Simulation method and device for terahertz wave scattering characteristic of plasma coated target

Abstract

The invention relates to the field of optics, in particular to a method and a device for simulating terahertz wave scattering characteristics of a plasma coated target. According to the method, a two-dimensional model is constructed through geometric parameters of a plasma region and a coating target of the plasma region, and corresponding material attributes are endowed to the two-dimensional model, so that a physical model is obtained. Characteristic parameters of the plasma are introduced into a plasma area of the physical model, and then a simulation model of the terahertz wave scattering characteristics of the plasma-coated target is obtained. Finite element analogue simulation calculation is carried out by utilizing the simulation model, so that the electric field distribution of the plasma coated target is obtained. And comparing the electric field scattered to each direction by the target with the electric field in the incoming wave direction to determine the complete terahertz wave scattering characteristic of the plasma coated target. According to the invention, researchers can be helped to quickly understand the terahertz wave scattering characteristics of the plasma coated target.

Description

Technical Field

[0001] The present invention relates to the field of optics, and in particular to a method and a 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 the related art, the terahertz wave scattering measurement system is often complex and has a small dynamic range, which leads to inaccurate simulation results of the terahertz wave scattering characteristics of plasma-coated targets.

[0004] Based on this, a simulation method and device for terahertz wave scattering characteristics of a plasma-coated target are urgently needed 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 device 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 envelops the target body region, and the free space region envelops 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 calculation is performed using the simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-coated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric field scattered in all directions;

[0011] The electric field scattered in all directions is compared with the electric field in the incoming wave direction to determine the terahertz wave scattering direction diagram 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, 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;

[0014] A first model building module is used 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, the plasma region envelops the target body region, and the free space region envelops 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-coated blunt body target;

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

[0017] The second data processing module is used to compare the electric field scattered in various 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, including 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] The embodiment of the present invention provides a method and device for simulating the terahertz wave scattering characteristics of a plasma-coated target. First, a two-dimensional model is constructed according to the geometric parameters of the plasma-coated target, and the corresponding material properties are assigned to the two-dimensional model to obtain a physical model. Subsequently, the 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, and this model can be used to simulate the transmission condition of the terahertz wave of the plasma-coated target. Next, the simulation model of the terahertz wave scattering characteristics of the plasma-coated target is used to carry out simulation calculations 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 all directions. In this way, the problems of complexity and small dynamic range of the existing terahertz transmission measurement system are overcome, and the technical problem of how to quickly grasp the terahertz wave scattering characteristics of the plasma-coated target is solved. 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 drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0022] Figure 1 It 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 It is a schematic diagram of the scattered electric field distribution of a terahertz wave by a plasma-coated copper bluff body provided by an embodiment of the present invention;

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

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

[0028] Figure 7It is a structural diagram of a simulation device for 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, rather than all the embodiments. Based on the embodiments in 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 The 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: obtaining 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;

[0032] Step 102: Based on the geometric parameters, determine a two-dimensional model of the plasma-coated target, 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, the plasma region envelops the target body region, and the free space region envelops the plasma region;

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

[0034] Step 106: performing finite element simulation calculation using a simulation model of terahertz wave scattering characteristics of a 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 an electric field in an incoming wave direction and electric fields scattered in all directions;

[0035] Step 108: 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.

[0036] In an embodiment of the present invention, first, a two-dimensional model is constructed according to the geometric parameters of the plasma-coated target, and the corresponding material properties are assigned to the two-dimensional model to obtain a physical model. Subsequently, the 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, and this model can be used to simulate the transmission condition of the terahertz wave of the plasma-coated target. Next, the simulation model of the terahertz wave scattering characteristics of the plasma-coated target is used to carry out simulation calculations 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 all directions. In this way, the problems of complexity and small dynamic range of the current terahertz wave transmission measurement system are overcome, and the technical problem of how to improve the speed of solving the terahertz wave scattering characteristics of the plasma-coated target is solved.

[0037] Described below Figure 1 How the various steps are performed.

[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 camera (ICCD). The fiber collection direction, the laser direction, and the plasma beam axis are all at a right angle of 90 degrees. A group of convex lens combinations set at the front end of the optical fiber can accurately focus the area where the laser and plasma interact at the fiber entrance. Subsequently, the Thomson scattering signal collected by the optical fiber will be transmitted to the TGS system. In the TGS system, it will be processed by a series of optical devices such as gratings and lenses, and finally imaged (spectrified) on the ICCD camera. In order 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 optical fiber and the collection lens are placed in a dark room. By carrying out laser Thomson scattering measurement on the plasma, the distribution of the characteristic parameters of the plasma can be directly obtained.

[0040] In one embodiment of the present invention, the electron density of the plasma can be measured by means of a Langmuir probe. The specific operation method is: inserting a very small electrode into the plasma, and then applying a specific voltage to it, and then measuring the relationship between the current passing through the electrode and the applied voltage. Through in-depth analysis of special points on the voltage-current characteristic curve, the electron density of the plasma can be calculated.

[0041] In one embodiment of the present invention, the geometric parameters of the plasma-coated target can be collected using a laser scanning device. First, it is necessary to ensure that the laser beam can completely cover all areas on the plasma-coated target that need to be measured. Then, the scanning program is started and the reflected light signal is recorded at the same time. In the data processing stage, the coordinates of each point on the surface of the plasma-coated target are calculated based on the relevant parameters such as the angle and time of the laser scanning, and combined with the optical property model of the plasma. In this way, the geometric parameters of the plasma-coated target, such as length, width, and flatness, can be obtained.

[0042] Regarding step 102:

[0043] In one embodiment of the present invention, appropriate two-dimensional 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 two-dimensional model file is created in the software, and the unit system of the model is properly set to ensure that it matches the unit of the geometric parameters. Subsequently, the corresponding material properties are assigned to the two-dimensional model to obtain a physical model. Those skilled in the art can customize the material properties according to 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 FIG. 1 , in one embodiment of the present invention, the plasma region encloses the target body region, the free space region encloses the plasma region (blue region), and the left side of the free space region is the entrance of the terahertz wave. The terahertz wave is incident from the free space region and irradiates the target covered by the plasma, and the wave is scattered after interacting with the plasma and the target body.

[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 zone, and the characteristic parameters are enhanced from blue to red. The characteristic parameters are brought into the plasma zone to obtain a simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body target, which is used to simulate the terahertz wave transmission of the plasma-coated blunt body target. By defining variables, the plasma electron density (the collision frequency is sometimes a certain value, and sometimes a distribution data) obtained by external measurement or simulation is imported into the blue plasma area in the model in the form of an interpolation function. In addition to the plasma zone, the corresponding part materials in the model are selected and set for the free space zone and the target body zone. 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] In the formula, 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 operator of the imaginary number, 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] In the formula, ε p is the equivalent dielectric constant, j is an imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field intensity vector, is the electric field strength vector.

[0058] In this embodiment, the terahertz electromagnetic wave propagating in the plasma propagates along the z-axis of the spatial coordinate axis, and the electric field direction is along the x-axis and y-axis of the spatial coordinate axis. In addition, in a plasma under low pressure and low temperature conditions, the collision frequency of the plasma is much smaller than the angular frequency of the terahertz wave, so the plasma can be regarded as a collision-free medium.

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

[0060]

[0061] In the formula, 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 operator of the imaginary number, ω pe is the angular frequency of the plasma, σ is the conductivity, is the electric field vector.

[0062] In this embodiment, in a plasma under high temperature conditions, 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 influence of the collision frequency of the plasma on the electric field distribution is considered.

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

[0064]

[0065] In the formula, 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 the embodiment of the present invention, when the plasma-encapsulated target is a copper bluff body, the terahertz wave scattered electric field distribution calculated by the above method shows a certain regularity, and the electric field intensity increases from blue to red. It is worth noting that there is no electric field in the target body area encapsulated by the plasma area.

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

[0068] Regarding step 108:

[0069] In one embodiment of the present invention, the side of the free space facing the terahertz irradiation surface of the plasma-encapsulated target is used as the entrance of the terahertz wave, and the terahertz wave irradiates the target body encapsulated by the plasma as a plane wave. The electric field scattered in all directions is compared with the electric field in the direction of the incoming wave to determine the terahertz wave scattering direction diagram of the plasma-encapsulated target in all directions, thereby determining the terahertz wave scattering characteristics of the plasma-encapsulated target.

[0070] like Figure 5As shown, in the embodiment of the present invention, the dark blue curve represents the radiation direction of the terahertz wave with a frequency of 0.1THz around the plasma coverage target, the green curve is the corresponding radiation direction of the terahertz wave with a frequency of 0.2THz, the red curve indicates the radiation direction of the terahertz wave with a frequency of 0.3THz around the plasma coverage target, the light blue curve shows the situation of the terahertz wave with a frequency of 0.4THz, the purple curve reflects the radiation direction of the terahertz wave with a frequency of 0.5THz around the target, the orange curve represents the radiation direction of the terahertz wave with a frequency of 1THz around the plasma coverage target, and the black curve also represents the radiation direction of the terahertz wave with a frequency of 2THz around the plasma coverage target. Here, curves of different colors clearly outline the unique radiation directions of terahertz waves of different frequencies when they surround the plasma coverage target, which is of vital importance for in-depth exploration of the interaction between terahertz waves and plasma coverage 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, or by hardware or a combination of software and hardware. From the hardware level, Figure 6 As shown, it is a hardware architecture diagram of an electronic device in which a simulation device for terahertz wave scattering characteristics of a plasma-coated target provided by an embodiment of the present invention is located. 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, the CPU of the electronic device in which it is located reads the corresponding computer program in the non-volatile memory into the internal memory and runs 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 a 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 is used 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, the plasma region envelops the target body region, and the free space region envelops 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-coated blunt body target;

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

[0077] The second data processing module 708 is used to compare the electric field scattered in various 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 simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body is used to perform simulation calculations to obtain the terahertz wave electric field distribution of the plasma-coated blunt body, including:

[0080] Based on the characteristic parameters, determining the equivalent dielectric constant of the plasma;

[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] In the formula, 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] In the formula, ε p is the equivalent dielectric constant, j is an imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field intensity 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] In the formula, 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 operator of the imaginary number, 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] In the formula, 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 zero.

[0096] It is understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a device for simulating terahertz wave scattering characteristics of a plasma-encapsulated target. In other embodiments of the present invention, a device for simulating terahertz wave scattering characteristics of a plasma-encapsulated target may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0097] The information interaction, execution process and other contents 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 the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0098] An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a simulation method for terahertz wave scattering characteristics of a plasma-coated target in 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 in 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 a part of the present invention.

[0102] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

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

[0104] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a 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-mentioned embodiments.

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

[0106] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments 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 method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic 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 embodiments of the present invention.

Claims

1. A method for simulating 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 envelops the target body region, and the free space region envelops 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 calculation is performed using the simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-coated blunt body target; wherein the electric field distribution includes the electric field in the incoming wave direction and the electric field scattered in all directions; The electric field scattered in all directions is compared with the electric field in the incoming wave direction to determine the terahertz wave scattering direction diagram 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 using the simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body target to perform simulation calculations to obtain the electric field distribution of the terahertz wave scattered by the plasma-coated blunt body target includes: Based on the characteristic parameters, determining the equivalent dielectric constant of the plasma; 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: In the formula, 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: In the formula, ε p is the equivalent dielectric constant, j is an imaginary operator, ω is the angular frequency of the terahertz wave, is the magnetic field intensity vector, is the electric field strength vector.

5. The method according to claim 2, characterized in that: When the terahertz wave is transmitted in the low-temperature plasma, the electric field distribution of the terahertz wave is determined by the following formula: In the formula, 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 operator of the imaginary number, 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 is transmitted in high-temperature plasma, the electric field distribution is determined by the following formula: In the formula, 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 terahertz wave scattering characteristics of a plasma-coated target, characterized in that: include: An acquisition module, 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; A first model building module is used 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, the plasma region envelops the target body region, and the free space region envelops 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-coated blunt body target; A first data processing module is used to perform finite element simulation calculation using the simulation model of the terahertz wave scattering characteristics of the plasma-coated blunt body target to obtain the electric field distribution of the terahertz wave scattered by the plasma-coated blunt body target; wherein the electric field distribution of the terahertz wave includes the electric field in the incoming wave direction and the electric field scattered in all directions; The second data processing module is used to compare the terahertz wave 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.

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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