HEART RATE METER AND METHOD FOR REMOVING NOISE OF HEART BEAT WAVEFORM

• US 20090112111A1
• Filed: 09/05/2006
• Published: 04/30/2009
• Est. Priority Date: 09/15/2005
• Status: Active Grant

• Current Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Original Assignee: Citizen Holdings Co., Ltd. (Citizen Electronics Company Limited)
• Inventors: Shimizu, Hideki, Kasai, Tsuneharu
• Granted Patent: US 8,897,864 B2
• Time in Patent Office: Days
• US Class Current: 600/520
• 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 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts

Abstract

A heart rate meter for measuring the heart rate of a living body includes a heart rate variation detecting unit 5 for measuring the variation of the heart rate determined from a heart beat waveform, and a heart rate error detecting and correcting unit 6 for detecting an error of heart rate on the basis of the trend of the heart rate variation and correcting the heart rate error being detected. The heart rate error detecting and correcting unit 6 includes a heart rate error detecting unit 6A for detecting an error of the heart rate variation as a heart rate error on the basis of the trend of the heart rate variation, and a heart rate error correcting unit 6B for correcting the error of heart rate according to the detection of the heart rate error. An accurate heart rate is acquired even if main components of the heart beats are lost because of a large noise due to body movement, or the like.

Claims

1-26. -26. (canceled)

27. A heart rate meter for measuring a heart rate of a living body, comprising,

a heart rate variation detecting unit for obtaining a heart rate variation determined from a heart beat waveform, and

a heart rate error detecting and correcting unit for detecting a heart rate error based on a trend of the heart rate variation and correcting the heart rate error being detected.

28. The heart rate meter according to claim 27, wherein,

the heart rate variation detecting unit obtains a heart rate variation from a variation in the heart rate every predetermined period of time.

29. The heart rate meter according to claim 28, wherein,

the heart rate variation detecting unit obtains the heart rate variation from a difference in sampling values of the heart rate.

30. The heart rate meter according to claim 27, wherein,

the heart rate variation detecting unit obtains the heart rate variation from a differential value of the heart rate at a predetermined point of time.

31. The heart rate meter according to claim 27, wherein,

the heart rate variation is obtained from a heart beat waveform under a certain exercise load being applied.

32. The heart rate meter according to claim 27, wherein,

the heart rate error detecting and correcting unit further comprising,

a heart rate error detecting unit for detecting the heart rate variation error based on the trend of the heart rate variation, so as to detect a heart rate error, and

a heart rate error correcting unit for correcting the heart rate error according to the heart rate error being detected.

33. The heart rate meter according to claim 27, wherein,

the heart rate error detecting unit further comprising,

a heart rate variation error detecting part for comparing a trend of the heart rate variation of a target heart rate with a trend of a reference heart rate variation as a standard, and detecting an error in the target heart rate variation based on a trend similarity between both of the heart rate variations, and

a heart rate variation error correcting part for correcting the heart rate variation error.

34. The heart rate meter according to claim 33, wherein,

the heart rate variation error detecting unit assumes;

multiple number of heart rate variation values included in the target heart rate variation within a predetermined time zone, as the trend of the heart rate variation,

the heart rate variation values of the same number held in the reference heart rate variation within the same predetermined time zone, as the trend of the reference heart rate variation, and

differences between the heart rate variation values associated respectively in both trends, as the trend similarity, and detects an error in the target heart rate variation.

35. The heart rate meter according to claim 33, further comprising,

a reference heart rate variation pattern storage, for storing multiple reference heart rate variation patterns, each being made up of a different combination of heart rate variation values, wherein,

the heart rate variation error detecting unit,

compares a reference heart rate variation pattern estimated from the multiple reference heart rate variation patterns with the target heart rate variation, and

assumes differences between the heart rate variation values associated respectively in both heart rate variations, as the trend similarity, so that an error in the target heart rate variation is detected.

36. The heart rate meter according to claim 35, wherein,

the heart rate variation error detecting part reads the reference heart rate variation pattern from the reference heart rate variation pattern storage, in sync with timing when an exercise load is applied.

37. The heart rate meter according to claim 34, wherein,

the heart rate variation error detecting part detects the heart rate variation error based on the number of the target heart rate variation values each having a difference which goes over a set value.

38. The heart rate meter according to claim 33, wherein,

the heart rate variation error correcting part corrects the heart rate variation value of the target heart rate variation detected by the heart rate variation error detecting part to the heart rate variation value of the reference heart rate variation.

39. The heart rate meter according to claim 33, wherein,

the heart rate error correcting unit corrects an associating heart rate based on the heart rate variation value that is detected and corrected by the heart rate error detecting unit.