Patent · US Expired

Digital phase detector

US5001489A · kind A · utility

18Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 2, 1988
Grant dateMar 19, 1991
Priority date
Expiry dateNov 2, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R25/00
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A phase detector receives two input digital signals representing Cartesian coordinates of a vector and outputs a digital signal indicative of the phase angle of the vector. The input digital signals are logarithms of the square of, for example, in-phase and quadrature components of a radar signal and are subtracted in the phase detector to produce a difference signal having a magnitude and a polarity. The polarities of the difference signal and the two information signals are used to determine the octant of the phase angle by addressing a read only memory. The magnitude of the difference signal is used as an address of a read only memory storing digital values corresponding to angles within an octant. The octant output by the first read only memory and the angle output by the second read only memory together indicate the phase angle of the vector.

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