The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 11, 1986
Filed:
Jun. 23, 1983
Walter H Demmer, Hamburg, DE;
Rolf D Gutsmann, Hamburg, DE;
Norbert A Bergs, Hamburg, DE;
Ingolf B Heinemann, Hamburg, DE;
Otto L Warmuth, Hamburg, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
For determining the half-cycle durations of the input signal which is presented as a sequence of sampled values, its zero crossings are approximated by lines which interconnect the two sampled values of different signs on both sides of the zero crossing. The half-cycle duration is derived from the number of sampled values within a period, i.e. between two consecutive zero crossings, and from the time intervals at the beginning and end of each half-cycle determined by the intersection of the approximation line with the axis. The time intervals at the beginning and end of each period are corrected for a more accurate determination of the duration and the time intervals during which the values of the individual half-cycle durations are stored, are made to approximate to these half-cycle durations. The instantaneous frequency of the input signal is determined from the values of the half-cycle durations which have thus been shifted in time by forming the reciprocal.