Specific embodiment
Hereinafter, the present invention will be described in detail with reference to various embodiments shown in the accompanying drawings.But these embodiments are not
The limitation present invention, structure that those skilled in the art are made according to these embodiments, method or change functionally
It changes and is included within the scope of protection of the present invention.
It should be noted that present invention is mainly applied to ultrasonic device, correspondingly, the determinand can be test serum,
It is not described in detail herein.
As shown in connection with fig. 1, the module diagram of Doppler Imaging systems;During pulse Doppler wall filtering;
Emit pulse signal into tissue by probe, the pulse signal reflected to form in tissue ultrasonic signal via
The different primitives of probe transducers are changed into electric analoging signal, are amplified by preceding amplification module, then are converted by A/D D/A converter module
For digital signal;The digital signal of each difference primitive passes through Beam synthesis module, synthesizes radiofrequency signal;Radiofrequency signal is passed through
After the quadrature demodulation of fixed frequency, quadrature demodulation result i/q signal is sent into corresponding processing module.
During above-mentioned pulse Doppler wall filtering;Emit scanning repetition rate PRF, the launching centre frequency of pulse signal
F0 is that systemic presupposition numerical value needs to do quadrature demodulation, institute by low-pass filter during carrying out Beam synthesis to digital signal
Demodulation bandwidth B _ the iq for stating low-pass filter is also systemic presupposition threshold value.
As shown in connection with fig. 2, traditional pulse Doppler (PW) mode imaging need to pass through following process:
In door door sampling module, the signal sampling point in sampling gate is cut, then ask all sampled points are cut
It is average, it is sent into subsequent wall filtering module, wall filtering is generally high-pass filter, is mainly used to consider on slow time orientation except letter
The tissue signal of low-speed motion in number, conventional method have low order FIR mode filter, IIR mode filter and polynomial regression filtering
Device.In these filters, the performance of projection initialization iir filter and polynomial regression filter have stopband attenuation it is big,
The advantages that intermediate zone is narrow and does not lose data, wherein the stopband cutoff frequency of projection initialization iir filter is more flexible and changeable.
Signal after wall filtering is fed to subsequent FFT energy computation module and two-channel separation module.
FFT energy computation module does Fast Fourier Transform (FFT) (FFT) to the signal after wall filtering, obtains each frequency displacement point
The energy size of amount, then log-compressed is carried out by dynamic range compression module, it finally carries out frequency spectrum and shows.
The positive and negative frequency spectrum of signal is mainly carried out left and right acoustic channels separation by two-channel separation module, is converted into using rate and is
Sample rate needed for system sound card, finally carries out audio broadcasting.
As shown in connection with fig. 3, Fig. 3 is the flow chart of pulse Doppler wall filtering processing method in an embodiment of the present invention,
The described method includes:
S1, the corresponding I/Q signal of N number of sampled point is obtained in every echo-signal, to form each echo-signal
Corresponding I/Q signal sequence;
In a specific example of the invention, for the convenience of description, by the corresponding IQ of sampled point N number of in every echo-signal
Signal indicates that (x, y) indicates the coordinate of sampled point respectively with IQ (x, y).
Under normal conditions, sampled in corresponding echo-signal according to sampling gate size, the sampling gate size with
SV is indicated.
Correspondingly, i is positive integer for i-th of echo-signal, corresponding I/Q signal sequence be may be expressed as:
{IQ(1,i),IQ(2,i),IQ(3,i),….IQ(N,i)}
Wherein, N=2*SV/c*fs, fs are sample frequency.
Further, in an embodiment of the present invention, the method also includes:
S2, on slow time orientation, FFT transform is done to each I/Q signal sequence respectively, to obtain N group FFT transform
Sequence.
In a specific example of the invention, M memory space is preset, each memory space is for storing one group of I/Q signal sequence
Column, successively storage obtains M group I/Q signal sequence by the way of first in first out;After M memory space whole storing data, under
After one I/Q signal sequence needs to wait for the output of the I/Q signal sequence in the memory space of front end or removes, then stored.
In the specific embodiment of the invention, on slow time orientation, chooses M group I/Q signal sequence and does FFT transform,
M group I/Q signal sequence is successively are as follows:
{ IQ(1,i),IQ(2,i),IQ(3,i),…,IQ(N,i)}
{ IQ(1,i+1),IQ(2,i+1),IQ(3,i+1),…,IQ(N,i+1)}
{ IQ(1,i+2),IQ(2,i+2),IQ(3,i+2),…,IQ(N,i+2)}
……
{ IQ(1,i+M-1),IQ(2,i+M-1),IQ(3,i+M-1),…,IQ(N,i+M-1)}
Data of the M group I/Q signal sequence on identical column direction are obtained respectively, form the slow time change sequence of N group, and right
It does FFT transform, to obtain N group FFT transform sequence;
Correspondingly, the slow time series of N group of composition is successively are as follows:
{ IQ(1,i),IQ(1,i+1),IQ(1,i+2),…,IQ(1,i+M-1)}
{ IQ(2,i),IQ(2,i+1),IQ(2,i+2),…,IQ(2,i+M-1)}
{ IQ(3,i),IQ(3,i+1),IQ(3,i+2),…,IQ(3,i+M-1)}
……
{ IQ(N,i),IQ(N,i+1),IQ(N,i+2),…,IQ(N,i+M-1)}
After doing FFT transform to the above-mentioned slow time-varying sequence of N group, N group FFT change sequence is obtained successively are as follows:
{ IQ_fft(1,i),IQ_fft(1,i+1),IQ_fft(1,i+2),…,IQ_fft(1,i+M-1)}
{ IQ_fft(2,i),IQ_fft(2,i+1),IQ_fft(2,i+2),…,IQ_fft(2,i+M-1)}
{ IQ_fft(3,i),IQ_fft(3,i+1),IQ_fft(3,i+2),…,IQ_fft(3,i+M-1)}
……
{ IQ_fft(N,i),IQ_fft(N,i+1),IQ_fft(N,i+2),…,IQ_fft(N,i+M-1)}
Further, in an embodiment of the present invention, the method also includes:
S3, on fast time orientation, the FFT transform sequence described in every group is filtered respectively, with obtain multiple groups filter
Wave conversion sequence.
The step S3 is specifically included:
P1, data of the N group FFT transform sequence on identical column direction, transform sequence before composition M group filters are obtained respectively;
In the specific embodiment of the invention, the M group of acquisition filters preceding transform sequence successively are as follows:
{ IQ_fft(1,i),IQ_fft(2,i),IQ_fft(3,i),…,IQ_fft(N,i)}
{ IQ_fft(1,i+1),IQ_fft(2,i+1),IQ_fft(3,i+1),…,IQ_fft(N,i+1)}
{ IQ_fft(1,i+2),IQ_fft(2,i+2),IQ_fft(3,i+2),…,IQ_fft(N,i+2)}
……
{ IQ_fft(1,i+M-1),IQ_fft(2,i+M-1),IQ_fft(3,i+M-1),…,IQ_fft(N,i+M-1)}
Further, the step S3 further include:
P2, according to preset threshold speed, the repetition scanning frequency of initial transmissions signal, initial transmissions signal center frequency
Rate does quadrature demodulation to echo-signal to generate the demodulation bandwidth of the low-pass filter used during I/Q signal, described in acquisition
The corresponding frequency displacement cutoff frequency of pre-set velocity threshold value.
In an of the invention specific example, the corresponding frequency displacement cutoff frequency frej (i) of the pre-set velocity threshold value is indicated,
frej(i) = max( (i –1)/M*PRF*c/(2*abs(Vrej))-f0,-B_iq/2)
Wherein, PRF indicates the repetition scanning frequency of initial transmissions signal, and Vrej indicates pre-set velocity threshold value, and f0 is indicated just
Originate the centre frequency for penetrating signal, B_iq/2 indicate to do quadrature demodulation to echo-signal with generate use during I/Q signal it is low
Both the demodulation bandwidth of bandpass filter, abs () expression take absolute value, and max () expression takes the larger value.
Further, the step S3 further include:
P3, it is obtained on fast time orientation according to the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value to the filtering of M group
Preceding transform sequence makees the fast termporal filter being filtered;
In one of which embodiment of the invention, on fast time orientation, transform sequence does time-domain filtering before filtering to M group
Processing.
Quadrature demodulation is done according to the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value and to echo-signal to generate
Numerical relation between the demodulation bandwidth of the low-pass filter used during I/Q signal, the design fast termporal filter are
Number.
If frej (i) is not equal to-B_iq/2,
Then the upper cut off frequency B_hp and lower limiting frequency B_lp of fast termporal filter are respectively as follows:
Bp_lp = -B_iq/2;
Bp_hp = frej(i);
If frej (i) is equal to-B_iq/2,
Then the coefficient of the fast termporal filter is 0.
Further, transform sequence is filtered by the fast termporal filter respectively before M group being filtered, to obtain M
Group filtering transformation sequence.
The M group filtering transformation sequence is successively are as follows:
{IQ_fft_filterd(1,i),IQ_fft_filterd(2,i),IQ_fft_filterd(3,i),…,IQ_
fft_filterd(N,i)}
{IQ_fft_filterd(1,i+1),IQ_fft_filterd(2,i+1),IQ_fft_filterd(3,i+
1),…,IQ_fft_filterd(N, i+1)}
{IQ_fft_filterd(1,i+2),IQ_fft_filterd(2,i+2),IQ_fft_filterd(3,i+
2),…,IQ_fft_filterd(N, i+2)}
……
{IQ_fft_filterd(1,i+M-1),IQ_fft_filterd(2,i+M-1),IQ_fft_filterd(3,i+
M-1),…,IQ_fft_filterd(N,i+M-1)}
In another embodiment of the present invention, on fast time orientation, transform sequence is done at frequency domain filtering before filtering to M group
Reason.
Transform sequence does FFT transform and obtains FFT transform sequence before M group filters before filtering respectively to every group of M group;The M group
Filter preceding FFT transform sequence successively are as follows:
{IQ_fft_fast_fft(1,i),IQ_fft_fast_fft(2,i),IQ_fft_fast_fft(3,i),…,
IQ_fft_fast_fft(N,i)}
{IQ_fft_fast_fft(1,i+1),IQ_fft_fast_fft(2,i+1),IQ_fft_fast_fft(3,i+
1),…,IQ_fft_fast_fft(N, i+1)}
{IQ_fft_fast_fft(1,i+2),IQ_fft_fast_fft(2,i+2),IQ_fft_fast_fft(3,i+
2),…,IQ_fft_fast_fft(N, i+2)}
……
{IQ_fft_fast_fft(1,i+M-1),IQ_fft_fast_fft(2,i+M-1),IQ_fft_fast_fft(3,
i+M-1),…,IQ_fft_fast_fft(N,i+M-1)}
That bears in FFT transform sequence before reservation M group filters respectively does quadrature demodulation to echo-signal to generate I/Q signal mistake
Frequency between the demodulation bandwidth of the low-pass filter used in journey and the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value
Component, and other components are set to 0;
FFT transform sequence does inverse FFT transformation before the filtering retained M group, to obtain multiple groups filtering transformation sequence.
The M group filtering transformation sequence is successively are as follows:
{IQ_fft_filterd(1,i),IQ_fft_filterd(2,i),IQ_fft_filterd(3,i),…,IQ_
fft_filterd(N,i)}
{IQ_fft_filterd(1,i+1),IQ_fft_filterd(2,i+1),IQ_fft_filterd(3,i+
1),…,IQ_fft_filterd(N, i+1)}
{IQ_fft_filterd(1,i+2),IQ_fft_filterd(2,i+2),IQ_fft_filterd(3,i+
2),…,IQ_fft_filterd(N, i+2)}
……
{IQ_fft_filterd(1,i+M-1),IQ_fft_filterd(2,i+M-1),IQ_fft_filterd(3,i+
M-1),…,IQ_fft_filterd(N,i+M-1)}
Further, in an embodiment of the present invention, the method also includes:
S4, the corresponding complex-envelope of every group of filtering transformation sequence is obtained respectively, it is corresponding according to every group of filtering transformation sequence
Complex-envelope obtains total envelope signal, to show for final frequency spectrum.
In a specific embodiment of the invention, total envelope is obtained according to the corresponding complex-envelope of every group of filtering transformation sequence and is believed
During number, the average value, weighted average, minimum value, maximum of the corresponding complex-envelope of each group filtering transformation sequence can be removed
Value, boundary values and intermediate value are not described in detail herein as total envelope signal.
In following example, take the average value of the corresponding complex-envelope of each group filtering transformation sequence as total envelope signal.
Total envelope signal indicates with Spec_sum (i), then
Spec_sum(i)=fabs(IQ_fft_filterd(1,i))+fabs(IQ_fft_filterd(2,i))+…+
Fabs (IQ_fft_filterd (N, i)),
Wherein i=0,1,2 ... M, fabs () indicate the envelope for seeking every group of filtering transformation sequence plural number respectively.
Specifically, total envelope signal of acquisition is carried out dynamic range compression, finally carry out output and show, does not do herein in detail
Carefully repeat.
In conjunction with shown in Fig. 5 A- Fig. 5 D, Fig. 5 A is the two dimension obtained using traditional pulse Doppler wall filtering processing method
FFT distribution map;Fig. 5 B is using pulse Doppler wall filtering processing method Two-dimensional FFT distribution map obtained of the invention;Figure
5C is the speed spectrogram obtained using traditional pulse Doppler wall filtering processing method;Fig. 5 D is more using pulse of the invention
The general speed spectrogram strangling wall filtering processing method and obtaining.
In Fig. 5 A- Fig. 5 D, sampling gate size SV=0.01m, launching centre frequency is the sine wave of f0=5MHz, scanning weight
Complex frequency PRF is 8KHz, and scattering sub- speed is respectively 0.1m/s and 0.13m/s, Sita=0, Vrej=0.115m/s.
By Fig. 5 A- Fig. 5 D: traditional pulse Doppler's wall filtering processing method does not effectively filter out not only lower than speed
The motion information for spending scattering of threshold value impairs the information higher than threshold speed scattering, pulse Doppler of the invention
Wall filtering processing method has not only effectively removed the motion information lower than threshold speed scattering, while effectively maintaining and being higher than speed
Spend the scattering sub-information of threshold value.
As shown in connection with fig. 4, the pulse Doppler wall filtering processing system provided in an embodiment of the present invention, the system
It include: a sampling module 100, slow time-triggered protocol module 200, fast time-triggered protocol module 300, output module 400.
Door sampling module 100 in every echo-signal for obtaining the corresponding I/Q signal of N number of sampled point, with group
At the corresponding I/Q signal sequence of each echo-signal;
In a specific example of the invention, for the convenience of description, by the corresponding IQ of sampled point N number of in every echo-signal
Signal indicates that (x, y) indicates the coordinate of sampled point respectively with IQ (x, y).
Under normal conditions, sampled in corresponding echo-signal according to sampling gate size, the sampling gate size with
SV is indicated.
Correspondingly, i is positive integer for i-th of echo-signal, corresponding I/Q signal sequence be may be expressed as:
{IQ(1,i),IQ(2,i),IQ(3,i),….IQ(N,i)}
Wherein, N=2*SV/c*fs, fs are sample frequency.
Further, in an embodiment of the present invention, slow time-triggered protocol module 200 is used for: in slow time orientation, respectively
FFT transform is done to each I/Q signal sequence, to obtain N group FFT transform sequence.
In a specific example of the invention, slow time-triggered protocol module 200 presets M memory space, and each memory space is used for
One group of I/Q signal sequence is stored, successively storage obtains M group I/Q signal sequence by the way of first in first out;When M memory space
After whole storing datas, next I/Q signal sequence needs to wait for the output of the I/Q signal sequence in the memory space of front end or removes
Afterwards, it then is stored.
In the specific embodiment of the invention, on slow time orientation, slow time-triggered protocol module 200 is for choosing M group IQ letter
Number sequence does FFT transform,
M group I/Q signal sequence is successively are as follows:
{ IQ(1,i),IQ(2,i),IQ(3,i),…,IQ(N,i)}
{ IQ(1,i+1),IQ(2,i+1),IQ(3,i+1),…,IQ(N,i+1)}
{ IQ(1,i+2),IQ(2,i+2),IQ(3,i+2),…,IQ(N,i+2)}
……
{ IQ(1,i+M-1),IQ(2,i+M-1),IQ(3,i+M-1),…,IQ(N,i+M-1)}
Slow time-triggered protocol module 200 is also used to obtain data of the M group I/Q signal sequence on identical column direction respectively, forms
The slow time change sequence of N group, and FFT transform is done to it, to obtain N group FFT transform sequence;
Correspondingly, the slow time series of N group of composition is successively are as follows:
{ IQ(1,i),IQ(1,i+1),IQ(1,i+2),…,IQ(1,i+M-1)}
{ IQ(2,i),IQ(2,i+1),IQ(2,i+2),…,IQ(2,i+M-1)}
{ IQ(3,i),IQ(3,i+1),IQ(3,i+2),…,IQ(3,i+M-1)}
……
{ IQ(N,i),IQ(N,i+1),IQ(N,i+2),…,IQ(N,i+M-1)}
After slow time-triggered protocol module 200 does FFT transform to the above-mentioned slow time-varying sequence of N group, obtains N group FFT and change sequence
Leie are as follows:
{ IQ_fft(1,i),IQ_fft(1,i+1),IQ_fft(1,i+2),…,IQ_fft(1,i+M-1)}
{ IQ_fft(2,i),IQ_fft(2,i+1),IQ_fft(2,i+2),…,IQ_fft(2,i+M-1)}
{ IQ_fft(3,i),IQ_fft(3,i+1),IQ_fft(3,i+2),…,IQ_fft(3,i+M-1)}
……
{ IQ_fft(N,i),IQ_fft(N,i+1),IQ_fft(N,i+2),…,IQ_fft(N,i+M-1)}
Further, in an embodiment of the present invention, fast time-triggered protocol module 300 is used for: in fast time orientation, respectively
The FFT transform sequence described in every group is filtered, to obtain multiple groups filtering transformation sequence.
Fast time-triggered protocol module 300 is specifically used for: data of the N group FFT transform sequence on identical column direction are obtained respectively,
Form transform sequence before M group filters;
In the specific embodiment of the invention, the M group of acquisition filters preceding transform sequence successively are as follows:
{ IQ_fft(1,i),IQ_fft(2,i),IQ_fft(3,i),…,IQ_fft(N,i)}
{ IQ_fft(1,i+1),IQ_fft(2,i+1),IQ_fft(3,i+1),…,IQ_fft(N,i+1)}
{ IQ_fft(1,i+2),IQ_fft(2,i+2),IQ_fft(3,i+2),…,IQ_fft(N,i+2)}
……
{ IQ_fft(1,i+M-1),IQ_fft(2,i+M-1),IQ_fft(3,i+M-1),…,IQ_fft(N,i+M-1)}
Further, fast time-triggered protocol module 300 is also used to: according to preset threshold speed, the weight of initial transmissions signal
Multiple scanning frequency, the centre frequency of initial transmissions signal do quadrature demodulation to echo-signal to generate use during I/Q signal
Low-pass filter demodulation bandwidth, obtain the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value.
In an of the invention specific example, the corresponding frequency displacement cutoff frequency frej (i) of the pre-set velocity threshold value is indicated,
frej(i) = max( (i –1)/M*PRF*c/(2*abs(Vrej))-f0,-B_iq/2)
Wherein, PRF indicates the repetition scanning frequency of initial transmissions signal, and Vrej indicates pre-set velocity threshold value, and f0 is indicated just
Originate the centre frequency for penetrating signal, B_iq/2 indicate to do quadrature demodulation to echo-signal with generate use during I/Q signal it is low
Both the demodulation bandwidth of bandpass filter, abs () expression take absolute value, and max () expression takes the larger value.
Further, fast time-triggered protocol module 300 is also used to: according to the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value
Rate, which is obtained, makees the fast termporal filter being filtered to transform sequence before the filtering of M group on fast time orientation;
In one of which embodiment of the invention, on fast time orientation, fast time-triggered protocol module 300 is used to filter M group
Wavefront transform sequence does time-domain filtering processing.
Quadrature demodulation is done according to the corresponding frequency displacement cutoff frequency of the pre-set velocity threshold value and to echo-signal to generate
Numerical relation between the demodulation bandwidth of the low-pass filter used during I/Q signal, the design fast termporal filter are
Number.
If frej (i) is not equal to-B_iq/2,
Then the upper cut off frequency B_hp and lower limiting frequency B_lp of fast termporal filter are respectively as follows:
Bp_lp = -B_iq/2;
Bp_hp = frej(i);
If frej (i) is equal to-B_iq/2,
Then the coefficient of the fast termporal filter is 0.
Further, transform sequence is filtered by the fast time respectively before fast time-triggered protocol module 300 is used to filter M group
Wave device is filtered, to obtain M group filtering transformation sequence.
The M group filtering transformation sequence is successively are as follows:
{IQ_fft_filterd(1,i),IQ_fft_filterd(2,i),IQ_fft_filterd(3,i),…,IQ_
fft_filterd(N,i)}
{IQ_fft_filterd(1,i+1),IQ_fft_filterd(2,i+1),IQ_fft_filterd(3,i+
1),…,IQ_fft_filterd(N, i+1)}
{IQ_fft_filterd(1,i+2),IQ_fft_filterd(2,i+2),IQ_fft_filterd(3,i+
2),…,IQ_fft_filterd(N, i+2)}
……
{IQ_fft_filterd(1,i+M-1),IQ_fft_filterd(2,i+M-1),IQ_fft_filterd(3,i+
M-1),…,IQ_fft_filterd(N,i+M-1)}
In another embodiment of the present invention, on fast time orientation, fast time-triggered protocol module 300 is used to filter M group
Preceding transform sequence does frequency domain filtering processing.
Transform sequence does FFT transform and obtains FFT transform sequence before M group filters before filtering respectively to every group of M group;The M group
Filter preceding FFT transform sequence successively are as follows:
{IQ_fft_fast_fft(1,i),IQ_fft_fast_fft(2,i),IQ_fft_fast_fft(3,i),…,
IQ_fft_fast_fft(N,i)}
{IQ_fft_fast_fft(1,i+1),IQ_fft_fast_fft(2,i+1),IQ_fft_fast_fft(3,i+
1),…,IQ_fft_fast_fft(N, i+1)}
{IQ_fft_fast_fft(1,i+2),IQ_fft_fast_fft(2,i+2),IQ_fft_fast_fft(3,i+
2),…,IQ_fft_fast_fft(N, i+2)}
……
{IQ_fft_fast_fft(1,i+M-1),IQ_fft_fast_fft(2,i+M-1),IQ_fft_fast_fft(3,
i+M-1),…,IQ_fft_fast_fft(N,i+M-1)}
Fast time-triggered protocol module 300, which is also used to retain respectively, negative in FFT transform sequence before M group filters to be done echo-signal
Quadrature demodulation with generate the low-pass filter used during I/Q signal demodulation bandwidth and the pre-set velocity threshold value it is corresponding
Frequency component between frequency displacement cutoff frequency, and other components are set to 0;
FFT transform sequence does inverse FFT transformation before the filtering retained M group, to obtain multiple groups filtering transformation sequence.
The M group filtering transformation sequence is successively are as follows:
{IQ_fft_filterd(1,i),IQ_fft_filterd(2,i),IQ_fft_filterd(3,i),…,IQ_
fft_filterd(N,i)}
{IQ_fft_filterd(1,i+1),IQ_fft_filterd(2,i+1),IQ_fft_filterd(3,i+
1),…,IQ_fft_filterd(N, i+1)}
{IQ_fft_filterd(1,i+2),IQ_fft_filterd(2,i+2),IQ_fft_filterd(3,i+
2),…,IQ_fft_filterd(N, i+2)}
……
{IQ_fft_filterd(1,i+M-1),IQ_fft_filterd(2,i+M-1),IQ_fft_filterd(3,i+
M-1),…,IQ_fft_filterd(N,i+M-1)}
Further, in an embodiment of the present invention, output module 400 is used for: obtaining every group of filtering transformation sequence respectively
Corresponding complex-envelope obtains total envelope signal according to the corresponding complex-envelope of every group of filtering transformation sequence, for final
Frequency spectrum is shown.
In a specific embodiment of the invention, total envelope is obtained according to the corresponding complex-envelope of every group of filtering transformation sequence and is believed
During number, the average value, weighted average, minimum value, maximum of the corresponding complex-envelope of each group filtering transformation sequence can be removed
Value, boundary values and intermediate value are not described in detail herein as total envelope signal.
In following example, take the average value of the corresponding complex-envelope of each group filtering transformation sequence as total envelope signal.
Total envelope signal indicates with Spec_sum (i), then
Spec_sum(i)=fabs(IQ_fft_filterd(1,i))+fabs(IQ_fft_filterd(2,i))+…+
Fabs (IQ_fft_filterd (N, i)),
Wherein i=0,1,2 ... M, fabs () indicate the envelope for seeking every group of filtering transformation sequence plural number respectively.
Specifically, the dynamic compression module will obtain the system also includes dynamic compression module and display module
Total envelope signal carry out dynamic range compression, the display module be used for the data result Jing Guo dynamic compression resume module
Output display, is not described in detail herein.
It is apparent to those skilled in the art that for convenience and simplicity of description, the system of foregoing description
The specific work process of middle module, can be with reference to the corresponding process in preceding method embodiment, and details are not described herein.
In conclusion pulse Doppler wall filtering method of the invention and processing system, by I/Q signal in the slow time
Direction does Fast Fourier Transform (FFT) and obtains its frequency displacement distribution, to obtain for each frequency displacement and the corresponding signal frequency of cut-off speed
Component calculates the cutoff frequency on base band I/Q signal according to the frequency component, thus by carrying out this section in fast time orientation
The only filtering processing of frequency accurately filters out low speed clutter moition information, and pulse Doppler wall filtering processing method of the invention is not
The motion information lower than threshold speed scattering is only effectively eliminated, while effectively maintaining the scattering letter higher than threshold speed
Breath;The convenience and service efficiency for improving supersonic imaging apparatus, improve the quality of ultrasound image.
For convenience of description, it is divided into various modules when description apparatus above with function to describe respectively.Certainly, implementing this
The function of each module can be realized in the same or multiple software and or hardware when application.
As seen through the above description of the embodiments, those skilled in the art can be understood that the application can
It realizes by means of software and necessary general hardware platform.Based on this understanding, the technical solution essence of the application
On in other words the part that contributes to existing technology can be embodied in the form of software products, which can protect
In the presence of saving in medium, such as ROM/RAM, magnetic disk, CD, including some instructions are used so that computer equipment (can be with
It is personal computer, Information Push Server or the network equipment etc.) execute each embodiment of the application or embodiment
Certain parts described in method.
Device embodiments described above are only schematical, wherein the module as illustrated by the separation member
It may or may not be physically separated, the component shown as module may or may not be physics mould
Block, it can it is in one place, or may be distributed on multiple network modules.It can be selected according to the actual needs
In some or all of the modules realize the purpose of present embodiment scheme.Those of ordinary skill in the art are not paying creation
Property labour in the case where, it can understand and implement.
The application can describe in the general context of computer-executable instructions executed by a computer, such as program
Module.Generally, program module includes routines performing specific tasks or implementing specific abstract data types, programs, objects, group
Part, data structure etc..The application can also be practiced in a distributed computing environment, in these distributed computing environments, by
Task is executed by the connected remote processing devices of communication network.In a distributed computing environment, program module can be with
It is saved in medium positioned at the local and remote computer including saving equipment.
It should be appreciated that although this specification is described in terms of embodiments, but not each embodiment only includes one
A independent technical solution, this description of the specification is merely for the sake of clarity, and those skilled in the art should will say
As a whole, the technical solution in each embodiment may also be suitably combined to form those skilled in the art can for bright book
With the other embodiments of understanding.
The series of detailed descriptions listed above only for feasible embodiment of the invention specifically
Protection scope bright, that they are not intended to limit the invention, it is all without departing from equivalent implementations made by technical spirit of the present invention
Or change should all be included in the protection scope of the present invention.