Patent · US Expired

Apparatus for, and method of, processing signals transmitted over a local area network

US6178198A · kind A · utility

24Cited by
16References
51Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 14, 1997
Grant dateJan 23, 2001
Priority date
Expiry dateNov 14, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2025/03503
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Digital signals provided by a repeater connected to a plurality of clients by unshielded twisted wire pairs, are converted to analog signals which become degraded during transmission through the wires. Clients convert the degraded analog signals to digital signals. Digital signal phases are coarsely adjusted to have assumed zero crossing times coincide in-time with a clock signal zero crossing. Signal polarity, and the polarity of any change, is determined at the assumed zero crossing times of the digital signals. Pre-cursor and post-cursor responses, resulting from signal degradation, are respectively inhibited by a feed forward and a decision feedback equalizer. The time duration of post-cursor response is further inhibited by a high pass filter and a tail canceller. Phase adjustments are made, after response inhibition, by determining the polarity, and the polarity of any change, at the assumed zero crossing times. Before phase adjustments are made, a phase offset is provided in order to compensate for phase degradations introduced by the unshielded twisted wire pairs.

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