Apparatus and method of estimating echo path delay
US6625279B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 19, 2000 |
| Grant date | Sep 23, 2003 |
| Priority date | — |
| Expiry date | Apr 2, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Disclosed is an echo path delay estimating apparatus and method for estimating the echo path delay using decimators and an adaptive filter, so that a short computation time is used by the echo canceller. The apparatus comprising: a first low pass filter for receiving a the sound signal as a first sound signal and for filtering the first sound signal at a predetermined bandwidth; a first decimator for decimating the output signal of the first low pass filter at a predetermined decimation rate; a second low pass filter for receiving the echo caused by the first sound signal as a second sound signal and for filtering the second sound signal at a predetermined bandwidth; a second decimator for decimating the output signal of the second low pass filter at a predetermined decimation rate; an adaptive filter for receiving the output signal of the first and second decimators to compute an echo delay estimation value; and, a canceller for subtracting the echo delay estimation value from the output signal of the second decimator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.