Method and device for simulating terahertz wave scattering characteristics of plasma-coated targets

Abstract

The present invention relates to the field of optics, and in particular to a method and device for simulating the terahertz wave scattering characteristics of a plasma-coated target. The present invention constructs a two-dimensional model using the geometric parameters of a plasma region and its coated target, and simultaneously assigns corresponding material properties to the two-dimensional model, thereby obtaining a physical model. The characteristic parameters of the plasma are introduced into the plasma region of the physical model, thereby obtaining a simulation model of the terahertz wave scattering characteristics of the plasma-coated target. Finite element simulation calculations are performed using the simulation model to obtain the electric field distribution of the plasma-coated target. The complete terahertz wave scattering characteristics of the plasma-coated target can then be determined by comparing the electric fields scattered in all directions by the target with the electric field in the incoming wave direction. The present invention can help researchers quickly understand the terahertz wave scattering characteristics of plasma-coated targets.

Description

Technical Field

[0001] The present invention relates to the field of optics, and in particular to a method and device for simulating terahertz wave scattering characteristics of a plasma-coated target. Background Art

[0002] When electromagnetic waves encounter a plasma sheath during propagation, they are absorbed and attenuated, and deflection, delay, phase shift and other effects occur. In severe cases, a "black barrier" appears. The appearance of a "black barrier" brings great difficulties to the measurement, control and communication of high-speed aircraft.

[0003] In related technologies, terahertz wave scattering measurement systems are often complex and have a small dynamic range, resulting in inaccurate simulation results of the terahertz wave scattering characteristics of plasma-coated targets.

[0004] Based on this, there is an urgent need for a simulation method and device for the terahertz wave scattering characteristics of a plasma-coated target to solve the technical problem of how to quickly grasp the terahertz wave scattering characteristics of a plasma-coated target. Summary of the Invention

[0005] In order to solve the technical problem of how to quickly grasp the terahertz wave scattering characteristics of a plasma-coated target, an embodiment of the present invention provides a method and apparatus for simulating the terahertz wave scattering characteristics of a plasma-coated target.

[0006] In a first aspect, an embodiment of the present invention provides a method for simulating terahertz wave scattering characteristics of a plasma-coated target, comprising:

[0007] Acquiring geometric parameters of the plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma;

[0008] Based on the geometric parameters, a two-dimensional model of the plasma-coated target is determined, and corresponding material properties are assigned to the two-dimensional model to obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, the plasma region enveloping the target body region, and the free space region enveloping the plasma region;

[0009] Bringing the characteristic parameters into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target;

[0010] Finite element simulation calculations are performed using the simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric fields scattered in all directions;

[0011] The electric fields scattered in all directions are compared with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

[0012] In a second aspect, an embodiment of the present invention further provides a device for simulating terahertz wave scattering characteristics of a plasma-coated target, comprising:

[0013] An acquisition module, configured to acquire geometric parameters of a plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma;

[0014] a first model building module, configured to determine a two-dimensional model of the plasma-coated target based on the geometric parameters, and assign corresponding material properties to the two-dimensional model to obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, wherein the plasma region encloses the target body region, and the free space region encloses the plasma region;

[0015] A second model building module is used to bring the characteristic parameters into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target;

[0016] A first data processing module is configured to perform finite element simulation calculations using a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain an electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric fields scattered in all directions;

[0017] The second data processing module is used to compare the electric field scattered in all directions with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

[0018] In a third aspect, an embodiment of the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method described in any embodiment of the present invention is implemented.

[0019] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method described in any embodiment of the present invention.

[0020] An embodiment of the present invention provides a method and apparatus for simulating the terahertz wave scattering characteristics of a plasma-coated target. First, a two-dimensional model is constructed based on the geometric parameters of the plasma-coated target, and corresponding material properties are assigned to the two-dimensional model to obtain a physical model. Subsequently, characteristic parameters are introduced into the plasma region of the physical model to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-coated target. This model can be used to simulate the transmission conditions of the terahertz waves of the plasma-coated target. Next, simulation calculations are performed using the simulation model of the terahertz wave scattering characteristics of the plasma-coated target to obtain the electric field distribution of the plasma-coated target. Finally, the terahertz wave scattering characteristics of the plasma-coated target are indirectly determined based on the incoming wave direction and the electric field scattered in various directions. This overcomes the complexity and small dynamic range problems of existing terahertz transmission measurement systems and solves the technical problem of how to quickly determine the terahertz wave scattering characteristics of the plasma-coated target. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a flow chart of a method for simulating terahertz wave scattering characteristics of a plasma-coated target provided by an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of a terahertz wave scattering characteristic model of a plasma-coated blunt body target provided by an embodiment of the present invention;

[0024] Figure 3 is a schematic diagram of an externally introduced non-uniform plasma electron density distribution provided by an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the scattered electric field distribution of a terahertz wave by a plasma-coated copper blunt body provided by an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the radiation direction of terahertz waves by a plasma-coated copper bluff body provided by an embodiment of the present invention;

[0027] Figure 6 This is a hardware architecture diagram of an electronic device provided by an embodiment of the present invention;

[0028] Figure 7This is a structural diagram of a device for simulating the terahertz wave scattering characteristics of a plasma-coated target provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] Please refer to Figure 1 An embodiment of the present invention provides a method for simulating terahertz wave scattering characteristics of a plasma-coated target, the method comprising:

[0031] Step 100: Acquire geometric parameters of the plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma;

[0032] Step 102: Determine a two-dimensional model of the plasma-coated target based on the geometric parameters, assign corresponding material properties to the two-dimensional model, and obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, wherein the plasma region encapsulates the target body region, and the free space region encapsulates the plasma region;

[0033] Step 104: Bringing the characteristic parameters into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target;

[0034] Step 106: Performing finite element simulation calculations using a simulation model of the terahertz wave scattering characteristics of a plasma-encapsulated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric fields scattered in all directions;

[0035] Step 108: Compare the electric fields scattered in all directions with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

[0036] In an embodiment of the present invention, first, a two-dimensional model is constructed based on the geometric parameters of the plasma-coated target, and corresponding material properties are assigned to the two-dimensional model to obtain a physical model. Subsequently, characteristic parameters are introduced into the plasma region of the physical model to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-coated target. This model can be used to simulate the transmission conditions of the terahertz waves of the plasma-coated target. Next, simulation calculations are carried out using the simulation model of the terahertz wave scattering characteristics of the plasma-coated target to obtain the electric field distribution of the plasma-coated target. Finally, the terahertz wave scattering characteristics of the plasma-coated target are indirectly determined by the incoming wave direction and the electric field scattered in various directions. In this way, the problems of complexity and small dynamic range of existing terahertz wave transmission measurement systems are overcome, and the technical problem of how to increase the speed of solving the terahertz wave scattering characteristics of plasma-coated targets is solved.

[0037] Described below Figure 1 How to perform the steps shown.

[0038] For step 100:

[0039] In one embodiment of the present invention, the characteristic parameters of the plasma can be collected by a laser Thomson scattering measurement system. The Thomson scattering (TS) signal acquisition system is mainly composed of a lens combination, a linear fiber bundle, a spectrometer (TGS) with three gratings, and a charge-coupled device camera (ICCD). The fiber collection direction, the laser direction, and the plasma beam axis are all at a right angle of 90 degrees. A set of convex lens combinations set at the front end of the fiber can accurately focus the area where the laser and plasma interact at the fiber entrance. Subsequently, the Thomson scattering signal collected by the fiber will be transmitted to the TGS system. Within the TGS system, it will be processed by a series of optical devices such as gratings and lenses, and finally imaged (spectrally) on the ICCD camera. To avoid interference with the measurement caused by Rayleigh scattering generated by the air and reflections from the surfaces of other objects, the collection end of the fiber and the collection lens are placed in a darkroom. By performing laser Thomson scattering measurements on the plasma, the distribution of the characteristic parameters of the plasma can be directly obtained.

[0040] In one embodiment of the present invention, a Langmuir probe can be used to measure the electron density of a plasma. Specifically, a very small electrode is inserted into the plasma, a specific voltage is applied, and the relationship between the current flowing through the electrode and the applied voltage is measured. By analyzing specific points on the voltage-current characteristic curve, the electron density of the plasma can be calculated.

[0041] In one embodiment of the present invention, a laser scanning device can be used to collect the geometric parameters of a plasma-encapsulated target. First, it is necessary to ensure that the laser beam completely covers all areas of the plasma-encapsulated target that need to be measured. Next, a scanning program is initiated, and the reflected light signal is recorded. During the data processing phase, the coordinates of each point on the surface of the plasma-encapsulated target are calculated based on relevant parameters such as the angle and time of the laser scan, combined with a model of the optical properties of the plasma. In this way, the geometric parameters of the plasma-encapsulated target, such as length, width, and flatness, can be obtained.

[0042] Regarding step 102:

[0043] In one embodiment of the present invention, appropriate 2D modeling software, such as CAD, is selected based on the collected geometric parameters, including the length, width, and thickness of the plasma-coated target. A new 2D model file is created in the software, and the model's units are appropriately set to ensure they match the units of the geometric parameters. Subsequently, the corresponding material properties are assigned to the 2D model to obtain a physical model. Those skilled in the art can customize the material properties based on the actual use case; for example, the properties of materials such as ceramics and copper can be set as needed.

[0044] like Figure 2 As shown in the figure, in one embodiment of the present invention, the plasma region surrounds the target body region, and the free space region surrounds the plasma region (blue area). The left side of the free space region is the entrance of the terahertz wave. The terahertz wave enters from the free space region and irradiates the plasma-enclosed target, where it interacts with the plasma and the target body, causing scattering of the wave.

[0045] Regarding step 104:

[0046] like Figure 3 As shown, in one embodiment of the present invention, it is the characteristic parameter distribution of the plasma region, and the characteristic parameters are enhanced from blue to red. The characteristic parameters are introduced into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-enclosed blunt body target, which is used to simulate the terahertz wave transmission of the plasma-enclosed blunt body target. By defining variables, the plasma electron density (the collision frequency is sometimes a certain value, sometimes a distribution data) obtained by external measurement or simulation is imported into the blue plasma region in the model in the form of an interpolation function. In addition to the plasma region, the corresponding materials of the free space region and the target body region in the model are selected and set. The wall is layered and divided into appropriate grids.

[0047] Regarding step 106:

[0048] In one embodiment of the present invention, step 106 may specifically include:

[0049] Based on the characteristic parameters, the equivalent dielectric constant of the plasma is determined;

[0050] Solve Maxwell's equations based on the equivalent dielectric constant;

[0051] Based on Maxwell's equations, the electric field distribution is determined.

[0052] In this embodiment, the equivalent dielectric constant is determined by the following formula:

[0053]

[0054] Where, ε p is the equivalent dielectric constant, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma; n e is the electron density; e is the electron charge; m e The mass of the electron.

[0055] In this embodiment, Maxwell's equations are:

[0056]

[0057] Where, ε p is the equivalent dielectric constant, j is the imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field strength vector, is the electric field strength vector.

[0058] In this embodiment, the terahertz electromagnetic wave propagates in the plasma along the z-axis of the spatial coordinate system, while the electric field is oriented along both the x- and y-axes of the spatial coordinate system. Furthermore, in low-pressure and low-temperature plasmas, the collision frequency is much lower than the angular frequency of the terahertz wave, so the plasma can be considered a collisionless medium.

[0059] When the plasma is in a low temperature state, the electric field distribution is determined by the following formula:

[0060]

[0061] Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

[0062] In this embodiment, in high-temperature plasma, the collision frequency of the plasma is close to the angular frequency of the terahertz wave, and the plasma is considered as a collision medium. Therefore, when calculating the electric field distribution, the effect of the plasma collision frequency on the electric field distribution is taken into account.

[0063] When the plasma is at a high temperature, the electric field distribution is determined by the following formula:

[0064]

[0065] Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

[0066] like Figure 4 As shown in the figure, in an embodiment of the present invention, when the plasma-encapsulated target is a copper body, the terahertz wave scattered electric field distribution calculated using the above method shows a certain pattern, with the electric field intensity increasing from blue to red. It is worth noting that there is no electric field in the target body area enclosed by the plasma region.

[0067] In one embodiment of the present invention, the above steps regard plasma as an equivalent dielectric whose conductivity is zero.

[0068] Regarding step 108:

[0069] In one embodiment of the present invention, the terahertz wave is introduced into the plasma-encased target body, using the free space facing the terahertz irradiation surface as a plane wave. The electric field scattered in all directions is compared with the electric field in the incoming wave direction to determine the omnidirectional terahertz wave scattering pattern of the plasma-encased target, thereby determining the terahertz wave scattering characteristics of the plasma-encased target.

[0070] like Figure 5As shown in the figure, in this embodiment of the present invention, the dark blue curve represents the radiation direction of a 0.1THz terahertz wave around a plasma-covered target, the green curve is the corresponding radiation direction of a 0.2THz terahertz wave, the red curve indicates the radiation direction of a 0.3THz terahertz wave around a plasma-covered target, the light blue curve shows the situation of a 0.4THz terahertz wave, the purple curve reflects the radiation direction of a 0.5THz terahertz wave around a target, the orange curve indicates the radiation direction of a 1THz terahertz wave around a plasma-covered target, and the black curve also indicates the radiation direction of a 2THz terahertz wave around a plasma-covered target. Here, the curves of different colors clearly outline the unique radiation directions of terahertz waves of different frequencies around a plasma-covered target, which is of vital importance for in-depth exploration of the interaction between terahertz waves and plasma-covered targets.

[0071] like Figure 6 、 Figure 7 As shown, an embodiment of the present invention provides a device for simulating the terahertz wave scattering characteristics of a plasma-coated target. The device embodiment can be implemented by software, hardware, or a combination of software and hardware. From the hardware level, Figure 6 As shown in FIG. 1 , a hardware architecture diagram of an electronic device in which a device for simulating the terahertz wave scattering characteristics of a plasma-coated target provided by an embodiment of the present invention is located, except for Figure 6 In addition to the processor, memory, network interface, and non-volatile memory shown, the electronic device in the embodiment may also include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 7 As shown, as a device in a logical sense, it is formed by the CPU of the electronic device in which it is located reading the corresponding computer program in the non-volatile memory into the internal memory and running it.

[0072] like Figure 7 As shown, this embodiment provides a device for simulating terahertz wave scattering characteristics of a plasma-coated target, the device comprising:

[0073] An acquisition module 700 is used to acquire geometric parameters of the plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma;

[0074] a first model building module 702 for determining a two-dimensional model of the plasma-coated target based on the geometric parameters, and assigning corresponding material properties to the two-dimensional model to obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, wherein the plasma region encloses the target body region, and the free space region encloses the plasma region;

[0075] A second model building module 704 is used to bring the characteristic parameters into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target;

[0076] A first data processing module 706 is configured to perform finite element simulation calculations using the simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric fields scattered in all directions;

[0077] The second data processing module 708 is used to compare the electric field scattered in all directions with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

[0078] In an embodiment of the present invention, the acquisition module 700 can be used to execute step 100 in the above method embodiment, the first model building module 702 can be used to execute step 102 in the above method embodiment, the second model building module 704 can be used to execute step 104 in the above method embodiment, the first data processing module 706 can be used to execute step 106 in the above method embodiment, and the second data processing module 708 can be used to execute step 108 in the above method embodiment.

[0079] In one embodiment of the present invention, the terahertz wave electric field distribution of the plasma-coated blunt body is obtained by performing simulation calculation using a simulation model of the plasma-coated blunt body terahertz wave scattering characteristics, including:

[0080] Determining the equivalent dielectric constant of the plasma based on the characteristic parameter;

[0081] Solving Maxwell's equations based on the equivalent dielectric constant;

[0082] Based on the Maxwell equations, the electric field distribution is determined.

[0083] In one embodiment of the present invention, the equivalent dielectric constant is determined by the following formula:

[0084]

[0085] Where, ε p is the equivalent dielectric constant, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma; n e is the electron density; e is the electron charge; m e The mass of the electron.

[0086] In one embodiment of the present invention, the Maxwell equations are:

[0087]

[0088] Where, ε p is the equivalent dielectric constant, j is the imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field strength vector, is the electric field strength vector.

[0089] In one embodiment of the present invention, when the terahertz wave is transmitted in the low-temperature plasma, the electric field distribution is determined by the following formula:

[0090]

[0091] Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

[0092] In one embodiment of the present invention, when the terahertz wave is transmitted in a high-temperature plasma, the electric field distribution is determined by the following formula:

[0093]

[0094] Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

[0095] In one embodiment of the present invention, the conductivity of the plasma is 0.

[0096] It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on a device for simulating the terahertz wave scattering characteristics of a plasma-encapsulated target. In other embodiments of the present invention, a device for simulating the terahertz wave scattering characteristics of a plasma-encapsulated target may include more or fewer components than illustrated, or may combine or separate certain components, or employ a different component arrangement. The illustrated components may be implemented in hardware, software, or a combination of both.

[0097] The information interaction, execution process, etc. between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For specific contents, please refer to the description in the embodiment of the method of the present invention and will not be repeated here.

[0098] An embodiment of the present invention further provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a method for simulating terahertz wave scattering characteristics of a plasma-coated target according to any embodiment of the present invention is implemented.

[0099] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes a method for simulating terahertz wave scattering characteristics of a plasma-coated target according to any embodiment of the present invention.

[0100] Specifically, a system or device equipped with a storage medium can be provided, on which software program codes that implement the functions of any of the above-mentioned embodiments are stored, and a computer (or CPU or MPU) of the system or device can be enabled to read and execute the program codes stored in the storage medium.

[0101] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute part of the present invention.

[0102] Examples of storage media for providing program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Alternatively, the program code can be downloaded from a server computer via a communication network.

[0103] In addition, it should be clear that the functions of any of the above embodiments can be achieved not only by executing the program code read by the computer, but also by enabling the operating system operating on the computer to complete part or all of the actual operations based on the instructions of the program code.

[0104] In addition, it can be understood that the program code read from the storage medium is written into the memory provided in the expansion board inserted into the computer or into the memory provided in the expansion module connected to the computer, and then based on the instructions of the program code, the CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above embodiments.

[0105] It should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0106] Those skilled in the art will understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk, etc. Various media that can store program codes.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for simulating the terahertz wave scattering characteristics of a plasma-coated target, characterized in that: include: Acquiring geometric parameters of the plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma; Based on the geometric parameters, a two-dimensional model of the plasma-coated target is determined, and corresponding material properties are assigned to the two-dimensional model to obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, the plasma region enveloping the target body region, and the free space region enveloping the plasma region; Bringing the characteristic parameters into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target; Finite element simulation calculations are performed using the simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric fields scattered in all directions; The electric fields scattered in all directions are compared with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

2. The method according to claim 1, characterized in that The method of performing simulation calculations using the simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target includes: Determining the equivalent dielectric constant of the plasma based on the characteristic parameter; Solving Maxwell's equations based on the equivalent dielectric constant; Based on the Maxwell equations, the electric field distribution of the scattered terahertz wave is determined.

3. The method according to claim 2, characterized in that The equivalent dielectric constant is determined by the following formula: Where, ε p is the equivalent dielectric constant, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma; n e is the electron density; e is the electron charge; m e The mass of the electron.

4. The method according to claim 2, characterized in that The Maxwell equations are: Where, ε p is the equivalent dielectric constant, j is the imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field strength vector, is the electric field strength vector.

5. The method according to claim 2, characterized in that When a terahertz wave is transmitted in a low-temperature plasma, the electric field distribution of the terahertz wave is determined by the following formula: Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

6. The method according to claim 2, characterized in that When the terahertz wave propagates in high-temperature plasma, the electric field distribution is determined by the following formula: Where μ r is the relative magnetic permeability of the plasma, ε r is the relative dielectric constant, ε0 is the vacuum dielectric constant, ν is the collision frequency, ω is the angular frequency of the terahertz wave, j is the imaginary operator, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

7. The method according to any one of claims 4 to 6, characterized in that The conductivity of the plasma is zero.

8. A device for simulating the terahertz wave scattering characteristics of a plasma-coated target, characterized in that: include: An acquisition module, configured to acquire geometric parameters of a plasma-encapsulated target and characteristic parameters of the plasma; wherein the characteristic parameters include the electron density and collision frequency of the plasma; a first model building module, configured to determine a two-dimensional model of the plasma-coated target based on the geometric parameters, and assign corresponding material properties to the two-dimensional model to obtain a physical model; wherein the physical model includes a plasma region, a free space region, and a target body region, wherein the plasma region encloses the target body region, and the free space region encloses the plasma region; A second model building module is used to bring the characteristic parameters of the plasma into the plasma region to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target; A first data processing module is configured to perform finite element simulation calculations using a simulation model of the terahertz wave scattering characteristics of the plasma-encapsulated blunt body target to obtain an electric field distribution of the terahertz wave scattered by the plasma-encapsulated blunt body target; wherein the electric field distribution of the terahertz wave includes an electric field in an incoming wave direction and electric fields scattered in all directions; The second data processing module is used to compare the electric field of the terahertz wave scattered in all directions with the electric field in the incoming wave direction to determine the terahertz wave scattering pattern of the plasma-coated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-coated target.

9. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed in a computer, the computer is caused to execute the method according to any one of claims 1 to 7.

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