Method for Determining Sleep Stages

• US 20080039736A1
• Filed: 02/23/2005
• Published: 02/14/2008
• Est. Priority Date: 03/01/2004
• Status: Active Grant

• Current Assignee: Sleep System Laboratory Inc.
• Original Assignee: CB System Co.
• Inventors: Nemoto, Shin
• Granted Patent: US 7,699,785 B2
• Time in Patent Office: Days
• US Class Current: 600/544
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/4812 Detecting sleep stages or cycles
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: A61B 7/02 Stethoscopes acoustic details thereof G10K11/00
• CPC Class Codes: G08B 21/0461 integrated or attached to an item closely associated with the person but not worn by the person, e.g. chair, walking stick, bed sensor

Abstract

The present invention provides a method for determining sleep stages of an examinee, including detecting signals of the examinee with a biosignal detector, calculating a signal strength deviation value that indicates deviation of a signal strength of the detected signals, and determining a sleep stage by using the signal strength deviation value or a value of a plurality of values based on the signal strength deviation value as an indicator value.

Claims

1. A method for determining sleep stages of an examinee, the method comprising:

detecting signals of the examinee with a biosignal detector;

calculating a signal strength deviation value that indicates deviation of a signal strength of the detected signals; and

determining a sleep stage by using the signal strength deviation value or a value of a plurality of values based on the signal strength deviation value as an indicator value.

2. The method for determining sleep stages of an examinee according to claim 1, wherein the indicator value is the signal strength data deviation value detected in a predetermined time period.

3. The method for determining sleep stages of an examinee according to claim 1, wherein the indicator value is a signal of a difference between signal strength data deviation value detected in a predetermined time period and a moving average of the deviation value.

4. The method for determining sleep stages of an examinee according to claim 1, wherein the indicator value is a moving average calculated from the signal strength data deviation value detected in a predetermined time period.

5. The method for determining sleep stages of an examinee according to claim 1, wherein a signal strength deviation signal value obtained by removing abnormal values from the signal strength deviation value or a value of a plurality of values based on the signal strength deviation value is used as the indicator value.

6. The method for determining sleep stages of an examinee according to claim 1, wherein the signal strength is the signal strength obtained as a reciprocal of a coefficient obtained by gain-controlling the detected signals.

7. The method for determining sleep stages of an examinee according to claim 1, wherein the biosignal detector is a non-invasive biosignal detector.

8. The method for determining sleep stages of an examinee according to claim 7, wherein the biosignal detector comprises:

a pressure detection tube;

a pressure detection sensor; and

a biosignal extractor, wherein the biosignal extractor extracts biosignals from a pressure variation detected by the pressure detection sensor.

9. The method for determining sleep stages of an examinee according to claim 1, wherein the biosignal detector is a heartbeat signal detector, such as at least one of an electrocardiograph and a pulse rate meter.