Signal processing method and device for signal-to-noise improvement

Patent 7060035 Issued on June 13, 2006. Estimated Expiration Date:

June 19, 2023. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3638640

3799672

3847483

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Inventor

Wasserman, Yoram

Assignee

Conmed Corporation

Application

No. 10465128 filed on 06/19/2003

US Classes:

600/508, Heart600/513, Detecting heartbeat electric signal and diverse cardiovascular characteristic600/300, DIAGNOSTIC TESTING356/41, Oximeters356/39, BLOOD ANALYSIS356/40, Hemoglobin concentration356/326, Utilizing a spectrometer600/364, Blood gas600/310, Infrared, visible light, or ultraviolet radiation directed on or through body or constituent released therefrom600/323, Oxygen saturation, e.g., oximeter600/500, Detecting blood vessel pulsation600/322Determining blood constituent

Examiners

Primary: Winakur, Eric F.

Attorney, Agent or Firm

Proskauer Rose LLP

Foreign Patent References

WO 9403102 WO 02/01/1994
WO 0013172 WO 03/01/2000
WO 0154573 WO 08/01/2001
WO 0184107 WO 11/01/2001

International Classes

A61B 5/02
A61B 5/00

Abstract

A method and apparatus extract a signal component of a measured signal using one of two methods. If the signal component in the measured signal is a periodic signal with a certain well-defined peak-to-peak intensity value, upper and lower envelopes of the measured signal are determined and analyzed to extract said signal component of the measured signal. This signal component can further be used to calculate a desired parameter of the sample. The DC component of the signal is determined as the median value of the upper envelope, and the AC component is determined as the median value of the difference between the upper and lower envelopes. If the signal component of the measured signal is a periodic signal characterized by a specific asymmetric shape, a specific adaptive filtering is applied to the measured signal, resulting in the enhancement of the signal component relative to a noise component. This adaptive filtering is based on a derivative of the Gaussian Kernel having specific parameters matching the characteristics of the signal component.

Other References

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