CN108182329A - A kind of radio frequency coil designs method and loop construction using particle cluster algorithm - Google Patents
A kind of radio frequency coil designs method and loop construction using particle cluster algorithm Download PDFInfo
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- CN108182329A CN108182329A CN201810012102.3A CN201810012102A CN108182329A CN 108182329 A CN108182329 A CN 108182329A CN 201810012102 A CN201810012102 A CN 201810012102A CN 108182329 A CN108182329 A CN 108182329A
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/32—Excitation or detection systems, e.g. using radio frequency signals
- G01R33/34—Constructional details, e.g. resonators, specially adapted to MR
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Abstract
The invention belongs to mr imaging technique fields, it is related to a kind of radio frequency coil designs method and loop construction using particle cluster algorithm, it is mainly used in the magnetic resonance imaging to human body brain, radio-frequency coil wiring area is selected on a hemisphere face, its internal hemi-spherical cavities formed for wrapping up brain, coil below forms magnetic field component units, set up the major part of RF magnetic field, coil above it is used to compensate magnetic field so that the magnetic field in the specific region inside hemi-spherical cavities tends to be uniform；By the height where the number N and coil of regulating winding come the performance of regulating winding, search for optimal loop construction on a large scale by particle cluster algorithm, it is designed by algorithm instead of traditional blindness test of many times, design efficiency, the fussy degree for alleviating design are improved, improves the designing quality of loop construction.
Description
Technical field
The invention belongs to mr imaging technique fields, are related to a kind of radio frequency coil designs method using particle cluster algorithm
And loop construction.
Background technology
Mr imaging technique is used in area of medical diagnostics extensive use, high-field magnetic resonance medical image system due to it
The limitation of condition can not be provided in general section office, and the MR imaging apparatus of low field permanent-magnet structure is with respect to the ultralow field of High-Field
Magnetic resonance imaging system has the characteristics that light-weight, expense is low, easy to maintain, can enter in all kinds of section office as special
Detecting instrument.And corresponding Low Magnetic field MRI high field magnetic resonance signal-to-noise ratio is low, poor image quality, needs various aspects to ensure
The picture quality of equipment.
Radio-frequency coil is an important composition component in magnetic resonance system, is mainly used for emitting radiofrequency signal excitation hydrogen matter
Son generates resonance and receives magnetic resonance signal produced by proton.The RF magnetic field uniformity and RF magnetic field intensity of coil are weighing apparatuses
An important parameter of radio-frequency coil is measured, influences to receive the signal-to-noise ratio of signal and picture quality.
Therefore, the picture quality for the improvement special low field vertical magnetic field magnetic resonance medical imaging devices in head, it is necessary to carry
Go out a kind of radio-frequency coil structure for head imaging, and propose the design method for being optimized to the structure.
Invention content
In view of this, the purpose of the present invention is to provide a kind of radio frequency coil designs methods and line using particle cluster algorithm
Coil structures.
In order to achieve the above objectives, the present invention provides following technical solution：
A kind of radio frequency coil designs method using particle cluster algorithm includes the following steps：
S1：Coil turn range is set, and coil turn n ∈ [a, b] carry out step S2
S2：Coil former parameter population is initialized, Pi carries out step S3
S3：Whether detection coil number of turn n is in section [a, b], if n ∈ [a, b], then carry out step S4；IfThen
Obtain optimal loop construction；
S4：The magnetic field homogeneity and magnetic field intensity in region are calculated according to coil former, each particle is calculated and corresponds to
Fitness Fi, carry out step S5；
S5：The fitness of optimal particle is calculated, if it meets the requirement of optimization object function or reaches greatest iteration step,
Then carry out S6；If it is unsatisfactory for the requirement of optimization object function, step S7 is carried out；
S6：The parameter of optimal particle is recorded, coil turn n is substituted for (n+1), return to step S3；
S7：Update each particle information, return to step S4；
Wherein, a ＜ b, and a, b are positive integer.
Optionally, the optimization object function described in step S5 isWhereinRepresent mesh
Mark magnetic field homogeneity in region, BzAVGFor field strength values in target area, γ is weight coefficient.
Optionally, the particle renewal function described in step S7 is：
vi(t+1)=w × vi(t)+c1×randi(Pi-xi(t))+c2×randi(Qi-xi(t)),
A kind of radio-frequency coil structure using particle cluster algorithm, including n coil, the coaxial of several coils is set
It puts, if the intersection point of plane where first coil and the axis is O, then along the direction far from O points, the radius of coil is gradually reduced,
Uniform magnetic field is formed in the inner space of the radio-frequency coil structure, n is positive integer and n >=2.
Optionally, the radius of first coil is r0, the radius of i-th of coil is ri, in the geometry of i-th of coil
The distance of the heart and O points is hiThe then radius of i-th of coilI is positive integer.
Optionally, it is fixed between adjacent coil by connect band.
Optionally, orthographic projection of the connect band on first coil be point-blank.
Optionally, the inner space of the radio-frequency coil structure and the size of human body head match.
Optionally, the coil includes adjacent magnetic field component units and field compensation unit, first coil to xth
A coil forms magnetic field component units, for establishing RF magnetic field；Remaining coil forms field compensation unit, described for compensating
To form uniform magnetic field, x ＜ n, x are positive integer for RF magnetic field.
Optionally, the inner space of the radio-frequency coil structure is hemispherical.
The beneficial effects of the present invention are：
1st, a kind of radio-frequency coil structure using particle cluster algorithm involved in the present invention is mainly used in human body brain
The magnetic resonance imaging in portion, radio-frequency coil wiring area are selected on a hemisphere face, it is internal formed for wrap up brain half
Spherical hollow space, coil below form magnetic field component units, it is established that the major part of RF magnetic field, above coil use
In compensation magnetic field so that the magnetic field in the specific region inside hemi-spherical cavities tends to be uniform.
2nd, a kind of radio frequency coil designs method using particle cluster algorithm involved in the present invention, passes through regulating winding
Number N and the height where coil carry out the performance of regulating winding, search for optimal coil on a large scale by particle cluster algorithm
Structure is designed instead of traditional blindness test of many times by algorithm, improves design efficiency, the cumbersome journey for alleviating design
Degree improves the designing quality of loop construction.
Other advantages, target and the feature of the present invention will be illustrated in the following description to a certain extent, and
And to a certain extent, based on will be apparent to those skilled in the art to investigating hereafter, Huo Zheke
To be instructed from the practice of the present invention.The target and other advantages of the present invention can by following specification realizing and
It obtains.
Description of the drawings
To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention is made below in conjunction with attached drawing excellent
The detailed description of choosing, wherein：
Fig. 1 is a kind of coil calculation optimization mould of radio-frequency coil structure using particle cluster algorithm involved in the present invention
Type figure；
Fig. 2 is a kind of actual coil connection knot of radio-frequency coil structure using particle cluster algorithm involved in the present invention
Composition；
Fig. 3 is the computation model of space magnetic field caused by single coil；
Fig. 4 is a kind of flow chart of radio frequency coil designs method using particle cluster algorithm involved in the present invention；
Fig. 5 is the field strength analog result before coil optimizes structure；
Fig. 6 is to coil knot using a kind of radio frequency coil designs method using particle cluster algorithm involved in the present invention
Structure optimizes the field strength analog result after structure.
Specific embodiment
Illustrate embodiments of the present invention below by way of specific specific example, those skilled in the art can be by this specification
Disclosed content understands other advantages and effect of the present invention easily.The present invention can also pass through in addition different specific realities
The mode of applying is embodied or practiced, the various details in this specification can also be based on different viewpoints with application, without departing from
Various modifications or alterations are carried out under the spirit of the present invention.It should be noted that diagram provided in following embodiment is only to show
Meaning mode illustrates the basic conception of the present invention, and in the absence of conflict, the feature in following embodiment and embodiment can phase
Mutually combination.
Please refer to Fig.1-Fig. 6, the element numbers in attached drawing represent respectively：Field compensation unit 1, magnetic field component units 2,
One coil 3, the inner space 4 of radio-frequency coil structure, connect band 5.
The present invention relates to a kind of radio frequency coil designs method and loop construction using particle cluster algorithm, described one kind should
With the flow chart of the radio frequency coil designs method of particle cluster algorithm as shown in figure 4, its key step is as follows.
S1：Coil turn range is set, and coil turn n ∈ [a, b] carry out step S2
S2：Coil former parameter population is initialized, Pi carries out step S3
S3：Whether detection coil number of turn n is in section [a, b], if n ∈ [a, b], then carry out step S4；If
Then obtain optimal loop construction；
S4：The magnetic field homogeneity and magnetic field intensity in region are calculated according to coil former, each particle is calculated and corresponds to
Fitness Fi, carry out step S5；
S5：The fitness of optimal particle is calculated, if it meets the requirement of optimization object function or reaches greatest iteration step,
Then carry out S6；If it is unsatisfactory for the requirement of optimization object function, step S7 is carried out；
S6：The parameter of optimal particle is recorded, coil turn n is substituted for (n+1), return to step S3；
S7：Update each particle information, return to step S4；
Wherein, a ＜ b, and a, b are positive integer.
Preferably, the optimization object function described in step S5 isWhereinRepresent mesh
Mark magnetic field homogeneity in region, BzAVGFor field strength values in target area, γ is weight coefficient；Particle described in step S7
Renewal function is：vi(t+1)=w × vi(t)+c1×randi(Pi-xi(t))+c2×randi(Qi-xi(t)),
The superposition in magnetic field produced by space magnetic field caused by the radio-frequency coil can regard multiple single Circumferential coils as, wherein
Single Circumferential coils generated magnetic field in space can be calculated by following formula.
Wherein, r2=x2+y2+z2, ρ2=x2+y2, α2=a2+r2- 2a ρ, k2=1- α2/β2, E (k2)、K(k2) it is oval long-pending
Point.The optimal design parameter of the radio-frequency coil structure is the number of turn n of the Circumferential coils and radius r of each Circumferential coilsi, mainly
For balancing uniformity and magnetic field intensity.Analog result before loop construction optimization is as shown in figure 5, using setting in the present invention
The results are shown in Figure 6 after the progress coil optimization of meter method.Analog result in Fig. 6 is obviously than the field of the analog result in Fig. 5
The strong uniformity is more excellent.
The coil designed using a kind of radio frequency coil designs method using particle cluster algorithm involved in the present invention
Structure is as follows, including n coil, the coaxial arrangement of several coils, if first 3 place plane of coil and the friendship of the axis
Point is O, then along the direction far from O points, the radius of coil is gradually reduced, is formed in the inner space of the radio-frequency coil structure 4
Uniform magnetic field, n are positive integer and n >=2.
Preferably, the radius of first coil 3 is r0, the radius of i-th of coil is ri, in the geometry of i-th of coil
The distance of the heart and O points is hiThe then radius of i-th of coilI is positive integer.
In the present embodiment, it is fixed between adjacent coil by connect band 5；The connect band 5 is in first line
Orthographic projection on circle 3 is point-blank；The inner space 4 of the radio-frequency coil structure and the size phase of human body head
Match；The coil includes adjacent magnetic field component units 2 and field compensation unit 1, first 3 to x-th coil structure of coil
Into magnetic field component units 2, for establishing RF magnetic field；Remaining coil forms field compensation unit 1, for compensating the radio-frequency magnetic
To form uniform magnetic field, x ＜ n, x are positive integer for field；The inner space 4 of the radio-frequency coil structure is hemispherical.
A kind of involved radio-frequency coil structure using particle cluster algorithm is mainly used in human body brain in the present invention
Magnetic resonance imaging, radio-frequency coil wiring area selected on a hemisphere face, the internal hemisphere formed for wrapping up brain
Shape cavity, coil below form magnetic field component units 2, it is established that the major part of RF magnetic field, above coil use
In compensation magnetic field so that the magnetic field in the specific region inside hemi-spherical cavities tends to be uniform.And involved by the present invention
A kind of radio frequency coil designs method using particle cluster algorithm, by the height where the number N and coil of regulating winding come
The performance of regulating winding searches for optimal loop construction by particle cluster algorithm on a large scale, is designed by algorithm instead of biography
The blindness test of many times of system improves design efficiency, the fussy degree for alleviating design, improves the designing quality of loop construction
Finally illustrate, the above embodiments are merely illustrative of the technical solutions of the present invention and it is unrestricted, although with reference to compared with
The present invention is described in detail in good embodiment, it will be understood by those of ordinary skill in the art that, it can be to the skill of the present invention
Art scheme is modified or replaced equivalently, and without departing from the objective and range of the technical program, should all be covered in the present invention
Right in.
Claims (10)
- A kind of 1. radio frequency coil designs method using particle cluster algorithm, which is characterized in that include the following steps：S1：Coil turn range is set, and coil turn n ∈ [a, b] carry out step S2S2：Coil former parameter population is initialized, Pi carries out step S3S3：Whether detection coil number of turn n is in section [a, b], if n ∈ [a, b], then carry out step S4；IfThen obtain Optimal loop construction；S4：The magnetic field homogeneity and magnetic field intensity in region are calculated according to coil former, it is corresponding suitable to calculate each particle Response Fi carries out step S5；S5：The fitness of optimal particle is calculated, if it meets the requirement of optimization object function or reaches greatest iteration step, into Row S6；If it is unsatisfactory for the requirement of optimization object function, step S7 is carried out；S6：The parameter of optimal particle is recorded, coil turn n is substituted for (n+1), return to step S3；S7：Update each particle information, return to step S4；Wherein, a ＜ b, and a, b are positive integer.
- 2. the radio frequency coil designs method of particle cluster algorithm is applied as described in claim 1, which is characterized in that in step S5 The optimization object function isWhereinRepresent magnetic field homogeneity in target area, BzAVG For field strength values in target area, γ is weight coefficient.
- 3. the radio frequency coil designs method of particle cluster algorithm is applied as described in claim 1, which is characterized in that in step S7 The particle renewal function is：
- 4. a kind of radio-frequency coil structure using particle cluster algorithm, which is characterized in that including n coil, several described coils Coaxial arrangement, if the intersection point of plane where first coil and the axis is O, then along the direction far from O points, the radius of coil by It is decrescence small, uniform magnetic field is formed in the inner space of the radio-frequency coil structure, n is positive integer and n >=2.
- 5. the radio-frequency coil structure of particle cluster algorithm is applied as described in claim 4, which is characterized in that first line The radius of circle is r0, the radius of i-th of coil is ri, the geometric center of i-th of coil is h with the distance of O pointsiThen i-th of coil Radius1≤i≤n, i are positive integer.
- 6. as described in claim 4 apply particle cluster algorithm radio-frequency coil structure, which is characterized in that adjacent coil it Between be fixed by connect band.
- 7. the radio-frequency coil structure of particle cluster algorithm is applied as described in claim 5, which is characterized in that the connect band exists Orthographic projection on first coil is point-blank.
- 8. the radio-frequency coil structure of particle cluster algorithm is applied as described in claim 4, which is characterized in that the radio-frequency coil The inner space of structure and the size of human body head match.
- 9. the radio-frequency coil structure of particle cluster algorithm is applied as described in claim 4, which is characterized in that the coil includes Adjacent magnetic field component units and field compensation unit, first coil form magnetic field component units to x-th of coil, are used for Establish RF magnetic field；Remaining coil forms field compensation unit, for compensating the RF magnetic field to form uniform magnetic field, x ＜ N, x are positive integer.
- 10. the radio-frequency coil structure of particle cluster algorithm is applied as described in claim 4, which is characterized in that the radio frequency line The inner space of coil structures is hemispherical.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111639453A (en) * | 2020-06-09 | 2020-09-08 | 福州大学 | Particle swarm algorithm-based magnetic nano thermotherapy alternating magnetic field uniformity optimization method |
| CN112434461A (en) * | 2019-08-23 | 2021-03-02 | 哈尔滨工业大学 | Automatic coupling coil optimization design method for wireless power transmission |
| CN112435837A (en) * | 2020-11-16 | 2021-03-02 | 北京航空航天大学 | Spherical three-dimensional uniform magnetic field coil for SERF atomic magnetic field/inertial measurement sensor |
| CN113506668A (en) * | 2021-06-24 | 2021-10-15 | 北京量子信息科学研究院 | Method for generating uniform magnetic field, magnetic field coil, device, apparatus, and storage medium |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102879753A (en) * | 2012-10-11 | 2013-01-16 | 中国科学院近代物理研究所 | Automatic implementation method for high-uniformity magnet shim coil design |
| US20160334479A1 (en) * | 2015-05-12 | 2016-11-17 | Hyperfine Research, Inc. | Radio frequency coil methods and apparatus |
-
2018
- 2018-01-05 CN CN201810012102.3A patent/CN108182329A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102879753A (en) * | 2012-10-11 | 2013-01-16 | 中国科学院近代物理研究所 | Automatic implementation method for high-uniformity magnet shim coil design |
| US20160334479A1 (en) * | 2015-05-12 | 2016-11-17 | Hyperfine Research, Inc. | Radio frequency coil methods and apparatus |
Non-Patent Citations (6)
| Title |
|---|
| WEIHUA MAO等: "Exploring the Limits of RF Shimming for High-Field MRI", 《MAGNETIC RESONANCE IN MEDICINE》 * |
| 刘杰等: "种群规模自适应控制的中心引力优化", 《北京邮电大学学报》 * |
| 张雯雰等: "粒子群优化算法种群规模的选择", 《计算机系统应用》 * |
| 杨广夫等: "《磁共振诊断学》", 31 May 1991, 陕西科学技术出版社 * |
| 贺玉成等: "一种头部射频线圈的结构优化", 《2017年全国电工理论与新技术学术年会》 * |
| 韩继钧: "基于FDTD/MoM混合方法设计磁共振射频线圈", 《南方医科大学》 * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112434461A (en) * | 2019-08-23 | 2021-03-02 | 哈尔滨工业大学 | Automatic coupling coil optimization design method for wireless power transmission |
| CN112434461B (en) * | 2019-08-23 | 2022-11-04 | 哈尔滨工业大学 | Automatic coupling coil optimization design method for wireless power transmission |
| CN111639453A (en) * | 2020-06-09 | 2020-09-08 | 福州大学 | Particle swarm algorithm-based magnetic nano thermotherapy alternating magnetic field uniformity optimization method |
| CN111639453B (en) * | 2020-06-09 | 2022-09-06 | 福州大学 | Particle swarm algorithm-based magnetic nano thermotherapy alternating magnetic field uniformity optimization method |
| CN112435837A (en) * | 2020-11-16 | 2021-03-02 | 北京航空航天大学 | Spherical three-dimensional uniform magnetic field coil for SERF atomic magnetic field/inertial measurement sensor |
| CN113506668A (en) * | 2021-06-24 | 2021-10-15 | 北京量子信息科学研究院 | Method for generating uniform magnetic field, magnetic field coil, device, apparatus, and storage medium |
| CN113506668B (en) * | 2021-06-24 | 2024-03-01 | 北京量子信息科学研究院 | Method for generating uniform magnetic field, magnetic field coil, device, apparatus, and storage medium |
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