Title:
CELL BASE ECHO CANCELLER
Document Type and Number:
Japanese Patent JP3298077
Kind Code:
B2
Abstract:
PURPOSE: To prevent a cell B outer than a user cell A from having an influence upon the echo cancel processing and to prevent the cell B from being affected by this processing by separating the cell B from the user cell A to process the cell B.
CONSTITUTION: A copy of a far-end speaker signal 2 is inputted to a separating part 9, and only the cell A is subjected to a prescribed processing by an ATM layer processing part a15 and an AAL processing part a17, and user data 12 are outputted as sample data to an echo cancel processing part 19. The processing part 9 generates a pseudo echo based on data 12. Meanwhile, a near-end speaker signal 4 is separated by a separating part 10, and the cell B is outputted to an inserting part 23, and the cell A is outputted to the processing part 19 as sample data D after passing the same processing as the signal 2. The processing part 19 subtracts the pseudo echo from data D, and prescribed processings are performed in an AAL processing part b 20 and an ATM layer processing part b 21, an the result is supplied to the inserting part 23. The inserting part 23 inserts the cell B 14 separated by the separating part 10 to the cell A 22 from the processing part b 21 in the same condition as the signal 4 to output them.
Inventors:
Kazuma Miura
Hiroshi Fujitani
Toshiro Mizuno
Hiroshi Fujitani
Toshiro Mizuno
Application Number:
JP31968193A
Publication Date:
July 02, 2002
Filing Date:
December 20, 1993
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
H04B3/23; H04L12/28; H04Q3/00; H04Q3/42; (IPC1-7): H04B3/23; H04L12/28; H04Q3/00; H04Q3/42
Domestic Patent References:
| JP62186626A | ||||
| JP321122A | ||||
| JP4177922A | ||||
| JP4349735A |
Attorney, Agent or Firm:
Masatoshi Isomura