ULTRASONIC DIAGNOSIS DEVICE AND METHOD FOR MEASURING BLOOD FLOW RATE USING DOPPLER EFFECT

摘要

PURPOSE: An ultrasonic diagnosis device and a method for measuring blood flow rate using Doppler effect are provided to select effectively an RF area used to calculate a noise threshold from positive or negative frequency areas and to determine an optimum pulse repetition frequency without generating aliasing. CONSTITUTION: A sample data generator generates sample data by transmitting ultrasonic signals to a human body and sampling a reflected signal. A converter processes the sample data to generate frequency distribution data displaying the distribution of blood flow rate. A noise area determinator determines an area formed of noise from the positive and negative frequency areas of the frequency distribution data. A noise threshold determinator(501) determines a noise threshold using predetermined frequency components the frequency area determined to be an area formed of noise by the noise area determinator. A maximum rate determinator(304) determines a maximum frequency component having power lever higher than the noise threshold using the noise threshold.