CN109363719B - Ultrasonic out-of-order color Doppler optimized scanning method - Google Patents

Abstract

A digital ultrasonic frequency doubling and sequencing method is characterized in that echo signals are received and sequenced in an optimized sequence by arranging array elements, so that the space interval corresponding to two adjacent scanning lines in a time sequence is larger, and signal interference generated in the subsequent beam forming process is avoided. The invention can avoid echoes of other transmitting signals as much as possible, thereby reducing interference and greatly improving image quality.

Description

Ultrasonic out-of-order color Doppler optimized scanning method

Technical Field

The invention relates to a technology in the field of medical equipment control, in particular to an ultrasonic disorder color Doppler optimization scanning method.

Background

In the existing ultrasonic color doppler imaging, continuous emission is performed for multiple times at a fixed pulse repetition frequency (prf) interval, and the movement speed of a tissue is obtained by solving the phase shift of an echo signal, wherein the echo signal acquires the echo signal through an array element under the corresponding receiving delay of an emission signal and obtains the information of one scanning line through beam forming. Because of the time required for tissue to absorb the echoes of ultrasound, the minimum value of the receive delay is the period of the pulse repetition frequency, i.e., 1/prf. In actual detection, when the receiving delay setting is close to the lower limit, it is easy to happen that the receiving array element receives echo signals transmitted last several times at a certain preset delay, i.e. reverberation from a reflector in depth outside the image depth. This phenomenon is not noticeable when the echo signal is strong, but when detecting the moving velocity of a fine object such as blood flow, the reception of other echo signals causes the image to generate interference such as a virtual image and an artifact.

As a conventional technique, chinese patent document No. CN108472013A discloses an ultrasonic observation apparatus for generating doppler information based on a plurality of scan data acquired by sequential alternate scanning in which ultrasonic waves are sequentially transmitted in a plurality of depth directions and the ultrasonic waves are repeatedly transmitted in the order of the transmission, the ultrasonic observation apparatus including: a calculation unit that compares first scan data obtained by transmitting ultrasonic waves in a depth direction in which scanning is performed first in sequential alternate scanning with second scan data obtained by transmitting ultrasonic waves in the same depth direction as the depth direction in which scanning is performed first and obtained by transmitting ultrasonic waves for a second time; and a sequential alternate scanning control unit for controlling the repetition frequency based on the calculation result of the calculation unit. The technology adopts a variable prf period to receive the echo, and can overcome the reverberation phenomenon to a certain extent. But this technique is complex to implement and requires additional hardware support.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an ultrasonic disorder color Doppler optimization scanning method, which avoids echoes of other emission signals as much as possible by optimizing the scanning sequence of different ultrasonic color Doppler scanning lines so as to reduce interference and greatly improve image quality.

The invention is realized by the following technical scheme:

the array elements are arranged to receive and sequence the echo signals in an optimized sequence, so that the space interval corresponding to two adjacent scanning lines in the time sequence is larger, and the signal interference generated in the subsequent beam forming process is avoided.

The optimized sequence is as follows: sequentially selecting spatial position distance:

①

the scanning lines in the space range are used as the next scanning line to be scanned, and the space spacing sum of all the scanning lines in one batch is

Wherein: n is the number of all scan lines and n is an even number.

②

Or

One scanning line in any one as the next oneThe scanning is carried out, and the spatial spacing sum of all the scanning lines under one batch is

Wherein: n is the number of all scan lines and n is an odd number.

The order is as follows: and controlling the matrix selection network to perform channel adjustment of echo signals in the sequence corresponding to the received scanning lines so as to meet the sequence required by focusing processing.

Technical effects

Compared with the prior art, the invention ensures that the interval of the echo signals of the scanning lines adjacent to the time sequence is farther in space by adjusting the sequence of transmitting and receiving the echo in the ultrasonic scanning, and each scanning line can be over-focused to obtain a clearer signal so as to obtain a clearer image.

Drawings

FIG. 1 is a schematic diagram of a conventional scan sequence;

FIG. 2 is a schematic diagram of an exemplary scan sequence.

Detailed Description

As shown in fig. 1, the schematic diagram of the general sequential principle of four scan lines is shown, that is, color doppler scanning is performed in a general sequential manner, and the obtained echo data is subjected to batch data processing, wherein the interval between each scan line is 1/prf. The conventional scanning sequence is shown in fig. 2A, i.e. according to the scanning line numbers { #0, #1, #2, #3}, the spatial interval between two adjacent scanning lines is d.

As shown in fig. 2B, the present embodiment adopts an optimized sequence for spatial position selection:

when the number of scanning lines is 4, the first one #0 is determined and then selected to have a distance of

The spatial range, i.e. any one of the spatial distances d, 2d, 3d is scanned as the next one, and the sum of the spatial distances of all the scan lines under one batch is 8 d.

The updated scanning order is used to obtain the echo signal shown in fig. 2, and the order is selected to satisfy: scanning and echo signal receiving are carried out by setting scanning lines according to a mode of { #0, #2, #1, #3} in sequence. The space intervals of the scanning lines adjacent to each other in time sequence are 2d, 1d, 2d and 3d, and reach 2d on average, namely twice the scanning line interval.

Accordingly, when there are 9 scan lines, the selection method is: the first root #0 is selected to be at a distance of

Or

One scan line in any of these, i.e., either one of distances 4d or 5d, is scanned as the next one, and the sum of the spatial spacings of all scan lines for one batch is 40d, one of the corresponding sequences obtained is { #0, #5, #1, #6, #2, #7, #3, #8, #4 }.

According to the setting conditions of different scanning lines, the scanning delay can be correspondingly adjusted in the following way to obtain the corresponding average interval

By the mode, the scanning lines in one prf period are ensured to appear once respectively, and the space intervals of the scanning lines adjacent to the time sequence are ensured to be basically consistent and several times of the line intervals scanned in sequence, which is specifically as follows:

compared with the prior art, the method can realize the elimination of the reverberation signal through the simple and convenient mode.

The foregoing embodiments may be modified in many different ways by those skilled in the art without departing from the spirit and scope of the invention, which is defined by the appended claims and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (1)

1. A digital ultrasonic frequency doubling and sequencing method is characterized in that echo signals are received and sequenced in an optimized sequence by arranging array elements, so that the space interval corresponding to two adjacent scanning lines in a time sequence is larger, and signal interference generated in the subsequent beam forming process is avoided;

the optimized sequence is as follows: sequentially selecting spatial position distance:

①

the scanning lines in the space range are used as the next scanning line to be scanned, and the space spacing sum of all the scanning lines in one batch is

Wherein:nis the number of all scanning linesnIs even number, d is space interval between two adjacent scanning lines;

②

one scanning line in any one of the scanning lines is used as the next scanning line to be scanned, and the sum of the space intervals of all the scanning lines in one batch is

Wherein:nis the number of all scanning linesnIs odd;

the order is as follows: and controlling the matrix selection network to perform channel adjustment of echo signals in the sequence corresponding to the received scanning lines so as to meet the sequence required by focusing processing.

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