METHOD AND/OR SYSTEM FOR SENSOR ARTIFACT FILTERING

• US 20100168538A1
• Filed: 12/31/2008
• Published: 07/01/2010
• Est. Priority Date: 12/31/2008
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Mastrototaro, John J., Keenan, Desmond Barry
• Granted Patent: US 9,320,470 B2
• Time in Patent Office: Days
• US Class Current: 600/365
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/07 Endoradiosondes
• CPC Class Codes: A61B 5/1411 by percutaneous method, e.g. by lancet
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14865 invasive, e.g. introduced into the body by a catheter or needle or using implanted sensors
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6848 Needles
• CPC Class Codes: A61B 5/6849 in combination with a needle set
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/725 using specific filters therefor, e.g. Kalman or adaptive filters A61B5/316 take precedence
• CPC Class Codes: A61M 2205/3569 sublocal, e.g. between console and disposable
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2230/201 Glucose concentration
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00

Abstract

Disclosed are a method and/or system for filtering sensor measurements. In one particular implementation, a sensor signal may be processed concurrently in a plurality of signal-filter paths. A particular signal-filter path may be selected to provide an output signal for obtaining a measurement based, at least in part, on a measurement of noise associated with the sensor signal.

Claims

1. A method comprising:

providing a signal representative of a blood glucose concentration; and

selecting an output signal for use in estimating said blood glucose concentration from among a plurality of signal-filter paths based, at least in part, on a measurement of noise associated with said signal.

2. The method of claim 1, and further comprising:

generating said signal based upon a measurement of said blood glucose concentration; and

obtaining said measurement of said noise contemporaneous with obtaining said measurement of said blood glucose concentration.

3. The method of claim 1, wherein said plurality of signal-filter paths comprises at least one signal-filter path with no filtering and at least one signal-filter path comprising a finite impulse response (FIR) filter.

4. The method of claim 3, and further comprising selecting said output signal from said at least one signal-filter path with no filtering if said measurement of said noise is below a threshold level.

5. The method of claim 1, and further comprising:

high-pass filtering said signal to provide an isolated noise component; and

determining said measurement of noise based, at least in part, on said isolated noise component.

6. The method of claim 1, and further comprising receiving said signal representative of said blood-glucose concentration from a blood-glucose sensor implanted in a patient.

7. The method of claim 1, and further comprising:

selecting an output signal for use in estimating said blood glucose concentration from a different one of said plurality signal-filter paths based, at least in part, in a change in said measurement of noise.

8. The method of claim 1, wherein at least one signal-filter path comprises a seventh-order FIR filter.

9. The method of claim 1, wherein at least one signal-filter path comprises an infinite impulse response filter.

10. The method of claim 1, wherein at least one signal-filter path comprises a Kalman filter.

11. An apparatus comprising:

means for providing a signal representative of a blood glucose concentration; and

means for selecting an output signal for use in estimating said blood glucose concentration from among a plurality of signal-filter paths based, at least in part, on a measurement of noise associated with said signal.

12. The apparatus method of claim 11, and further comprising:

means for generating said signal based upon a measurement of said blood glucose concentration; and

means for obtaining said measurement of said noise contemporaneous with obtaining said measurement of said blood glucose concentration.

13. The apparatus of claim 11, wherein said plurality of signal-filter paths comprises at least one signal-filter path with no filtering and at least one signal-filter path comprising a finite impulse response (FIR) filter.

14. The apparatus of claim 13, and further comprising means for selecting said output signal from said at least one signal-filter path with no filtering if said measurement of said noise is below a threshold level.

15. The apparatus of claim 11, and further comprising:

means for high-pass filtering said signal to provide an isolated noise component; and

means for determining said measurement of noise based, at least in part, on said isolated noise component.

16. The apparatus of claim 11, and further comprising means for receiving said signal representative of said blood-glucose concentration from a blood-glucose sensor implanted in a patient.

17. The apparatus of claim 11, and further comprising:

means for selecting an output signal for use in estimating said blood glucose concentration from a different one of said plurality signal-filter paths based, at least in part, in a change in said measurement of noise.

18. An apparatus comprising:

a blood-glucose sensor to generate a sensor signal representative of a blood-glucose concentration in a patient; and

a controller adapted to select an output signal for use in estimating said blood glucose concentration from among a plurality of signal-filter paths based, at least in part, on a measurement of noise associated with said sensor signal.

19. The apparatus of claim 18, and further comprising said plurality of filter-signal paths, said plurality of filter-signal paths being adapted to concurrently process sensor signal to provide respective candidate output signals.

20. The apparatus of claim 19, wherein said plurality of signal-filter paths comprises at least one signal-filter path with no filtering and at least one signal-filter path comprising a finite impulse response (FIR) filter.

21. The apparatus of claim 18, and further comprising:

a high-pass filter to provide an isolated noise component, and wherein said controller is adapted to determine said measurement of noise based, at least in part, on said isolated noise component.

22. The apparatus of claim 18, and further comprising an insulin delivery system adapted to inject insulin into said patient in response to one or more control signals from said controller, said controller being adapted to generate said one or more control signals based, at least in part, on an estimate of said blood-glucose concentration.

23. An article comprising:

a storage medium comprising machine-readable instructions which, if executed by a computing platform, are adapted to direct said computing platform to;

select an output signal for use in estimating a blood glucose concentration from among a plurality of signal-filter paths based, at least in part, on a measurement of noise associated with a signal representative of a blood-glucose concentration.

24. The article of claim 23, wherein said instructions, if executed by said computing platform, are further adapted to direct said computing platform to select said output signal from said at least one signal-filter path with no filtering if said measurement of said noise is below a threshold level.

25. The article of claim 23, wherein said instructions, if executed by said computing platform, are further adapted to direct said computing platform to select an output signal for use in estimating said blood glucose concentration from a different one of said plurality signal-filter paths based, at least in part, in a change in said measurement of noise.