means (24) of the resulting preliminary echo cancelled signal (e1(k)) to the echo replica generating means. When the controller (26) deems that sufficient cancellation has taken place ie the preliminary echo cancelled signal is reduced to a level below that at which it might wrongly be identified as near end speech by detector 30, the switching means (24) is activated to provide a final echo cancelled signal (e2(k)) to the echo replica generating means to form the second echo replica signal y2(k), the final value of the preliminary echo replica signal @1(k) being stored in RAM (28). <IMAGE>
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US31435381A | 1981-10-23 | 1981-10-23 |
Publications (2)
Publication Number | Publication Date |
---|---|
SE8205841D0 SE8205841D0 (en) | 1982-10-14 |
SE8205841L true SE8205841L (en) | 1983-04-24 |
Family
ID=23219622
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
SE8205841A SE8205841L (en) | 1981-10-23 | 1982-10-14 | echo canceller |
Country Status (8)
Country | Link |
---|---|
JP (1) | JPS5881345A (en) |
KR (1) | KR840002178A (en) |
AU (1) | AU8965582A (en) |
DE (1) | DE3238550A1 (en) |
FR (1) | FR2515453A1 (en) |
GB (1) | GB2109208A (en) |
NL (1) | NL8204100A (en) |
SE (1) | SE8205841L (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CA1186764A (en) * | 1982-06-23 | 1985-05-07 | Akira Kanemasa | Echo canceler |
EP0117626A3 (en) * | 1983-02-04 | 1985-12-18 | Western Electric Company, Incorporated | Improvements in or relating to adaptive filter arrangements |
GB8423017D0 (en) * | 1984-09-12 | 1984-10-17 | Plessey Co Plc | Echo canceller |
CA1238381A (en) * | 1985-03-14 | 1988-06-21 | Ephraim Arnon | Multi-stage echo canceller |
US4868874A (en) * | 1986-04-18 | 1989-09-19 | Hitachi, Ltd. | Echo canceller |
US5471527A (en) | 1993-12-02 | 1995-11-28 | Dsc Communications Corporation | Voice enhancement system and method |
KR100586586B1 (en) * | 1999-12-18 | 2006-06-02 | 주식회사 케이티 | Weight Varying Method for Interference Cancellation |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1816153B2 (en) * | 1968-12-20 | 1971-04-15 | CIRCUIT ARRANGEMENT FOR ECHO SUPPRESSION IN A TALK CIRCUIT ON A FOUR WIRE TRANSMISSION SYSTEM IN THE CASE OF A TRANSITION TO A TWO WIRE TRANSMISSION PATH | |
US4057696A (en) * | 1976-08-09 | 1977-11-08 | Bell Telephone Laboratories, Incorporated | Recursive-like adaptive echo canceller |
EP0053202B1 (en) * | 1980-12-06 | 1985-03-27 | Communications Satellite Corporation | Improved double talk detector for echo cancellers |
-
1982
- 1982-10-14 SE SE8205841A patent/SE8205841L/en not_active Application Discontinuation
- 1982-10-18 DE DE19823238550 patent/DE3238550A1/en not_active Withdrawn
- 1982-10-18 FR FR8217372A patent/FR2515453A1/en not_active Withdrawn
- 1982-10-20 GB GB08229957A patent/GB2109208A/en not_active Withdrawn
- 1982-10-21 KR KR1019820004731A patent/KR840002178A/en unknown
- 1982-10-21 AU AU89655/82A patent/AU8965582A/en not_active Abandoned
- 1982-10-22 NL NL8204100A patent/NL8204100A/en not_active Application Discontinuation
- 1982-10-23 JP JP57185392A patent/JPS5881345A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
JPS5881345A (en) | 1983-05-16 |
DE3238550A1 (en) | 1983-06-30 |
FR2515453A1 (en) | 1983-04-29 |
NL8204100A (en) | 1983-05-16 |
KR840002178A (en) | 1984-06-11 |
GB2109208A (en) | 1983-05-25 |
SE8205841D0 (en) | 1982-10-14 |
AU8965582A (en) | 1983-04-28 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
NAV | Patent application has lapsed |
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