Title:
METHOD AND DEVICE FOR DIGITALLY REMOVING ECHO GENERATED DURING CONNECTION WITH TIME VARYING CHARACTERISTIC
Document Type and Number:
Japanese Patent JPS60167530
Kind Code:
A
Abstract:
The method provides the use, for the determination of the estimation echo-channel pulse response, of digital filtering techniques of the transversal adaptive type, and the subdivision of the pulse-response of the equivalent echo channel into three intervals, the second of which consists of the significant portion of the pulse response and is determined by the iterative search for the value and the position of the coefficient of maximum absolute value; the first interval corresponds to a pure delay and the third corresponds to the contribution given by the lowest frequencies of the base band. To copy the echo-signal, there are only considered the pulse-response coefficients whose indexes are comprised in the second interval, and the samples of the signals to be copied belonging to preceding sampling instants, whose indexes are also comprised in the second interval.
More Like This:
| JPH05206900 | ECHO CANCELLER |
Inventors:
RUCHIAANO NETSUBIA
ROBERUTO MONTAANIA
ROBERUTO MONTAANIA
Application Number:
JP21161284A
Publication Date:
August 30, 1985
Filing Date:
October 11, 1984
Export Citation:
Assignee:
CSELT CENTRO STUDI LAB TELECOM
TERESUBACHIO SPA PERU RE KOMIY
TERESUBACHIO SPA PERU RE KOMIY
International Classes:
H04B3/20; H04B3/23; (IPC1-7): H04B3/20
Domestic Patent References:
| JPS5225516A | 1977-02-25 |
Foreign References:
| US3721777A | 1973-03-20 |
Attorney, Agent or Firm:
Kawahara Kazuho
Previous Patent: JPS60167529
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