Method and device for determining parameters of artificial electromagnetic material for ultrahigh-field magnetic resonance

Abstract

The invention discloses a method and a device for determining parameters of an artificial electromagnetic material for ultrahigh-field magnetic resonance, which improve the existing design method of the artificial electromagnetic material and improve the design of the artificial electromagnetic material on the basis of originally setting periodic boundary conditions, obtaining scattering coefficients and calculating the effective dielectric constant of the artificial electromagnetic material. The unit structure design of the artificial electromagnetic material in an induction near field region is accurately adjusted by using a microstrip line resonance method; therefore, the artificial electromagnetic material which has the same electrical characteristics as the existing dielectric plate with a high dielectric constant in an antenna induction near-field region can be obtained; therefore, compared with the traditional technology, the artificial electromagnetic material designed by the invention has the advantages that the artifact removal effect can be improved, the blank of the design method of the artificial electromagnetic material with the high dielectric constant in the antenna induction near field area is filled, and the artificial electromagnetic material is very suitable for large-scale application and popularization.

Description

Technical Field

[0001] The present invention belongs to the technical field of artificial electromagnetic material design, and in particular relates to a method and device for determining parameters of artificial electromagnetic materials used for ultra-high field magnetic resonance. Background Art

[0002] The development of modern medicine has given rise to medical imaging technologies such as computed tomography and magnetic resonance imaging. Magnetic resonance imaging (MRI) is a non-invasive, radiation-free technique that is highly safe and can clearly visualize human tissue structure, making it an essential technique for medical diagnosis. Currently, MRI technology has evolved toward higher field strengths and has produced a series of advances. In practical applications, the inhomogeneity of key areas in the radio frequency field at high and ultra-high fields is a significant factor affecting imaging quality. This is because the wavelength within the medium is similar to that of the human body, and phase delay and reflection of electromagnetic waves can cause destructive and constructive interference in local areas, leading to artifacts. This standing wave effect reduces imaging quality, and therefore, improving field uniformity is a crucial aspect of the clinical phase.

[0003] Artificial electromagnetic material structures have dielectric constants and magnetic permeabilities that do not exist in nature. They can regulate and change the propagation direction of electromagnetic waves. They also have the advantages of being light weight, low price, easy to manufacture, stable performance, and material properties that are not easily changed over time. Therefore, the artifact problem caused by the standing wave effect in ultra-high field magnetic resonance imaging can be solved by using artificial electromagnetic materials with high dielectric constants, and in actual tests, the field uniformity has been significantly improved. Based on this, artificial electromagnetic materials are of great significance to improving the signal-to-noise ratio and improving the transmission efficiency.

[0004] Existing design theories and methods for artificial electromagnetic materials are mainly based on the assumption that the object to be measured is located in the radiation zone, that is, by setting periodic boundary conditions and simulating waveguides to obtain scattering parameters, the dielectric constant is further calculated and designed, and the structural parameters of the artificial electromagnetic material are obtained; however, the above methods have the following shortcomings: in a magnetic resonance environment, the imaging object is mainly located in the inductive near-field region of the magnetic resonance radio frequency coil; therefore, the scattering coefficient calculated by the existing method is a parameter reflecting the electrical characteristics of its radiation field, and cannot reflect the true electrical characteristics of the artificial electromagnetic material in the inductive near-field; as such, the artificial electromagnetic material determined by the existing method will have a significant difference in the effect of improving magnetic resonance imaging artifacts compared with a dielectric plate with the same dielectric constant, resulting in poor artifact removal effect; based on this, how to provide a parameter determination method for artificial electromagnetic materials with good artifact removal effect has become an urgent problem to be solved. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and device for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance, so as to solve the problem that the existing technology designs the structural parameters of artificial electromagnetic materials based on the assumption that the object to be measured is located in the radiation zone, resulting in poor artifact removal effect.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, a method for determining parameters of an artificial electromagnetic material for ultra-high field magnetic resonance is provided, which is implemented based on a microstrip line resonant device, wherein the microstrip line resonant device includes a microstrip line substrate and a microstrip line resonant circuit, one end of the microstrip line substrate is provided with a feeding port, and the microstrip line substrate is made of a dielectric plate or an artificial electromagnetic material;

[0008] The microstrip line resonant circuit includes a tuning capacitor, a matching resistor and a microstrip line, wherein the matching resistor is provided at the other end of the microstrip line substrate, one end of the matching resistor is electrically connected to one end of the tuning capacitor through the microstrip line, the other end of the tuning capacitor is electrically connected to the feeding port through the microstrip line, and the other end of the matching resistor is grounded;

[0009] Accordingly, the method includes:

[0010] Obtaining a simulation model of the microstrip line resonant device;

[0011] Under preset conditions, the simulation model is simulated, and when the resonant frequency of the microstrip line in the simulation model reaches a preset frequency, a capacitance value of the tuning capacitor in the simulation model is obtained, wherein the preset condition is that the microstrip line substrate in the simulation model is a preset dielectric plate;

[0012] performing an updating process on the simulation model to update the microstrip line substrate in the simulation model to a target artificial electromagnetic material, thereby obtaining an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate;

[0013] Acquiring multiple sets of initial structural parameters of the target artificial electromagnetic material, and combining each set of initial structural parameters with a capacitance value of a tuning capacitor under preset conditions to obtain multiple sets of simulation parameters;

[0014] Based on multiple sets of simulation parameters, the updated simulation model is simulated multiple times to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip line in the updated simulation model under the any set of simulation parameters;

[0015] From multiple groups of simulation results, simulation results corresponding to resonance point frequencies reaching preset frequencies are screened out, and initial structural parameters in simulation parameters corresponding to the screened out simulation results are used as optimal structural parameters of the target artificial electromagnetic material.

[0016] Based on the above-disclosed content, the present invention determines the parameters of artificial electromagnetic materials by setting up a microstrip line resonant device, wherein the microstrip line resonant device includes a microstrip line substrate, a tuning capacitor, a microstrip line and a matching resistor, and the microstrip line substrate can be a dielectric plate or an artificial electromagnetic material; in this way, the structural parameters of the artificial electromagnetic material can be determined by tuning the capacitor and the microstrip line substrate; specifically, the tuning capacitor, the microstrip line and the resistor jointly simulate the antenna sensing near-field area; therefore, in actual application, a simulation model of the microstrip line resonant device can be obtained first; then, the substrate in the model is set to a preset dielectric plate (that is, a dielectric plate with a known dielectric constant), and a simulation process is performed on it. At the same time, during the simulation process, the capacitance value of the tuning capacitor is adjusted until the resonant point frequency of the microstrip line reaches the required frequency. , the capacitance value at this time can be recorded; then, the substrate in the model can be replaced with the artificial electromagnetic material to be designed, and then the capacitance value of the tuning capacitor can be fixed to the capacitance value recorded above, and combined with different initial structural parameters of the artificial electromagnetic material, simulation processing can be performed to obtain multiple groups of simulation results; finally, it is only necessary to screen out the simulation results corresponding to when the resonant point frequency of the microstrip line reaches the required frequency from the multiple groups of simulation results, and the actual structural parameters of the artificial electromagnetic material can be obtained; that is, the initial structural parameters corresponding to the screened simulation results are used as the optimal structural parameters of the artificial electromagnetic material to be designed; thus, the artificial electromagnetic material with a new structure designed according to this parameter can have the same electrical characteristics as the existing high dielectric constant dielectric plate in the antenna sensing near field.

[0017] Through the above design, the present invention improves the existing design method of artificial electromagnetic materials. On the basis of setting periodic boundary conditions and obtaining the scattering coefficient to calculate the equivalent dielectric constant of the artificial electromagnetic material, the unit structure design of the artificial electromagnetic material in the inductive near-field region is precisely adjusted by utilizing the microstrip line resonance method. In this way, an artificial electromagnetic material having the same electrical properties as the existing high-dielectric-constant dielectric plate in the antenna inductive near-field region can be obtained. Therefore, compared with traditional technologies, the artificial electromagnetic material designed by the present invention can improve the artifact removal effect and fill the gap in the design method of artificial electromagnetic materials with high dielectric constants in the antenna inductive near-field region, making it very suitable for large-scale application and promotion.

[0018] In a possible design, the transmission line characteristic impedance of the matching resistor is 50 ohms.

[0019] In one possible design, the tuning capacitor is located above the microstrip line substrate.

[0020] In one possible design, one end of the feeding port that is not connected to the microstrip line is grounded.

[0021] In one possible design, the target artificial electromagnetic material includes: a first metal layer, a first dielectric layer, a second metal layer, and a second dielectric layer arranged in sequence from top to bottom.

[0022] In a possible design, the first metal layer includes a plurality of copper sheet units, the second metal layer includes a copper sheet, and the first dielectric layer and the second dielectric layer both use FR-4 dielectric boards.

[0023] In one possible design, the first metal layer includes four copper sheet units, and the four copper sheet units are arranged in a matrix.

[0024] In a second aspect, a device for determining parameters of an artificial electromagnetic material for ultra-high field magnetic resonance is provided, which is implemented based on a microstrip line resonant device, wherein the microstrip line resonant device includes a microstrip line substrate and a microstrip line resonant circuit, one end of the microstrip line substrate is provided with a feeding port, and the microstrip line substrate is made of a dielectric plate or an artificial electromagnetic material;

[0025] The microstrip line resonant circuit includes a tuning capacitor, a matching resistor and a microstrip line, wherein the matching resistor is provided at the other end of the microstrip line substrate, one end of the matching resistor is electrically connected to one end of the tuning capacitor through the microstrip line, the other end of the tuning capacitor is electrically connected to the feeding port through the microstrip line, and the other end of the matching resistor is grounded;

[0026] Accordingly, the parameter determination device includes:

[0027] A model acquisition unit, configured to acquire a simulation model of the microstrip line resonant device;

[0028] a model simulation unit, configured to simulate the simulation model under preset conditions and obtain a capacitance value of a tuning capacitor in the simulation model when a resonant frequency of a microstrip line in the simulation model reaches a preset frequency, wherein the preset condition is that a microstrip line substrate in the simulation model is a preset dielectric plate;

[0029] a model updating unit, configured to update the simulation model to update the microstrip line substrate in the simulation model to a target artificial electromagnetic material, thereby obtaining an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate;

[0030] a parameter combination unit, configured to obtain multiple sets of initial structural parameters of the target artificial electromagnetic material, and combine each set of initial structural parameters with a capacitance value of a tuning capacitor under preset conditions to obtain multiple sets of simulation parameters;

[0031] The model simulation unit is further configured to perform multiple simulation processes on the updated simulation model based on multiple sets of simulation parameters to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip in the updated simulation model under the any set of simulation parameters;

[0032] The parameter determination unit is used to screen out simulation results corresponding to the resonant point frequency reaching the preset frequency from multiple groups of simulation results, and use the initial structural parameters in the simulation parameters corresponding to the screened simulation results as the optimal structural parameters of the target artificial electromagnetic material.

[0033] In a third aspect, another device for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance is provided. Taking the device as an electronic device as an example, the device includes a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect or any possible design of the first aspect.

[0034] In a fourth aspect, a storage medium is provided, on which instructions are stored. When the instructions are run on a computer, the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect or any possible design of the first aspect is executed.

[0035] In a fifth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, causes the computer to execute the method for determining parameters of an artificial electromagnetic material for ultra-high field magnetic resonance as described in the first aspect or any possible design of the first aspect.

[0036] Beneficial effects:

[0037] (1) The present invention improves the existing design method of artificial electromagnetic materials. On the basis of setting periodic boundary conditions and obtaining the scattering coefficient to calculate the equivalent dielectric constant of the artificial electromagnetic material, the microstrip line resonance method is used to accurately adjust the unit structure design of the artificial electromagnetic material in the inductive near field. In this way, an artificial electromagnetic material having the same electrical properties as the existing high dielectric constant dielectric plate in the antenna inductive near field can be obtained. Therefore, compared with the traditional technology, the artificial electromagnetic material designed by the present invention can improve the de-artifacting effect and fill the gap in the design method of artificial electromagnetic materials with high dielectric constants in the antenna inductive near field, and is very suitable for large-scale application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of the three-dimensional structure of a microstrip line resonant device provided in an embodiment of the present invention;

[0039] Figure 2 A side view of a microstrip line resonant device provided by an embodiment of the present invention;

[0040] Figure 3 A schematic flow chart of the steps of a method for determining parameters of an artificial electromagnetic material for ultra-high field magnetic resonance provided by an embodiment of the present invention;

[0041] Figure 4 A schematic structural diagram of the target artificial electromagnetic material provided by an embodiment of the present invention;

[0042] Figure 5 A schematic diagram of an application of the target artificial electromagnetic material provided by an embodiment of the present invention;

[0043] Figure 6 A schematic structural diagram of a device for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance provided by an embodiment of the present invention;

[0044] Figure 7 A schematic structural diagram of an electronic device provided by an embodiment of the present invention.

[0045] Reference numerals:

[0046] 10-microstrip line substrate; 20-feeding port; 30-tuning capacitor; 40-matching resistor; 50-microstrip line; 60-first metal layer; 70-first dielectric layer; 80-second metal layer; 90-second dielectric layer. DETAILED DESCRIPTION

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be briefly introduced below in conjunction with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0048] It should be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element without departing from the scope of the exemplary embodiments of the present invention.

[0049] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B may indicate three situations: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" that may appear in this document describes another type of association object relationship, indicating that two relationships may exist. For example, A / and B may indicate two situations: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this document generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0050] Example:

[0051] See also Figures 1 to 5 As shown, the parameter determination method of the artificial electromagnetic material for ultra-high field magnetic resonance provided by this embodiment is implemented based on a microstrip line resonant device. Before describing this method, the specific structure of the aforementioned microstrip line resonant device is first disclosed; its structural diagram can be found in Figure 1 and Figure 2 shown.

[0052] In this embodiment, the microstrip line resonant device may include, but is not limited to: a microstrip line substrate 10 and a microstrip line resonant circuit, wherein, see Figure 1 As shown, a feeding port 20 is provided at one end of the microstrip line substrate 10, and the microstrip line substrate 10 adopts a dielectric plate or an artificial electromagnetic material; optionally, whether a dielectric plate or an artificial electromagnetic material is adopted, the dielectric constant of the microstrip line substrate is a high dielectric constant (greater than a preset value, and the preset value can be specifically set according to actual use); in this way, the structural parameters of the target artificial electromagnetic material can be determined based on the replacement of the microstrip line substrate and the microstrip line resonant circuit.

[0053] At the same time, the following discloses one circuit structure of a microstrip line resonant circuit:

[0054] See also Figure 1 Shown and Figure 2 As shown, for example, the microstrip line resonant circuit may include, but is not limited to: a tuning capacitor 30, a matching resistor 40 and a microstrip line 50; wherein, the specific connection structure of the aforementioned electronic devices is: the matching resistor 40 is arranged at the other end of the microstrip line substrate 10 (the feeding port 20 can be arranged on the left side of the substrate, the matching resistor 40 can be arranged on the right side of the substrate, and its transmission line characteristic impedance can be, but is not limited to, set to 50 ohms), and the tuning capacitor 30 is located above the microstrip line substrate 10; at the same time, one end of the matching resistor 40 is electrically connected to one end of the tuning capacitor 30 through the microstrip line 50, and the other end of the tuning capacitor 30 is electrically connected to the feeding port 20 through the microstrip line 50, and the other end of the matching resistor 40 and the end of the feeding port 20 not connected to the microstrip line 50 are grounded respectively.

[0055] In this way, through the above design, the tuning capacitor in the microstrip line resonant device and the replaceable microstrip line substrate can be used to perform simulation processing, thereby determining the optimal structural parameters of the target artificial electromagnetic material, and based on the optimal structural parameters, an artificial electromagnetic material with the same electrical characteristics as the existing high dielectric constant dielectric plate in the antenna inductive near field region can be designed.

[0056] For details, see Figure 3 As shown, the parameter determination method of the artificial electromagnetic material based on the aforementioned microstrip line resonant device can be, but is not limited to, run on the artificial electromagnetic material design end side. Optionally, the artificial electromagnetic material design end can be, but is not limited to, a personal computer (PC). It can be understood that the aforementioned execution subject does not constitute a limitation on the embodiments of the present application. Accordingly, the operation steps of this method can be, but are not limited to, as shown in the following steps S1 to S5.

[0057] S1. Under preset conditions, the simulation model is simulated, and when the frequency of the resonance point of the microstrip line 50 in the simulation model reaches a preset frequency, the capacitance value of the tuning capacitor 30 in the simulation model is obtained, wherein the preset condition is that the microstrip line substrate 10 in the simulation model is a preset dielectric plate; in this embodiment, it is equivalent to setting the microstrip line substrate 10 in the simulation model of the microstrip line resonant device as a dielectric plate with a known dielectric constant based on the artificial electromagnetic material design end, and based on this, performing simulation processing; wherein, during the simulation process, the capacitance value of the tuning capacitor 30 is continuously adjusted, and then the frequency of the resonance point of the microstrip line 50 in the model is obtained until its frequency When the design requirements are met (the frequency of the design requirements can be specifically set according to the actual usage scenario), the simulation can be ended; at this time, the capacitance value at this time can be recorded; in this way, the capacitance value can be fixed, and then the microstrip line substrate 10 in the simulation model is replaced with the artificial electromagnetic material to be designed (i.e., the target artificial electromagnetic material described below). Then, by changing the structural parameters of the target artificial electromagnetic material in the model, multiple simulation processes are performed until the resonant point frequency of the microstrip line 50 in the model meets the design requirements, and the optimal structural parameters of the target artificial electromagnetic material can be obtained; wherein, the process of determining the optimal structural parameters can be, but is not limited to, as shown in the following steps S2 to S5.

[0058] S2. The simulation model is updated to update the microstrip line substrate 10 in the simulation model to a target artificial electromagnetic material, thereby obtaining an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate. In this embodiment, step S2 is a process of updating the microstrip line substrate 10, i.e., updating it to the artificial electromagnetic material to be designed, so as to perform subsequent simulation processing and thereby obtain its optimal structural parameters.

[0059] Optionally, the target artificial electromagnetic material may include, but is not limited to, a first metal layer 60, a first dielectric layer 70, a second metal layer 80, and a second dielectric layer 90 arranged in sequence from top to bottom. The structural diagram thereof can be seen in FIG. Figure 4 As shown; For example, the first metal layer 60 includes a plurality of copper sheet units (such as four copper sheet units, and the four copper sheet units are arranged in a matrix), and the second metal layer 80 includes a copper sheet (the copper sheet is a whole copper sheet, which can be seen in FIG. Figure 4 As shown), and the first dielectric layer 70 and the second dielectric layer 90 both use FR-4 dielectric boards; thus, the following simulation process needs to determine the optimal structural parameters of the target artificial electromagnetic material, including but not limited to the side length of each layer, the arrangement period of each layer, etc.

[0060] Furthermore, the simulation process is shown in the following steps S3 and S4.

[0061] S3. Acquire multiple sets of initial structural parameters of the target artificial electromagnetic material, and combine each set of initial structural parameters with the capacitance value of the tuning capacitor 30 under preset conditions to obtain multiple sets of simulation parameters; in specific applications, the initial structural parameters of the target artificial electromagnetic material may include but are not limited to size, arrangement period of each layer, etc.; in this way, the multiple sets of initial structural parameters and the capacitance value of the tuning capacitor 30 under preset conditions can be used to combine to obtain multiple sets of simulation parameters; then, the multiple sets of simulation parameters can be used to simulate the updated simulation model, and the process is shown in the following step S4.

[0062] S4. Based on multiple sets of simulation parameters, the updated simulation model is simulated multiple times to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip line 50 in the updated simulation model under any set of simulation parameters; in specific implementation, it is equivalent to setting multiple sets of initial structural parameters, and then, when the capacitance value of the tuning capacitor 30 is the capacitance value obtained in the aforementioned step S1, multiple simulations are performed, and the resonant point frequency of the microstrip line 50 in the updated simulation model is recorded during each simulation, thereby obtaining simulation results corresponding to each set of simulation parameters; finally, the optimal structural parameters of the target artificial electromagnetic material can be determined based on the multiple sets of simulation results, and the determination process is shown in the following step S5.

[0063] S5. Filter out simulation results corresponding to the resonant point frequency reaching the preset frequency from the multiple sets of simulation results, and use the initial structural parameters in the simulation parameters corresponding to the filtered simulation results as the optimal structural parameters of the target artificial electromagnetic material.

[0064] The following uses an example to illustrate the aforementioned steps S1 to S5:

[0065] Assume that it is necessary to design an artificial electromagnetic material for the 297.2 MHz application scenario in 7T magnetic resonance imaging. Then, a dielectric plate with a known dielectric constant is first used as the substrate of the microstrip line resonant device (such as a dielectric material with a dielectric constant of 78.4). Then, the simulation model is simulated, and the capacitance value of the tuning capacitor 30 is changed during the simulation until the resonant point frequency of the microstrip line 50 is tuned to 297.2 MHz, at which point the capacitance value is fixed.

[0066] Next, the microstrip line substrate 10 in the simulation model is replaced with the target artificial electromagnetic material to obtain an updated simulation model. Of course, the dielectric constant of the target artificial electromagnetic material is also 78.4 (which can be designed using the existing periodic boundary design method); then, multiple simulation processes are performed under different initial structural parameters, and the resonance point frequency of the microstrip line 50 is recorded when each set of initial structural parameters is simulated, thereby obtaining the simulation results corresponding to each set of initial structural parameters; finally, the initial structural parameters corresponding to the simulation result with a resonance point frequency of 297.2 MHz can be used as the optimal structural parameters of the target artificial electromagnetic material; based on this, the target artificial electromagnetic material designed using the optimal structural parameters can have the same electrical characteristics as the existing high dielectric constant dielectric plate in the antenna sensing near field.

[0067] In addition, this embodiment provides a schematic diagram of the application of the target artificial electromagnetic material designed based on the optimal structural parameters, see Figure 5 As shown, Figure 5 This is a schematic diagram of placing the target artificial electromagnetic material into the birdcage coil inductive near field area. Figure 5 The middle and outer parts are birdcage coils excited by standing waves, the cylinder inside is a water model simulating the human head, and the rectangular structure in front of the cylinder is the artificial electromagnetic material structure designed in this embodiment, which is used to improve the field non-uniformity problem under ultra-high fields, thereby achieving a good artifact removal effect.

[0068] Therefore, through the parameter determination method of artificial electromagnetic materials for ultra-high field magnetic resonance described in detail above, the present invention improves the existing design method of artificial electromagnetic materials. On the basis of setting periodic boundary conditions and obtaining the scattering coefficient to calculate the equivalent dielectric constant of the artificial electromagnetic material, the unit structure design of the artificial electromagnetic material in the inductive near-field region is precisely adjusted by utilizing the microstrip line resonance method. In this way, an artificial electromagnetic material having the same electrical properties as the existing high dielectric constant dielectric plate in the antenna inductive near-field region can be obtained. Therefore, compared with traditional technologies, the artificial electromagnetic material designed by the present invention can improve the artifact removal effect and fill the gap in the design method of artificial electromagnetic materials with high dielectric constants in the antenna inductive near-field region, and is very suitable for large-scale application and promotion.

[0069] like Figure 6 As shown, the second aspect of this embodiment provides a hardware device for implementing the parameter determination method of the artificial electromagnetic material for ultra-high field magnetic resonance described in the first aspect of the embodiment, which is implemented based on the microstrip line resonant device in the first aspect of the aforementioned embodiment (its structure has been described in the first aspect of the embodiment and will not be repeated here), wherein the device includes:

[0070] A model acquisition unit, configured to acquire a simulation model of the microstrip line resonant device;

[0071] The model simulation unit is used to simulate the simulation model under preset conditions and obtain the capacitance value of the tuning capacitor 30 in the simulation model when the resonance point frequency of the microstrip line 50 in the simulation model reaches a preset frequency, wherein the preset condition is that the microstrip line substrate 10 in the simulation model is a preset dielectric plate.

[0072] The model updating unit is used to update the simulation model to update the microstrip line substrate 10 in the simulation model to a target artificial electromagnetic material to obtain an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate.

[0073] The parameter combination unit is used to obtain multiple groups of initial structural parameters of the target artificial electromagnetic material, and combine each group of initial structural parameters with the capacitance value of the tuning capacitor 30 under preset conditions to obtain multiple groups of simulation parameters.

[0074] The model simulation unit is further configured to perform multiple simulation processes on the updated simulation model based on multiple sets of simulation parameters to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip line 50 in the updated simulation model under the any set of simulation parameters;

[0075] The parameter determination unit is used to screen out simulation results corresponding to the resonant point frequency reaching the preset frequency from multiple groups of simulation results, and use the initial structural parameters in the simulation parameters corresponding to the screened simulation results as the optimal structural parameters of the target artificial electromagnetic material.

[0076] The working process, working details and technical effects of the device provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0077] like Figure 7 As shown, the third aspect of this embodiment provides another device for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance. Taking the device as an electronic device as an example, it includes: a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect of the embodiment.

[0078] For example, the memory may include, but is not limited to, random access memory (RAM), read-only memory (ROM), flash memory, first-in first-out memory (FIFO), and / or first-in last-out memory (FILO); specifically, the processor may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. The processor may be implemented in at least one hardware form selected from DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). Furthermore, the processor may include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); and the coprocessor is a low-power processor for processing data in a standby state.

[0079] In some embodiments, the processor may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. For example, the processor may be, but is not limited to, a microprocessor of the STM32F105 series, a reduced instruction set computer (RISC) microprocessor, an X86 architecture processor, or a processor with an integrated embedded neural network processing unit (NPU); the transceiver may be, but is not limited to, a wireless fidelity (WIFI) wireless transceiver, a Bluetooth wireless transceiver, a general packet radio service technology (GPRS) wireless transceiver, a ZigBee protocol (a low-power local area network protocol based on the IEEE802.15.4 standard, ZigBee) wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver. In addition, the device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0080] The working process, working details and technical effects of the electronic device provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0081] A fourth aspect of this embodiment provides a storage medium storing instructions for the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect of the embodiment, that is, the storage medium stores instructions, and when the instructions are run on a computer, the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect of the embodiment is executed.

[0082] The storage medium refers to a carrier for storing data, which may include but is not limited to a floppy disk, an optical disk, a hard disk, a flash memory, a USB flash drive and / or a memory stick, and the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0083] The working process, working details and technical effects of the storage medium provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0084] A fifth aspect of this embodiment provides a computer program product comprising instructions, which, when executed on a computer, causes the computer to execute the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance as described in the first aspect of the embodiment, wherein the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0085] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance, characterized in that: The invention is realized based on a microstrip line resonant device, wherein the microstrip line resonant device comprises a microstrip line substrate (10) and a microstrip line resonant circuit, one end of the microstrip line substrate (10) is provided with a feeding port (20), and the microstrip line substrate (10) adopts a dielectric plate or an artificial electromagnetic material; The microstrip line resonant circuit comprises a tuning capacitor (30), a matching resistor (40) and a microstrip line (50), wherein the matching resistor (40) is arranged at the other end of the microstrip line substrate (10), one end of the matching resistor (40) is electrically connected to one end of the tuning capacitor (30) through the microstrip line (50), the other end of the tuning capacitor (30) is electrically connected to the feeding port (20) through the microstrip line (50), and the other end of the matching resistor (40) is grounded; Accordingly, the method includes: Obtaining a simulation model of the microstrip line resonant device; Under preset conditions, the simulation model is simulated, and when the resonance point frequency of the microstrip line (50) in the simulation model reaches a preset frequency, the capacitance value of the tuning capacitor (30) in the simulation model is obtained, wherein the preset condition is that the microstrip line substrate (10) in the simulation model is a preset dielectric plate; The simulation model is updated to update the microstrip line substrate (10) in the simulation model to a target artificial electromagnetic material, thereby obtaining an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate; Acquiring multiple sets of initial structural parameters of the target artificial electromagnetic material, and combining each set of initial structural parameters with the capacitance value of the tuning capacitor (30) under preset conditions to obtain multiple sets of simulation parameters; Based on multiple sets of simulation parameters, multiple simulation processes are performed on the updated simulation model to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip line (50) in the updated simulation model under the any set of simulation parameters; From multiple groups of simulation results, simulation results corresponding to resonance point frequencies reaching preset frequencies are screened out, and initial structural parameters in simulation parameters corresponding to the screened out simulation results are used as optimal structural parameters of the target artificial electromagnetic material.

2. The method according to claim 1, characterized in that The transmission line characteristic impedance of the matching resistor (40) is 50 ohms.

3. The method according to claim 1, characterized in that The tuning capacitor (30) is located above the microstrip line substrate (10).

4. The method according to claim 1, wherein One end of the feeding port (20) not connected to the microstrip line (50) is grounded.

5. The method according to claim 1, characterized in that The target artificial electromagnetic material comprises: a first metal layer (60), a first dielectric layer (70), a second metal layer (80), and a second dielectric layer (90) arranged in sequence from top to bottom.

6. The method according to claim 5, characterized in that The first metal layer (60) includes a plurality of copper sheet units, the second metal layer (80) includes a copper sheet, and the first dielectric layer (70) and the second dielectric layer (90) both use FR-4 dielectric boards.

7. The method according to claim 6, characterized in that The first metal layer (60) comprises four copper sheet units, and the four copper sheet units are arranged in a matrix.

8. A device for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance, characterized in that: The invention is realized based on a microstrip line resonant device, wherein the microstrip line resonant device comprises a microstrip line substrate (10) and a microstrip line resonant circuit, one end of the microstrip line substrate (10) is provided with a feeding port (20), and the microstrip line substrate (10) adopts a dielectric plate or an artificial electromagnetic material; The microstrip line resonant circuit comprises a tuning capacitor (30), a matching resistor (40) and a microstrip line (50), wherein the matching resistor (40) is arranged at the other end of the microstrip line substrate (10), one end of the matching resistor (40) is electrically connected to one end of the tuning capacitor (30) through the microstrip line (50), the other end of the tuning capacitor (30) is electrically connected to the feeding port (20) through the microstrip line (50), and the other end of the matching resistor (40) is grounded; Accordingly, the parameter determination device includes: A model acquisition unit, configured to acquire a simulation model of the microstrip line resonant device; A model simulation unit is used to simulate the simulation model under preset conditions and obtain the capacitance value of the tuning capacitor (30) in the simulation model when the resonance point frequency of the microstrip line (50) in the simulation model reaches a preset frequency, wherein the preset condition is that the microstrip line substrate (10) in the simulation model is a preset dielectric plate; A model updating unit is used to update the simulation model to update the microstrip line substrate (10) in the simulation model to a target artificial electromagnetic material to obtain an updated simulation model, wherein the dielectric constant of the target artificial electromagnetic material is the same as the dielectric constant of the preset dielectric plate; A parameter combination unit is used to obtain multiple groups of initial structural parameters of the target artificial electromagnetic material, and combine each group of initial structural parameters with the capacitance value of the tuning capacitor (30) under preset conditions to obtain multiple groups of simulation parameters; The model simulation unit is further configured to perform multiple simulation processes on the updated simulation model based on multiple sets of simulation parameters to obtain simulation results corresponding to each set of simulation parameters, wherein the simulation results corresponding to any set of simulation parameters include the resonant point frequency of the microstrip line (50) in the updated simulation model under the any set of simulation parameters; The parameter determination unit is used to screen out simulation results corresponding to the resonant point frequency reaching the preset frequency from multiple groups of simulation results, and use the initial structural parameters in the simulation parameters corresponding to the screened simulation results as the optimal structural parameters of the target artificial electromagnetic material.

9. An electronic device, characterized in that: include: A memory, a processor, and a transceiver that are sequentially communicatively connected, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the method for determining parameters of an artificial electromagnetic material for ultra-high field magnetic resonance according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium stores instructions, and when the instructions are executed on a computer, the method for determining parameters of artificial electromagnetic materials for ultra-high field magnetic resonance according to any one of claims 1 to 7 is executed.

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