Patent ID: 9585573
Date: 2017-03-07
CPC Classifications: A61B

Claim:
1. A method of estimating blood pressure, the method comprising: obtaining, by at least one sensor, a pressure wave detected at a measurement body part of a subject and a reference pressure wave detected at a reference measurement body part of the subject which is different from the measurement body part; determining, by at least one processor, an index to be a difference between a blood pressure determined by applying a fixed characteristic ratio and a blood pressure having a maximum amplitude of the detected pressure wave which is transmitted by the at least one sensor; calculating, by at least one processor, a reference characteristic ratio using the detected reference pressure wave which is transmitted by the at least one sensor; calculating, by at least one processor, a variable characteristic ratio based on a correlation between the determined index and the reference characteristic ratio; estimating, by at least one processor, blood pressure at the measurement body part of the subject using the calculated variable characteristic ratio; and outputting, by an output unit, the blood pressure at the measurement body part of the subject, wherein the fixed characteristic ratio comprises a characteristic ratio which is fixed and irrespective of the shape of the pressure wave, wherein the variable characteristic ratio comprises a characteristic ratio which is a calculated characteristic ratio of the subject and variable according to the shape of the obtained pressure wave, and wherein the reference characteristic ratio comprises a characteristic ratio which is used to determine blood pressure at a measurement body part and determined using a reference blood pressure measured at the reference measurement body part.