Patent · US Expired

Adaptive cable equalizer

US5978417A · kind A · utility

55Cited by
4References
50Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 13, 1996
Grant dateNov 2, 1999
Priority date
Expiry dateSep 13, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B3/145
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An adaptive cable equalizer is provided with a simple architecture, wherein a single control structure: controls the adaptation of the filter for compensating for cable length while simultaneously compensating for process and temperature variations; optimizes the SNR at any cable length by controlling biasing current sources; and uses a two-stage architecture which eliminates start-up problems and optimizes output levels to obtain optimal dc restoration while simultaneously allowing for independent optimization of the output levels of the recovered data in accordance with other requirements as desired. An analog adaptive equalizing filter is used for accurately synthesizing the inverse transfer function of cables of variable lengths. Data rates up to and beyond 400 Mbps are supported and the adaptive behavior automatically compensates for different cable lengths as well as process variations (with respect to the process(es) used for fabricating the equalizer in a monolithic form) and temperature variations.

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