A method for calculating the efficiency of VLF radiation

Abstract

The application relates to the technical field of very low frequency communication, and discloses a VLF radiation efficiency calculation method, a computer device, a computer readable storage medium and a computer program product, to solve the problem of how to accurately measure the radiation efficiency of a very low frequency antenna. The method comprises the following steps: simulating and modeling the radiation characteristics of a non-loss monopole antenna on a horizontal ground; comparing the simulated electric field intensity with the electric field intensity calculated through a ground wave propagation formula, taking the simulated electric field intensity as a reference value of the standard electric field intensity when the two are consistent; simulating and modeling the radiation characteristics of a very low frequency horizontal low-pole antenna, calculating the vertical polarization radiation electric field intensity value generated at the same input power and the same position; and calculating the radiation efficiency of the very low frequency horizontal low-pole antenna based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity. The method can improve the measurement accuracy of the radiation efficiency of the very low frequency horizontal low-pole antenna.

Description

Technical Field

[0001] The present application relates to the field of very low frequency communication technology, and more specifically, to a VLF radiation efficiency calculation method, a computer device, a computer-readable storage medium, and a computer program product. Background Art

[0002] Antennas always have losses, and antenna efficiency is an important parameter in antenna transmission systems. Antenna efficiency includes antenna total efficiency, reflection mismatch efficiency, and radiation efficiency.

[0003] The total efficiency of the antenna is the product of the reflection mismatch efficiency and the radiation efficiency of the antenna. The reflection mismatch efficiency of the antenna is η c =1-|Γ 2 , where Γ=(Z in -Z0) / (Z in +Z0), Γ is the voltage reflection coefficient of the antenna at the input port, Z in is the antenna input impedance, and Z0 is the characteristic impedance of the transmission line. When the antenna and transmission line are perfectly matched, Γ = 0; the reflection mismatch efficiency is 1. However, in engineering applications, the antenna's radiation efficiency is of greater concern.

[0004] In the IEEE145 standard, antenna radiation efficiency is defined as the ratio of the antenna's radiated power to the antenna's input power, that is:

[0005]

[0006] Among them, P r is the radiated power of the antenna, P in is the input power of the antenna, P l is the antenna loss power, R r is the antenna radiation resistance, R l is the antenna loss resistance. R l Usually includes antenna conduction loss, dielectric loss and inductive loss. In order to improve the radiation performance of the antenna, the antenna loss resistance should be minimized.

[0007] Very low frequency antenna is an electrically small antenna with a very small radiation resistance, generally only 10 -1 The order of magnitude is about 10, but its reactance is relatively large, generally around 10 2 to 10 3 As a result, the radiation efficiency of the very low frequency antenna is very low.

[0008] Since very low frequency antennas usually operate in complex environments that affect their functions, their radiation efficiency is difficult to optimize through simulation software. Therefore, how to accurately measure the radiation efficiency of very low frequency antennas is an important and challenging task. Summary of the Invention

[0009] In order to solve the problem of how to accurately measure the radiation efficiency of a very low frequency (VLF) antenna, the present invention provides a VLF radiation efficiency calculation method, a computer device, a computer-readable storage medium, and a computer program product, which can improve the measurement accuracy of the radiation efficiency of a very low frequency (VLF) horizontal low-rise antenna.

[0010] To achieve the above object, according to a first aspect of the present invention, a method for calculating VLF radiation efficiency is provided, the method comprising:

[0011] The radiation characteristics of a lossless monopole antenna on a horizontal ground are simulated and modeled, and the electric field strength is calculated at the input power of the preset transmitting antenna and the preset distance between the transmitting and receiving antennas.

[0012] The electric field strength obtained by simulation is compared with the electric field strength calculated by the ground wave propagation formula. If the two are consistent, the electric field strength obtained by simulation is used as a reference value of the standard electric field strength.

[0013] The radiation characteristics of the horizontal low-mounted antenna are simulated and modeled to calculate the vertically polarized radiation electric field intensity value generated at the same input power and the same position;

[0014] The radiation efficiency of the very low frequency horizontal low-mounted antenna is calculated based on the vertically polarized radiation electric field strength value and the reference value of the standard electric field strength.

[0015] Further, based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity, the radiation efficiency of the very low frequency horizontal low-mounted antenna is calculated, including that the radiation efficiency of the very low frequency horizontal low-mounted antenna is the square of the ratio of the vertical polarization radiation electric field intensity value of the very low frequency horizontal low-mounted antenna to the reference value of the standard electric field intensity.

[0016] Furthermore, the radiation efficiency of the very low frequency horizontal low-mounted antenna is calculated based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity, including:

[0017] according to Sure

[0018] Where η r1 Denotes the radiation efficiency of the VLF horizontal low-mounted antenna, η r2 represents the radiation efficiency of a lossless monopole antenna on the horizontal ground;

[0019] According to the radiated power of the monopole antenna Sure

[0020] Where, E z1 Indicates the vertical polarization radiation electric field strength value of the very low frequency horizontal low-mounted antenna, Ez2 represents the electric field strength of a lossless monopole antenna on the horizontal ground, η r2 =100%.

[0021] Furthermore, the electric field strength of the lossless monopole antenna on the horizontal ground is calculated using the ground wave propagation formula, including:

[0022]

[0023] Where, E z is the electric field strength, its unit is V / m, P r is the radiated power, its unit is W, its value can be measured by a power meter, d is the distance between the transmitting and receiving antennas, its unit is m, W N is the ground wave attenuation factor, which is calculated as follows:

[0024]

[0025] Among them, the Sommerfeld mathematical distance in the very low frequency band can be written as p = ε0dω 2 / 2v0σ, the ground conductivity and curvature coefficient are

[0026]

[0027] Where σ is the ground conductivity, which is 0.001s / m, a' is the equivalent radius of the Earth, which is 6371km, and β = 2π / λ is the propagation constant.

[0028] Furthermore, the radiation characteristics of the lossless monopole antenna on the horizontal ground and the radiation characteristics of the very low frequency horizontal low-mounted antenna are simulated and modeled, including using the electromagnetic simulation software FEKO to simulate and model the radiation characteristics of the lossless monopole antenna on the horizontal ground; and using the electromagnetic simulation software FEKO to simulate and model the radiation characteristics of the very low frequency horizontal low-mounted antenna.

[0029] According to a second aspect of the present invention, a computer device is provided, which includes a memory, a processor, and a computer program stored in the memory, and the processor executes the computer program to implement the steps of any one of the above methods.

[0030] According to a third aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0031] According to a fourth aspect of the present invention, there is also provided a computer program product, comprising a computer program, which implements the steps of any one of the above methods when executed by a processor.

[0032] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0033] The present invention provides a method for calculating VLF radiation efficiency. This method belongs to a simulation analogy method and is similar to the actual measurement method of the radiation efficiency of a very low frequency horizontal low-mounted antenna. The antenna radiation efficiency calculated by simulation matches the actual radiation efficiency of the antenna and has high measurement accuracy. This measurement method is simple and reliable and can achieve fast and high-precision measurement of the very low frequency antenna radiation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic diagram of a flow chart of a VLF radiation efficiency calculation method provided in an embodiment of the present application;

[0036] Figure 2 A simulation model of the lossless monopole antenna provided in an embodiment of the present application;

[0037] Figure 3 A simulation model of a horizontal low-mounted antenna provided in an embodiment of the present application;

[0038] Figure 4 The electric field strength value of the very low frequency transmitting antenna obtained by simulation using the VLF radiation efficiency calculation method provided in the embodiment of the present application and the electric field strength value of the very low frequency transmitting antenna obtained by actual measurement;

[0039] Figure 5 The radiation efficiency simulation results of antennas of different lengths provided in the embodiments of the present application are as follows;

[0040] Figure 6 A schematic diagram of the internal structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0042] The terms "first," "second," "third," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0043] Currently, the commonly used methods for measuring antenna radiation efficiency include the pattern integration method, the directivity / gain method, and the formula method. The following sections introduce these three methods.

[0044] 1. Pattern Integration Method

[0045] The pattern integration method measures the antenna's pattern to obtain the radiation power intensity on the surface of the antenna's closed sphere, and then calculates the antenna's radiation efficiency through integration. Specifically, this method first measures the electric field intensity of a series of discrete points on the far-field closed sphere with the antenna as the center, calculates the average value of the Poynting vector at each point, and then multiplies it by the corresponding area to obtain the radiation power on each small area on the sphere. Finally, the radiation power values ​​of each discrete point on the sphere are accumulated to obtain the antenna's radiation power. Use a power meter to measure the antenna's input power P in The ratio of radiated power to input power is the antenna radiation efficiency. This method is usually performed in a microwave darkroom.

[0046] However, the measurement system structure of the pattern integration method is complex and needs to be carried out in an expensive microwave darkroom. In addition, the accumulated system error is large. At the same time, this method takes a long time to complete a test, and the measurement results are not accurate and have poor repeatability.

[0047] 2. Directivity / Gain Method

[0048] The directivity / gain method measures antenna radiation efficiency by comparing the antenna's gain to its directivity. Using a standard-gain horn antenna to measure antenna gain, the directivity is calculated by integrating the antenna's far-field 3D radiation pattern (or estimating it based on beamwidth). The formula for calculating directivity, D, is as follows:

[0049]

[0050] in, It represents the radiation power density on a spherical surface in the far field of the antenna. The directivity of the antenna is generally measured in a standard microwave darkroom. After the antenna directivity is obtained, the ratio of gain to directivity can be used to calculate the radiation efficiency of the antenna:

[0051]

[0052] However, the directivity / gain method also has the following defects: low measurement accuracy, poor repeatability, time-consuming testing process and high hardware requirements; measurement errors mainly come from the gain error of the standard gain horn antenna, the conventional system error of the antenna's full 3D radiation pattern measurement, and reflections from the microwave darkroom and antenna RF cable, resulting in a measurement error of the radiation efficiency of the measured antenna of ±15% to ±28%.

[0053] 3. Formula method

[0054] According to electromagnetic field theory, a horizontal antenna on a non-ideally conductive ground surface is equivalent to a loop antenna, which radiates vertically polarized waves in the far field. Due to the reciprocity principle of electromagnetic fields, the vertical electric field generated by a horizontal dipole antenna on the ground in the far field is equal to the electric field along the horizontal dipole direction generated by a monopole antenna at the same location in the far field. The horizontal electric field of a monopole antenna can be calculated using the radio wave propagation formula and wavefront tilt theory. Therefore, the vertically polarized electric field strength of a horizontal dipole antenna on the ground can be expressed as:

[0055]

[0056] Where j is the imaginary unit, I is the current, d is the differential operator, l is the antenna length, r is the distance between the transmitting and receiving points, k0 is the electromagnetic wave propagation coefficient, λ is the wavelength, and W is the ground wave attenuation factor. σ is the earth's electrical conductivity, ω is the angular frequency, ε0 ​​is the dielectric constant of free space, ε r is the relative dielectric constant, It is the angle between the current direction of the horizontal antenna element and the line connecting the transmitting and receiving points.

[0057] For an antenna of a certain length, assuming its current distribution is I and its length is L, its radiated electric field intensity is:

[0058]

[0059] For a monopole antenna, the radiated power is:

[0060]

[0061] Based on the expression of the electric field radiated by the antenna, the radiation efficiency of the antenna can be analyzed.

[0062] The radiation efficiency of a horizontal low-mounted antenna refers to the radiation efficiency equivalent to a monopole antenna. From this definition, the radiation efficiency of a horizontal low-mounted antenna can be deduced as:

[0063]

[0064] Where R in is the input resistance of the horizontal low-rise antenna, I in is the input current.

[0065] It can be seen that the process of calculating the radiation efficiency of the horizontal low-rise antenna through this formula is more complicated, and it is also necessary to measure the input resistance R of the horizontal low-rise antenna. in and input current I in .

[0066] Therefore, all three antenna radiation efficiency measurement methods have flaws. To address the issue of how to accurately measure the radiation efficiency of very low frequency (VLF) antennas, the present invention provides a VLF radiation efficiency calculation method. This method is a simulation analogy method, similar to the actual measurement method for the radiation efficiency of very low frequency (VLF) horizontal low-rise antennas. The main difference between this method and the actual measurement method is that the radiated electric field data is simulated values ​​calculated using electromagnetic simulation software rather than actual measured values.

[0067] like Figure 1 As shown, a method for calculating VLF radiation efficiency is provided. This method can be executed by a terminal or a server communicating with the terminal via a network. The terminal can be, but is not limited to, various personal computers, laptops, smartphones, tablets, etc. The server can be a standalone server or a server cluster consisting of multiple servers. This method is illustrated using a terminal as an example and includes the following steps:

[0068] Step 101: Simulate and model the radiation characteristics of a lossless monopole antenna on a horizontal ground, and calculate the electric field strength at a preset input power of a transmitting antenna and a preset distance between transmitting and receiving antennas.

[0069] Step 102: Compare the electric field strength obtained by simulation with the electric field strength calculated using the ground wave propagation formula. If the two are consistent, use the electric field strength obtained by simulation as a reference value for the standard electric field strength.

[0070] Step 103: Simulate and model the radiation characteristics of the very low frequency horizontal low-mounted antenna to calculate the vertically polarized radiation electric field intensity value generated at the same input power and the same position;

[0071] Step 104 : Calculate the radiation efficiency of the very low frequency horizontal low-rise antenna based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity.

[0072] The above-mentioned VLF radiation efficiency calculation method is a simulation analogy method, which is similar to the actual measurement method of the radiation efficiency of very low frequency horizontal low-mounted antennas. The antenna radiation efficiency calculated by simulation is consistent with the actual radiation efficiency of the antenna and has high measurement accuracy. This measurement method is simple and reliable, and can achieve fast and high-precision measurement of very low frequency antenna radiation efficiency.

[0073] In one embodiment, the above-mentioned step 104 calculates the radiation efficiency of the very low frequency horizontal low-mounted antenna based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity, including that the radiation efficiency of the very low frequency horizontal low-mounted antenna is the square of the ratio of the vertical polarization radiation electric field intensity value of the very low frequency horizontal low-mounted antenna to the reference value of the standard electric field intensity.

[0074] In one embodiment, the steps for calculating the radiation efficiency of a horizontal low-rise antenna using a simulation analogy method are as follows:

[0075] 1) If Figure 2 As shown in the figure, the electromagnetic simulation software FEKO is used to simulate and model the radiation characteristics of the lossless monopole antenna on the horizontal ground. The ground is set as an ideal conductor, the antenna input is 1000w (i.e., the input power of the transmitting antenna), and a point of 50km in the near field (i.e., the distance between the transmitting and receiving antennas) is selected for calculation.

[0076] Compare the simulated electric field strength data with the electric field strength data calculated using the ground wave propagation formula. If the two values ​​are consistent, the simulation model is considered to be authentic and valid. The simulated electric field strength value can be used as a reference value for the standard electric field strength (i.e., the field strength value corresponding to 100% antenna radiation efficiency).

[0077] 2) If Figure 3 As shown in Figure 1, the electromagnetic simulation software FEKO is used to simulate and model the radiation characteristics of the horizontal low-mounted antenna. FEKO is used to calculate the vertically polarized radiation electric field intensity value generated by the horizontal low-mounted antenna at the same input power (1000W) and the same position (50km near field).

[0078] 3) Based on the vertical polarization radiation electric field strength value in step 2) and the reference value of the standard electric field strength in step 1), calculate the radiation efficiency of the horizontal low-rise antenna.

[0079] In step 1), the electric field strength of the lossless monopole antenna on the horizontal ground is calculated using the ground wave propagation formula. The calculation formula is as follows:

[0080]

[0081] Where, E z is the electric field strength, its unit is V / m, P ris the radiated power, its unit is W, its value can be measured by a power meter, d is the distance between the transmitting and receiving antennas, its unit is m, W N is the ground wave attenuation factor, which is calculated as follows:

[0082]

[0083] Among them, the Sommerfeld mathematical distance in the very low frequency band can be written as p = ε0dω 2 / 2v0σ, the ground conductivity and curvature coefficient are

[0084]

[0085] Where σ is the ground conductivity, which is 0.001s / m, a' is the equivalent radius of the Earth, which is 6371km, and β = 2π / λ is the propagation constant.

[0086] Figure 4 The electric field strength values ​​of the very low frequency transmitting antenna simulated using the VLF radiation efficiency calculation method (the blue discrete data points in the figure) and the electric field strength values ​​of the very low frequency transmitting antenna actually measured (the red continuous curve in the figure) are shown. Figure 4 As shown in the figure, the radiated electric field of an ideal lossless monopole antenna at 50km was calculated using FEKO electromagnetic simulation software. The simulation results show that at a frequency of 15kHz, the electric field strength at 50km is -41.4dBV / m, while the calculated result obtained according to the ground wave propagation formula is -41.5dBV / m, and the two are highly consistent.

[0087] In one embodiment, in step 3), based on the vertical polarization radiation electric field strength value (set as E z1 ) and the reference value of the standard electric field strength in step 1) (set as E z2 ), calculate the radiation efficiency of the horizontal low-mounted antenna. The steps are:

[0088] The electric field strength value of the lossless monopole antenna on the horizontal ground is calculated according to formula (7), and the reference value of the standard electric field strength E is obtained. z2 ; Use η r1 The radiation efficiency of the horizontal low-mounted antenna is expressed as η r2 The radiation efficiency of a lossless monopole antenna on the horizontal ground is calculated according to Sure According to formula (5), determine Right now And because η r2 =100%, therefore,

[0089]

[0090] Finally, E calculated by formula (7) z2 And step 2) the vertical polarization radiation electric field strength value of the horizontal low-rise antenna calculated by FEKO simulation (set as E z1 ) into formula (10), we can get the radiation efficiency of the horizontal low-rise antenna.

[0091] Figure 5 The figure shows the radiation efficiency simulation results of antennas with different lengths. It can be seen from the figure that the radiation efficiency of the VLF antenna calculated by the VLF radiation efficiency calculation method is reliable.

[0092] The above-mentioned VLF radiation efficiency calculation method is proposed based on the formula method. The antenna radiation efficiency calculated by simulation is consistent with the actual radiation efficiency of the antenna and has high measurement accuracy. This measurement method is simple and reliable and can achieve fast and high-precision measurement of very low frequency antenna radiation efficiency.

[0093] The present application also provides a computer device, the internal structure of which can be as follows: Figure 6 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a VLF radiation efficiency calculation method is implemented. The display unit of the computer device is used to form a visually visible image, and can be a display screen, a projection device or a virtual reality imaging device. The input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device casing, or an external keyboard, touchpad or mouse, etc.

[0094] Those skilled in the art will understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0095] like Figure 6 As shown, the present application also provides a computer device, which includes a memory, a processor and a computer program stored in the memory, and the processor executes the computer program to implement the steps in the above-mentioned method embodiments.

[0096] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned method embodiments. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a microdrive, a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0097] The present application also provides a computer program product, including a computer program, which implements the steps in the above-mentioned method embodiments when executed by a processor.

[0098] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0099] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0100] The above description is merely an exemplary embodiment of the present disclosure and is not intended to limit the scope of the present disclosure. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure herein, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary technical means in the art that are not recorded in the present disclosure. The description and examples are to be regarded as exemplary only, and the scope and spirit of the present disclosure are defined by the claims.

[0101] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, 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.

[0102] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for calculating VLF radiation efficiency, characterized in that: include: The radiation characteristics of a lossless monopole antenna on a horizontal ground are simulated and modeled, and the electric field strength is calculated at the input power of the preset transmitting antenna and the preset distance between the transmitting and receiving antennas. Comparing the electric field strength obtained by simulation with the electric field strength calculated using the ground wave propagation formula, and if the two are consistent, using the electric field strength obtained by simulation as a reference value of the standard electric field strength; The radiation characteristics of the very low frequency horizontal low-mounted antenna are simulated and modeled, and the vertically polarized radiation electric field strength generated at the same input power and position is calculated; The radiation efficiency of the very low frequency horizontal low-rise antenna is calculated based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity.

2. The method according to claim 1, wherein The calculating the radiation efficiency of the very low frequency horizontal low-mounted antenna based on the vertically polarized radiation electric field intensity value and the reference value of the standard electric field intensity includes: The radiation efficiency of the very low frequency horizontal low-mounted antenna is the square of the ratio of the vertically polarized radiation electric field strength value of the very low frequency horizontal low-mounted antenna to the reference value of the standard electric field strength.

3. The method according to claim 1, wherein The calculating the radiation efficiency of the very low frequency horizontal low-mounted antenna based on the vertically polarized radiation electric field intensity value and the reference value of the standard electric field intensity includes: according to Sure Where η r1 Denotes the radiation efficiency of the VLF horizontal low-mounted antenna, η r2 represents the radiation efficiency of a lossless monopole antenna on the horizontal ground; According to the radiated power of the monopole antenna Sure Where, E z1 Indicates the vertical polarization radiation electric field strength value of the very low frequency horizontal low-mounted antenna, E z2 represents the electric field strength of a lossless monopole antenna on the horizontal ground, η r2 =100%.

4. The method according to claim 1, wherein The electric field strength of a lossless monopole antenna on the horizontal ground is calculated using the ground wave propagation formula, including: Where, E z is the electric field strength, its unit is V / m, P r is the radiated power, its unit is W, its value can be measured by a power meter, d is the distance between the transmitting and receiving antennas, its unit is m, W N is the ground wave attenuation factor, which is calculated as follows: Among them, the Sommerfeld mathematical distance in the very low frequency band can be written as p = ε0dω 2 / 2v0σ, the ground conductivity and curvature coefficient are Where σ is the ground conductivity, which is 0.001s / m, a' is the equivalent radius of the Earth, which is 6371km, and β = 2π / λ is the propagation constant.

5. The method according to claim 1, wherein The simulation modeling of the radiation characteristics of the lossless monopole antenna on the horizontal ground and the simulation modeling of the radiation characteristics of the very low frequency horizontal low-mounted antenna include: The electromagnetic simulation software FEKO is used to simulate and model the radiation characteristics of a lossless monopole antenna on the horizontal ground. The electromagnetic simulation software FEKO is used to simulate and model the radiation characteristics of the very low frequency horizontal low-mounted antenna.

6. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method according to any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

8. A computer program product, characterized in that The invention comprises a computer program, which implements the steps of the method according to any one of claims 1 to 5 when the computer program is executed by a processor.

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