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:
Apr. 02, 1996
Filed:
Oct. 12, 1993
Richard D Pering, Palo Alto, CA (US);
Don Goodnature, Santa Clara, CA (US);
James M Lindauer, San Francisco, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
During sampling, a finite impulse response (FIR) filter separates a composite signal into two components, non-cardiac physiological phenomena and cardiac artifacts. The length of the filter window dynamically varies to produce an output signal in which the cardiac frequency and any associated harmonics are suppressed. The FIR filter is applied to the patient signal and lags the patient signal by at least one interval between triggering events. When the present interval between triggering events passes by the filter window, the window length is gradually adjusted to have the same length as the next period such that the triggering events are synchronized with the endpoints of the filter window at the start of each interval. The difference between the present interval and the next interval is evenly distributed or subtracted across the filter window between synchronizations.