Patent · US Expired

Decision feedback equalizer employing fixed ratio postcursor taps for minimizing noise and intersymbol interference in signals conveyed over high speed data service loop

US5561687A · kind A · utility

58Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 15, 1994
Grant dateOct 1, 1996
Priority date
Expiry dateDec 15, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/03057
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

The feedforward filter section of a decision feedback equalizer is modified to include one or more postcursor taps, that are sequentially weighted at decreasing binary fractions of the cursor tap. Such a modified feedforward filter section, combined with the placement of a simple anti-aliasing filter upstream of the sampling point, results in an optimum feedforward filter configuration that is not anticausal, and offers a substantially improved performance over conventional DFB equalizer structures. Optimum performance is achieved when such a postcursor filter structure is augmented with an adaptive noise canceler coupled in the DFB path.

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