Patent · US Expired

Frequency measurement

US5019823A · kind A · utility

7Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 5, 1989
Grant dateMay 28, 1991
Priority date
Expiry dateDec 5, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R23/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An apparatus for measuring the frequency of an input signal is described. The apparatus uses a quadrature sampling system to obtain values of the instantaneous phase of the signals at a succession of time intervals, the values being converted into cumulative phase values. An estimate of the frequency is obtained by determining the gradient of the straight line which would best pass through a plot of the values of cumulative phase against time.

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