Patent · US Expired

Sparse echo canceller

US7107303B2 · kind B2 · utility

3Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 23, 2003
Grant dateSep 12, 2006
Priority date
Expiry dateJan 11, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B3/238
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An echo canceller includes an adaptive digital filter that generates an estimated echo signal {circumflex over (z)}[k] in response to (i) a sampled input data sequence x[k] and (ii) an error signal sequence e[k] indicative of the difference between a far end signal sequence y[k] and the estimated echo signal {circumflex over (z)}[k]. The adaptive filter includes N filter taps that each provide an associated tap output signal, wherein the adaptive digital filter generates the estimated echo signal {circumflex over (z)}[k] using the associated tap output signals from M of the N filter taps selected in response to a time delay estimate signal. The adaptive filter computes filter coefficients for each of the M number of the N filter taps using the associated tap output signals from the M number of said N filter taps. The echo canceller also includes a time delay estimator that is responsive to the sampled input data sequence x[k] and the signal sequence y[k], and estimates a plurality of delays within the sequence x[k], and provides a time delay estimate that is indicative of the location of the plurality of delays within the sequence x[k]. A summer computes the difference between sign…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.