Process for determining an echo path flat delay and echo canceler using said process
US4764955A · kind A · utility
55Cited by
8References
6Claims
0Family size
Assignee
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Key dates
| Filing date | Oct 16, 1986 |
| Grant date | Aug 16, 1988 |
| Priority date | — |
| Expiry date | Oct 16, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a voice transmission network having an echo canceler including a flat delay line in series with an adaptive digital filter, a process is provided for adjusting the flat delay line length, thus enabling limiting the filter length to minimal value. The method is based on intercorrelation operations. It includes first intercorrelating sequences of energy values of blocks or consecutive samples, to derive a rough flat delay estimation therefrom; then intercorrelating sequences of signal samples with one of the sequences being roughly delayed, to derive therefrom an accurate flat delay estimation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.