KR101441195B1 - Ultrasonic diagnosis device and signal processing device calculating spectrum, centroid and method for calculating spectrum centroid - Google Patents

Abstract

The present invention relates to an ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus of the present invention is a device for calculating the spectral center of a received signal based on an ultrasonic transducer, a transmitter for supplying a signal to the ultrasonic transducer, a receiver for receiving a signal from the ultrasonic transducer, And a spectral centric calculator. The spectral center calculator calculates the spectral center based on the values of the samples of the received signal and the values of some samples.

Description

TECHNICAL FIELD [0001] The present invention relates to an ultrasound diagnostic apparatus and a signal processing apparatus for calculating a spectral center, and a spectral-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic apparatus, and more particularly, to an ultrasonic diagnostic apparatus and a signal processing apparatus for calculating a spectral center, and a spectral center calculation method.

In the field of diagnostic medicine, ultrasonic diagnostic devices are widely used. The ultrasonic diagnostic apparatus emits ultrasonic waves to a human body and provides images such as a B mode (Brightness Mode) image using ultrasonic waves reflected from a human body. Compared to other diagnostic devices, the ultrasonic diagnostic device has the advantage of low side effects and low manufacturing costs.

A conventional ultrasonic diagnostic apparatus displays the diagnosis result only in the B mode image. However, ultrasonic waves reflected from the human body include various information about the human body in addition to the information used in the B mode image. One of the various information about the human body that the reflected ultrasonic waves contain is the spectrum centroid. When the spectral center of the ultrasonic wave reflected from the human body is calculated according to the transmission distance (depth) of the ultrasonic wave, the movement of the spectral center due to the frequency selective attenuation can be measured. Spectral centered movement provides useful information about the human body from which the ultrasound is emitted.

It is an object of the present invention to provide an ultrasonic diagnostic apparatus, a signal processing apparatus, and a spectral center calculation method in which the time consumed in the calculation of the spectral center is reduced.

An ultrasonic diagnostic apparatus according to an embodiment of the present invention includes an ultrasonic transducer; A transmitter for supplying a signal to the ultrasonic transducer; A receiver for receiving a signal from the ultrasonic transducer; And a spectral center calculator configured to calculate a spectral center of the received signal based on a received signal output from the receiver, wherein the spectral center calculator is configured to calculate a spectral center based on values of samples of the received signal and values of some samples To calculate the spectral center.

In an embodiment, the spectral center calculator comprises: a first momentum calculator configured to calculate a first momentum based on the values of the samples; A second momentum calculator configured to calculate a second momentum based on the values of some of the samples; And a division unit configured to divide the second momentum by the first momentum and calculate the spectral center.

In an embodiment, the first momentum calculator comprises: an absolute value calculator configured to calculate absolute values of the values of the samples; A multiplier configured to calculate the squared values of the calculated absolute values; And an adder configured to calculate a cumulative sum of the squared values.

In an embodiment, the second momentum calculator comprises: a sample selector configured to select the selected one of the samples of the received signal; An autocorrelation calculation unit configured to calculate autocorrelation values of values of some samples; A coefficient storage configured to store coefficients corresponding to the some samples; A multiplier configured to calculate the autocorrelation values and the multiplication values of the coefficients, respectively; An adder configured to calculate a cumulative sum of the multiplication values; And a divider configured to calculate a half value of the cumulative sum.

In an embodiment, the coefficient storage is configured to store some of the coefficients in time domain expanded tabs of a filter having a triangular frequency response with rising and falling intervals.

In an embodiment, the sample selector is configured to select the partial samples based on locations of the partial coefficients.

In an embodiment, the partial coefficients have values adjusted according to the values of coefficients not stored in the coefficient storage.

According to an embodiment, the spectral center calculator may further include a coefficient group selection unit, wherein the coefficient storage unit is configured to store a plurality of coefficient groups, wherein the coefficient group selection unit selects, Wherein the coefficient storage unit is configured to output coefficients of the coefficient group selected by the coefficient group selection unit to the multiplier unit.

As an embodiment, the image processing apparatus further includes an image processor configured to perform image processing based on a received signal output from the receiver.

In an embodiment, the ultrasonic diagnostic apparatus is configured to process a B mode image.

As an embodiment, the apparatus further comprises an output unit configured to output the spectral center calculated by the spectral center calculator.

In an embodiment, the spectral center calculator is configured to calculate the spectral center in the time domain.

A spectral center calculator according to an embodiment of the present invention includes a first momentum calculator configured to calculate a first momentum based on samples of a received signal received from the outside; A second momentum calculator configured to calculate a second momentum based on some of the samples of the received signal; And a divider configured to divide the second momentum by the first momentum and calculate a spectral center of the received signal.

In an embodiment, the first momentum calculator and the second momentum calculator are configured to calculate the first momentum and the second momentum, respectively, in the time domain.

A spectral center calculation method according to an embodiment of the present invention includes: receiving a received signal from an external device; Calculating a first momentum based on the samples of the received signal; Calculating a second momentum based on some of the samples; And calculating the second center of gravity of the received signal by computing the second momentum and the first momentum.

As an embodiment, calculating the first momentum may include calculating an absolute value of a sample of the received signal; Calculating a squared value of the calculated absolute value; Calculating a cumulative sum of the calculated squared values; Calculating the absolute value, the squared value, and the cumulative sum for the next sample of the received signal if the sample is not the last sample; and if the sample is the last sample, selecting the cumulative sum as the first momentum .

As an embodiment, calculating the second momentum comprises: determining whether the sample of the received signal is a selected sample; Ignoring the sample if the sample is not the selected sample and calculating an autocorrelation value of the sample if the sample is the selected sample; Calculating a multiplication value of the calculated autocorrelation value and a corresponding one of the previously stored coefficients; Calculating a cumulative sum of the calculated multiplication values; Calculating the autocorrelation value, the squared value, and the cumulative sum if the sample is not the last sample; and if the sample is the last sample, And selecting the second momentum as the second momentum.

As an embodiment, calculating the spectral center comprises dividing the second momentum into the first momentum.

As an embodiment, calculating the first momentum and calculating the second momentum are performed in the time domain.

As an embodiment, calculating the first momentum and calculating the second momentum are performed in parallel.

According to the present invention, the spectral center is calculated in the time domain based on some of the samples received. Accordingly, there is provided an ultrasonic diagnostic apparatus and a signal processing apparatus with reduced time consumed in calculation of the spectral center, and a spectral center calculation method.

1 is a block diagram showing an ultrasonic diagnostic apparatus according to a first embodiment of the present invention.
Figure 2 shows a spectral center calculator according to an embodiment of the present invention.
3 shows an example of values of the time domain of the autocorrelation value weight function.
4 is a flowchart showing a method of calculating a spectral center according to an embodiment of the present invention.
5 is a flowchart illustrating a method of calculating a first momentum according to an embodiment of the present invention.
6 is a flowchart illustrating a method of calculating a second momentum according to an embodiment of the present invention.
7 is a block diagram showing an ultrasonic diagnostic apparatus according to a second embodiment of the present invention.
8 shows a spectral center calculator according to a second embodiment of the present invention.
9 is a block diagram showing an ultrasonic diagnostic apparatus according to a third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the technical idea of the present invention. .

1 is a block diagram showing an ultrasonic diagnostic apparatus 100 according to a first embodiment of the present invention. 1, the ultrasonic diagnostic apparatus 100 includes an ultrasonic transducer 110, a transmitter 120, a receiver 130, a transmission beamformer 140, a reception beamformer 150, a spectrum center calculator 160, And an output unit 170.

The ultrasonic transducer 110 is configured to emit ultrasonic waves toward an external target (e.g., a human body) and receive ultrasonic waves reflected from an external target. The ultrasonic transducer 110 includes a plurality of acoustic elements 111. Each of the plurality of acoustic elements 111 is configured to emit an ultrasonic wave to an external target in accordance with a signal transmitted from the transmitter 120 and to convert the ultrasonic wave reflected from an external target into an electric signal and transmit the converted signal to the receiver 130.

The transmitter 120 is configured to output a signal to the ultrasonic transducer 120. The transmitter 120 includes a transmit beamformer 140, a digital-to-analog converter 123, a filter 125, an amplifier 127 and a multiplexer 129.

The transmission beamformer 140 can control the signal so that the ultrasonic waves emitted from the ultrasonic transducer 110 converge on a predetermined focal point on a predetermined scan line.

The digital-to-analog converter 123 is configured to convert a signal output from the transmission beamformer 140 into an analog signal. The filter 125 is configured to filter the output signal of the digital-to-analog converter 125 to remove noise. The filter 125 may comprise a low pass filter.

The amplifier 127 is configured to amplify the output signal of the filter 125. The multiplexer 129 is configured to transmit the output signal of the amplifier 127 to at least one selected one of the plurality of acoustic elements 111 of the ultrasonic transducer 110.

The receiver 130 is configured to transmit a signal output from the ultrasonic transducer 110 to the reception beamformer 150. The receiver 130 includes a switch 131, an amplifier 133, a filter 135, an analog-to-digital converter 137 and a receive beamformer.

The switch 131 may be turned off during the transmission interval of the ultrasonic transducer 110 and may be turned on during the reception interval. The switch 131 may block a signal transmitted from the transmitter 120 to the ultrasonic transducer 110 from entering the receiver 130.

The amplifier 133 is configured to amplify the output signal of the switch 131. The amplifier 133 may include at least one of a Low Noise Amplifier (LNA), a Voltage Controlled Amplifier (VCA), and a Programmable Gain Amplifier (PGA).

The filter 135 is configured to filter the output signal of the amplifier 133 to remove noise. The filter 135 may comprise a low pass filter. The analog-to-digital converter 137 is configured to convert the output signal of the filter 135 into a digital signal. The reception beam former 150 may control an output signal of the analog-to-digital converter 137 so that the received signal is divided into channels of the ultrasonic transducer 110. [

The spectral center calculator 160 is configured to calculate a spectral centroid of the ultrasound reflected from an external target (e.g., a human body) based on the output signal of the receive beamformer 150. For example, the spectral center calculator 160 may calculate the spectral center based on some samples of the samples of the signal output from the receive beamformer 150. The spectral center calculator 160 can calculate the spectral center in the time domain.

The output unit 170 is configured to output a signal output from the spectrum center calculator 160 to the outside. For example, the output device 170 may include at least one of various output means such as a monitor, an LCD device, an AMOLED display device, a printer, a communication modem, and the like.

Illustratively, the ultrasonic diagnostic apparatus 100 may be applied to various diagnostic apparatuses such as an ultrasonic diagnostic apparatus for human body as well as an ultrasonic diagnostic apparatus for non-destructive examination. The ultrasonic diagnostic apparatus 100 can be applied and applied not only to ultrasonic waves but also various devices that emit waves and receive reflected waves according to the emitted waves.

FIG. 2 shows a spectral center calculator 160 according to an embodiment of the present invention. 1 and 2, the spectral center calculator 160 includes a first momentum calculator 161, a second momentum calculator 162, and a divider DU.

The first momentum calculator 161 is configured to calculate a first momentum m0 based on the samples of the signals output from the receive beamformer 150. [ The first momentum calculator 161 includes an absolute value calculator A1, a multiplier MU1, and an adder S1.

The absolute value calculation unit A1 is configured to calculate the absolute values of the samples of the signal received from the reception beamformer 150, respectively.

The multiplying unit MU1 is configured to calculate square values of the absolute values of the samples output from the absolute value unit A1, respectively.

The adder S1 is configured to calculate a cumulative sum of the squared values output from the multiplier MU1. The output value of the adder S1 may be the first momentum m0.

The absolute value calculation unit A1, the multiplier MU1, and the adder S1 are configured to sequentially perform operations of the samples sequentially received from the reception beamformer 150. [ The absolute value calculation unit A1, the multiplier MU1, and the adder S1 may have a pipeline structure or a parallel processing structure. The adder S1 can output the final cumulative sum as the first momentum m0 when the calculation of the predetermined samples is completed.

The second momentum calculator 162 is configured to calculate a second momentum m1 based on the samples of the signals output from the receive beam former 150. [ The second momentum calculator m1 includes a coefficient storage unit 163, a sample selector 164, an autocorrelation calculator 165, a multiplier MU2, an adder S2 and a divider D1 do.

The coefficient storage unit 163 is configured to store predetermined coefficients.

The sample selector 164 is configured to select some of the samples output from the receive beamformer 150. [ Illustratively, the sample selector 164 can select samples corresponding to the coefficients stored in the coefficient storage 163. [ The sample selector 164 outputs the selected sample to the autocorrelation calculator 165 and can ignore the unselected samples.

The autocorrelation calculation unit 165 is configured to calculate an autocorrelation value of the selected sample.

The multiplier MU2 calculates the multiplication value of the coefficient corresponding to the sample selected by the sample selector 164 and the autocorrelation value output from the autocorrelation calculator 165 among the coefficients stored in the coefficient storage 163 .

The adder S2 can calculate the cumulative sum of the multiplication values output from the multiplier MU2.

The divider D1 is configured to calculate 1/2 of the cumulative sum output from the adder S2. The output of the divider D1 may be the second momentum m1.

The sample selector 164, the autocorrelation calculator 165, the multiplier MU2, and the adder S2 are configured to sequentially perform operations of the samples sequentially received from the reception beamformer 150. [ The sample selector 164, the autocorrelation calculator 165, the multiplier MU2, and the adder S2 may have a pipeline structure or a parallel processing structure. The adder S2 can output the final cumulative sum to the divider D1 when the calculation of the predetermined samples is completed.

The division unit DU can divide the second momentum m1 into a first momentum m0. The output of the division unit DU may be the center frequency of the ultrasonic wave received by the ultrasonic transducer 110.

Hereinafter, the process of calculating the spectral center by the spectral center calculator 160 of FIG. 2 will be described with reference to the equations.

The spectral center of a particular signal is defined by Equation (1).

The first momentum m0 of Equation 1 is summarized as Equation 2 in the discrete signal.

In Equation 2, the variable N indicates the number of samples. The function X (k) indicates a discrete Fourier transform (DFT) of the signal x (n). The function X ^* (k) and the function x ^* (n) refer to the complex conjugate function of the function X (k) and the function x (k), respectively. The integral operation of Equation (1) is replaced with a sigma operation in Equation (2). Df in Equation (1) is replaced by 1 / N in Equation (2).

The second momentum m1 of Equation (1) is summarized as Equation (3) in the digital signal.

In Equation (3), the variable N indicates the number of samples. The function X (k) indicates a discrete Fourier transform (DFT) of the signal x (n). The function X ^* (k) and the function x ^* (n) refer to the complex conjugate function of the function X (k) and the function x (k), respectively. The integral operation of Equation (1) is replaced by a sigma operation in Equation (3). Df in Equation (1) is replaced by 1 / N in Equation (3). F in Equation 1 is replaced by k / N in Equation 2 and corresponds to the frequency of the kth point of the discrete Fourier transform.

For the expansion of equation (3), the function P (k) is defined in equation (4).

Based on Equations (3) and (4), the second momentum (m1) can be summarized as Equation (5).

In order to summarize the second momentum m1 according to an embodiment of the present invention, a new function S (k) is defined in equation (6).

Based on the function S (k) defined in equation (6), the second momentum m1 in equation (5) can be summarized as in equation (7).

In Equation (7), the second momentum m1 is summarized in the frequency domain. The product of functions in the frequency domain is developed into a convolution of functions in the time domain. Thus, in the time domain, if Parseval's Theorem is applied to the second momentum m1 in Equation 7, then the second momentum m1 is developed as in Equation 8. [

)는 원형 콘볼루션(circular convolution)을 가리킨다. 신호(x_N(n))는 신호(x(n))가 N의 주기를 갖는 주기적 신호로 변형된 신호를 가리킨다.In Equation (8), an operation symbol (

) Refers to a circular convolution. The signal x _N (n) indicates a signal in which the signal x (n) has been transformed into a periodic signal having a period of N.

In a typical ultrasonic field, the signal x (n) is a real-valued signal. Therefore, the conjugate operator of Equation (8) can be omitted. Based on this, Equation (8) can be rearranged as Equation (9).

The function r _xx (l) is a circular autocorrelation function of the signal x (n). The function s (l) indicates the weighting applied to the autocorrelation function r _xx (l).

As defined in Equation (6), the function s (l) has a triangular-shaped frequency response that gradually increases for half a period and gradually decreases for the remaining half period. An example of the time domain values of the function s (l) is shown in FIG.

Referring to Fig. 3, the values of the function s (l) are concentrated at the beginning and end of the time index. In the middle part of the time index, the function s (l) has values close to zero.

The second momentum m1 is expressed as a cumulative sum of the product of the function s (l) and the autocorrelation function r _xx (l), as described in equation (9). As shown in Fig. 3, in most areas of the time index, the value of the function s (l) has a value close to zero. That is, the second momentum m1 can be approximated by a cumulative sum of the product of the function s (l) and the autocorrelation function (r _xx (l)) in some area at the beginning and end of the time index.

The calculation of the second momentum m1 in Equation (9) may be performed by the second momentum calculator 162. [ The coefficient storage unit 163 may store coefficients used for the calculation of the second momentum m1 among the coefficients of the function s (l) of Fig. For example, the coefficient storage unit 163 may store the coefficients at the start and end of the time index among the coefficients of the function s (l).

The sample selector 164 can select samples corresponding to the coefficients stored in the coefficient storage unit 163 among the samples of the signal received from the reception beamformer 150. [ The unselected samples are ignored, and the selected samples can be output to the autocorrelation calculation unit 165. [

The autocorrelation calculation unit 165 may calculate the autocorrelation value of the selected samples. The multiplier MU2 may multiply the coefficient of the coefficient storage 163 and the autocorrelation value of the autocorrelation calculator 165 to calculate a multiplication value. The adder S2 calculates the cumulative sum of the multiplication values, and the divider D1 outputs the half value of the cumulative sum as the second momentum m1.

Generally, autocorrelation calculation requires a complicated calculation process and takes a long time. The spectral center calculator 160 according to the embodiment of the present invention performs calculations using the filter described in Equation (6). The filter of Equation (6) has a meaningful value only in a part of the time domain. Thus, in the time domain, autocorrelation of most of the samples received from the receive beamformer 150 is not performed, only autocorrelation of some samples is performed. Therefore, a method of calculating the center of the spectrum faster than a conventional spectral center calculation method while performing autocorrelation of samples is provided.

Illustratively, the selected coefficients stored in the coefficient storage 163 may be adjusted to compensate for the values of the non-selected coefficients.

4 is a flowchart showing a method of calculating a spectral center according to an embodiment of the present invention. 1, 2, and 4, in step S10, a received signal is received. The received signal may be transmitted to the spectral center calculator 160 via the receiver 130.

In step S20, a first momentum m0 is calculated based on the samples of the received signal. The first momentum m0 may be calculated by the first momentum calculator 161. [

In step S30, a second momentum is calculated based on some of the samples of the received signal. The second momentum m1 may be calculated by the second momentum calculator 162. [

Steps S20 and S30 may be performed in parallel. That is, while the first momentum calculator 161 calculates the first momentum m0, the second momentum calculator 162 may calculate the second momentum.

In step S40, the spectral center is calculated by dividing the second momentum by the first momentum.

5 is a flowchart illustrating a method of calculating a first momentum m0 according to an embodiment of the present invention. 2 and 5, in step S110, the absolute value of the sample signal is calculated. The absolute value of the sample signals can be performed by the absolute value calculation section A1.

In step S120, the squared value of the calculated absolute value is calculated. The calculation of the squared value can be performed by the multiplier MU1.

In step S130, a cumulative sum of the calculated squared values is calculated. The cumulative sum is performed by the adder S1.

In step S140, it is determined whether the calculated sample is the last sample. If the calculated sample is not the last sample, the operation for the next sample is performed from step S110. If the calculated sample is the last sample, in step S150, the calculated cumulative sum is output as the first momentum m0.

6 is a flowchart illustrating a method of calculating a second momentum m1 according to an embodiment of the present invention. Referring to FIGS. 2 and 6, in step S210, it is determined whether the received sample is a selected sample. If the received sample is not the selected sample, the received sample may be ignored. If the received sample is the selected sample, step S220 is performed. The operation of determining whether the selected sample is the received sample can be performed by the sample selector 164.

In step S220, the autocorrelation value of the selected sample is calculated. The calculation of the autocorrelation value may be performed by the autocorrelation calculation unit 165. [

In step S230, a multiplication value of the calculated autocorrelation value and a corresponding one of the previously stored coefficients is calculated. The multiplier MU2 may multiply the output of the autocorrelation calculator 165 and the output of the coefficient storage 163 to calculate a multiplication value.

In step S240, a cumulative sum of the calculated multiplication values is calculated. The calculation of the cumulative sum may be performed by the adder S2.

In step S250, it is determined whether the received sample is the last sample. If the received sample is not the last sample, the operation of the next sample is performed from step S210. If the received sample is the last sample, in step S260, the calculated cumulative sum is output as the second momentum m1. For example, a half value of the calculated cumulative sum may be output as the second momentum m1.

FIG. 7 is a block diagram showing an ultrasonic diagnostic apparatus 200 according to a second embodiment of the present invention. 7, the ultrasonic diagnostic apparatus 200 includes an ultrasonic transducer 210, a transmitter 220, a receiver 230, a transmission beamformer 240, a reception beamformer 250, a spectrum center calculator 260, An output device 270, and an input device 280.

1, the ultrasound diagnostic apparatus 200 further includes an input unit 280, and the spectrum center calculator 260 further includes a coefficient group selection unit 266. [

The input device 280 may include at least one of various input means such as a keyboard, a microphone, a touch pad, a modem, etc. for receiving a signal from the outside. For example, the input unit 280 may transmit the received information to the coefficient group selection unit 266 according to the user's selection.

8 shows a spectral center calculator 260 according to a second embodiment of the present invention. 7 and 8, the spectral center calculator 260 includes a first momentum calculator 261, a second momentum calculator 262, and a divider DU. Compared with the second momentum calculator 162 of FIG. 2, the second momentum calculator 262 further includes a coefficient group selector 266. [

The coefficient storage unit 263 may store a plurality of coefficient groups C. Each of the plurality of coefficient groups C may store values of some of the coefficients shown in FIG. The number of coefficients stored by the plurality of coefficient groups (C) may be different from each other. The coefficient storage unit 263 may select one of the plurality of coefficient groups C and output the coefficients of the selected coefficient group in response to the signal transmitted from the coefficient group selection unit.

The sample selection unit 264 can select samples corresponding to the coefficients of the selected coefficient group in response to the signal transmitted from the coefficient group selection unit 266. [

Based on the information received via the input device 280, the number of coefficients output by the coefficient storage unit 263 is adjusted. That is, the spectral center resolution (or accuracy) computed by the spectral center calculator 260 may be varied based on the information received via the input device 280.

9 is a block diagram showing an ultrasonic diagnostic apparatus 300 according to a third embodiment of the present invention. 9, the ultrasonic diagnostic apparatus 300 includes an ultrasonic transducer 310, a receiver 330, a transmitter 320, a transmission beamformer 340, a reception beamformer 350, a spectrum center calculator 360, An output unit 370, and an image processor 380.

1, the ultrasound diagnostic apparatus 300 further includes an image processor 380. The ultrasound diagnostic apparatus 300 shown in FIG. The image processor 380 may perform image processing based on the samples received via the receiver 330. For example, the image processor 380 may generate a B mode image based on the received samples. The generated B mode image may be output through an output device 370. [

That is, the ultrasonic diagnostic apparatus 300 may have both a function of outputting a B-mode image and a function of calculating a spectrum center. The ultrasonic diagnostic apparatus 300 may selectively enable or disable one of the output function of the B mode image and the calculation function of the spectral center.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be determined by the claims equivalent to the claims of the present invention as well as the claims of the following.

100, 200, 300; Ultrasonic diagnostic equipment
110, 210, 310; An ultrasonic transducer 120, 220, 320; transmitter
130, 230, 330; Receivers 160, 260, 360; Spectrum center calculator
170, 270, 370; An output device 280; Input device
380; Image processor
161, 261; A first momentum calculator 162, 262; The second momentum calculation unit
163, 263; Coefficient storage units 164 and 264; The sample selector
165, 265; An autocorrelation calculation unit 266; The coefficient group selection unit
A1; Absolute value calculation units MU1 and MU2; Multiplier
S1, S2; Adders D1, DU; Divider

Claims (20)

Ultrasonic transducer;
A transmitter for supplying a signal to the ultrasonic transducer;
A receiver for receiving a signal from the ultrasonic transducer; And
And a spectral center calculator configured to calculate a spectral center of the received signal based on a received signal output from the receiver,
Wherein the spectral center calculator calculates a first momentum using values of samples of the received signal and calculates a second momentum using values of some of the samples of the received signal, And to calculate the spectral center based on the second momentum,
Wherein the spectral center calculator comprises:
A first momentum calculator configured to calculate the first momentum based on the values of the samples;
A second momentum calculator configured to calculate the second momentum based on values of some of the samples; And
And a divider configured to divide the second momentum by the first momentum to calculate the spectral center,
Wherein the first momentum calculator comprises:
An absolute value calculator configured to calculate absolute values of the values of the samples;
A multiplier configured to calculate the squared values of the calculated absolute values; And
And an adder configured to compute a cumulative sum of the squared values. delete delete Ultrasonic transducer;
A transmitter for supplying a signal to the ultrasonic transducer;
A receiver for receiving a signal from the ultrasonic transducer; And
And a spectral center calculator configured to calculate a spectral center of the received signal based on a received signal output from the receiver,
Wherein the spectral center calculator calculates a first momentum using values of samples of the received signal and calculates a second momentum using values of some of the samples of the received signal, And to calculate the spectral center based on the second momentum,
Wherein the spectral center calculator comprises:
A first momentum calculator configured to calculate the first momentum based on the values of the samples;
A second momentum calculator configured to calculate the second momentum based on values of some of the samples; And
And a divider configured to divide the second momentum by the first momentum to calculate the spectral center,
Wherein the second momentum calculator comprises:
A sample selector configured to select the selected one of the samples of the received signal;
An autocorrelation calculation unit configured to calculate autocorrelation values of values of some samples;
A coefficient storage configured to store coefficients corresponding to the some samples;
A multiplier configured to calculate the autocorrelation values and the multiplication values of the coefficients, respectively;
An adder configured to calculate a cumulative sum of the multiplication values; And
And a divider configured to calculate a half value of the cumulative sum. 5. The method of claim 4,
Wherein the coefficient storage unit is configured to store some coefficients among coefficients obtained by expanding a frequency response of a triangle having a rising section and a falling section in a time domain. 6. The method of claim 5,
And the sample selector is configured to select the partial samples based on positions in the time domain of the partial coefficients. 6. The method of claim 5,
Wherein the partial coefficients have values adjusted to compensate for an error of the second momentum generated as the values of the remaining coefficients except the partial coefficients among the coefficients are not used in the second momentum calculator. 5. The method of claim 4,
Wherein the spectral center calculator further comprises a coefficient group selector,
Wherein the coefficient storage unit is configured to store a plurality of coefficient groups,
Wherein the coefficient group selection unit is configured to select one of the plurality of coefficient groups in response to a signal received from the outside according to a user's selection,
Wherein the coefficient storage unit is configured to output coefficients of a coefficient group selected by the coefficient group selection unit to the multiplier. The method according to claim 1 or 4,
And an image processor configured to perform image processing based on a received signal output from the receiver. 10. The method of claim 9,
Wherein the ultrasound diagnostic apparatus is configured to process the B-mode image. The method according to claim 1 or 4,
And an output unit configured to output the spectral center calculated by the spectral center calculator. The method according to claim 1 or 4,
Wherein the spectral center calculator is configured to calculate the spectral center in the time domain. A first momentum calculator configured to calculate a first momentum based on samples of a received signal received from the outside;
A second momentum calculator configured to calculate a second momentum based on some of the samples of the received signal; And
And a divider configured to divide the second momentum by the first momentum and calculate a spectral center of the received signal,
Wherein the first momentum calculator and the second momentum calculator are configured to calculate the first momentum and the second momentum, respectively, in the time domain,
Wherein the first momentum calculator comprises:
An absolute value calculator configured to calculate absolute values of the values of the samples;
A multiplier configured to calculate the squared values of the calculated absolute values; And
And an adder configured to compute a cumulative sum of the squared values. A first momentum calculator configured to calculate a first momentum based on samples of a received signal received from the outside;
A second momentum calculator configured to calculate a second momentum based on some of the samples of the received signal; And
And a divider configured to divide the second momentum by the first momentum and calculate a spectral center of the received signal,
Wherein the first momentum calculator and the second momentum calculator are configured to calculate the first momentum and the second momentum, respectively, in the time domain,
Wherein the second momentum calculator comprises:
A sample selector configured to select the selected one of the samples of the received signal;
An autocorrelation calculation unit configured to calculate autocorrelation values of values of some samples;
A coefficient storage configured to store coefficients corresponding to the some samples;
A multiplier configured to calculate the autocorrelation values and the multiplication values of the coefficients, respectively;
An adder configured to calculate a cumulative sum of the multiplication values; And
And a divider configured to calculate a half value of the cumulative sum. Receiving a received signal from an external device;
Calculating a first momentum based on the samples of the received signal;
Calculating a second momentum based on some of the samples; And
Calculating the second momentum and the first momentum to calculate a spectral center of the received signal,
Wherein the step of calculating the first momentum comprises:
Calculating an absolute value of a sample of the received signal;
Calculating a squared value of the calculated absolute value;
Calculating a cumulative sum of the calculated squared values; And
Calculating the absolute value, the squared value, and the cumulative sum for the next sample of the received signal if the sample is not the last sample, and if the sample is the last sample, selecting the cumulative sum as the first momentum / RTI > wherein the method comprises the steps of: delete Receiving a received signal from an external device;
Calculating a first momentum based on the samples of the received signal;
Calculating a second momentum based on some of the samples; And
Calculating the second momentum and the first momentum to calculate a spectral center of the received signal,
Wherein the step of calculating the second momentum comprises:
Determining whether a sample of the received signal is a selected sample;
Ignoring the sample if the sample is not the selected sample and calculating an autocorrelation value of the sample if the sample is the selected sample;
Calculating a multiplication value of the calculated autocorrelation value and a corresponding one of the previously stored coefficients;
Calculating a cumulative sum of the calculated multiplication values; And
Calculating the autocorrelation value, the squared value, and the cumulative sum if the sample is not the last sample; and if the sample is the last sample, determining again for the next sample of the received signal and if the sample is the last sample, And selecting the second momentum as the second momentum. 18. The method according to claim 15 or 17,
Wherein the calculating the spectral center comprises:
And dividing the second momentum by the first momentum. 18. The method according to claim 15 or 17,
Wherein the calculating the first momentum and the second momentum are performed in the time domain. 18. The method according to claim 15 or 17,
Wherein the step of calculating the first momentum and the step of calculating the second momentum are performed in parallel.

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