Velocity distribution measuring method based on ultrasonic interleave programming

Abstract

The invention discloses a velocity distribution measuring method based on ultrasonic interleave programming. The method includes the steps: 1) adding tracer into to-be-tested fluid; 2) using a controller to control a high-frequency ultrasonic transducer to outwardly transmit high-frequency ultrasonic signals by means of interleave programming, and acquiring backscattering radio-frequency signals of the tracer in the fluid; 3) on the basis of the step 2), decoupling an interleaved radio-frequency image acquired by means of interleave programming to obtain an image pair; and 4) on the basis of the step 3), partitioning the two frame radio-frequency signal image 1 and image 2 acquired by means of interleave programming into a plurality of analysis windows, namely inquiry windows, subjecting the inquiry windows to two-dimensional cross-correlation operation within the Fourier space to acquire local displacement of the tracer, and calculating according to a time interval delta t of the two frames of images to obtain velocity vector, namely using the displacement to divide the time delta t. The method can be used for measuring fluid velocity field under high-flow-velocity conditions.

Description

technical field [0001] The invention relates to a method for collecting ultrasonic radio frequency signals to measure velocity field by using the principle of interleaving programming. Background technique [0002] Ultrasonic imaging velocimetry technology is a non-invasive flow field measurement technology, which can realize the measurement of non-transparent fluid and flow channel wall velocity field, and can be used to accurately measure the clinical blood flow field and realize the real-time distribution of blood complex flow field in the human body. It is of great significance for the accurate diagnosis and clinical research of various cardiovascular diseases. [0003] The linear ultrasonic probe used in the process of ultrasonic imaging speed measurement is composed of multiple unit arrays. When image acquisition is performed, first a group of unit arrays excites the transducer to generate ultrasonic waves in the measurement area through a high-frequency signal generat...

AI Technical Summary

Problems solved by technology

Even if expensive equipment can scan multiple lines at the same time, increase the frame rate of image acquisition, and reduce the particle offset to the width of several lines within one frame of image acquisition time, it has the disadvantage of flow oversampling, such as a typical The duration of the cardiac cycle is about 1 second. Sampling at a frequency of 750-1000 Hz will generate a large amount of redundant data, because even if the image acquisition frame rate is an order of magnitude lower than the above image acquisition frame rate, it is enough to distinguish the cardiac hemodynamic characteristics

[0005] To sum up, there is currently no velocity measurement method based on the current ultrasonic particle imaging hardware equipment, which can overcome the limitation of excessive particle displacement deviation under the condition of high flow velocity, and obtain the two-dimensional flow field distribution under the condition of large fluid velocity.

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