Patent · US Expired

Method and apparatus for digitally evaluating the phase of a modulated carrier

US5740202A · kind A · utility

1Cited by
4References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 22, 1995
Grant dateApr 14, 1998
Priority date
Expiry dateSep 22, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2027/0067
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

The method makes it possible digitally to evaluate the phase of any carrier that has been subjected to rPSK modulation subsequent to clock recovery, sampling, and digitizing the in-phase and quadrature components of the samples, by processing that is performed in polar coordinates and that comprises reducing the range over which the phase of each sample is defined to a range of +.pi./r to -.pi./r and then seeking the center of gravity over 2.sup.N successive samples (N being an integer) by performing successive averaging calculations, each time on two values, in application of an N-stage tree structure. Each average of two values is associated with an index indicative of the degree of reliability of the average, and those averages which are associated with a small reliability index are ignored while calculating subsequent averages in the tree structure.

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