Method, device and equipment for calculating electromagnetic wave in ground-ionosphere waveguide and medium

Abstract

This invention discloses a method, apparatus, device, and medium for calculating electromagnetic waves in a geo-ionospheric waveguide. It obtains the pulse operating frequency set and medium parameter set of electromagnetic waves in a layered geo-ionospheric waveguide model. The electromagnetic waves consist of multiple electromagnetic waves to be calculated in different frequency bands. Based on the pulse operating frequency and medium parameter set of each electromagnetic wave to be calculated, a target calculation method for the receiving electric field is determined from multiple preset electric field calculation methods. The target transmission coefficient is determined based on the transmitting electric field at the emission point of each electromagnetic wave to be calculated, the layered geo-ionospheric waveguide model, and the target calculation method for the receiving electric field. The time-domain waveform of the electromagnetic waves is calculated based on the target transmission coefficients of multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula. In this way, the most suitable target calculation method for the receiving electric field is determined based on the pulse operating frequency set and medium parameter set of the electromagnetic waves to be calculated in different frequency bands, enabling accurate and rapid calculation of electromagnetic waves in a layered geo-ionospheric waveguide.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic calculation technology, and in particular to a method, apparatus, equipment and medium for calculating electromagnetic waves in an ionospheric waveguide. Background Technology

[0002] Radio electromagnetic waves (including artificially generated radio electromagnetic waves and electromagnetic pulses caused by lightning, nuclear explosions, earthquakes, etc.) have an extremely wide spectral range, covering from extremely low frequencies of a few hertz to ultra-high frequencies of hundreds of gigahertz, and can propagate hundreds or even thousands of kilometers along the Earth's surface. These waves can interfere with or even damage ground-based electronic equipment and systems through various coupling pathways. Currently, limited by the high cost, narrow detection range, and low detection efficiency of observation station experiments, the application and development of physical methods and technologies for radio electromagnetic waves have become essential for studying the propagation laws of broadband radio electromagnetic waves in the Earth-ionospheric waveguide. Developing related technologies to study the propagation characteristics of multi-band electromagnetic waves in the Earth-ionospheric waveguide has significant academic and applied value for fields such as lightning location and parameter inversion, ionospheric monitoring, and engineering protection against lightning electromagnetic pulses.

[0003] In existing technologies, methods for calculating the propagation of radio electromagnetic waves are mainly divided into analytical methods and numerical methods. Different methods are applicable to electromagnetic waves in different operating frequency bands and propagation environments. For example, waveguide mode theory is suitable for electromagnetic wave calculations in the very low frequency (VLF) band, while wave jump theory is suitable for VLF and low frequency bands. However, neither of these methods can accurately calculate electromagnetic waves in the very low frequency band. Fock's ground wave diffraction theory can be used for electromagnetic wave calculations from low to very high frequencies, but it is not suitable for VLF and VLF bands where the influence of the ionosphere needs to be considered. Uniform plane wave theory is not suitable for curved surface propagation scenarios or long-distance electromagnetic wave calculations. Therefore, existing technologies cannot accurately and quickly achieve electromagnetic wave calculations in layered ground-ionospheric waveguides. Summary of the Invention

[0004] The purpose of this invention is to provide a method, apparatus, device, and medium for calculating electromagnetic waves in a ground-ionospheric waveguide, which solves the problem that existing technologies cannot accurately and quickly calculate electromagnetic waves in layered ground-ionospheric waveguides.

[0005] To achieve the above objectives, in a first aspect, embodiments of the present invention provide a method for calculating electromagnetic waves in a ground-ionospheric waveguide, the method comprising: Obtain the pulse operating frequency set and medium parameter set of electromagnetic waves in a layered earth-ionospheric waveguide model; wherein, the electromagnetic waves consist of multiple electromagnetic waves to be calculated in different frequency bands, the pulse operating frequency set includes: pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands, and the medium parameter set includes: transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands. Based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands, the target calculation method for the received electric field is determined from multiple preset electric field calculation methods. Based on the transmitting electric field of the transmission point corresponding to the electromagnetic wave to be calculated in different frequency bands, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field, the target transmission coefficient of each electromagnetic wave to be calculated is determined. The time-domain waveform of the electromagnetic wave is calculated based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

[0006] In one embodiment, determining the target electric field calculation method from multiple preset electric field calculation methods based on the pulse operating frequency corresponding to the electromagnetic wave to be calculated in each different frequency band and the dielectric parameter set includes: Based on the pulse operating frequency corresponding to the electromagnetic wave to be calculated in different frequency bands, multiple initial calculation methods for the received electric field are determined from multiple preset electric field calculation methods. Based on the transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters, among multiple initial calculation methods for the received electric field, a target calculation method for the received electric field is determined. The preset electric field calculation method includes: numerical calculation method, waveguide mode theory calculation method, wave jump theory calculation method, Fock ground wave diffraction theory calculation method, and uniform flat ground theory calculation method.

[0007] In one embodiment, before obtaining the pulse operating frequency set and dielectric parameter set of electromagnetic waves in the layered earth-ionospheric waveguide model, the method further includes: A layered ground-ionospheric waveguide model is constructed, wherein the layered ground-ionospheric waveguide model includes: an ionospheric electron density index model, an ionospheric collision frequency model, dielectric parameters of the layered ground, and an electric dipole moment.

[0008] In one embodiment, determining the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmission point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method for the receiving electric field includes: Based on the target calculation method for the received electric field, the electron density index model of the ionosphere, the collision frequency model of the ionosphere, the dielectric parameters of the layered ground, and the electric dipole moment, the received electric field of each electromagnetic wave to be calculated is determined. The target transmission coefficient of each electromagnetic wave to be calculated is determined based on the received electric field and the transmitted electric field of the electromagnetic waves to be calculated in different frequency bands.

[0009] In one embodiment, determining the target transmission coefficient of each electromagnetic wave to be calculated based on the received electric field and the transmitted electric field of the electromagnetic waves to be calculated in different frequency bands includes: For electromagnetic waves to be calculated in different frequency bands, the received electric field containing the received amplitude and received phase is divided by the transmitted electric field containing the transmitted amplitude and transmitted phase to obtain the target transmission coefficient of each electromagnetic wave to be calculated.

[0010] In one embodiment, calculating the time-domain waveform of the electromagnetic wave based on multiple target transmission coefficients of the electromagnetic waves to be calculated and a preset electromagnetic pulse frequency-domain calculation formula includes: Based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula, the frequency domain data of the electromagnetic waves are obtained. Perform an inverse Fourier transform on the frequency domain data to obtain the time domain waveform of the electromagnetic wave.

[0011] In one embodiment, obtaining the frequency domain data of the electromagnetic wave based on multiple target transmission coefficients of the electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula includes: After connecting the target transmission coefficients according to the different frequency bands corresponding to the multiple electromagnetic waves to be calculated, the coefficients are multiplied by the preset electromagnetic pulse frequency domain calculation formula to obtain the frequency domain data of the electromagnetic waves.

[0012] In a second aspect, embodiments of the present invention provide an electromagnetic wave calculation device in an earth-ionospheric waveguide, the device comprising: The acquisition module is used to acquire the pulse operating frequency set and the medium parameter set of electromagnetic waves in the layered earth-ionospheric waveguide model; wherein, the electromagnetic waves are composed of multiple electromagnetic waves to be calculated in different frequency bands, the pulse operating frequency set includes: pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands respectively, and the medium parameter set includes: transmission distance, multi-layer flat and curved ground parameters and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands respectively; The receiving electric field target calculation method determination module is used to determine the receiving electric field target calculation method from multiple preset electric field calculation methods based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands. The target transmission coefficient determination module is used to determine the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmitting point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field. The time-domain waveform calculation module is used to calculate the time-domain waveform of the electromagnetic wave based on the target transmission coefficients of multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula.

[0013] Thirdly, embodiments of the present invention provide an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the electromagnetic wave calculation method in the earth-ionospheric waveguide described in the first aspect.

[0014] Fourthly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the electromagnetic wave calculation method in the earth-ionospheric waveguide described in the first aspect.

[0015] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art: This invention provides a method for calculating electromagnetic waves in a geo-ionospheric waveguide. First, it obtains the pulse operating frequency set and medium parameter set of the electromagnetic waves in a layered geo-ionospheric waveguide model. The electromagnetic waves consist of multiple electromagnetic waves of different frequency bands to be calculated. The pulse operating frequency set includes the pulse operating frequencies corresponding to the multiple electromagnetic waves of different frequency bands. The medium parameter set includes the transmission distance, multi-layered curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves of different frequency bands. Then, based on the pulse operating frequencies and medium parameter sets corresponding to the electromagnetic waves of different frequency bands, a target calculation method for the receiving electric field is determined from multiple preset electric field calculation methods. Further, based on the transmitting electric field at the transmission point corresponding to the electromagnetic waves of different frequency bands, the layered geo-ionospheric waveguide model, and the target calculation method for the receiving electric field, the target transmission coefficient of each electromagnetic wave to be calculated is determined. Finally, based on the target transmission coefficients of the multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula, the time-domain waveform of the electromagnetic waves is calculated. In this way, for electromagnetic waves of different frequency bands to be calculated, the most suitable receiving electric field target calculation method for each electromagnetic wave to be calculated is determined by the corresponding pulse operating frequency set and medium parameter set. This method can accurately and quickly realize electromagnetic wave calculation in the layered ground-ionospheric waveguide model. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 A flowchart illustrating a method for calculating electromagnetic waves in an ionospheric waveguide, provided by an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the field strength amplitude and phase of an electromagnetic wave to be calculated, provided as an embodiment of the present invention. Figure 3 This is a schematic diagram of an electromagnetic wave calculation device in an ionospheric waveguide provided in an embodiment of the present invention. Detailed Implementation

[0017] To facilitate a clear description of the technical solutions in the embodiments of the present invention, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. For example, the first threshold and the second threshold are merely used to distinguish different thresholds and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" are not necessarily different.

[0018] It should be noted that in this invention, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0019] In this invention, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between the associated objects, indicating that three relationships can exist.

[0020] like Figure 1 As shown, Figure 1 This is a flowchart illustrating a method for calculating electromagnetic waves in an ionospheric waveguide according to an embodiment of the present invention, specifically including the following steps: S10: Obtain the pulse operating frequency set and dielectric parameter set of electromagnetic waves in the layered ground-ionospheric waveguide model.

[0021] The electromagnetic waves consist of multiple electromagnetic waves of different frequency bands to be calculated, including: extremely low frequency (ULF), ultra-low frequency (ULF), extra-low frequency (ELF), very low frequency (VLF), low frequency (LHF), medium frequency (IF), high frequency (HF), very high frequency (VHF), and microwave. The pulse operating frequency set includes the pulse operating frequencies corresponding to the electromagnetic waves of different frequency bands. For example, the pulse operating frequency corresponding to ULF is 500 Hz-3 kHz, the pulse operating frequency corresponding to VLF is 3 kHz-30 kHz, the pulse operating frequency corresponding to LHF is 30 kHz-70 kHz, the pulse operating frequency corresponding to IF is 300 kHz-3 MHz, and the pulse operating frequency corresponding to HF is 3 MHz-13 MHz. However, this is not a limitation; the present invention does not impose specific limitations, and those skilled in the art can determine the appropriate frequency based on the actual situation.

[0022] The aforementioned set of medium parameters includes: transmission distances corresponding to multiple electromagnetic waves to be calculated in different frequency bands, multi-layered flat and curved ground parameters, and ionospheric parameters. The multi-layered flat and curved ground parameters include: layering parameters, Earth surface curvature parameters, plane parameters, flat and curved surface parameters, and the rate of change of topography and ionosphere with time and space, but are not limited thereto. This invention does not impose specific limitations, and those skilled in the art can determine them according to the actual situation.

[0023] Specifically, the pulse operating frequency set and medium parameter set of electromagnetic waves propagating in the layered ground-ionospheric waveguide model are obtained. Since the electromagnetic waves are composed of multiple electromagnetic waves to be calculated in different frequency bands, the pulse operating frequencies and medium parameter sets corresponding to multiple electromagnetic waves to be calculated in different frequency bands, such as extremely low frequency, ultra-low frequency, extra-low frequency, very low frequency, low frequency, medium frequency, high frequency, very high frequency and microwave, are obtained respectively. Each medium parameter set includes: transmission distance, multi-layer flat and curved ground parameters and ionospheric parameters.

[0024] Optionally, based on the above embodiments, in some embodiments of the present invention, the method further includes the following before performing S12: Construct a layered ground-ionospheric waveguide model.

[0025] The layered ground-ionospheric waveguide model includes: the ionospheric electron density index model, the ionospheric collision frequency model, the dielectric parameters of the layered ground, and the electric dipole moment. These parameters are used to calculate the target transmission coefficient based on the pulse operating frequency of the electromagnetic wave to be calculated in each different frequency band and the set of dielectric parameters. The dielectric parameters of the layered ground can be, for example, the relative permittivity, conductivity, and thickness of each layer.

[0026] Specifically, based on the International Reference Ionosphere (IRI), electron density index, or Nequick model, a layered ground-ionospheric waveguide model is constructed. The layered ground-ionospheric waveguide model includes at least the following: ionospheric model, electron density index model, ionospheric collision frequency model, and electric dipole moment.

[0027] Optionally, based on the above embodiments, in some embodiments of the present invention, the electric dipole moment may be defined by the following expression:

[0028] in, W indicates power, W =1 kW, Indicates vacuum wave impedance, , Indicates the operating frequency.

[0029] The electron density exponent model of the ionosphere can be defined by the following expression:

[0030] The ionospheric collision frequency model can be defined by the following expression:

[0031] in, h Indicates the altitude above the Earth in the Earth-ionosphere; H The reference height of the lower ionosphere above the ground is represented by β, which represents the gradient parameter describing the change of electron concentration with altitude.

[0032] S11: Based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands, determine the target calculation method for the received electric field from multiple preset electric field calculation methods.

[0033] The preset electric field calculation methods include: numerical calculation method, waveguide mode theory calculation method, wave jump theory calculation method, Fock ground wave diffraction theory calculation method, and uniform flat ground theory calculation method. The target calculation method for the receiving electric field is used to calculate the receiving electric field corresponding to the electromagnetic wave of different frequency bands at the receiving point.

[0034] For example, the wave jump theory calculation method can be defined by the following expression:

[0035] in, Indicates the transmission power. Indicates the first The electric field of the sky wave.

[0036] For example, when When = 0, the electric field of the 0th order sky wave can be defined by the following expression:

[0037] in, Represents the propagation constant of the electromagnetic wave to be calculated in free space. W Indicates the ground wave attenuation factor. d This represents the great circle distance between the transmitting and receiving points corresponding to the electromagnetic wave to be calculated.

[0038] Another example is when When = 4, the electric field of the fourth-order sky wave can be defined by the following expression:

[0039] in, This represents the total length of the rays in the fourth-order sky wave; This indicates the angle of departure and angle of arrival of the 4th-order sky wave on the ground; D This represents the convergence coefficient caused by the curvature of the ionosphere. This represents the divergence coefficient caused by the curvature of the ground; This represents the background factor of the emission point due to the curvature and limited conductivity of the ground. This represents the background factor of the antenna at the receiving point due to the curvature and limited conductivity of the ground. , , and This represents the ionospheric reflection coefficient, where the first subscript indicates the polarization of the incident wave and the second subscript indicates the polarization of the reflected wave. and This represents the ground reflection coefficient.

[0040] Another exemplary method for calculating Fock's ground wave diffraction theory can be defined by the following expression:

[0041] in, This represents the electric moment of the electric dipole corresponding to the electromagnetic wave to be calculated; This represents the operating wavelength of the electromagnetic wave to be calculated; Indicates the wave impedance of air; Indicates the Earth's radius; k The air propagation constant; This represents the angular distance between the electromagnetic wave transmitter and receiver points to be calculated. V This represents the ground wave diffraction attenuation factor of the layered ground.

[0042] Specifically, for electromagnetic waves to be calculated in different frequency bands, the target calculation method for the receiving electric field of the electromagnetic waves to be calculated in different frequency bands is determined from multiple preset electric field calculation methods based on the corresponding pulse operating frequency and the medium parameter set.

[0043] Optionally, based on the above embodiments, in some embodiments of the present invention, one implementation of S11 may be: S111: Based on the pulse operating frequency corresponding to the electromagnetic wave to be calculated in different frequency bands, determine multiple initial calculation methods for the received electric field from multiple preset electric field calculation methods.

[0044] Specifically, for electromagnetic waves to be calculated in different frequency bands, based on their corresponding pulse operating frequencies, multiple initial calculation methods for the received electric fields of electromagnetic waves to be calculated in different frequency bands are determined from multiple preset electric field calculation methods.

[0045] For example, for very low frequency electromagnetic waves to be calculated, based on the corresponding pulse operating frequency of 3 kHz-30 kHz, multiple initial calculation methods for the received electric field are determined using various preset electric field calculation methods, such as numerical calculation methods, waveguide mode theory calculation methods, wave jump theory calculation methods, Fock ground wave diffraction theory calculation methods, and uniform flat ground theory calculation methods. However, this invention is not limited to these methods; those skilled in the art can determine the appropriate method based on the actual situation.

[0046] Another example is that, for low-frequency electromagnetic waves to be calculated, based on the corresponding pulse operating frequency of 30 kHz-70 kHz, multiple initial calculation methods for the received electric field are determined using multiple preset electric field calculation methods, such as numerical calculation methods, waveguide mode theory calculation methods, wave jump theory calculation methods, Fock ground wave diffraction theory calculation methods, and uniform flat ground theory calculation methods. However, this invention is not limited to these methods and can be determined by those skilled in the art based on the actual situation.

[0047] S112: Based on the transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters, determine the target calculation method for the received electric field among multiple initial calculation methods for the received electric field.

[0048] Specifically, after obtaining multiple initial calculation methods for the received electric field corresponding to the electromagnetic waves to be calculated in different frequency bands, the target calculation method for the received electric field corresponding to the electromagnetic waves to be calculated in different frequency bands is determined from among the multiple initial calculation methods for the received electric field.

[0049] For example, following the above embodiments, for very low frequency electromagnetic waves to be calculated, among multiple initial calculation methods for the received electric field, such as numerical calculation methods, waveguide mode theory calculation methods, and wave jumping theory calculation methods, when calculation speed or transmission speed is required, waveguide mode theory calculation methods and wave jumping theory calculation methods are selected. Furthermore, if ionospheric parameters need to be considered simultaneously, such as the spatiotemporal changes in terrain and ionosphere every 100km interval, waveguide mode theory is selected between waveguide mode theory calculation methods and wave jumping theory calculation methods. However, this invention is not limited thereto, and those skilled in the art can determine the appropriate method based on the actual situation.

[0050] Another example is that, for low-frequency electromagnetic waves to be calculated, multiple methods for initial calculation of the received electric field are available, such as numerical calculation methods, wave jump theory calculation methods, Fock ground wave diffraction theory calculation methods, and uniform flat ground theory calculation methods. When calculation speed and distance are required, the wave jump theory calculation method or the Fock ground wave diffraction theory calculation method is selected from among these methods. Furthermore, when ionospheric parameters, such as the size of the layered ground-ionospheric waveguide model, are required, the numerical calculation method is determined. However, this invention is not limited to these methods; those skilled in the art can determine the appropriate method based on the actual situation.

[0051] S12: Determine the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmitting point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field.

[0052] Specifically, after obtaining the target calculation method for the receiving electric field of the electromagnetic wave to be calculated in each different frequency band, the target transmission coefficient of each electromagnetic wave to be calculated is determined based on the transmitting electric field of the transmitting point, the layered ground-ionospheric waveguide model, and the target calculation method for the receiving electric field of the electromagnetic wave to be calculated in each different frequency band.

[0053] Optionally, based on the above embodiments, in some embodiments of the present invention, S12 may be implemented as follows: S120: Determine the received electric field of each electromagnetic wave to be calculated based on the target calculation method of the received electric field, the electron density index model of the ionosphere, the collision frequency model of the ionosphere, and the electric dipole moment.

[0054] The received electric field consists of the received amplitude and the received phase.

[0055] Specifically, for electromagnetic waves to be calculated in different frequency bands, the electron density index model of the ionosphere, the collision frequency model of the ionosphere, and the electric dipole moment are substituted into the calculation method of the receiving electric field target to calculate the receiving electric field of each electromagnetic wave to be calculated.

[0056] The received electric field consists of the received amplitude and the received phase. For example, following the above embodiment, refer to... Figure 2 As shown, for low-frequency electromagnetic waves to be calculated, the received amplitude and phase of the received electric field corresponding to the low-frequency electromagnetic waves to be calculated are determined by the target calculation method of the received electric field, such as the wave jump theory calculation method.

[0057] S121: Determine the target transmission coefficient of each electromagnetic wave to be calculated based on the received electric field and the transmitted electric field of the electromagnetic waves to be calculated in different frequency bands.

[0058] Specifically, after obtaining the received electric field of the electromagnetic wave to be calculated in each different frequency band, the corresponding transmitted electric field of the electromagnetic wave to be calculated in each different frequency band at the transmission point is obtained. Based on the received electric field and transmitted electric field of the electromagnetic wave to be calculated in each different frequency band, the target transmission coefficient of each electromagnetic wave to be calculated is determined.

[0059] Optionally, based on the above embodiments, the receiving electric field consists of the receiving amplitude and the receiving phase, and the transmitting electric field consists of the transmitting amplitude and the transmitting phase. Therefore, in some embodiments of the present invention, one implementation of S121 may be: S1211: For electromagnetic waves to be calculated in different frequency bands, the received electric field containing the received amplitude and received phase is divided by the transmitted electric field containing the transmitted amplitude and transmitted phase to obtain the target transmission coefficient of each electromagnetic wave to be calculated.

[0060] Specifically, the received amplitude and phase of the received electric field, and the transmitted amplitude and phase of the transmitted electric field are determined. The received electric field containing the received amplitude and phase is divided by the transmitted electric field containing the transmitted amplitude and phase to obtain the target transmission coefficient of each electromagnetic wave to be calculated.

[0061] S13: Calculate the time-domain waveform of the electromagnetic wave based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

[0062] Optionally, based on the above embodiments, in some embodiments of the present invention, one implementation of S13 may be: S131: Obtain the frequency domain data of electromagnetic waves based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

[0063] Specifically, after obtaining the target transmission coefficients corresponding to multiple electromagnetic waves to be calculated, the frequency domain data of the electromagnetic waves are obtained based on the target transmission coefficients corresponding to the multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

[0064] Optionally, based on the above embodiments, in some embodiments of the present invention, one implementation of S131 may be: S1311: After connecting the target transmission coefficients according to the different frequency bands corresponding to the multiple electromagnetic waves to be calculated, multiply them with the preset electromagnetic pulse frequency domain calculation formula to obtain the frequency domain data of the electromagnetic waves.

[0065] Optionally, based on the above embodiments, in some embodiments of the present invention, the preset electromagnetic pulse frequency domain calculation formula is a preset double exponential pulse frequency domain calculation formula, which can be limited by the following expression:

[0066] in, , as well as It is a coefficient related to the pulse spectrum waveform. , , .

[0067] S132: Perform an inverse Fourier transform on the frequency domain data to obtain the time domain waveform of the electromagnetic wave.

[0068] Specifically, the target transmission coefficients corresponding to multiple electromagnetic waves of different frequency bands are concatenated according to their magnitude, and then multiplied by a preset electromagnetic pulse frequency domain calculation formula to obtain the frequency domain data of the electromagnetic wave. Finally, an inverse Fourier transform is performed on the frequency domain data to obtain the time domain waveform of the electromagnetic wave.

[0069] Thus, the electromagnetic wave calculation method in the Earth-ionospheric waveguide provided in this embodiment first obtains the pulse operating frequency set and the medium parameter set of the electromagnetic wave in the layered Earth-ionospheric waveguide model. The electromagnetic wave consists of multiple electromagnetic waves to be calculated in different frequency bands. The pulse operating frequency set includes the pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands, and the medium parameter set includes the transmission distance, multi-layered flat-curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands. Then, based on the pulse operating frequencies and medium parameter sets corresponding to the electromagnetic waves to be calculated in each different frequency band, a target calculation method for the receiving electric field is determined from multiple preset electric field calculation methods. Further, based on the transmitting electric field of the transmitting point corresponding to the electromagnetic waves to be calculated in each different frequency band, the layered Earth-ionospheric waveguide model, and the target calculation method for the receiving electric field, the target transmission coefficient of each electromagnetic wave to be calculated is determined. Finally, based on the target transmission coefficients of the multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula, the time-domain waveform of the electromagnetic wave is calculated. In this way, for electromagnetic waves of different frequency bands to be calculated, the most suitable receiving electric field target calculation method for each electromagnetic wave to be calculated is determined by the corresponding pulse operating frequency set and medium parameter set. This method can accurately and quickly realize electromagnetic wave calculation in the layered ground-ionospheric waveguide model.

[0070] It should be understood that, although Figure 1 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but may be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0071] In one embodiment, such as Figure 3 As shown, Figure 3 This is a schematic diagram of an electromagnetic wave calculation device in an ionospheric waveguide provided by an embodiment of the present invention, including: an acquisition module 10, a receiving electric field target calculation method determination module 11, a target transmission coefficient determination module 12, and a time-domain waveform calculation module 13.

[0072] The acquisition module 10 is used to acquire the pulse operating frequency set and the medium parameter set of electromagnetic waves in the layered earth-ionospheric waveguide model. The electromagnetic waves consist of multiple electromagnetic waves to be calculated in different frequency bands. The pulse operating frequency set includes the pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands. The medium parameter set includes the transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands.

[0073] The receiving electric field target calculation method determination module 11 is used to determine the receiving electric field target calculation method from multiple preset electric field calculation methods based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands.

[0074] The target transmission coefficient determination module 12 is used to determine the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmitting point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field.

[0075] The time-domain waveform calculation module 13 is used to calculate the time-domain waveform of electromagnetic waves based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

[0076] Thus, the electromagnetic wave calculation device in the Earth-ionospheric waveguide provided in this embodiment first uses an acquisition module to acquire the pulse operating frequency set and medium parameter set of electromagnetic waves in the layered Earth-ionospheric waveguide model. The electromagnetic waves consist of multiple electromagnetic waves to be calculated in different frequency bands. The pulse operating frequency set includes the pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands, and the medium parameter set includes the transmission distance, multi-layered flat-curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands. Then, the receiving electric field target calculation method determination module determines the receiving electric field target calculation method from multiple preset electric field calculation methods based on the pulse operating frequencies corresponding to the electromagnetic waves to be calculated in each different frequency band and the medium parameter set. Further, the target transmission coefficient determination module determines the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmitting point corresponding to the electromagnetic waves to be calculated in each different frequency band, the layered Earth-ionospheric waveguide model, and the receiving electric field target calculation method. Finally, the time-domain waveform calculation module calculates the time-domain waveform of the electromagnetic waves based on the target transmission coefficients of the multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency-domain calculation formula. In this way, for electromagnetic waves of different frequency bands to be calculated, the most suitable receiving electric field target calculation method for each electromagnetic wave to be calculated is determined by the corresponding pulse operating frequency set and medium parameter set. This method can accurately and quickly realize electromagnetic wave calculation in the layered ground-ionospheric waveguide model.

[0077] Specific limitations regarding the electromagnetic wave calculation device in the ionospheric waveguide can be found in the limitations of the electromagnetic wave calculation method in the ionospheric waveguide above, and will not be repeated here. The various modules in the aforementioned server can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independent of the processor in the computer device, or stored in software in the memory of the computer device, so that the processor can call and execute the corresponding operations of each module.

[0078] This invention provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it can implement the electromagnetic wave calculation method in an ionospheric waveguide provided by this invention. For example, when the processor executes the computer program, it can implement... Figure 1 The technical solutions of the method embodiments shown are similar in principle and in effect, and will not be described again here.

[0079] This invention provides a computer-readable storage medium storing at least one program, which is executed by a processor to implement... Figure 1 The technical solutions of the method embodiments shown are similar in principle and in effect, and will not be described again here.

[0080] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, databases, or other media used in the embodiments provided by this invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static random access memory (SRAM) and dynamic random access memory (DRAM), etc.

[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for calculating electromagnetic waves in a ground-ionospheric waveguide, characterized in that, The method includes: Obtain the pulse operating frequency set and medium parameter set of electromagnetic waves in a layered earth-ionospheric waveguide model; wherein, the electromagnetic waves consist of multiple electromagnetic waves to be calculated in different frequency bands, the pulse operating frequency set includes: pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands, and the medium parameter set includes: transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands. Based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands, the target calculation method for the received electric field is determined from multiple preset electric field calculation methods. Based on the transmitting electric field of the transmission point corresponding to the electromagnetic wave to be calculated in different frequency bands, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field, the target transmission coefficient of each electromagnetic wave to be calculated is determined. The time-domain waveform of the electromagnetic wave is calculated based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula.

2. The method according to claim 1, characterized in that, The step of determining the target electric field calculation method from multiple preset electric field calculation methods based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands includes: Based on the pulse operating frequency corresponding to the electromagnetic wave to be calculated in different frequency bands, multiple initial calculation methods for the received electric field are determined from multiple preset electric field calculation methods. Based on the transmission distance, multi-layer flat and curved ground parameters, and ionospheric parameters, among multiple initial calculation methods for the received electric field, a target calculation method for the received electric field is determined. The preset electric field calculation method includes: numerical calculation method, waveguide mode theory calculation method, wave jump theory calculation method, Fock ground wave diffraction theory calculation method, and uniform flat ground theory calculation method.

3. The method according to claim 1, characterized in that, Before obtaining the pulse operating frequency set and dielectric parameter set of electromagnetic waves in the layered ground-ionospheric waveguide model, the process also includes: A layered ground-ionospheric waveguide model is constructed, wherein the layered ground-ionospheric waveguide model includes: an ionospheric electron density index model, an ionospheric collision frequency model, dielectric parameters of the layered ground, and an electric dipole moment.

4. The method according to claim 3, characterized in that, The method for determining the target transmission coefficient of each electromagnetic wave to be calculated, based on the transmitting electric field of the transmission point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method for the receiving electric field, includes: Based on the target calculation method for the received electric field, the electron density index model of the ionosphere, the collision frequency model of the ionosphere, the dielectric parameters of the layered ground, and the electric dipole moment, the received electric field of each electromagnetic wave to be calculated is determined. The target transmission coefficient of each electromagnetic wave to be calculated is determined based on the received electric field and the transmitted electric field of the electromagnetic waves to be calculated in different frequency bands.

5. The method according to claim 4, characterized in that, The process of determining the target transmission coefficient of each electromagnetic wave to be calculated based on the received electric field and the transmitted electric field of the electromagnetic waves to be calculated in different frequency bands includes: For electromagnetic waves to be calculated in different frequency bands, the received electric field containing the received amplitude and received phase is divided by the transmitted electric field containing the transmitted amplitude and transmitted phase to obtain the target transmission coefficient of each electromagnetic wave to be calculated.

6. The method according to claim 5, characterized in that, The step of calculating the time-domain waveform of the electromagnetic wave based on the target transmission coefficients of multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula includes: Based on the target transmission coefficients of multiple electromagnetic waves to be calculated and the preset electromagnetic pulse frequency domain calculation formula, the frequency domain data of the electromagnetic waves are obtained. Perform an inverse Fourier transform on the frequency domain data to obtain the time domain waveform of the electromagnetic wave.

7. The method according to claim 6, characterized in that, The step of obtaining the frequency domain data of the electromagnetic waves based on the target transmission coefficients of multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula includes: After connecting the target transmission coefficients according to the different frequency bands corresponding to the multiple electromagnetic waves to be calculated, the coefficients are multiplied by the preset electromagnetic pulse frequency domain calculation formula to obtain the frequency domain data of the electromagnetic waves.

8. An electromagnetic wave calculation device in an ionospheric waveguide, characterized in that, The device includes: The acquisition module is used to acquire the pulse operating frequency set and the medium parameter set of electromagnetic waves in the layered earth-ionospheric waveguide model; wherein, the electromagnetic waves are composed of multiple electromagnetic waves to be calculated in different frequency bands, the pulse operating frequency set includes: pulse operating frequencies corresponding to the multiple electromagnetic waves to be calculated in different frequency bands respectively, and the medium parameter set includes: transmission distance, multi-layer flat and curved ground parameters and ionospheric parameters corresponding to the multiple electromagnetic waves to be calculated in different frequency bands respectively; The receiving electric field target calculation method determination module is used to determine the receiving electric field target calculation method from multiple preset electric field calculation methods based on the pulse operating frequency and medium parameter set corresponding to the electromagnetic waves to be calculated in different frequency bands. The target transmission coefficient determination module is used to determine the target transmission coefficient of each electromagnetic wave to be calculated based on the transmitting electric field of the transmitting point corresponding to the electromagnetic wave to be calculated in each different frequency band, the layered ground-ionospheric waveguide model, and the target calculation method of the receiving electric field. The time-domain waveform calculation module is used to calculate the time-domain waveform of the electromagnetic wave based on the target transmission coefficients of multiple electromagnetic waves to be calculated and a preset electromagnetic pulse frequency domain calculation formula.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the electromagnetic wave calculation method in the earth-ionospheric waveguide according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the electromagnetic wave calculation method in the earth-ionospheric waveguide according to any one of claims 1 to 7.

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