Signal processing apparatus

• US 20080033266A1
• Filed: 08/20/2007
• Published: 02/07/2008
• Est. Priority Date: 10/07/1994
• Status: Active Grant

• Current Assignee: Esmaiel Kiani-Azarbayjany, Ibrahim Elfadel, Mohamed K. Diab, Rex J. Mccarthy, Robert Smith, Walter Weber
• Original Assignee: Esmaiel Kiani-Azarbayjany, Ibrahim Elfadel, Mohamed K. Diab, Rex J. Mccarthy, Robert Smith, Walter Weber
• Inventors: Smith, Robert, Diab, Mohamed, Kiani-Azarbayjany, Esmaiel, Weber, Walter, Elfadel, Ibrahim, McCarthy, Rex
• Granted Patent: US 8,019,400 B2
• Time in Patent Office: Days
• US Class Current: 600/336
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02154 by optical transmission
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• 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 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/369 Electroencephalography [EEG] devices for psychotechnics A61B5/16
• CPC Class Codes: A61B 5/4821 Determining level or depth of anaesthesia A61B5/1106 takes precedence
• CPC Class Codes: A61B 5/7214 using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61B 5/7253 characterised by using transforms
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 6/00 Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment instruments measuring radiation intensity for application in the field of nuclear medicine, e.g. in vivo counting, G01T1/161; apparatus for taking X-ray photographs G03B42/02
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61B 8/5276 : due to motion
• CPC Class Codes: G06F 2218/04 : Denoising
• CPC Class Codes: H04B 1/123 : using adaptive balancing or compensation means adaptive filter circuits and algorithms H03H

Abstract

The present disclosure describes a method and an apparatus for analyzing measured signals using various processing techniques. In certain embodiments, the measured signals are physiological signals. In certain embodiments, the measurements relate to blood constituent measurements including blood oxygen saturation.

Claims

1. A physiological monitoring system configured to receive one or more intensity signals representative of at least one physiological characteristic of body tissue and determine a resulting value indicative of the at least one physiological characteristic, the physiological monitoring system comprising:

an input configured to receive one or more intensity signals representative of a physiological characteristic of body tissue; and

a signal processing device configured to utilize a first calculation technique to determine at least a first value representative of the physiological characteristic of body tissue and a second calculation technique, different from the first calculation technique, to determine at least a second value representative of the physiological characteristic of body tissue, and further configured to utilize at least one of the first and second calculation technique to determine a resulting value indicative of the at least one physiological characteristic.

2. The physiological monitoring system of claim 1, wherein the at least one physiological characteristic comprises a blood constituent level.

3. The physiological monitoring system of claim 2, wherein the blood constituent level comprises blood oxygen saturation.

4. The physiological monitoring system of claim 3, wherein the value comprises a ratio.

5. The physiological monitoring system of claim 3, wherein the value of the blood oxygen saturation is significantly free of an influence of motion induced noise.

6. The physiological monitoring system of claim 1, wherein the signal processing device is further configured to utilize the first calculation technique and the second calculation technique, and wherein the resulting value is a combination of the first and second calculation values.