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:
Sep. 24, 1985
Filed:
Aug. 26, 1983
William D Barber, Ballston Lake, NY (US);
Jeffrey W Eberhard, Schenectady, NY (US);
Steven G Karr, Clifton Park, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
Accurate estimates of the instantaneous mean frequency of a time varying signal are achieved at favorable and adverse signal-to-noise ratios by an improved time domain approach. Demodulated in-phase and quadrature signals are sampled and delayed. Noise in both terms of a simple arc tangent algorithm, whose denominator has products of time samples shifted at least one time period with respect to itself, is uncorrelated and removed by low pass filtering. One embodiment is a pulsed ultrasonic Doppler system with quadrature detection to measure and display blood velocity as a function of time.