CN102247168B - Method and device for processing multiple-beam point-by-point focusing delay parameters - Google Patents

Abstract

The embodiment of the invention discloses a method and device for processing multiple-beam point-by-point focusing delay parameters. The method has the following beneficial effects: computation of the focusing delay parameters of a plurality of scanning lines is converted to computation of the focusing delay parameters from centrosymmetric lines to equivalent virtual points by utilizing the symmetry of the scanning lines and the symmetry of the virtual points, thus greatly simplifying the computation complexity; and only the focusing delay parameters from the centrosymmetric lines to the special equivalent virtual points need to be stored, thus reducing the storage content of the parameters and avoiding the problem of sharp increases of the storage number and hardware complexity caused when the focusing delay parameters are stored in order to realize high-precision point-by-point focusing and the problem of great difficulty in engineering realization.

Description

A kind of multi-beam point-by-point focusing time delay parameters processing method and device

Technical field

The present invention relates to the ultrasonic technology field, particularly a kind of multi-beam point-by-point focusing time delay parameters processing method and device.

Background technology

Clinical medicine equipment requires the digital ultrasound image system can have the realtime imaging performance of high frame frequency mostly.But in traditional simple beam synthetic technology, the frame frequency of image is subject to the restriction of ultrasonic propagation velocity and investigation depth, often can't satisfy the requirement of numerous disease diagnosis.

Under the prerequisite that guarantees picture quality, the method that improves picture frame frequency adopts digital multi-beam synthetic technology often at present.This technology mainly is the emission-receive mode by particular design, utilizes primary emission to synthesize N root wave beam, and (theoretically) just can improve frame frequency N doubly.Because receive the employing of dynamic focusing, the lateral resolution of image has had significant raising.Yet in this process, the memory space that focuses on delay parameter also will significantly enlarge, and the most directly cause the increase of complexity and the hardware resource consumption of hardware system, so that multiple-beam point-by-point focusing has sizable technical difficulty.

In order to realize high-precision point-by-point focusing, must solve the problem that delay parameter generates in real time that focuses on.And address this problem the mode that main employing is stored focusing on delay parameter.But, because the memory space of parameter is very large, adopt this mode will cause the rapid increase of memorizer number and hardware complexity, in Project Realization, there is certain difficulty.

Summary of the invention

In view of this, the object of the present invention is to provide a kind of multi-beam point-by-point focusing time delay parameters processing method and device, specific embodiments is as follows:

A kind of multi-beam point-by-point focusing time delay parameters processing method comprises:

Determine the centre symmetry line of n bar scanning line;

Be minute virtual point such as described n bar scanning line arranges, each array element of probe is carried out the n five equilibrium, the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add to replenish virtual point, all virtual point are symmetrical along the center virtual point that is positioned at center array element;

Determine respectively the equivalent virtual point set that each bar scanning line is corresponding, equivalent virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equals respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line;

The equivalent virtual point set corresponding with described n bar scanning line determined in the equivalent virtual point set that comprehensive described each bar scanning line is corresponding;

Calculate described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line, and storage, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.

Preferably, the described process of determining that respectively equivalent virtual point corresponding to each bar scanning line gathered comprises:

Determine successively to be positioned at the equivalent virtual point set corresponding to scanning line of described centre symmetry line one side;

According to the centre symmetry of scanning line and the centre symmetry of virtual point, determine the equivalent virtual point set that described centre symmetry line opposite side scanning line is corresponding.

Preferably, the process of the delay parameter of each the equivalent virtual point of described computer center line of symmetry in equivalent virtual point set corresponding to described and described n bar scanning line comprises:

Calculate the relative time delay parameter between adjacent equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line;

Calculate the delay parameter of described centre symmetry line first equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line.

Preferably, the process of described computer center line of symmetry delay parameter of each equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line also comprises:

Difference according to the adjacent relative time delay time is determined quantization parameter;

Utilize described quantization parameter that the described relative time delay time is quantized to round.

Preferably, described storing process comprises:

Store the delay parameter of relative time delay time, quantization parameter and described centre symmetry line first the equivalent virtual point in the described equivalent virtual point set after described the rounding.

Preferably, the process of the delay parameter of corresponding each array element of each bar scanning line of described acquisition comprises:

Determine the corresponding equivalent virtual point set of each bar scanning line, and determine the equivalent virtual point in the corresponding equivalent virtual point set of each bar scanning line;

According to the delay parameter of the centre symmetry line of described storage each the equivalent virtual point in the equivalent virtual point set corresponding with described n bar scanning line, obtain the delay parameter of the equivalent virtual point of described centre symmetry line in the corresponding equivalent virtual point set of each bar scanning line.

A kind of device for processing multi-beam point-by-point focusing time delay parameters comprises:

Receive path is used for receiving n bar scanning line;

The processor that links to each other with described receive path, the centre symmetry line for determining n bar scanning line is minute virtual point such as described n bar scanning line arranges, and each array element of probe is carried out the n five equilibrium, the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add and replenish virtual point, all virtual point are symmetrical along the center virtual point that is positioned at center array element, determine respectively the equivalent virtual point set that each bar scanning line is corresponding, the equivalence virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equal respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line, the equivalent virtual point set corresponding with described n bar scanning line determined in the equivalent virtual point set that comprehensive described each bar scanning line is corresponding;

The computer that links to each other with described processor is used for calculating described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line;

The memorizer that links to each other with described computer, be used for storing described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.

Preferably, described computer comprises:

The relative time delay parameter calculating module is used for calculating the relative time delay parameter between the adjacent equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line;

The delay parameter computing module of the first equivalent virtual point is used for calculating described centre symmetry line to the delay parameter of equivalent first equivalent virtual point of virtual point set corresponding to described n bar scanning line.

Preferably, described computer also comprises:

The quantization parameter determination module is used for determining quantization parameter according to the difference of adjacent relative time delay time;

Round module, be used for utilizing described quantization parameter that the described relative time delay time is quantized to round.

Preferably, described memorizer also is used for storing relative time delay time, quantization parameter and described centre symmetry line after described the rounding to the delay parameter of described equivalent first equivalent virtual point of virtual point set.

The disclosed multi-beam point-by-point focusing time delay parameters processing method of the embodiment of the invention, utilize the symmetry of scanning line and the symmetry of virtual point, the calculating of the focusing delay parameter of multi-strip scanning line is converted to centre symmetry line calculates to the focusing delay parameter of equivalent virtual point, greatly simplified computation complexity, and, only need to preserve centre symmetry line to the focusing delay parameter of special equivalent virtual point, dwindled the memory space of parameter, avoided as realizing high-precision point-by-point focusing, when storing focusing on delay parameter, cause the rapid increase of memorizer number and hardware complexity, the large problem of difficulty in Project Realization.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, the below will do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art, apparently, accompanying drawing in the following describes only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain according to these accompanying drawings other accompanying drawing.

Fig. 1 is the flow chart of the disclosed a kind of multi-beam point-by-point focusing time delay parameters processing method of the embodiment of the invention;

Fig. 2 is that the flat battle array probe of disclosed 8 array elements of the embodiment of the invention focuses on schematic diagram;

Fig. 3 is that the flat battle array probe of 8 array elements focuses on equivalence conversion schematic diagram among Fig. 2;

Fig. 4 is the delay time function schematic diagram of i array element;

Fig. 5 is the relative time delay time function schematic diagram of i array element;

Fig. 6 is the flow chart of the delay parameter of each equivalent virtual point during the disclosed computer center of embodiment of the invention line of symmetry is gathered to described equivalent virtual point;

Fig. 7 is the structural representation of the disclosed device for processing multi-beam point-by-point focusing time delay parameters of the embodiment of the invention;

Fig. 8 is the structural representation of the disclosed computer of the embodiment of the invention.

The specific embodiment

Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that obtains under the creative work prerequisite.

The embodiment of the invention discloses a kind of multi-beam point-by-point focusing time delay parameters processing method, its idiographic flow comprises as shown in Figure 1:

Step S11, determine the centre symmetry line of n bar scanning line;

N be greater than integer, if current n is even number, the virtual scan line of centre symmetry line for determining according to current scanning line then, if current n is odd number, then centre symmetry line is the scanning line that is positioned at the centre position in the n bar scanning line.The scanning line of centre symmetry line both sides is symmetrical.Scanning line in the present embodiment is 4, and as shown in Figure 2,4 solid lines 1,2,3,4 are 4 scanning lines, and line of symmetry centered by the dotted line 0, array number are 8.

Step S12, for described n bar scanning line such as arranges at minute virtual point, each array element of popping one's head in is carried out the n five equilibrium, the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add to replenish virtual point, described virtual point is symmetrical along the center virtual point that is positioned at center array element;

Quantity according to scanning line is carried out five equilibrium with array element, and sets virtual point.Focus on shown in the schematic diagram such as the flat battle array probe of 8 array elements among Fig. 2, array element number is 8, and each array element is divided into quarter, and the distance between adjacent five equilibrium virtual point is d ₀, suppose array element distance D ₀Be 0.48mm, then virtual point spacing d ₀=D ₀/ 4=0.12mm needs 33 five equilibrium virtual point altogether, and then distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add to replenish virtual point, then have 35 virtual point.These 35 virtual point are along the 18th virtual point left-right symmetric.

Step S13, respectively equivalent virtual point set corresponding to definite each bar scanning line, equivalent virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equals respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line;

As shown in Figure 2, the M point is any point on No. 0 line, the P point be on the Line 1 a bit, Q point be on No. 2 lines a bit, M point, P point and Q point are equal to the vertical dimension of array element.As seen from Figure 2, P, the Q o'clock focusing delay time to 1～No. 8 array element is:

$\left\{\begin{array}{c}{\mathrm{\τ}}_P=\{{\mathrm{\τ}}_{P,4},{\mathrm{\τ}}_{P,8},...,{\mathrm{\τ}}_{P,32}\}\\ {\mathrm{\τ}}_Q=\{{\mathrm{\τ}}_{Q,4},{\mathrm{\τ}}_{Q,8},...,{\mathrm{\τ}}_{Q,32}\}\end{array}\right.$ Formula (1)

P o'clock distance to 1 array element (be P o'clock to the distance of No. 4 virtual point) equals at M o'clock to the distance of No. 7 virtual point; P o'clock distance to 2 array elements (be P o'clock to the distance of No. 8 virtual point) equals at M o'clock to the distance of No. 11 virtual point; P o'clock distance to 8 array elements (be P o'clock to the distance of No. 32 virtual point) equals at M o'clock to the distance of No. 35 virtual point.So the distance to 8 array elements equaled respectively at M o'clock to the distance of 7,11,15,19,23,27,31 and No. 35 virtual point, namely in P o'clock

τ _P=τ _M={ τ _{M, 7}, τ _{M, 11}..., τ _{M, 35}Formula (2)

Can draw thus, No. 1 equivalent virtual point set corresponding to scanning line is (7,11,15,19,23,27,31,35)

In like manner, the Q o'clock distance to 8 array elements equals respectively at M o'clock to the distance of 5,9,13,17,21,25,29 and No. 33 virtual point, namely on No. 2 scanning lines

τ _Q=τ _M={ τ _{M, 5}, τ _{M, 9}..., τ _{M, 33}Formula (3)

No. 2 equivalent virtual point set corresponding to scanning line are (5,9,13,17,21,25,29,33).

In the present embodiment, can determine successively the equivalent virtual point set of No. 3 and No. 4 scanning line in the manner described above, also can in the following manner, determine the equivalent virtual point set of No. 3 and No. 4 scanning line simultaneously.

Since No. 3 and No. 4 scanning line along centre symmetry line respectively with No. 2 and No. 1 scanning line symmetry, and virtual point is equally along the 18th virtual point symmetry, therefore can infer the equivalent virtual point set symmetry that the equivalent virtual point in the equivalent virtual point set of No. 3 scanning line is corresponding with No. 2 scanning line.Because the set of the equivalent virtual point of No. 2 scanning line for (5,9,13,17,21,25,29,33) then, No. 3 equivalent virtual point set corresponding to scanning line is (31,27,23,19,15,11,7,3), from left to right sorting in position according to the array element at each equivalent virtual point place, then can obtain No. 3 equivalent virtual point set (3,7,11,15,19,23,27,31) corresponding to scanning line

Said process is summarized, then is:

Determine successively to be positioned at the equivalent virtual point corresponding to scanning line of described centre symmetry line one side;

According to the centre symmetry of described scanning line and the centre symmetry of virtual point, determine equivalent virtual point corresponding to described centre symmetry line opposite side scanning line.

The equivalent virtual point set corresponding with described n bar scanning line determined in step S14, the equivalent virtual point set that comprehensive described each bar scanning line is corresponding;

Can find through said process, the equivalent virtual point that coincidence is arranged in the equivalent virtual point set of above-mentioned 2 scanning lines, therefore, after it is gathered, find, if need to obtain the focusing delay parameter of the 1st, No. 2 scanning line, only need to calculate the M o'clock delay parameter to 5,7,9,11,13,15,17,19,23,25,27,29,31,33 and No. 35 virtual point.

And according to the symmetry of scanning line in the above-mentioned steps and the symmetry of virtual point, the focusing delay parameter of the 3rd, No. 4 scanning line can obtain from the above-mentioned delay parameter that calculates.For example, the delay parameter of No. 3 scanning line No. 3 virtual point of line of symmetry to the centered by the focusing delay parameter of first array element, therefore and No. 3 virtual point and No. 33 virtual point symmetry, the focusing delay parameter of No. 3 scanning line No. 33 virtual point of line of symmetry to the centered by the focusing delay parameter of first array element.

Can determine that 4 equivalent virtual point set corresponding to scanning line are (5,7,9,11,13,15,17,19,23,25,27,29,31,33 and 35) this moment.

Further, in the present embodiment, can utilize equally the symmetry of virtual point, the the 5th, 7,9,11,13,15,17,19,23,25,27,29,31,33 and No. 35 virtual point in the above-mentioned equivalent virtual point set all is converted to the virtual point that is positioned at No. 18 virtual point left side or right side, for example, No. 35 virtual point and No. 1 virtual point symmetry, then the M o'clock delay parameter to No. 35 virtual point equals at M o'clock to the delay parameter of No. 1 virtual point.According to said process, can find out, with No. 19 virtual point-symmetric be No. 17 virtual point, with No. 23 virtual point-symmetric be No. 13 virtual point, corresponding with No. 25 virtual point is the o.11 virtual point, corresponding with No. 27 virtual point is No. 9 virtual point, corresponding with No. 29 virtual point is No. 7 virtual point, corresponding with No. 31 virtual point is No. 5 virtual point, and corresponding with No. 33 virtual point be No. 3 virtual point, to sum up, can be with M o'clock to the 5th, 7,9,11,13,15,17,19,23,25,27,29,31, the focusing delay parameter equivalence of 33 and No. 35 virtual point is that M o'clock to the 1st, 3,5,7,9,11,13, the delay parameter of 15 and No. 17 points.At this moment, can determine that 4 equivalent virtual point set corresponding to scanning line are (1,3,5,7,9,11,13,15 and 17)

The delay parameter of each the described equivalent virtual point in step S15, the described centre symmetry line of calculating are gathered to the equivalent virtual point corresponding with described n bar scanning line, and storage, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.。

We can draw 4 equivalent virtual point set that scanning line is corresponding according to above analysis.In this step, distinguish the delay parameter of each equivalent virtual point in equivalent virtual point set corresponding to computer center's line of symmetry to 4 scanning line, and result of calculation is stored.

The focusing delay parameter of storage is used in the point-by-point focusing process, obtains the delay parameter of corresponding each array element of each bar scanning line.Concrete process can comprise:

Determine described scanning line to the corresponding equivalent virtual point set of the distance of each array element, and determine the equivalent virtual point in the described equivalent virtual point set;

According to the centre symmetry line of the described storage delay parameter to each described equivalent virtual point, obtain the delay parameter of the equivalent virtual point of described centre symmetry line in the described equivalent virtual point set.

Take No. 2 scanning line as example, its equivalent virtual point set is (5,9,13,17,21,25,29,33), then from the line of symmetry of above-mentioned calculating storage to the delay parameter of each equivalent virtual point, obtain the focusing delay parameter of each equivalent virtual point in its set.

Can realize through said process, the computational process of multi-beam point-by-point focusing time delay parameters is converted to centre symmetry line to the calculating of the focusing delay parameter of virtual point.And the result that will calculate stores, so that the follow-up result that can utilize storage according to above-mentioned symmetry characteristic, obtains the focusing delay parameter of corresponding each array element of each bar scanning line.

Fig. 3 is that the flat battle array probe of 8 array elements focuses on equivalence conversion schematic diagram, d=D among Fig. 2 ₀/ 2=0.24mm, and N point M point in the distance at array element center and Fig. 2 equates to the distance at array element center among Fig. 3, thus among Fig. 21,3,5,7,9,11,13,15 and 17 distances that 1～9 array element is ordered to N in the distance of M and Fig. 3 equate respectively namely have

τ _{M, 2i-1}=τ _{N, i}I=1,2 ..., 9 formula (4)

So the calculating that four wave beams among Fig. 2 is focused on delay parameter can be converted to the calculating that simple beam among Fig. 3 is focused on delay parameter.

If F is focal length (distance from the submatrix center to focus N), investigation depth L is 240mm, and the average speed c of ultrasound wave in human body soft tissue is 1540m/s, and the distance between the adjacent array element is 1/2 of former array element distance, d=0.24mm, can draw between i array element and the focusing center's line apart from a _iFor

$a_i=|\frac{18+1}{2}-i|\×d,(i=\mathrm{1,2},\·\·\·,18)$ Formula (5)

Can be got by (5)

0.12mm≤a _i≤2.04mm

According to Pythagorean theorem, can calculate the delay time of i array element

${\mathrm{\&tau;}}_i(F,a_i)=(\sqrt{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}-F)/c$ Formula (6)

If AD converter speed f _sBe 50MHz, realize that point-by-point focusing requires each the echo point on the beam axis is focused on, so the interval delta F of focus point be on the focal line

Δ F=c/2f _s=0.0154mm formula (7)

Adopt the centrosymmetry receive mode of 18 array elements, can calculate the point-by-point focusing time delay of 18 array elements according to formula (5)～(7), consider to receive array element left and right sides centrosymmetry, only list the depth of focus as shown in table 1 from 1～9 array element point-by-point focusing delay parameters between 2mm～240mm.

The point-by-point focusing delay parameters of table 1 1～9 array element (unit of time: 1.0 nanoseconds)

Can find by said process, utilize the symmetry of scanning line and the symmetry of virtual point, the disclosed multi-beam point-by-point focusing time delay parameters processing method of the present embodiment is converted to centre symmetry line to the focusing delay parameter calculating of equivalent virtual point with the calculating of the focusing delay parameter of multi-strip scanning line, greatly simplified computation complexity, and, only need to preserve centre symmetry line to the focusing delay parameter of special equivalent virtual point, dwindled the memory space of parameter, avoided as realizing high-precision point-by-point focusing, when storing focusing on delay parameter, cause the rapid increase of memorizer number and hardware complexity, the large problem of difficulty in Project Realization.

In above-described embodiment, although the processing procedure of multi-beam point-by-point focusing time delay parameters is converted to the point-by-point focusing delay parameters computational process of simple beam, its memory space is dwindled greatly, but, if his-and-hers watches 1 data round rear direct storage, needing to adopt 9 16 storage depth is the data storage of 16K, if add the interpolation circuit of each array element of point-by-point focusing module, and relevant peripheral control circuit, so will be so that the demand of hardware resource to be very huge, also there is certain difficulty in this in Project Realization.

After formula (6) carried out differentiate, can obtain:

$\left\{\begin{array}{c}\frac{d{\mathrm{\&tau;}}_i(F,a_i)}{\mathrm{dF}}=[\frac{F}{\sqrt{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}}-1]/c\&le;0\\ \frac{{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">d</figure-callout>}}^2{\mathrm{\&tau;}}_i(F,a_i)}{\mathrm{<figure-callout\; id="2"\; label="d\; F\; i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">d</figure-callout>}{F_i}^{}{{}_{}}^2}=\left[\frac{\sqrt{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}-\frac{F^2}{\sqrt{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}}}{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}\right]/c\&GreaterEqual;0\\ \frac{d{\mathrm{\&tau;}}_i(F,a_i)}{d{a}_i}=\left[\frac{a_i}{\sqrt{{a_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}}^2+F^2}}\right]/c\&GreaterEqual;0\end{array}\right.$ Formula (8)

According to formula (8) as can be known, τ _i(F, a _i) be the monotone decreasing concave function of F, its decline rate is slack-off gradually.τ _i(F, a _i) be a _iMonotonically increasing function, so be the monotonic decreasing function of i, τ _i(F, a _i) function as shown in Figure 4.

Can find in conjunction with Fig. 3 and table 1: the delay time τ of each array element point-by-point focusing _i(F, a _i) along with the increase of depth of focus F reduces gradually, τ _i(F, a _i) also corresponding the reducing of graded of function, the delay time pace of change also slows down gradually.Near the 9th array element of focal line, focus on delay time τ ₉(F, a ₉) variation is little, variation is slow, and is less to storage capacity requirement; And away from the 1st array element of focal line, focus on delay time τ ₁(F, a ₁) the change in value scope large, pace of change is fast, this is to cause the basic reason large to storage capacity requirement.

Therefore in order to realize focusing on the compression storage of delay parameter, must dwindle the data variation scope that focuses on delay time, reduce to focus on the speed that delay parameter changes.According to formula (6), can calculate the delay time Δ τ between the adjacent array element _i(F, a _i).

$\left\{\begin{array}{c}\mathrm{\&Delta;}{\mathrm{\&tau;}}_i(F,a_i)={\mathrm{\&tau;}}_i(F,a_i)-{\mathrm{\&tau;}}_{i+1}(F,a_i)\\ (i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,8)\\ \mathrm{\&Delta;}{\mathrm{\&tau;}}_9(F,a_9)={\mathrm{\&tau;}}_9(F,a_9)\end{array}\right.$ Formula (9)

Δ τ _i(F, a _i) remain the monotone decreasing function of F and i, along with the increase of F and i, Δ τ _i(F, a _i) reduce i array element relative time delay time Δ τ in 1～9 array element _i(F, a _i) function as shown in Figure 5.

According to the difference on any both sides of the triangle principle less than the 3rd limit, Δ τ in the formula (9) _i(F, a _i) span satisfy following constraints:

$0<\mathrm{\&Delta;}{\mathrm{\&tau;}}_i(F,{\mathrm{\&beta;}}_i)<\frac{d}{c}$ Formula (10)

As long as so determined the focusing delay time τ of i array element _i(F, a _i), the focusing delay time of adjacent i-1 array element can be obtained according to formula (9) recursion.Because Δ τ _i(F, a _i) satisfy constraint equation (10), under the quantum condition of equal accuracy, to Δ τ _i(F, a _i) storage compare τ _i(F, a _i) relatively easy, memory space is also less.

According to above analysis, τ _iBe the focusing delay time of i array element, Δ τ _iBe i array element with respect to the focusing relative time delay time of i+1 array element, Δ τ then _iWith τ _iThere is following relation:

τ ₉=Δτ ₉

τ ₈=Δτ ₈+τ ₉

………

τ ₂=Δτ ₂+τ ₃

τ ₁=Δ τ ₁+ τ ₂Formula (11)

Therefore, further, the process of the delay parameter of each equivalent virtual point comprised as shown in Figure 6 during computer center's line of symmetry was gathered to described equivalent virtual point:

Relative time delay parameter during step S61, the equivalent virtual point that the described n bar scanning line of calculating is corresponding are gathered between adjacent equivalent virtual point;

It is as shown in table 2,

The point-by-point focusing relative time delay parameter (unit of time: 1.0 nanoseconds) of table 21～9 array elements

The focusing delay parameter of first equivalent virtual point during step S62, the described centre symmetry line of calculating are gathered to equivalent virtual point corresponding to described n bar scanning line.

According to above-mentioned steps, calculate the focusing delay parameter of first the equivalent virtual point in equivalent virtual point set corresponding to n bar scanning line, and the relative time delay parameter between adjacent equivalent virtual point, then can according to the relative time delay parameter, obtain the focusing delay parameter of each equivalent virtual point.Further dwindled memory data output.

Further, the data of table 2 with table 1 are compared, can find: between 2～240mm, the point-by-point focusing relative time delay parameter of 1～9 array element has following characteristics:

(1) initial value of the initial value of each array element delay data data in the table 1 in the table 2, the change in value scope in the table 2 obviously reduces, and decline rate obviously slows down.

(2) according to the data in the table 2, application formula (11) can be calculated generation table 1 data in real time.

So, can realize focusing on the compression storage of delay parameter according to the feature (1) of table 2 data, can finish the real-time calculating of compression parameters according to the feature (2) of table 2.

By said process, can realize, only need the focusing delay parameter of first equivalent virtual point of storage and the relative time delay parameter between adjacent equivalent virtual point, thereby further dwindled memory data output, reduced the difficulty of Project Realization.

Further, the process of described computer center line of symmetry delay parameter of each equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line can also comprise:

The difference of step S63, adjacent relative time delay time of foundation is determined quantization parameter;

Step S64, utilize described quantization parameter that the described relative time delay time is quantized to round.

Accordingly, described storing process comprises: the delay parameter of storing relative time delay time, quantization parameter and described centre symmetry line first the equivalent virtual point in the described equivalent virtual point set after described the rounding.

The below is elaborated to said process:

When focal length F from 2mm to the 240mm change procedure, Δ τ _i(F, a _i) progressively reduce, when focal length changes to F+ Δ F from F, Δ τ _i(F, a _i) variable quantity be designated as Δ γ.

Δ γ=Δ τ _i(F, a _i)-Δ τ _i((F+ Δ F), a _i) formula (12)

When F from 2mm to the 240mm change procedure, make Δ τ _i(F, a _i) maximum variable quantity be designated as Δ γ _Max

$\left\{\begin{array}{cc}\mathrm{\&Delta;}{\mathrm{\&gamma;}}_{\max }=\max [\mathrm{\&Delta;}{\mathrm{\&tau;}}_i(F,a_i)-\mathrm{\&Delta;}{\mathrm{\&tau;}}_i((F+\mathrm{\&Delta;F}),a_i)]& \\ F\&Element;\left[\mathrm{2,240}\right]& 1\&le;i\&le;8\end{array}\right.$ Formula (13)

Following formula is found the solution and can be got, Δ γ _Max=0.4593ns, the needs of incorporation engineering reality, in order to realize high-precision point-by-point focusing, the focusing time-delay quantizing factor of establishing each array element is γ, to Δ τ _i(F, a _i) value that rounds after the quantification is designated as Δ T _i(F, a _i).

$\left\{\begin{array}{c}\mathrm{\&Delta;}{T}_i(F,a_i)=\left[\frac{\mathrm{\&Delta;}{\mathrm{\&tau;}}_i(F,a_i)+\mathrm{\&gamma;}/2}{\mathrm{\&gamma;}}\right]\\ (i=\mathrm{1,2},\&CenterDot;\&CenterDot;\&CenterDot;,9)\end{array}\right.$ Formula (14)

Quantize to round according to formula (14) his-and-hers watches 2 data, the focusing relative time delay data of each array element all are quantified as integer.When satisfying Δ γ _MaxDuring＜γ constraints, can draw relational expression (15).

$\frac{\mathrm{\&Delta;\&gamma;}}{\mathrm{\&gamma;}}=\frac{\mathrm{\&Delta;}{\mathrm{\&tau;}}_i(F,a_i)-\mathrm{\&Delta;}{\mathrm{\&tau;}}_i((F+\mathrm{\&Delta;F}),a_i)}{\mathrm{\&gamma;}}<1$ Formula (15)

Can derive formula (16) according to formula (14), (15).

Formula (16)

As long as so use greater than Δ γ _MaxFocusing time-delay quantize data Δ τ in the factor gamma his-and-hers watches 2 _i(F, a _i) quantize to round and obtain Δ T _i(F, a _i), can guarantee when focus point F from 2mm to the 240mm change procedure, Δ T _i(F, a _i) variation littlely equal 1.

Make γ=2.5ns〉Δ γ _Max, according to formula (14), after the delay parameter in the his-and-hers watches 2 quantizes to round processing, can obtain table 3:

The point-by-point focusing relative time delay parameter (unit of time: 2.5ns) of 1～9 array element after table 3 quantizes to round

As can be seen from the above-described embodiment, the quantizing factor γ in the present embodiment is sampling interval T _s1/8(2.5ns/20ns), can become simple shifter-adder computing (please replenish the principle of this process implementation) so that linear interpolation is calculated like this.It is sampling interval T that the present embodiment does not limit the quantification factor gamma _s1/8, it also can be sampling interval T usually _s1/4, i.e. 5ns or 1/2, i.e. 10ns is like this so that interpolation calculation is easier.Obviously, the quantizing factor γ that focuses on delay parameter is larger, Δ T _i(F, a _i) initial value less, Δ T _i(F, a _i) saltus step is slower, and Δ T _i(F, a _i) change in value less than or equal to 1, therefore, table 1 data Δ T _i(F, a _i) memory space lower.

As can be seen from Table 3, the memory space of each array element delay data is very little, because Δ T _iThere is the restriction relation of formula (16) to set up, the Δ T after each array element quantizes to round _iThere is a large amount of repetitions, the relative time delay parameter Δ T of each array element _iWhen exist changing, also be to successively decrease by 1, and along with the increase of the depth of focus, Δ T _iRate of change reduce gradually, thereby so that the quantitative change of table 3 data storage is little, easily storage.

According to formula (11), can obtain similarly about T _iWith Δ T _iRecurrence Relation (17)

T ₉=ΔT ₉

T ₈=ΔT ₈+T ₉

Formula (17)

T ₂=ΔT ₂+T ₃

T ₁=ΔT ₁+T ₂

So, in engineering reality, only need storage list 3 first row data Δ T _iInitial value, and record 1～9 array element relative time delay data Δ T _iThe data storage of his-and-hers watches 3 can be finished in the position that changes.In the process of point-by-point focusing, according to the position that each array element relative time delay data change, revise in real time the relative time delay data Δ T after each array element quantizes _i, again according to formula (17), can calculate in real time the delay and focusing parameter T of 1～9 array element _i, guaranteed under the prerequisite than the small data memory space, realize the point-by-point focusing process.

In the disclosed multi-beam point-by-point focusing time delay parameters processing method of the present embodiment, because storage is relative time delay parameter after quantizing to round, compare with direct storage relative time delay parameter and can have certain error, but because its error is very little, therefore, can't the precision of whole processing procedure be impacted.For example, suppose τ _P, τ _QTwo relative time delay parameters before quantizing, T _P, T _QBe the relative time delay parameter after quantizing to round, can be obtained by flow process shown in Figure 1 and Fig. 2,

$\left\{\begin{array}{c}{T}_P={\{T_{P,4},T_{P,8},...,T_{P,3}\}}_2=\{T_4,{\mathrm{<figure-callout\; id="6"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_6,{\mathrm{<figure-callout\; id="8"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_8,{\mathrm{<figure-callout\; id="9"\; label="T"\; filenames="HDA0000081825770000031.png"\; state="\{\{state\}\}">T</figure-callout>}}_9,{\mathrm{<figure-callout\; id="7"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_7,T_5,{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_3,T_1\}\\ T_Q={\{T_{Q,4},T_{Q,8},...,T_{Q,3}\}}_2=\{{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_3,T_5,{\mathrm{<figure-callout\; id="7"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_7,{\mathrm{<figure-callout\; id="9"\; label="T"\; filenames="HDA0000081825770000031.png"\; state="\{\{state\}\}">T</figure-callout>}}_9,{\mathrm{<figure-callout\; id="8"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_8,{\mathrm{<figure-callout\; id="6"\; label="T"\; filenames="HDA0000081825770000021.png"\; state="\{\{state\}\}">T</figure-callout>}}_6,T_4,T_2\}\end{array}\right.$ Formula (18)

Make relative error Δ ε _i=Δ τ _i(F, a _i)-γ Δ T _i(F, a _i), according to formula (11), (17), can calculate and obtain T _iWith τ _iError ε _i

${\mathrm{\&epsiv;}}_i={\mathrm{\&tau;}}_i(F,a_i)-\mathrm{\&gamma;}{T}_i(F,a_i)=\underset{k=\mathrm{<figure-callout\; id="9"\; label="i"\; filenames="HDA0000081825770000031.png"\; state="\{\{state\}\}">i</figure-callout>}}{\overset{9}{\mathrm{\&Sigma;}}}\mathrm{\&Delta;}{\mathrm{\&epsiv;}}_k$ Formula (19)

Find the solution and to get error ε by carrying out numerical computations _iMaximum deviation less than 5.63ns, meet the requirement of high accuracy point-by-point focusing fully.According to formula (19) as can be known, ε _iγ is inversely proportional to quantizing factor, and γ is larger, and focusing accuracy is lower.

Can find out in sum, the disclosed multi-beam point-by-point focusing time delay parameters processing method of the embodiment of the invention has the following advantages at least:

1, memory space is dwindled greatly, is easy to realize.When the depth of focus during from 2mm to 240mm, according to formula (7) as can be known, focal point interval is 0.0154mm, if directly four wave beam focus data are rounded storage, the storage of each delay data needs 2 bytes, and its total storage capacity is:

M=15455×8×2×2=494560bytes

And adopt the disclosed multi-beam point-by-point focusing time delay parameters processing method of the embodiment of the invention, only need the initial value Δ T of 1～9 array element in the storage list 3 _i(2mm, a _i) (i=1 ..., 9) and this numerical value of storage Δ T in during focusing _i1 particular location successively decreases.The storage of each initial value needs 1 byte, its memory space M ₁For:

M ₁=(18/2)×1=9bytes

Each Δ T _i(F, a _i) 1 the particular location of successively decreasing needs 2 bytes store, its memory data output is first row initial value Δ T in the table 1 _i(2mm, a _i) sum deducts last row value Δ T _i(240mm, a _i) sum, memory space M ₂For:

${\mathrm{<figure-callout\; id="2"\; label="M"\; filenames="HDA0000081825770000021.png,HDA0000081825770000031.png"\; state="\{\{state\}\}">M</figure-callout>}}_2=\left[\underset{i=1}{\overset{9}{\mathrm{\&Sigma;}}}(\mathrm{\&Delta;}{T}_i(2\mathrm{mm},a_i)-\mathrm{\&Delta;}{T}_i(240\mathrm{mm},a_i))\right]*2$

$=(222-0)*2=444\mathrm{bytes}$

So the compression memory space of table 3 is M ₁+ M ₂=231bytes, memory capacity only is 1/2141 of table 1, therefore, can directly utilize the memorizer of FPGA inside to realize.

2, precision is high, and error is little, can satisfy the demand of the requirement of high accuracy point-by-point focusing.

Further, in the multi-beam point-by-point focusing time delay parameters processing method disclosed by the invention, can also adopt the dynamic aperture technology, further significantly reduce the delay time away from the reception array element of centre symmetry line, thereby so that dual port RAM memory capacity decrease, the memory data output of table 3 also can significantly reduce simultaneously.

Simultaneously, the invention discloses the device for processing multi-beam point-by-point focusing time delay parameters of using said method, its structure comprises as shown in Figure 7: receive path 71, processor 72, computer 73 and memorizer 74.

Receive path 71 is used for receiving n bar scanning line;

The processor 72 that links to each other with described receive path is used for determining the centre symmetry line of n bar scanning line, is minute virtual point such as described n bar scanning line arranges, and each array element of probe is carried out the n five equilibrium, and the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add and replenish virtual point, described virtual point is symmetrical along the center virtual point that is positioned at center array element, determine respectively the equivalent virtual point set that each bar scanning line is corresponding, equivalent virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equal respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line, comprehensive determining unit, be used for equivalent virtual point set corresponding to comprehensive described each bar scanning line, determine the equivalent virtual point set corresponding with described n bar scanning line;

The computer 73 that links to each other with described processor be used for calculating described centre symmetry line to equivalent virtual point set corresponding to described n bar scanning line in the delay parameter of each described equivalent virtual point;

The memorizer 74 that links to each other with described computer be used for storing described centre symmetry line to equivalent virtual point set corresponding to described n bar scanning line in the delay parameter of each described equivalent virtual point, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.

Further, disclosed computer 73 structures of the present embodiment comprise as shown in Figure 8: relative time delay parameter calculating module 731 is used for calculating the relative time delay parameter between the adjacent equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line; The delay parameter computing module 732 of the first equivalent virtual point is used for calculating described centre symmetry line to the delay parameter of equivalent first equivalent virtual point of virtual point set corresponding to described n bar scanning line.

Also comprise:

Quantization parameter determination module 733 is used for determining quantization parameter according to the difference of adjacent relative time delay time;

Round module 734, be used for utilizing described quantization parameter that the described relative time delay time is quantized to round.

Further, described memorizer 74 also is used for storing relative time delay time, quantization parameter and described centre symmetry line after described the rounding to the delay parameter of described equivalent first equivalent virtual point of virtual point set.

The work process of each device and module can be with reference to the step among the said method embodiment in the disclosed device of the present embodiment, and particular content repeats no more.Memorizer in the present embodiment can be dual port RAM, i.e. shared multiport memory allows two independently CPU or controller storage unit access asynchronously simultaneously, is more applicable for data buffer storage real-time in the present embodiment.

To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the present invention.Multiple modification to these embodiment will be apparent concerning those skilled in the art, and General Principle as defined herein can be in the situation that do not break away from the spirit or scope of the present invention, in other embodiments realization.Therefore, the present invention will can not be restricted to these embodiment shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims (10)

1. a multi-beam point-by-point focusing time delay parameters processing method is characterized in that, comprising:

Determine the centre symmetry line of n bar scanning line;

Be minute virtual point such as described n bar scanning line arranges, each array element of probe is carried out the n five equilibrium, the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add to replenish virtual point, all virtual point are symmetrical along the center virtual point that is positioned at center array element;

Determine respectively the equivalent virtual point set that each bar scanning line is corresponding, the equivalence virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equals respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line;

The equivalent virtual point set corresponding with described n bar scanning line determined in the equivalent virtual point set that comprehensive described each bar scanning line is corresponding;

Calculate described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line, and storage, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.

2. method according to claim 1 is characterized in that, the described process of determining that respectively equivalent virtual point corresponding to each bar scanning line gathered comprises:

Determine successively to be positioned at the equivalent virtual point set corresponding to scanning line of described centre symmetry line one side;

According to the centre symmetry of scanning line and the centre symmetry of virtual point, determine the equivalent virtual point set that described centre symmetry line opposite side scanning line is corresponding.

3. method according to claim 2 is characterized in that, described computer center line of symmetry comprises to the process of the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described and described n bar scanning line:

Calculate the relative time delay parameter between adjacent equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line;

Calculate the delay parameter of described centre symmetry line first equivalent virtual point in equivalent virtual point set corresponding to described n bar scanning line.

4. method according to claim 3 is characterized in that, the process of the delay parameter of each equivalent virtual point also comprised during described computer center line of symmetry was gathered to equivalent virtual point corresponding to described n bar scanning line:

Difference according to the adjacent relative time delay time is determined quantization parameter;

Utilize described quantization parameter that the described relative time delay time is quantized to round.

5. method according to claim 4 is characterized in that, described storing process comprises:

Store the delay parameter of relative time delay time, quantization parameter and described centre symmetry line first the equivalent virtual point in the described equivalent virtual point set after described the rounding.

6. the described method of any one is characterized in that according to claim 1-5, and the process of the delay parameter of corresponding each array element of each bar scanning line of described acquisition comprises:

Determine the corresponding equivalent virtual point set of each bar scanning line, and determine the equivalent virtual point in the corresponding equivalent virtual point set of each bar scanning line;

According to the delay parameter of the centre symmetry line of described storage each the equivalent virtual point in the equivalent virtual point set corresponding with described n bar scanning line, obtain the delay parameter of the equivalent virtual point of described centre symmetry line in the corresponding equivalent virtual point set of each bar scanning line.

7. a device for processing multi-beam point-by-point focusing time delay parameters is characterized in that, comprising:

Receive path is used for receiving n bar scanning line;

The processor that links to each other with described receive path, the centre symmetry line for determining n bar scanning line is minute virtual point such as described n bar scanning line arranges, and each array element of probe is carried out the n five equilibrium, the distance between adjacent five equilibrium virtual point is d ₀, and distance is d before first five equilibrium virtual point and after last five equilibrium virtual point ₀The position, add and replenish virtual point, all virtual point are symmetrical along the center virtual point that is positioned at center array element, determine respectively the equivalent virtual point set that each bar scanning line is corresponding, the equivalence virtual point is, equal this scanning line to the virtual point of the distance of certain array element with the distance of centre symmetry line, described equivalent virtual point set is, equal respectively this scanning line to the set of the equivalent virtual point of the distance of each array element with the distance of centre symmetry line, the equivalent virtual point set corresponding with described n bar scanning line determined in the equivalent virtual point set that comprehensive described each bar scanning line is corresponding;

The computer that links to each other with described processor is used for calculating described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line;

The memorizer that links to each other with described computer, be used for storing described centre symmetry line to the delay parameter of each interior described equivalent virtual point of the equivalent virtual point set corresponding with described n bar scanning line, the centre symmetry line of described storage is used for to the delay parameter of each interior equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line, obtains the delay parameter of corresponding each array element of each bar scanning line.

8. device according to claim 7 is characterized in that, described computer comprises:

The relative time delay parameter calculating module is used for calculating the relative time delay parameter between the adjacent equivalent virtual point of equivalent virtual point set corresponding to described n bar scanning line;

The delay parameter computing module of the first equivalent virtual point is used for calculating described centre symmetry line to the delay parameter of equivalent first equivalent virtual point of virtual point set corresponding to described n bar scanning line.

9. device according to claim 8 is characterized in that, described computer also comprises:

The quantization parameter determination module is used for determining quantization parameter according to the difference of adjacent relative time delay time;

Round module, be used for utilizing described quantization parameter that the described relative time delay time is quantized to round.

10. device according to claim 9, it is characterized in that, described memorizer also is used for storing relative time delay time, quantization parameter and described centre symmetry line after described the rounding to the delay parameter of described equivalent first equivalent virtual point of virtual point set.

Images