Partitioned echo canceler utilizing decimation echo location
US5721782A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1996 |
| Grant date | Feb 24, 1998 |
| Priority date | — |
| Expiry date | Mar 25, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/23
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention includes an adaptive filter (40) for use within an echo canceler. The adaptive filter operates in a first mode for performing Decimation Echo Location (DEL). During the DEL mode, high energy regions occurring within the echo impulse response are identified over an extended time range through signal decimation. The adaptive filter then operates in a second mode for performing Partitioned Echo Cancellation (PEC). During the PEC mode, filter coefficients not associated with these high energy regions are modeled as zero while the identified high energy region filter coefficients of the impulse response are partitioned and convolution of the reference signal, x(n), with the impulse response signal, h(n), is accomplished by performing convolution on only those samples in the reference signal memory block (50) that correspond to respective high energy region filter coefficients in the adaptive filter block (56). Accordingly, the adaptive filter of the present invention extends the tail length time range of conventional adaptive filters while not increasing the number of required filter coefficient taps and substantially reduces the number of convolution multiply accu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.