Patent · US Expired

Method of obtaining a phase difference signal

US4843616A · kind A · utility

7Cited by
11References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 8, 1988
Grant dateJun 27, 1989
Priority date
Expiry dateMar 8, 2008

Classification

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

Abstract

A method of obtaining a signal representing the phase difference between a local carrier signal and the carrier of an amplitude and/or phase shift keyed received signal wherein: the received signal is divided into two cartesian coordinate signal components which are a function of the phase difference and are in a quadrature relationship to one another; each pair of cartesian coordinate signal components, each representing one of a plurality of permitted signal states, is converted into two corresponding polar coordinate signal components, a decision is then made as to which is the permitted, unfalsified polar signal components which the polar signal components of the received signal most closely approach; and the phase difference is derived from a comparison between the decided-upon polar signal components and the received polar signal components.

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