NON-INTERFERING PHYSIOLOGICAL SENSOR SYSTEM

• US 20130324818A1
• Filed: 08/02/2013
• Published: 12/05/2013
• Est. Priority Date: 10/07/2008
• Status: Abandoned Application

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: GONOPOLSKIY, OLEG, Widman, Ronald A., Anderson, Arik
• Application Number:
  US13/957,564
• Publication Number:
  US 20130324818A1
• Time in Patent Office: Days
• US Class Current: 600/336
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7228 Signal modulation applied to the input signal sent to patient or subject; demodulation to recover the physiological signal modulation H03C

Abstract

A system includes a light source, a photodetector in optical communication with the light source, and a processor in communication with said photodetector and configured to output a signal representing oxygen saturation independent of an interfering signal from an interfering source. The system may further include an analog-to-digital converter in communication with the processor that is configured to digitize a signal from the photodetector by oversampling and output oversampling data to the processor. The processor may include an averaging filter that averages the oversampling data received from said analog-to-digital converter prior to decimation to generate an oversampling number.

Claims

1-20. -20. (canceled)

21. A system comprising:

a light source;

at least one photodetector in optical communication with said light source;

an analog-to-digital converter in communication with said photodetector, said analog-to-digital converter being configured to oversample a signal received from said photodetector and output oversample data; and

a processor in communication with said analog-to-digital converter, said processor being configured to filter said oversample data based at least in part on an oversample number;

wherein said oversample number is derived from at least a sampling frequency of said analog-to-digital converter and a frequency of an interfering signal.

22. A system as set forth in claim 21, wherein said filtering of said oversampled data produces a frequency response having at least one notch at a frequency corresponding to a frequency of the interfering signal.

23. A system as set forth in claim 21, wherein said processor is configured to apply a weighted linear combination to the oversample data.

24. A system as set forth in claim 23, wherein the weighted linear combination includes at least one of a weight and an oversample number that are varied randomly.

25. A system as set forth in claim 21, wherein said photodetector is configured to receive the interfering signal and wherein said processor is configured to calculate a frequency of the interfering signal.

26. A tissue oximeter sensor comprising:

a light source;

a photodetector in optical communication with said light source and configured to output a signal;

a processor in communication with said photodetector and configured to output a signal representing oxygen saturation independent of an interfering signal from an interfering source, wherein said processor is configured to;

select an oversample number based on a sampling frequency of the photodetector output signal and a frequency of the interfering signal; and

reduce the interfering signal in accordance with the oversample number.

27. A tissue oximeter sensor as set forth in claim 26, wherein the oversample number defines a notch in a frequency response of a filter at one or more frequencies associated with the interfering signal.

28. A sensor as set forth in claim 26, further comprising an analog-to-digital converter configured to digitize a signal from said photodetector by oversampling and further configured to output oversampling data to said processor.

29. A sensor as set forth in claim 28, wherein said processor includes an averaging filter in communication with said analog-to-digital converter and is configured to average oversampling data received from said analog-to-digital converter.

30. A sensor as set forth in claim 29, wherein said processor is configured to apply a weighted linear combination to the oversampling data.

31. A sensor as set forth in claim 30, wherein the weighted linear combination includes at least one of a weight and an oversample number.

32. A sensor as set forth in claim 31, wherein the oversample number corresponds to a frequency of the interfering signal.

33. A sensor as set forth in claim 31, wherein the weight corresponds to a frequency of the interfering signal.

34. A sensor as set forth in claim 26, wherein said light source and said photodetector are disposed on a sensor pad.

35. A sensor as set forth in claim 26, wherein said light source is disposed on a first sensor pad and said photodetector is disposed on a second sensor pad.

36. A sensor as set forth in claim 26, wherein the interfering source is a pulse oximeter configured to estimate arterial blood oxygen saturation.

37. A system comprising:

a tissue oximeter sensor having a light source in optical communication with a photodetector and a processor in communication with said photodetector;

an interfering device configured to output an interfering signal having a frequency;

wherein said tissue oximeter is configured to output a signal independent of the interfering signal output by said interfering device by;

selecting an oversample number based on a sampling frequency and the frequency of the interfering signal; and

reducing the interfering signal in accordance with the oversample number.

38. A system as set forth in claim 37, wherein the oversample number defines a notch in a frequency response of a filter at one of more frequencies associated with the interfering signal.

39. A system as set forth in claim 37, wherein said tissue oximeter sensor includes an analog-to-digital converter configured to digitize a signal from said photodetector by oversampling and further configured to output oversampling data to said processor.

40. A system as set forth in claim 39, wherein said processor includes an averaging filter in communication with said analog-to-digital converter and configured to average oversampling data received from said analog-to-digital converter.