An integrated electronic test field electromagnetic interference simulation analysis method based on UE4 engine

Abstract

This invention provides a comprehensive electromagnetic interference simulation and analysis method for electronic test fields based on the UE4 engine, belonging to the field of electromagnetic interference analysis. Addressing the interference analysis needs of frequency-using equipment, this invention considers the near-field and far-field regions of the equipment model, establishing transmitter and receiver models based on the UE4 platform. Simultaneously, it considers static factors such as hillsides and trees, as well as dynamic factors such as weather and time, to establish a three-dimensional geographical environment model. The electromagnetic interference analysis method of this invention includes the finite-difference time-domain method, uniform diffraction theory, geometric diffraction theory, and ray tracing model, considering interference types such as fundamental frequency interference, harmonic interference, intermodulation interference, and spurious signal interference, and conducting interaction and interference analysis of equipment within the test field. This invention can comprehensively consider various factors of simultaneous testing in an electronic test field, define a set of frequency usage evaluation indicators, establish a management evaluation model, and achieve accurate modeling and evaluation of the current equipment layout and scheduling within the test field.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic interference analysis, specifically relating to a comprehensive electronic test field electromagnetic interference simulation analysis method based on the UE4 engine. Background Technology

[0002] Electromagnetic interference (EMC) refers to the interference phenomenon caused by the interaction of electromagnetic waves with electronic components. There are two types: conducted interference and radiated interference. Conducted interference refers to the coupling (interference) of a signal from one electrical network to another through a conductive medium. Radiated interference refers to the coupling (interference) of a signal from an interference source to another electrical network through space. In high-speed PCB and system design, high-frequency signal lines, integrated circuit pins, and various connectors can all become sources of radiated interference with antenna characteristics, emitting electromagnetic waves and affecting the normal operation of other systems or subsystems within the same system. In wireless communication systems, transmitters generate out-of-band electromagnetic radiation such as adjacent channels and spurious signals while transmitting useful signals; while receivers receive useful signals, they may not only be blocked by interference signals falling within their bandwidth, but also experience out-of-band blocking due to the nonlinearity of the receiver. Therefore, the inherent frequency interference in wireless technology leads to significant electromagnetic compatibility (EMC) issues.

[0003] Electromagnetic interference analysis analyzes the mutual interference between communication devices. In electronic test ranges, which require testing of multiple types of equipment for communication, countermeasures, and other disciplines, there are problems such as high test frequency, serious frequency conflicts, and limited space layout. By using various interference analysis methods such as computational electromagnetics and far-field analysis technology, it can provide basic support for adjusting the time, space, and frequency layout of equipment in the test range. Summary of the Invention

[0004] In view of this, this invention provides a simulation analysis method for electromagnetic interference in a comprehensive electronic test field based on the UE4 engine. Addressing issues such as high test frequency, severe frequency conflicts, and limited spatial layout within the test field, this invention employs various interference analysis techniques, including computational electromagnetics and far-field analysis. It optimizes and adjusts the spatial, temporal, and frequency parameters of equipment within the test field through corresponding algorithms, and performs corresponding evaluations and demonstrations, thus completing the simulation analysis of optimized design and resource scheduling for a large-scale comprehensive electronic test field. Simultaneously, this invention uses UE4 to perform 3D modeling of the environment and equipment within the test field, solving the problem of visualizing the interactions between equipment in the electronic test field.

[0005] This invention is achieved through the following technical solution:

[0006] A comprehensive electronic test field electromagnetic interference simulation and analysis method based on the UE4 engine includes the following steps:

[0007] Step 1: Establish a model of the device under test based on the actual production environment, and design the transmitter model and receiver model through the UE4 platform;

[0008] Step 2: Based on the model of the device under test, establish a three-dimensional geographic environment model based on the UE4 platform;

[0009] Step 3: Divide the near and far fields of the wireless communication environment and electromagnetic radiation area in the three-dimensional geographic environment model, construct the electromagnetic signal propagation mechanism, determine the environmental change parameters, and establish an electromagnetic transmission loss model.

[0010] Step 4: Analyze the electromagnetic interference principle of the electromagnetic transmission loss model;

[0011] Step 5: Perform near-field and far-field analysis on the model of the device under test. If it is near-field, use the finite-difference time-domain method for near-field interference analysis; if it is far-field, use geometric diffraction theory, uniform diffraction theory, and ray tracing method for far-field interference analysis.

[0012] Furthermore, in step 1, the transmitter model and receiver model are designed, including: establishing the transmitter fundamental signal model, the transmitter harmonic signal model, and the transmitter non-harmonic signal model; establishing the receiver sensitivity model, the receiver intermodulation signal model, and the receiver scrambled signal model; and setting the response parameters of different models.

[0013] Furthermore, in step 2, a three-dimensional geographic environment model based on the UE4 platform is established, including: establishing the terrain environment of hillsides and plains, establishing physical entities of trees and grass, designing weather change rules for sunny days, rainy days, and cloudy days, and setting day-night cycle and time acceleration functions.

[0014] Further, step 3 specifically involves: dividing the electromagnetic radiation region into a far-field region and a near-field region based on the size of the radiation source antenna and the transmission wavelength of different devices; setting different dielectric constants and conductivity for different terrains and weather conditions; and further dividing the electromagnetic interference propagation process into free-space propagation, skywave propagation, groundwave propagation, and diffraction propagation.

[0015] The near-field and far-field separation threshold R of the electromagnetic radiation region is:

[0016]

[0017] In the formula, D is the antenna size and λ is the wavelength;

[0018] When the distance d between the transmitter and receiver is greater than R, the electromagnetic radiation region is classified as the far field. At this time, the interference propagation path is analyzed and the interference power is calculated based on the free space path loss model. When the distance d is less than R, the electromagnetic radiation region is classified as the near field. At this time, the finite-difference time-domain method is used to discretize the electric and magnetic field regions in a grid and calculate the electromagnetic field value of the receiver.

[0019] Further, step 4 specifically involves: referring to the electromagnetic interference source and the sensitive device as the transmitter and receiver, respectively; referring to the magnitude of the interference power coupled from the interference source to the sensitive device as the interference quantity; determining whether a potential electromagnetic interference environment exists in the system by comparing the effective interference power of the transmitter acting on the receiver and the receiver's sensitivity threshold; describing the degree of interference received by the receiver using interference margin, which is calculated using the following formula:

[0020] IM(f E ,t)=P E -S(f E )

[0021] In the formula, IM(f E ,t) represents the receiver's interference margin, in dB; P E S(f) represents the effective interference power coupled from the transmitter to the receiver antenna port, expressed in dBm. E The value is the receiver's sensitivity, expressed in dBm.

[0022] The electromagnetic interference environment of a communication system is divided into three levels: IM>0 indicates that the system is subject to interference and there is a potential electromagnetic interference environment; IM=0 indicates that the system is at the critical level of interference and it is impossible to determine whether there is an electromagnetic interference environment; IM<0 indicates that the system is in a compatible state and there is no electromagnetic interference environment.

[0023] Furthermore, step 5 specifically includes:

[0024] The calculation covers the near and far field ranges of the computing device. If the interference is near field, the electric and magnetic fields are discretized into a grid using the finite-difference time-domain method. Computational boundaries and parameters are set, electromagnetic field coefficients are calculated, and the electromagnetic field value is calculated using the central difference discretization equation. Absorption boundary conditions are applied, and the process is iterated until the final electromagnetic field value is output. The finite-difference time-domain method includes a set of time-domain advancement formulas, which are obtained by performing a difference discretization operation on the differential form of Maxwell's equations.

[0025] f(x,y,z,t)=f(iΔx,jΔy,kΔz,nΔt)=f n (i,j,k)

[0026] In the formula, Δx, Δy, and Δz represent the spatial intervals of the rectangular grid along the x, y, and z directions, respectively; Δt is the time interval; and i, j, k, and n are integers.

[0027] If it is far-field interference, the interference propagation path is analyzed based on the spatial location of the interfering and affected devices:

[0028] If it is a direct interference path, then the direct interference power is calculated according to the free space path loss model:

[0029]

[0030] In the formula, P E To receive the interference power at the front end of the device, P T (f E ) is f E Transmit interference power at a given frequency This represents the gain of the transmitting antenna in the receiving direction. Let θ be the gain of the receiving antenna in the transmitting direction, where θ T θ R Represents the horizontal azimuth angle of the antenna. L(f) represents the antenna elevation angle; E ,t,d,p) represents the propagation path loss, where p is a parameter such as spatial obstacles or medium characteristics.

[0031] If it is a reflection interference path, calculate the reflection coefficient based on the reflection point location, and finally calculate the reflected electromagnetic field strength; the formula for calculating the reflection coefficient is:

[0032]

[0033]

[0034] Among them, R ⊥ and R / / θ1 represents the reflection coefficients of the vertically polarized wave and the parallelly polarized wave, respectively; θ2 is the incident angle, and θ3 is the complex permittivity of the medium. j represents the imaginary part of the complex function, where Let be the relative permittivity of the incident medium. Let be the relative permittivity of the outgoing medium; e is the permittivity, σ is the conductivity of the reflecting surface, and w is the angular frequency; assuming S is a field point on the reflected ray at a distance s from the reflection point Q, then the final field of the reflected wave at field point S is:

[0035]

[0036] In the formula, The diffusion factor is s', which is the distance between the source point and the reflection point Q, and s is the distance between the reflection point Q and the field point. This represents the incident final wave field at reflection point Q. This represents the final wavefield at the receiving point S; Represents the reflection coefficient, which is divided into the vertically polarized wave reflection coefficient R. ⊥ and parallel polarized wave reflection coefficient R / / Two parts, j represents the imaginary part of the complex function, and k is the wave number.

[0037] If it is a diffraction interference path, then calculate the diffraction coefficient based on the location of the diffraction point, and finally calculate the diffracted electromagnetic field strength; the formula for calculating the diffraction coefficient is:

[0038]

[0039]

[0040] In the formula, D s D is the diffraction coefficient for vertically polarized waves. h denoted as the diffraction coefficient for horizontally polarized waves; j represents the imaginary part of the complex function; n is the wedge factor, which is 3 / 2 at a 90-degree angle; k is the wave number; β0 is the angle between the incident ray and the wedge; where,

[0041]

[0042] In the formula L i L d Let F(X) be the distance parameter and F(X) be the transition function, which is expressed as:

[0043]

[0044]

[0045] Among them, a ± (β) is the diffraction coefficient correlation function, β = β ± =φ±φ', where φ is the angle between the incident wave at the diffraction point and the edge of the object, φ' is the angle between the diffracted wave at the diffraction point and the edge of the object, and j represents the imaginary part of the complex function; N ± It is the integer that is closest to satisfying the following equation:

[0046] 2nπN + -β ± ≈π

[0047] 2nπN - -β ± ≈-π

[0048] α is the radius of curvature. For a right-angled wedge, as the radius of curvature α of the diffracted object's edge approaches infinity, then...

[0049] Assuming P is an arbitrary point on the diffracted ray, and its distance from the diffracting point M is s, then the field strength at the diffracting point is:

[0050]

[0051] in, For the final field of the diffracted wave, This represents the final field of the incident wave at the diffraction point. The diffraction coefficient is denoted as D. s and D h Two parts;

[0052] If it is a transmission interference path, calculate the transmission coefficient based on the transmission point location, and finally calculate the transmitted electromagnetic field intensity; vertical polarization transmission coefficient T ⊥ and horizontal polarization transmission coefficient T / / The calculation formula is:

[0053]

[0054]

[0055] In the formula, θ i Let θ be the angle of incidence. t The refraction angle is the transmission angle; when the medium is lossy, the refraction angle is a complex number, γ1 sinθ. i =γ2sinθ t γ1 is the refractive index of the incident medium, γ2 is the refractive index of the transmitting medium, where γ is the propagation constant, γ = α + jβ, the real part α is the attenuation constant, and the imaginary part β is the phase constant; η is the wave impedance. η is the complex permittivity; η1 is the incident medium wave impedance, and η2 is the transmitted medium wave impedance;

[0056] Assuming the total path distance of the ray before penetration at point Q is s, then the final field of the transmitted wave at point Q is... The final field of the incident wave at reflection point Q The relationship is:

[0057]

[0058] in, The incident wave transmission coefficient, Let d' be the transmission coefficient of the outgoing wave, d' be the distance the ray travels in the medium, and j represent the imaginary part of the complex function.

[0059] Finally, the effective interference power is calculated based on the electromagnetic field strength, and the interference intensity is analyzed based on the interference margin.

[0060] The beneficial effects of this invention are:

[0061] 1. This invention comprehensively considers electromagnetic interference analysis methods and establishes a three-dimensional device and environment model based on UE4, which can comprehensively and accurately reflect the parameters required for interference analysis. The device model can be divided into near-field and far-field regions.

[0062] 2. This invention comprehensively considers the far-field and near-field regions of the equipment, and is based on information such as various frequency usage regulations, surrounding electromagnetic environment data, and actual experience data. It combines information such as the models of each participating equipment, the site environment model, the specific layout location of the equipment, and the equipment mounting height, and uses various interference simulation analysis methods to conduct interaction and interference analysis of equipment in the field area. It can accurately simulate the interference between various equipment models in the electronic test field. Attached Figure Description

[0063] Figure 1 This is a schematic diagram illustrating the principle of the present invention.

[0064] Figure 2 This is the meshed diagram generated by the finite-difference time-domain method of this invention. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] Example 1

[0067] A comprehensive electronic test field electromagnetic interference simulation and analysis method based on the UE4 engine analyzes the mutual interference between devices within the test field using computational electromagnetics methods and far-field analysis techniques. For each device, it performs near-field electromagnetic field strength calculation and analysis, as well as far-field interference type analysis. Based on the device communication status, it analyzes potential interference, providing technical support for subsequent frequency evaluation and optimization of the test field. The method includes the following steps:

[0068] Step 1: Establish a model of the device under test based on the actual production environment, and design the fundamental signal model, harmonic signal model, intermodulation signal model, and spurious signal model;

[0069] Step 2: Based on Step 1, establish a three-dimensional geographic environment model, deploy the equipment model into the environment model, and construct a basic environmental analysis model;

[0070] Step 3: Construct environmental and equipment parameters for the environmental basic analysis model in Step 2, and establish an electromagnetic transmission loss model;

[0071] Step 4: Perform principle analysis on the analysis model based on the actual production environment in Step 3, and calculate the near and far field ranges of the equipment to be tested in the field area;

[0072] Step 5: Perform near-field and far-field analysis on the device under test in Step 4. If it is near-field, use the finite-difference time-domain method for near-field interference analysis; if it is far-field, use geometric diffraction theory, uniform diffraction theory, and ray tracing method for far-field interference analysis, and calculate the direct, reflected, diffracted, and transmitted electromagnetic fields.

[0073] Example 2

[0074] A comprehensive electronic test field electromagnetic interference simulation and analysis method based on the UE4 engine, from Figure 1 As can be seen, this method first analyzes the attributes of radio wave frequency bands, wavelengths, and propagation modes in the test environment based on the static environmental model. It analyzes possible propagation paths based on terrain factors and determines the propagation model in conjunction with the communication environment. For the specific experimental type and spatial state of the equipment under test within the test area, factors such as fundamental interference, harmonic interference, intermodulation interference, and spurious signal interference are considered. Then, combining the static environmental model of the actual production environment and the model of the equipment under test, electromagnetic interference principle analysis is performed. Appropriate interference analysis methods are selected based on the near and far field ranges of the equipment under test. Next, electromagnetic interference calculation analysis is conducted, calculating the path loss of interfering equipment, analyzing interference types based on environmental and equipment parameters, and calculating possible interference modes such as direct, reflected, diffracted, and transmitted interference. Finally, interference margin is calculated based on the sensitivity of the equipment under test, and interference types are analyzed, providing a basic support for frequency management optimization and adjustment, which is consistent with the goal of this method.

[0075] The first step is to delineate the electromagnetic radiation zone.

[0076] Generally, the electromagnetic radiation field of an electromagnetic radiation source can be divided into the far field and the near field.

[0077]

[0078] Where R represents the boundary between the near and far fields.

[0079] The second step is to calculate the interference propagation path loss.

[0080] Based on the spatial locations of the device under test and the interfering device, the Euclidean distance between them is first calculated to determine whether the electromagnetic interference is far-field or near-field. Next, the interference propagation mode is analyzed to determine if direct, reflected, diffracted, or transmitted interference paths exist, and path loss is calculated based on these paths. If a reflection or diffracted path exists, the reflection coefficient and diffraction coefficient need to be calculated. The path loss model uses the Okumura-Hata model, specifically:

[0081] PL = 69.5 + 29.16log(f) E -13.8logH b -a(H m)+[44.9-6.5logH b logd-K

[0082] Where PL is the path loss, and H is the path loss. b For the effective height of the transmitter, a(H) m H is the receiving antenna height correction factor. m K represents the height of the receiving antenna and K is the city correction factor.

[0083] The third step is to calculate the interference power.

[0084] Using the interference propagation mode analyzed in the first step, calculate the interference power of the interfering device.

[0085] If it is near-field interference, the field strength of the device under test is calculated using the finite-difference time-domain method, and the interference power is calculated based on the field strength.

[0086] First, the electromagnetic space is differentially discretized. Figure 2 It can be seen that by spatially arranging the electric and magnetic field nodes through gridding, according to Maxwell's equations, the discrete equations of the electric field in the x, y, and z axes of each grid point after central difference are as follows:

[0087]

[0088] In the formula,

[0089]

[0090] In the formula, label

[0091]

[0092] In the formula, the labels

[0093] The magnetic field discretization equation after central difference is:

[0094]

[0095] In the formula, the labels

[0096]

[0097] In the formula,

[0098]

[0099] In the formula, the labels CA(m), CB(m), CP(m), and CQ(m) are respectively:

[0100]

[0101]

[0102]

[0103]

[0104] Among them, ε(m), σ(m), μ(m), σ m (m) describes the medium properties of space, and Δt represents the time step.

[0105] After obtaining the electric and magnetic fields, calculate the interference power density:

[0106]

[0107] Where E is the total electric field strength, Z0 = 377Ω.

[0108] If the interference is from the far field, the interference power received by the device under test is calculated based on the path loss. If the interference is from a direct path, the direct interference power is calculated based on the free space path loss model.

[0109]

[0110] In the formula, P E To receive the interference power at the front end of the device, P T (f E () represents the transmitted jamming power. This represents the gain of the transmitting antenna in the receiving direction. For the gain of the receiving antenna in the transmitting direction, L(f) E ,t,d,p) represents the propagation path loss.

[0111] If it is a reflection interference path, calculate the reflection coefficient based on the reflection point location, and finally calculate the reflected electromagnetic field strength; the formula for calculating the reflection coefficient is:

[0112]

[0113]

[0114] Among them, R ⊥ and R / / θ1 is the reflection coefficient for vertically polarized waves and horizontally polarized waves, respectively. θ1 is the incident angle, and θ2 is the complex permittivity of the medium. e is the dielectric constant, σ is the conductivity of the reflecting surface, and ω is the angular frequency. Assuming S is a field point on the reflected ray at a distance s from the reflection point Q, the final field of the reflected wave at field point S is:

[0115]

[0116] In the formula, s' refers to the distance between the source point and the reflection point Q, and s refers to the distance between the reflection point Q and the field point.

[0117] If it is a diffraction interference path, then calculate the diffraction coefficient based on the location of the diffraction point, and finally calculate the diffracted electromagnetic field strength; the formula for calculating the diffraction coefficient is:

[0118]

[0119]

[0120] In the formula, n is the wedge factor, which is 3 / 2 at a 90-degree angle; k is the wave number. β0 is the angle between the incident ray and the wedge.

[0121]

[0122] In the formula L i L d Let F(X) be the distance parameter and F(X) be the transition function, which is expressed as:

[0123]

[0124]

[0125] Wherein, 2nπN + -β ± ≈π,2nπN - -β ± ≈-π,β + =φ+φ′,β - =φ-φ′.

[0126] Assuming P is an arbitrary point on the diffracted ray, and its distance from the diffracting point M is S, then the field strength at the diffracting point is:

[0127]

[0128] If it is a transmission interference path, the transmission coefficient is calculated based on the location of the transmission point, and finally the transmitted electromagnetic field intensity is calculated. The formula for calculating the transmission coefficient is:

[0129]

[0130]

[0131] In the formula, θ i Let θ be the angle of incidence. t The refraction angle is the transmission angle; when the medium is lossy, the refraction angle is a complex number, γ1 sinθ. i =γ2sinθ i Where γ is the propagation constant, γ = α + jβ, the real part α is the attenuation constant, and the imaginary part β is the phase constant. η is the wave impedance. layer. is the complex permittivity.

[0132] Assuming the total path distance of the ray before it penetrates at point Q is S, then the final field of the transmitted wave at point Q is... The final field of the incident wave at reflection point Q The relationship is

[0133]

[0134] Step 4: Calculate the interference margin

[0135] By comparing the effective interference power exerted by the transmitter on the receiver with the receiver's sensitivity threshold, it is determined whether a potential electromagnetic interference environment exists in the system. The degree of interference received by the receiver is described by the interference margin (IM), which is calculated as follows:

[0136] IM(f E ,t)=P E -S(f E )

[0137] Based on the actual type of interference, the fundamental interference margin, transmitter interference margin, receiver interference margin, and spurious interference margin can be calculated:

[0138] Fundamental interference margin:

[0139]

[0140] Transmitter interference margin:

[0141]

[0142] Receiver interference margin:

[0143]

[0144] Hypocrisy margin:

[0145]

[0146] in, G is the transmitter's transmit power. T For the transmit antenna gain, Lbf (f OT d) represents path loss, G R For the receiving antenna gain, P R (f OR ) represents the receiver sensitivity. A and B are constants related to a specific transmitter, and I and J are fundamental receiver constants.

[0147] The free-space propagation loss is calculated based on the frequency of the electromagnetic wave radiated by the interfering transmitter and the distance between the transmitter and the receiver, and the electromagnetic interference margin for each transmit response pair is calculated.

[0148] This invention addresses the interference analysis needs of frequency-using equipment. It considers both near-field and far-field regions of the equipment model, establishing transmitter and receiver models based on the UE4 platform. Simultaneously, it considers static factors such as hillsides and trees, as well as dynamic factors such as weather and time, to create a three-dimensional geographic environment model. The electromagnetic interference analysis methods employed in this invention include the finite-difference time-domain method, uniform diffraction theory, geometric diffraction theory, and ray tracing models. An electromagnetic interference analysis model is established, considering interference types such as fundamental frequency interference, harmonic interference, intermodulation interference, and spurious signal interference, to analyze the interaction and interference between equipment within the test field. This invention comprehensively considers various factors involved in simultaneous testing in an electronic test field, defines a set of frequency usage evaluation indicators, establishes a management evaluation model, and achieves accurate modeling and evaluation of the current equipment layout and scheduling within the test field.

Claims

1. A comprehensive electronic test field electromagnetic interference simulation and analysis method based on the UE4 engine, characterized in that, Includes the following steps: Step 1: Establish a model of the device under test based on the actual production environment, and design the transmitter model and receiver model through the UE4 platform; Step 2: Based on the model of the device under test, establish a three-dimensional geographic environment model based on the UE4 platform; Step 3: Divide the near and far fields of the wireless communication environment and electromagnetic radiation area in the three-dimensional geographic environment model, construct the electromagnetic signal propagation mechanism, determine the environmental change parameters, and establish an electromagnetic transmission loss model. Step 4: Analyze the electromagnetic interference principle of the electromagnetic transmission loss model; Step 5: Perform near-field and far-field analysis on the model of the device under test. If it is near-field, use the finite-difference time-domain method for near-field interference analysis; if it is far-field, use geometric diffraction theory, uniform diffraction theory, and ray tracing method for far-field interference analysis.

2. The method for electromagnetic interference simulation and analysis of a comprehensive electronic test field based on the UE4 engine according to claim 1, characterized in that, In step 1, the transmitter model and receiver model are designed, including: establishing the transmitter fundamental signal model, transmitter harmonic signal model, and transmitter non-harmonic signal model; establishing the receiver sensitivity model, receiver intermodulation signal model, and receiver scrambled signal model; and setting the response parameters of different models.

3. The method for electromagnetic interference simulation and analysis of a comprehensive electronic test field based on the UE4 engine according to claim 1, characterized in that, In step 2, a three-dimensional geographic environment model based on the UE4 platform is established, including: establishing the terrain environment of hillsides and plains, establishing physical entities of trees and grass, designing weather change rules for sunny, rainy, and cloudy days, and setting day-night cycle and time acceleration functions.

4. The method for electromagnetic interference simulation and analysis of a comprehensive electronic test field based on the UE4 engine according to claim 1, characterized in that, Step 3 specifically involves dividing the electromagnetic radiation region into a far-field region and a near-field region based on the size of the radiation source antenna and the emission wavelength of different devices, and setting different dielectric constants and conductivity for different terrains and weather conditions. Furthermore, the propagation process of electromagnetic interference is divided into free space propagation, sky wave propagation, ground wave propagation, and diffraction propagation; The near-field and far-field separation threshold R of the electromagnetic radiation region is: In the formula, Antenna size, Wavelength; When the distance d between the transmitter and receiver is greater than R, the electromagnetic radiation region is classified as the far field. At this time, the interference propagation path is analyzed and the interference power is calculated based on the free space path loss model. When the distance d is less than R, the electromagnetic radiation region is classified as the near field. At this time, the finite-difference time-domain method is used to discretize the electric and magnetic field regions in a grid and calculate the electromagnetic field value of the receiver.

5. The method for electromagnetic interference simulation and analysis of a comprehensive electronic test field based on the UE4 engine according to claim 1, characterized in that, Step 4 specifically involves: referring to the electromagnetic interference source and the sensitive device as the transmitter and receiver, respectively; referring to the magnitude of the interference power coupled from the interference source to the sensitive device as the interference quantity; determining whether a potential electromagnetic interference environment exists in the system by comparing the effective interference power of the transmitter acting on the receiver and the receiver's sensitivity threshold; describing the degree of interference received by the receiver using the interference margin, which is calculated as follows: In the formula, This represents the receiver's interference margin, expressed in dB. The effective interference power coupled from the transmitter to the receiver antenna port, in dBm; The receiver's sensitivity is expressed in dBm. The electromagnetic interference environment of a communication system is divided into three levels: IM > 0 indicates that the system is subject to interference and there is a potential electromagnetic interference environment; IM = 0 indicates that the system is at the critical interference level and it is impossible to determine whether there is an electromagnetic interference environment; IM < 0 indicates that the system is in a compatible state and there is no electromagnetic interference environment.

6. The method for electromagnetic interference simulation and analysis of a comprehensive electronic test field based on the UE4 engine according to claim 1, characterized in that, Step 5 specifically involves: The calculation covers the near and far field ranges of the computing device. If the interference is near field, the electric and magnetic fields are discretized into a grid using the finite-difference time-domain method. Computational boundaries and parameters are set, electromagnetic field coefficients are calculated, and the electromagnetic field value is calculated using the central difference discretization equation. Absorption boundary conditions are applied, and the process is iterated until the final electromagnetic field value is output. The finite-difference time-domain method includes a set of time-domain advancement formulas, which are obtained by performing a difference discretization operation on the differential form of Maxwell's equations. In the formula, , , Rectangular grid edges , , Spatial interval of direction; It is a time interval; , , And n is an integer; If it is far-field interference, the interference propagation path is analyzed based on the spatial location of the interfering and affected devices: If it is a direct interference path, then the direct interference power is calculated according to the free space path loss model: In the formula, To receive the interference power at the front end of the equipment, for Transmit interference power at a given frequency This represents the gain of the transmitting antenna in the receiving direction. Let be the gain of the receiving antenna in the transmitting direction, where , Represents the horizontal azimuth angle of the antenna. , Represents the antenna elevation angle; For propagation path loss, where p is the spatial obstacle and medium characteristic parameter; If it is a reflection interference path, calculate the reflection coefficient based on the reflection point location, and finally calculate the reflected electromagnetic field strength; the formula for calculating the reflection coefficient is: in, and These are the reflection coefficients for vertically polarized waves and parallelly polarized waves, respectively. Given the angle of incidence, the complex permittivity of the medium. , Represents the imaginary part of a complex function, where Let be the relative permittivity of the incident medium. The relative permittivity of the ejection medium; It is the dielectric constant. It is the conductivity of the reflecting surface. It is the angular frequency; assuming S is a field point on the reflected ray at a distance s from the reflection point Q, then the final field of the reflected wave at field point S is: In the formula, , where is the diffusion factor, s' is the distance between the source point and the reflection point Q, and s is the distance between the reflection point Q and the field point; This represents the incident final wave field at reflection point Q. This represents the final wavefield at the receiving point S; Represents the reflection coefficient, which is divided into vertically polarized wave reflection coefficient. and parallel polarized wave reflection coefficient Two parts, The imaginary part of the complex function is represented by k, where k is the wave number. ; If it is a diffraction interference path, then calculate the diffraction coefficient based on the location of the diffraction point, and finally calculate the diffracted electromagnetic field strength; the formula for calculating the diffraction coefficient is: In the formula, The diffraction coefficient for vertically polarized waves. The diffraction coefficient for horizontally polarized waves; represents the imaginary part of the complex function; n is the wedge factor, which is 3 / 2 at a 90-degree bend; k is the wave number. It is the angle between the incident ray and the wedge; where, In the formula , For distance parameters, Let be the transition function, which is expressed as: in, The diffraction coefficient correlation function, , It is the angle between the incident wave at the diffraction point and the edge of the object. It is the angle between the diffracted wave at the diffraction point and the edge of the object. Represents the imaginary part of a complex function; It is the integer that is closest to satisfying the following equation: Let be the radius of curvature, for a right-angled wedge, the radius of curvature of the edge of the object diffracting. ,but ; Assuming P is an arbitrary point on the diffracted ray, and its distance from the diffracting point M is s, then the field strength at the diffracting point is: in, For the final field of the diffracted wave, This represents the final field of the incident wave at the diffraction point. The diffraction coefficient is divided into two categories. and Two parts; If it is a transmission interference path, calculate the transmission coefficient based on the transmission point location, and finally calculate the transmitted electromagnetic field intensity; vertical polarization transmission coefficient. and horizontal polarization transmission coefficient The calculation formula is: In the formula, Angle of incidence The angle of refraction is the transmission angle; when the medium is lossy, the angle of refraction is a complex number. , The refractive index of the incident medium is... Let be the refractive index of the transmission medium, where It is the propagation constant. , actual part It is the attenuation constant, imaginary part It is the phase constant; It is wave impedance. , It is the complex permittivity; The incident medium impedance, The impedance of the transmission medium; Assuming the total path distance of the ray before penetration at point Q is s, then the final field of the transmitted wave at point Q is... The final field of the incident wave at reflection point Q The relationship is: in, The incident wave transmission coefficient, The transmission coefficient of the outgoing wave. Let be the distance the ray travels in the medium. Represents the imaginary part of a complex function; Finally, the effective interference power is calculated based on the electromagnetic field strength, and the interference intensity is analyzed based on the interference margin.

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