Electromagnetic signal analogue simulation method and device in complex multi-region natural environment

Abstract

The invention provides an electromagnetic signal simulation method and device in a complex multi-region natural environment. The method comprises the steps of obtaining characteristic parameters of a complex multi-region natural environment, performing spatial discretization and numerical calculation by using a DGTD method and a PE method, obtaining electromagnetic disturbance propagation characteristic data of each region, obtaining transfer functions of different regions by using discrete Laplacian transformation, cascading the transfer functions of the regions, and obtaining electromagnetic disturbance propagation characteristic data of the regions; obtaining a transfer function of the whole electromagnetic disturbance propagation area; and mixing the original electromagnetic signals and the characteristic parameters of the whole electromagnetic disturbance propagation area by using a LABVIEW program to obtain output signals, and carrying out analogue simulation processing on the output signals by using NI and a radiation type semi-physical simulation device to obtain analogue simulation electromagnetic signals of the complex multi-area natural environment. The electromagnetic signal simulation in the complex natural environment can accurately simulate the real electromagnetic environment of an external field, and the problem that indoor simulation equivalently replaces the external field test of environments with complex structure obstacles and the like is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic signal simulation, and in particular to a method and device for simulating electromagnetic signals in a complex multi-region natural environment. Background Art

[0002] With the continuous development of electronic information technology, more and more electrical and electronic equipment are widely used in complex systems such as aircraft, ships and rail transit trains. At present, the common means of studying the electromagnetic effects and anti-interference performance of equipment mainly include full digital simulation and field tests. Full digital simulation technology has the advantages of all-weather, multi-scenario and low cost. However, full digital simulation technology cannot reflect the complex characteristics of systems outside mathematical models, especially for problems such as internal circuit coupling and multi-physical field effects of equipment. It is difficult to accurately simulate. In addition, it is not possible to fully complete the integration verification of electrical systems. For field tests, although the real scene can be restored to the maximum extent, the test costs such as manpower and material resources are high. In addition, it is difficult to switch the scene at any time in field tests, resulting in low flexibility. In comparison, semi-physical simulation technology, with its combination of "virtual" and "physical", can not only retain the flexibility in full digital simulation, but also integrate the real reliability of physical hardware in field tests.

[0003] However, usually in the test environment, the interference signal is simulated and output by the signal generator, and such signals often ignore the impact of the environment on the signal. For example, environmental factors such as the atmospheric medium environment, terrain, soil, and complex structural obstacles in the propagation path may affect the propagation of electromagnetic interference. These impacts on the prediction of interference signals are real, and also put forward higher requirements for the simulation of semi-physical simulation. How to use digital simulation to fully and accurately simulate the real electromagnetic environment of the field is of great significance for equivalent replacement of field tests.

[0004] Therefore, there is an urgent need for a method to simulate electromagnetic signals in complex natural environments. Summary of the invention

[0005] The embodiments of the present invention provide a method and device for simulating electromagnetic signals in a complex multi-region natural environment, so as to effectively utilize indoor simulation to replace outdoor tests in environments with complex structural obstacles.

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

[0007] According to one aspect of the present invention, a method for simulating electromagnetic signals in a complex multi-region natural environment is provided, comprising:

[0008] Obtain the characteristic parameters of terrain, landform and meteorological conditions of complex multi-regional natural environment, and use the time domain discontinuous Galerkin-parabolic DGTD method and parabolic equation PE method to perform spatial discretization and numerical calculation based on the characteristic parameters to obtain electromagnetic disturbance propagation characteristic data of each region;

[0009] According to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each area, the transfer function of different areas is obtained by using discrete Laplace transform, and the transfer function of each area is cascaded to obtain the transfer function of the entire electromagnetic disturbance propagation area;

[0010] According to the transfer function of the entire electromagnetic disturbance propagation area, the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area are mixed using the LABVIEW program to obtain an output signal, and the output signal is simulated by using a virtual instrument NI and a radiation semi-physical simulation device to obtain a simulated electromagnetic signal of the complex multi-region natural environment.

[0011] Preferably, the method of obtaining characteristic parameters of terrain, landform and meteorological conditions of a complex multi-region natural environment, and performing spatial discretization and numerical calculation using a DGTD method and a PE method according to the characteristic parameters to obtain electromagnetic disturbance propagation characteristic data of each region includes:

[0012] Obtain the characteristic parameters of terrain, geomorphology and meteorological conditions of complex multi-regional natural environments, and use the DGTD method and PE method to perform spatial discretization and numerical calculation based on the various characteristic parameters obtained;

[0013] For flat terrain, the step-by-step Fourier transform SSFT-PE method is used to calculate the propagation process of electromagnetic waves and predict the electromagnetic disturbance propagation characteristics in flat terrain space.

[0014] For complex terrain and rough surface, the alternating direction implicit ADI-PE method is used to calculate the electromagnetic disturbance propagation characteristics;

[0015] Calculate the time domain signal near the obstacle as the output signal of the TDPE area. If there is mutual coupling between obstacles, use the DGTD method to solve the backscattering of the obstacle.

[0016] Output electromagnetic disturbance propagation characteristic data of each area, the electromagnetic disturbance propagation characteristic data including the frequency, intensity, waveform, propagation path and phase information of the interference signal, and the time domain signal near the obstacle. Preferably, the transfer function of different areas is obtained by discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data of each area, the input electromagnetic signal and the output electromagnetic signal, and the transfer function of each area is cascaded to obtain the transfer function of the entire electromagnetic disturbance propagation area, including:

[0017] Assume that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source:

[0018]

[0019] Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c is the center frequency

[0020] The TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved, and this time domain signal is used as the output signal y of the TDPE area. PE (t), taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle DG (t), based on the input and output signals of each area, the transfer functions of different areas are obtained by discrete Laplace transform, and the transfer functions of different areas are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area;

[0021] The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is:

[0022] y(t)=x(t)*h(t) (2)

[0023] The transfer function of the TDPE region is expressed as:

[0024]

[0025] Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation.

[0026] Assuming that the distance between obstacles is far enough to ignore the multiple scattering between them, T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively:

[0027]

[0028] T DG (z) is the transfer function of the DGTD region, x(z) and y DG (z) are the input and output discrete time domain signals x(k) and y of the DGTD region, respectively. DG (k) The result after Z transformation;

[0029] If there is mutual coupling between obstacles, the DGTD method is used to solve the backscattering of the obstacles.

[0030] Preferably, the method of mixing the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area using a LABVIEW program according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, and using a NI virtual instrument and a radiation-type semi-physical simulation device to simulate the output signal to obtain a simulated electromagnetic signal of the complex multi-region natural environment includes:

[0031] According to the transfer function of the entire electromagnetic disturbance propagation area, the original electromagnetic signal of the entire electromagnetic disturbance propagation area and the characteristic parameters of the complex natural environment are mixed using the LABVIEW program to obtain an output signal, and the output signal is simulated data processed by the NI virtual instrument to output a simulated electromagnetic signal;

[0032] The simulated electromagnetic signal is processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to implement a radiation-type electromagnetic effect semi-physical simulation process, thereby obtaining the simulated electromagnetic signal of the complex multi-region natural environment.

[0033] According to another aspect of the present invention, there is provided an electromagnetic signal simulation device in a complex multi-region natural environment, comprising: a first calculation module, a second calculation module and a third calculation module;

[0034] The first calculation module obtains the characteristic parameters of the terrain, landform and meteorological conditions of the complex multi-region natural environment, and uses the time domain discontinuous Galerkin-parabolic DGTD method and the parabolic equation PE method to perform spatial discretization and numerical calculation according to the characteristic parameters to obtain the electromagnetic disturbance propagation characteristic data of each region;

[0035] The second calculation module obtains the transfer functions of different regions by using discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each region, and cascades the transfer functions of each region to obtain the transfer function of the entire electromagnetic disturbance propagation region;

[0036] The third calculation module uses the LABVIEW program to mix the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, and uses NI virtual instruments and radiation semi-physical simulation devices to simulate the output signal to obtain the simulated electromagnetic signal of the complex multi-region natural environment.

[0037] Preferably, the first calculation module is specifically used to obtain characteristic parameters of terrain, landform and meteorological conditions of a complex multi-region natural environment, and perform spatial discretization and numerical calculation using the DGTD method and the PE method according to the various characteristic parameters obtained;

[0038] For flat terrain, the step-by-step Fourier transform SSFT-PE method is used to calculate the propagation process of electromagnetic waves and predict the electromagnetic disturbance propagation characteristics in flat terrain space.

[0039] For complex terrain and rough surface, the alternating direction implicit ADI-PE method is used to calculate the electromagnetic disturbance propagation characteristics;

[0040] Calculate the time domain signal near the obstacle as the output signal of the TDPE area. If there is mutual coupling between obstacles, use the DGTD method to solve the backscattering of the obstacle.

[0041] Output electromagnetic disturbance propagation characteristic data of each area, the electromagnetic disturbance propagation characteristic data including the frequency, intensity, waveform, propagation path and phase information of the interference signal, and the time domain signal near the obstacle. Preferably, the second calculation module is specifically used to obtain the transfer function of different areas by discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data of each area, the input electromagnetic signal and the output electromagnetic signal, cascade the transfer function of each area, and obtain the transfer function of the entire electromagnetic disturbance propagation area, including:

[0042] Assume that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source:

[0043]

[0044] Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c is the center frequency

[0045] The TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved, and this time domain signal is used as the output signal y of the TDPE area. PE (t), taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle DG (t), based on the input and output signals of each area, the transfer functions of different areas are obtained by discrete Laplace transform, and the transfer functions of different areas are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area;

[0046] The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is:

[0047] y(t)=x(t)*h(t) (2)

[0048] The transfer function of the TDPE region is expressed as:

[0049]

[0050] Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation.

[0051] Assuming that the distance between obstacles is far enough to ignore the multiple scattering between them, T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively:

[0052]

[0053] T DG (z) is the transfer function of the DGTD region, x(z) and y DG (z) are the input and output discrete time domain signals x(k) and y of the DGTD region, respectively. DG (k) The result after Z transformation;

[0054] If there is mutual coupling between obstacles, the DGTD method is used to solve the backscattering of the obstacles.

[0055] Preferably, the third calculation module is specifically used to mix the original electromagnetic signal of the entire electromagnetic disturbance propagation area and the characteristic parameters of the complex natural environment using the LABVIEW program according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, perform analog data processing on the output signal through the NI virtual instrument, and output a simulated electromagnetic signal;

[0056] The simulated electromagnetic signal is processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to implement a radiation-type electromagnetic effect semi-physical simulation process, thereby obtaining the simulated electromagnetic signal of the complex multi-region natural environment.

[0057] According to another aspect of the present invention, there is provided a computer device, comprising:

[0058] A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the electromagnetic signal simulation method in a complex multi-region natural environment as described in any one of claims 1 to 4 by executing the computer instructions.

[0059] According to another aspect of the present invention, a computer-readable storage medium is provided, on which computer instructions are stored, and the computer instructions are used to enable a computer to execute the electromagnetic signal simulation method in a complex multi-region natural environment as described in any one of claims 1 to 4.

[0060] It can be seen from the technical solutions provided by the above-mentioned embodiments of the present invention that the electromagnetic signal simulation under complex natural environments ultimately established by the present invention can accurately simulate the real electromagnetic environment of the external field, solving the problem of indoor simulation equivalently replacing external field tests in environments with complex structural obstacles.

[0061] Additional aspects and advantages of the present invention will be given in part in the following description, which will become obvious from the following description, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0063] Figure 1 It is a flowchart of a method for simulating electromagnetic signals in a complex natural environment according to an embodiment of the present invention;

[0064] Figure 2 is a flow chart of another method for simulating electromagnetic signals in a complex natural environment according to an embodiment of the present invention;

[0065] Figure 3 is a flow chart of another method for simulating electromagnetic signals in a complex natural environment according to an embodiment of the present invention;

[0066] Figure 4 is a schematic diagram of a method for constructing an electromagnetic signal propagation area transfer function based on discrete Laplace transform according to an embodiment of the present invention;

[0067] Figure 5 is a schematic diagram of regional transfer function extraction according to an embodiment of the present invention;

[0068] Figure 6 is a schematic diagram of a method for simulating electromagnetic signals under a complex natural environment according to an embodiment of the present invention;

[0069] Figure 7 is a schematic diagram of a multi-region segmentation surface according to an embodiment of the present invention;

[0070] Figure 8is a structural diagram of an electromagnetic signal simulation device in a complex multi-region natural environment according to an embodiment of the present invention;

[0071] Fig. 9 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0072] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0073] It will be understood by those skilled in the art that, unless expressly stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or coupling. The term "and / or" used herein includes any unit and all combinations of one or more associated listed items.

[0074] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0075] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each embodiment does not constitute a limitation on the embodiments of the present invention.

[0076] Researching and analyzing the impact of environmental factors such as the atmospheric medium environment, terrain, soil, and complex structural obstacles in the propagation path on the propagation of electromagnetic interference is one of the keys to solving the problem of equivalent replacement of field tests. Therefore, the present invention provides an electromagnetic signal simulation method in a complex natural environment, which can solve the problem of indoor simulation equivalent replacement of field tests in environments such as complex structural obstacles.

[0077] In this embodiment, a simulation method for electromagnetic environment effects under different environments is provided, which can be used in servers, such as desktop computers, tablet computers, etc. The flowchart of a simulation method for electromagnetic signals under complex natural environments provided by an embodiment of the present invention is as follows: Figure 1 As shown, the process includes the following steps:

[0078] Step S101, predicting electromagnetic disturbance propagation characteristics in a complex multi-region natural environment based on the DGTD (Discontinuous Galerkin Time Domain) equation.

[0079] The characteristic parameters of the topography, landform and meteorological conditions of the complex multi-regional natural environment are obtained, and the DGTD method and PE (Parabolic Equation) method (including SSFT (Spit-step Fourier Transform)-PE and ADI (Alternating Direction Implicit)-PE) are used for spatial discretization and numerical calculation according to the various characteristic parameters obtained.

[0080] For flat terrain, the SSFT-PE method is used to calculate the propagation process of electromagnetic waves.

[0081] For complex terrain and rough surface, the ADI-PE method is used to improve the numerical accuracy.

[0082] The time domain signal near the obstacle is calculated as the output signal of the TDPE area. If there is mutual coupling between obstacles, the backscattering of the obstacle is solved using the DGTD method.

[0083] Finally, the electromagnetic disturbance propagation characteristic data of each area is output, and the electromagnetic disturbance propagation characteristic data includes information such as the frequency, intensity, waveform, propagation path and phase of the interference signal, as well as the time domain signal near the obstacle, etc. It serves as the input for the subsequent steps. Step S102: construct an electromagnetic signal propagation area transfer function based on discrete Laplace transform.

[0084] According to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each area, discrete Laplace transform is used to obtain the transfer function of different areas, and the transfer function of each area is cascaded to obtain the transfer function of the entire electromagnetic disturbance propagation area.

[0085] If necessary, the system identification module in the Matlab simulation software is used to quickly solve the system transfer function coefficients.

[0086] Step S103, a method and device for simulating electromagnetic signals in a complex natural environment based on NI (National Instruments, virtual instrument).

[0087] According to the transfer function of the entire electromagnetic disturbance propagation area, the LABVIEW program is used to mix the original electromagnetic signal of the entire electromagnetic disturbance propagation area (such as a sinusoidally modulated Gaussian pulse signal) and the characteristic parameters of the complex natural environment to obtain the output signal. The above output signal is simulated data processed by the NI virtual instrument to output the simulated electromagnetic signal.

[0088] The simulated electromagnetic signals are processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to realize a radiation-type electromagnetic effect semi-physical simulation process, so as to obtain the simulated electromagnetic signals of the complex multi-region natural environment.

[0089] Figure 2 Yes Figure 1 Detailed step-by-step introduction of step S101 and step S102, Figure 3 Yes Figure 1 Detailed implementation steps of step S103.

[0090] Specifically, step S101 includes that DGTD is a time domain numerical calculation method of the same type as the time domain finite element (FETD). The spatial discretization of the DGTD method has the same characteristics as the FETD method. Both methods use unstructured grids to realize the spatial discretization of the calculation area. The unstructured grid has the advantage of better fitting effect on curved surfaces and complex structures, and can avoid the problem of approximate error when using orthogonal grids in the FDTD method. Another feature of the DGTD method is that it quotes the numerical flux in the time domain finite volume method. This method can relax the constraints on the tangential continuity of the electromagnetic field, which is conducive to realizing regional decomposition and parallel calculation. At the same time, compared with the problem of huge global system matrix dimension in the traditional FETD method, the DGTD method is much less than the calculation amount of FETD in the inversion of the unit matrix, and the processing of the step-by-step solution between adjacent units in the time domain has similar characteristics to the finite difference time domain (FDTD). DGTD is based on Maxwell's curl equation, while FETD is based on the discrete electromagnetic field wave equation. Therefore, the DGTD explicit electromagnetic field alternating stepping scheme and the FETD method require less computational effort to solve the global system matrix in each step. In short, the DGTD method combines the advantages of both FETD and FDTD, while avoiding the disadvantages of both methods, and has become a cutting-edge method for calculating multi-scale, dispersive media and other scattering problems.

[0091] The PE method is obtained by approximating the Maxwell wave equation. Compared with the high-frequency approximation algorithm, the parabolic equation method fully considers the influence of electromagnetic wave refraction and diffraction, and at the same time processes the refractive index term in view of environmental effects such as complex geographical environment and meteorological environment. Compared with the full-wave numerical method, the biggest advantage of the Spit-step Fourier Transform (SSFT) solution in the parabolic equation is that the electromagnetic wave wavelength has little effect on the iterative step length, which makes the algorithm more efficient and consumes less memory. Therefore, the parabolic equation method is used as a calculation method for the propagation of electromagnetic disturbance in a large area and complex environment.

[0092] However, for boundary problems such as rough surfaces, if the grid is large, SSFT-PE will have certain errors, while the alternating direction implicit (ADI)-parabolic equation (ADI-PE) has more advantages in numerical accuracy when solving complex boundaries. Therefore, the SSFT solution is used to predict the electromagnetic disturbance propagation characteristics in flat terrain space. In addition, for complex terrain, the alternating direction implicit-parabolic equation (ADI-PE) method is used to calculate the electromagnetic disturbance propagation characteristics.

[0093] The solution area is divided into the electromagnetic disturbance propagation area in large-scale complex geographical environment and the electromagnetic disturbance propagation area with obstacles.

[0094] Specifically, the above step S102 includes: Figure 4 It is a schematic diagram of a method for constructing an electromagnetic signal propagation area transfer function based on discrete Laplace transform according to an embodiment of the present invention.

[0095] In order to simplify the hybrid process and realize scene switchability and modular simulation, discrete Laplace transform is introduced into the multi-region hybrid method to extract the transfer function of the electromagnetic disturbance propagation characteristics of each region, that is, to transform the prediction of electromagnetic disturbance propagation characteristics into transfer function prediction, thereby realizing scene switchability and modularization requirements.

[0096] For example, it is assumed that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source:

[0097]

[0098] Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c Then, the TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved and used as the output signal y in the TDPE area. PE(t). At the same time, using x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle. DG (t). Then, based on the input and output signals of each area, the discrete Laplace transform is used to obtain the transfer function of different areas. Finally, the transfer functions are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area.

[0099] The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is:

[0100] y(t)=x(t)*h(t) (2)

[0101] The transfer function of the TDPE region can be expressed as:

[0102]

[0103] Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region. Correspondingly, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation.

[0104] Similarly, Figure 4 T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively:

[0105]

[0106] The above method assumes that the distance between obstacles is far enough to ignore the multiple scattering between them. If there is mutual coupling between obstacles, the DGTD method needs to be used to solve the backscattering of obstacles.

[0107] In order to obtain the transfer function of electromagnetic disturbance propagation characteristics, such as Figure 5 As shown in Figure 1, this section uses the System Identification module in the Matlab simulation software, which can quickly solve the system transfer function coefficients based on the input and output signals.

[0108] Step S103, the electromagnetic signal simulation method and device under complex natural environment based on NI virtual instrument includes:

[0109] Specifically, the electromagnetic signal simulation device under complex natural environment based on NI virtual instrument consists of the following components: Figure 6As shown in the figure, the hardware system includes radiation semi-physical simulation, and the interference signal output by the simulation is realized through NI virtual instruments, power amplifiers and transmitting antennas to realize the semi-physical simulation of radiation electromagnetic effects. The LABVIEW program is used to mix the original electromagnetic signal with the complex environmental characteristics to obtain the output signal; the NI virtual instrument processes the numerical calculation simulation data and outputs the signal, thereby realizing the simulation of electromagnetic signals in complex natural environments.

[0110] The embodiments of the present invention provide a method for simulating electromagnetic signals in a complex natural environment, a method for predicting the propagation characteristics of electromagnetic disturbances in a complex multi-region natural environment based on the time-domain discontinuous Galerkin-parabolic equation; a method for constructing a transfer function of an electromagnetic signal propagation region based on discrete Laplace transform; and a method and device for simulating electromagnetic signals in a complex natural environment based on NI virtual instruments. The complex environment electromagnetic effect simulation finally established can accurately simulate the real electromagnetic environment of the external field, and the electromagnetic signal interference to the equipment in a complex natural environment is simulated by the simulation device, solving the problem of indoor simulation equivalently replacing the external field test in an environment with complex structural obstacles.

[0111] In this embodiment, a method for simulating electromagnetic signals in a complex natural environment is provided, which can be used in servers, such as desktop computers, tablet computers, etc. Figure 2 is a flow chart of a method for simulating electromagnetic signals under a complex natural environment according to an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0112] Step S201, a method for predicting electromagnetic disturbance propagation characteristics in a complex multi-region natural environment based on a time-domain discontinuous Galerkin-parabolic equation.

[0113] Specifically, the above step S201 includes:

[0114] Step S2011, decomposing the solution area into a large-area electromagnetic disturbance propagation area (TDPE area) and an obstacle forward scattering area (DGTD area).

[0115] Specifically, the parabolic equation method (PE) is obtained by approximating Maxwell's wave equations. Compared with the high-frequency approximation algorithm, the parabolic equation method fully considers the effects of electromagnetic wave refraction and diffraction, and at the same time processes the refractive index term for environmental effects such as complex geographical environment and meteorological environment. However, for boundary problems such as rough surfaces, if the grid is large, SSFT-PE will have certain errors, while the alternating direction implicit (ADI)-parabolic equation (ADI-PE) has more advantages in numerical accuracy when solving complex boundaries. Therefore, the solution area is first divided according to the complexity of the terrain.

[0116] Step S2012, using the time domain parabolic equation (TDPE) method to calculate the propagation characteristics of electromagnetic disturbance signals in large-scale complex meteorological and topographic environments. In this area, the SSFT solution is used to predict the electromagnetic disturbance propagation characteristics in a flat terrain space.

[0117] In an optional implementation, the above step S2012 includes:

[0118] Step a1, taking the large-area electromagnetic disturbance propagation area as the first solution area, and using the scalar ψ to represent any field component of E or H, it satisfies the scalar Helmholtz equation:

[0119]

[0120] Step a2, assuming that the electromagnetic wave propagates along the x-axis, define the wave function along the positive direction of the x-axis as:

[0121]

[0122] Substituting equation (6) into equation (5) yields:

[0123]

[0124] in Split the above formula into In the pair Using the Feit-Fleck approximation, The three-dimensional forward parabola equation can be obtained as:

[0125]

[0126] Formula 7 is a first-order partial differential equation about x. Assuming the initial value of u(x, y, z) is u(x0, y, z), solving Formula 8 yields:

[0127]

[0128] Separating the refractive index term and the constant term from Equation 9 yields:

[0129]

[0130] The two-dimensional Fourier transform and inverse transform on the YOZ plane are defined as:

[0131]

[0132] After sorting, we can get:

[0133]

[0134] Step a3, assuming that the atmosphere is a uniform medium distribution, after performing two-dimensional Fourier transform and inverse transform on both sides of equation 10, the solution formula of the SSFT solution of the three-dimensional parabolic equation can be obtained as follows:

[0135]

[0136] Step S2013, using the time domain discontinuous Galerkin (DGTD) method to calculate the time domain scattering field of electromagnetic waves when propagating to the area with complex structural obstacles. For complex boundaries, the ADI-PE method with higher solution accuracy is used to calculate the complex boundary area.

[0137] In an optional implementation, step S2013 includes:

[0138] Step b1, Figure 7 Schematic diagram of the space stepping of the alternating direction implicit solution.

[0139] x i ,y j 、z k Corresponding to the mesh nodes in three directions of three dimensions, and:

[0140] x i =iΔx, i=0,1……,N x

[0141] y j =jΔy, j=0,1……,N y

[0142] z k =kΔz, k=0,1……,N z

[0143] Step b2, set i Point x i-1 and x i An intermediate position between:

[0144]

[0145] According to the definition of central difference, the first-order partial derivative in the x direction can be derived as:

[0146]

[0147] In the formula represents u(x i ,y j ,z k ).

[0148] At the same time, the second-order partial derivatives in the central difference approximation equation have the following form:

[0149]

[0150] Take i The field value at the distance is the two whole grid distance points before and after x i-1 and x i The average value of the field value, that is:

[0151]

[0152] In the 3D rectangular coordinate system, the standard PE is:

[0153]

[0154] Position (ξ i ,y j ,z k ) After differentiation, use equations 15, 16, and 17 to substitute into equation 18, and then we can get:

[0155]

[0156] Rearrange equation 19 as follows:

[0157] (1-r y δ y -r z δ z ) i =(1+r y δ y +r z δ z ) i-1 (20)

[0158] in:

[0159]

[0160] Equation 20 is further transformed into:

[0161] (1-ry δ y -r z δ z +r y r z δ y δ z ) i =(1+r y δ y +r z δ z +r y r z δ y δ z ) i-1

[0162] r y r z δ y δ z (u i -u i-1 )+O(ΔzΔx 2 )+O(ΔyΔx 2 )+O(Δx 3 )(twenty four)

[0163] The O(*) term represents the n-order error. The error term can be ignored. At the same time, in order to facilitate subsequent programming, the two steps before and after in equation 24 are separated to both sides of the equal sign, and we can get:

[0164] (1-r y δ y )(1-r z δ z ) i =(1+r y δ y )(1+r z δ z ) i-1 (25)

[0165] Step b3, for the solution of the ADI method, an intermediate stepping surface is added between the two surfaces. Its main function is to facilitate the mathematical solution and has no specific physical meaning. Figure 7 As shown, the field on the step surface i-1 / 2 is assumed to be

[0166] Then, equation 25 is decomposed into two equations:

[0167]

[0168] Substituting equation 26 into equation 25 and rearranging it, we can obtain:

[0169]

[0170] Equation 27 is the specific expression of the alternating direction implicit solution.

[0171] Step S202: A method for constructing an electromagnetic signal propagation region transfer function based on discrete Laplace transform.

[0172] Specifically, the above step S202 includes:

[0173] Step S2021, using the TDPE method to calculate the propagation process of electromagnetic waves in complex meteorological and topographical environments, and solving the time domain signal near the obstacle, and using this as the output signal of the TDPE area.

[0174] In an optional implementation, step S2021 includes:

[0175] Specifically, it is assumed that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source:

[0176]

[0177] Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c Then, the TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved and used as the output signal y in the TDPE area. PE (t).

[0178] Step S2022: Calculate the forward time-domain scattering field of each obstacle using the DGTD method.

[0179] In an optional implementation, step S2022 includes:

[0180] Specifically, taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle. DG (t)

[0181] Step S2023: Based on the input and output signals of each region, discrete Laplace transform is used to obtain the transfer functions of different regions.

[0182] Step S2024: cascade the transfer functions to obtain the transfer function of the entire electromagnetic disturbance propagation area.

[0183] In an optional implementation, step S2024 includes:

[0184] Specifically, the signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is:

[0185] y(t)=x(t)*h(t) (29)

[0186] The transfer function of the TDPE region can be expressed as:

[0187]

[0188] Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region. Correspondingly, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation.

[0189] Similarly, Figure 4 T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively:

[0190]

[0191] The above method assumes that the distance between obstacles is far enough to ignore the multiple scattering between them. If there is mutual coupling between obstacles, the DGTD method needs to be used to solve the backscattering of obstacles.

[0192] Step S203: Method and device for simulating electromagnetic signals in complex natural environments based on NI virtual instruments. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0193] This embodiment provides a method for calculating the propagation process of electromagnetic waves in complex meteorological and topographical environments using the TDPE method, and solving the time domain signal near the obstacle, and using this as the output signal of the TDPE area; using the DGTD method to calculate the forward time domain scattering field of each obstacle; based on the input and output signals of each area, using discrete Laplace transform to obtain the transfer function of different areas; cascading the transfer functions to obtain the transfer function of the entire electromagnetic disturbance propagation area. This provides a basis for the subsequent realization of electromagnetic signal simulation in complex natural environments.

[0194] In this embodiment, a method for simulating electromagnetic signals in a complex natural environment is provided, which can be used in servers, such as desktop computers, tablet computers, etc. Figure 3 is a flow chart of a method for simulating electromagnetic signals under a complex natural environment according to an embodiment of the present invention. Figure 3 As shown, the process includes the following steps:

[0195] Step S301, using LABVIEW program to mix the original electromagnetic signal with the complex environment characteristics to obtain an output signal.

[0196] Specifically, the above step S301 includes:

[0197] Step S3011, reading the measured electromagnetic environment data of the device end, and reconstructing the waveform based on the waveform data file.

[0198] Step S3012: Mix the original environment data of the device with the transfer function representing the electromagnetic characteristics of the complex environment to obtain the electromagnetic signal of the device in the complex natural environment.

[0199] Step S302: The NI virtual instrument processes the numerical calculation simulation data and outputs a signal. Figure 1 Step S103 of the illustrated embodiment will not be described in detail here.

[0200] The electromagnetic signal simulation method under complex natural environment provided in this embodiment uses LABVIEW program to mix the original electromagnetic signal with the complex environment characteristics to obtain the output signal; the NI virtual instrument processes the numerical calculation simulation data and outputs the signal, thereby realizing the electromagnetic signal simulation under complex natural environment.

[0201] In this embodiment, a device for simulating electromagnetic environmental effects under different environments is also provided, and the device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0202] The structure of an electromagnetic signal simulation device in a complex multi-region natural environment provided by an embodiment of the present invention is as follows: Figure 8 As shown, it includes: a first calculation module, a second calculation module and a third calculation module;

[0203] The first calculation module obtains the characteristic parameters of the terrain, landform and meteorological conditions of the complex multi-region natural environment, and uses the time domain discontinuous Galerkin-parabolic DGTD method and the parabolic equation PE method to perform spatial discretization and numerical calculation according to the characteristic parameters to obtain the electromagnetic disturbance propagation characteristic data of each region;

[0204] The second calculation module obtains the transfer functions of different regions by using discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each region, and cascades the transfer functions of each region to obtain the transfer function of the entire electromagnetic disturbance propagation region;

[0205] The third calculation module uses the LABVIEW program to mix the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, and uses NI virtual instruments and radiation semi-physical simulation devices to simulate the output signal to obtain the simulated electromagnetic signal of the complex multi-region natural environment.

[0206] In some optional implementations, the first calculation module is specifically used to obtain characteristic parameters of terrain, landform and meteorological conditions of a complex multi-region natural environment, and perform spatial discretization and numerical calculation using the DGTD method and the PE method according to the various characteristic parameters obtained;

[0207] For flat terrain, the step-by-step Fourier transform SSFT-PE method is used to calculate the propagation process of electromagnetic waves and predict the electromagnetic disturbance propagation characteristics in flat terrain space.

[0208] For complex terrain and rough surface, the alternating direction implicit ADI-PE method is used to calculate the electromagnetic disturbance propagation characteristics;

[0209] Calculate the time domain signal near the obstacle as the output signal of the TDPE area. If there is mutual coupling between obstacles, use the DGTD method to solve the backscattering of the obstacle.

[0210] Output electromagnetic disturbance propagation characteristic data of each area, the electromagnetic disturbance propagation characteristic data including the frequency, intensity, waveform, propagation path and phase information of the interference signal, and the time domain signal near the obstacle. In some optional embodiments, the second calculation module is specifically used to obtain the transfer function of different areas by discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data of each area, the input electromagnetic signal and the output electromagnetic signal, cascade the transfer function of each area, and obtain the transfer function of the entire electromagnetic disturbance propagation area, including:

[0211] Assume that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source:

[0212]

[0213] Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c is the center frequency

[0214] The TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved, and this time domain signal is used as the output signal y of the TDPE area. PE (t), taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle DG(t), based on the input and output signals of each area, the transfer functions of different areas are obtained by discrete Laplace transform, and the transfer functions of different areas are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area;

[0215] The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is:

[0216] y(t)=x(t)*h(t) (2)

[0217] The transfer function of the TDPE region is expressed as:

[0218]

[0219] Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation.

[0220] Assuming that the distance between obstacles is far enough to ignore the multiple scattering between them, T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively:

[0221]

[0222] T DG (z) is the transfer function of the DGTD region, x(z) and y DG (z) are the input and output discrete time domain signals x(k) and y of the DGTD region, respectively. DG (k) The result after Z-transformation.

[0223] If there is mutual coupling between obstacles, the DGTD method is used to solve the backscattering of the obstacles.

[0224] In some optional embodiments, the third calculation module is specifically used to mix the original electromagnetic signal of the entire electromagnetic disturbance propagation area and the characteristic parameters of the complex natural environment using the LABVIEW program according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, perform analog data processing on the output signal through the NI virtual instrument, and output a simulated electromagnetic signal.

[0225] The simulated electromagnetic signal is processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to implement a radiation-type electromagnetic effect semi-physical simulation process, thereby obtaining the simulated electromagnetic signal of the complex multi-region natural environment.

[0226] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0227] The electromagnetic signal simulation device under complex natural environment in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0228] The embodiment of the present invention also provides a computer device having the above Figure 8 The electromagnetic signal simulation device in the complex multi-region natural environment is shown. Fig. 9 , Fig. 9 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig. 9 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig. 9 A processor 10 is taken as an example.

[0229] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0230] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0231] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0232] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0233] The computer device further includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means.

[0234] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0235] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0236] In summary, the electromagnetic signal simulation under complex natural environment finally established by the present invention can accurately simulate the real electromagnetic environment of the external field, and solves the problem of indoor simulation equivalently replacing the external field test in the environment with complex structural obstacles.

[0237] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0238] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention or certain parts of the embodiments.

[0239] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0240] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for simulating electromagnetic signals in a complex multi-region natural environment, characterized in that: include: Obtain the characteristic parameters of terrain, landform and meteorological conditions of complex multi-regional natural environment, and use the time domain discontinuous Galerkin-parabolic DGTD method and parabolic equation PE method to perform spatial discretization and numerical calculation based on the characteristic parameters to obtain electromagnetic disturbance propagation characteristic data of each region; According to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each area, the transfer function of different areas is obtained by using discrete Laplace transform, and the transfer function of each area is cascaded to obtain the transfer function of the entire electromagnetic disturbance propagation area; According to the transfer function of the entire electromagnetic disturbance propagation area, the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area are mixed using the LABVIEW program to obtain an output signal, and the output signal is simulated by using a virtual instrument NI and a radiation semi-physical simulation device to obtain a simulated electromagnetic signal of the complex multi-region natural environment.

2. The method according to claim 1, characterized in that: The method of obtaining the characteristic parameters of terrain, landform and meteorological conditions of a complex multi-regional natural environment, and performing spatial discretization and numerical calculation using the DGTD method and the PE method according to the characteristic parameters to obtain the electromagnetic disturbance propagation characteristic data of each region includes: Obtain the characteristic parameters of terrain, geomorphology and meteorological conditions of complex multi-regional natural environments, and use the DGTD method and PE method to perform spatial discretization and numerical calculation based on the various characteristic parameters obtained; For flat terrain, the step-by-step Fourier transform SSFT-PE method is used to calculate the propagation process of electromagnetic waves and predict the electromagnetic disturbance propagation characteristics in flat terrain space. For complex terrain and rough surface, the alternating direction implicit ADI-PE method is used to calculate the electromagnetic disturbance propagation characteristics; Calculate the time domain signal near the obstacle as the output signal of the TDPE area. If there is mutual coupling between obstacles, use the DGTD method to solve the backscattering of the obstacle. Output electromagnetic disturbance propagation characteristic data of each area, wherein the electromagnetic disturbance propagation characteristic data includes the frequency, intensity, waveform, propagation path and phase information of the interference signal, and the time domain signal near the obstacle.

3. The method according to claim 2, characterized in that The method of obtaining the transfer functions of different regions by using discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data, input electromagnetic signals and output electromagnetic signals of each region, and cascading the transfer functions of each region to obtain the transfer function of the entire electromagnetic disturbance propagation region includes: Assume that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source: Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c is the center frequency The TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved, and this time domain signal is used as the output signal y of the TDPE area. PE (t), taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle DG (t), based on the input and output signals of each area, the transfer functions of different areas are obtained by discrete Laplace transform, and the transfer functions of different areas are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area; The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is: y(t)=x(t)*h(t) (2) The transfer function of the TDPE region is expressed as: Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation. Assuming that the distance between obstacles is far enough to ignore the multiple scattering between them, T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively: T DG (z) is the transfer function of the DGTD region, x(z) and y DG (z) are the input and output discrete time domain signals x(k) and y of the DGTD region, respectively. DG (k) The result after Z transformation; If there is mutual coupling between obstacles, the DGTD method is used to solve the backscattering of the obstacles.

4. The method according to claim 3, characterized in that The method of using the LABVIEW program to mix the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, and using NI virtual instruments and radiation-type semi-physical simulation devices to simulate the output signal to obtain the simulated electromagnetic signal of the complex multi-region natural environment includes: According to the transfer function of the entire electromagnetic disturbance propagation area, the original electromagnetic signal of the entire electromagnetic disturbance propagation area and the characteristic parameters of the complex natural environment are mixed using the LABVIEW program to obtain an output signal, and the output signal is simulated data processed by the NI virtual instrument to output a simulated electromagnetic signal; The simulated electromagnetic signal is processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to implement a radiation-type electromagnetic effect semi-physical simulation process, thereby obtaining the simulated electromagnetic signal of the complex multi-region natural environment.

5. An electromagnetic signal simulation device in a complex multi-region natural environment, characterized in that: include: A first computing module, a second computing module, and a third computing module; The first calculation module obtains the characteristic parameters of the terrain, landform and meteorological conditions of the complex multi-region natural environment, and uses the time domain discontinuous Galerkin-parabolic DGTD method and the parabolic equation PE method to perform spatial discretization and numerical calculation according to the characteristic parameters to obtain the electromagnetic disturbance propagation characteristic data of each region; The second calculation module obtains the transfer functions of different regions by using discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data, input electromagnetic signal and output electromagnetic signal of each region, and cascades the transfer functions of each region to obtain the transfer function of the entire electromagnetic disturbance propagation region; The third calculation module uses the LABVIEW program to mix the original electromagnetic signal and characteristic parameters of the entire electromagnetic disturbance propagation area according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, and uses NI virtual instruments and radiation semi-physical simulation devices to simulate the output signal to obtain the simulated electromagnetic signal of the complex multi-region natural environment.

6. The device according to claim 5, characterized in that: The first calculation module is specifically used to obtain the characteristic parameters of the terrain, landform and meteorological conditions of the complex multi-region natural environment, and use the DGTD method and the PE method to perform spatial discretization and numerical calculation according to the various characteristic parameters obtained; For flat terrain, the step-by-step Fourier transform SSFT-PE method is used to calculate the propagation process of electromagnetic waves and predict the electromagnetic disturbance propagation characteristics in flat terrain space. For complex terrain and rough surface, the alternating direction implicit ADI-PE method is used to calculate the electromagnetic disturbance propagation characteristics; Calculate the time domain signal near the obstacle as the output signal of the TDPE area. If there is mutual coupling between obstacles, use the DGTD method to solve the backscattering of the obstacle. Output electromagnetic disturbance propagation characteristic data of each area, wherein the electromagnetic disturbance propagation characteristic data includes the frequency, intensity, waveform, propagation path and phase information of the interference signal, and the time domain signal near the obstacle.

7. The device according to claim 6, characterized in that: The second calculation module is specifically used to obtain the transfer functions of different regions by discrete Laplace transform according to the electromagnetic disturbance propagation characteristic data of each region, the input electromagnetic signal and the output electromagnetic signal, and cascade the transfer functions of each region to obtain the transfer function of the entire electromagnetic disturbance propagation region, including: Assume that a sinusoidally modulated Gaussian pulse signal is used as the interference signal excitation source: Where A is the signal amplitude, T is the pulse period, t0 is the delay, and f c is the center frequency The TDPE method is used to calculate the propagation process of electromagnetic waves in complex meteorological and terrain environments, and the time domain signal near the obstacle is solved, and this time domain signal is used as the output signal y of the TDPE area. PE (t), taking x(t) as the excitation source, the DGTD method is used to calculate the forward time-domain scattering field y of each obstacle DG (t), based on the input and output signals of each area, the transfer functions of different areas are obtained by discrete Laplace transform, and the transfer functions of different areas are cascaded to obtain the transfer function H(z) of the entire electromagnetic disturbance propagation area; The signal at the observation point after the electromagnetic disturbance signal passes through the obstacle environment in the large-scale scene can be considered as the convolution of the initial signal and the transfer function, that is: y(t)=x(t)*h(t) (2) The transfer function of the TDPE region is expressed as: Where Z(*) represents the Z transform, x(k) and y PE (k) are the input and output discrete time domain signals of the TDPE region, x(z) and y PE (z) are x(k) and y respectively PE (k) The result after Z-transformation. Assuming that the distance between obstacles is far enough to ignore the multiple scattering between them, T1(z) and T2(z) are the system transfer functions of two multi-scale obstacles respectively: T DG (z) is the transfer function of the DGTD region, x(z) and y DG (z) are the input and output discrete time domain signals x(k) and y of the DGTD region, respectively. DG (k) The result after Z transformation; If there is mutual coupling between obstacles, the DGTD method is used to solve the backscattering of the obstacles.

8. The device according to claim 7, characterized in that: The third calculation module is specifically used to mix the original electromagnetic signal of the entire electromagnetic disturbance propagation area and the characteristic parameters of the complex natural environment using the LABVIEW program according to the transfer function of the entire electromagnetic disturbance propagation area to obtain an output signal, perform analog data processing on the output signal through the NI virtual instrument, and output a simulated electromagnetic signal; The simulated electromagnetic signal is processed by a radiation-type semi-physical simulation device through a power amplifier and a transmitting antenna to implement a radiation-type electromagnetic effect semi-physical simulation process, thereby obtaining the simulated electromagnetic signal of the complex multi-region natural environment.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the electromagnetic signal simulation method in a complex multi-region natural environment as described in any one of claims 1 to 4 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the electromagnetic signal simulation method in a complex multi-region natural environment as described in any one of claims 1 to 4.

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