Patent · US Expired

Clocking method and apparatus for use with partial response coded binary data

US4970609A · kind A · utility

66Cited by
3References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 1988
Grant dateNov 13, 1990
Priority date
Expiry dateOct 17, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L7/007
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Clocking of Class IV partial response coded binary data is provided by way of circuit means that includes two analog threshold detectors. One detector is responsive to the analog read signal's positive-going amplitude corssing a a preset positive threshold value. The other detector is responsive to the read signal's negative-going amplitude crossing a preset negative value. The time of occurrence of both detector crossing transitions is phase-compared to a clock signal, and a phase error signal is generated for each detector, if a phase error exists. The two phase error signals are integrated by the use of a loop filter. The integrated phase error signal is then used to adjust the phase of a clock signal generator. The output of the clock signal generator is used to accurately clock, and to enable accurate recover of, the binary data that was originally encoded and written in accordance with the Class IV partial responsive coding convention.

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