VLF radiation efficiency calculation method

Abstract

The invention relates to the technical field of very low frequency communication, and discloses a VLF radiation efficiency calculation method, computer equipment, a computer readable storage medium and a computer program product in order to solve the problem of how to accurately measure the radiation efficiency of a very low frequency antenna. The method comprises the steps of performing simulation modeling on radiation characteristics of the lossless monopole antenna on the horizontal ground; comparing the electric field intensity obtained by simulation with the electric field intensity obtained by calculation through a ground wave propagation formula, and taking the electric field intensity obtained by simulation as a reference value of the standard electric field intensity under the condition that the electric field intensity obtained by simulation is consistent with the electric field intensity obtained by calculation through a ground wave propagation formula; simulation modeling is carried out on radiation characteristics of the very-low-frequency horizontal low-frame antenna, and vertical polarization radiation electric field intensity values generated at the same input power and the same position are calculated; and calculating the radiation efficiency of the very low frequency level low-frame antenna based on the vertical polarization radiation electric field intensity value and the reference value of the standard electric field intensity. By adopting the method, the measurement precision of the radiation efficiency of the very-low-frequency level low-frame antenna can be improved.

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 the transmission line are perfectly matched, Γ = 0; at this time, the reflection mismatch efficiency is 1. However, in engineering applications, the radiation efficiency of the antenna is more concerned.

[0004] In the IEEE145 standard, the antenna radiation efficiency is defined as the ratio of the antenna's radiation 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 power loss, 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 antennas are electrically small antennas with very small radiation resistance, generally only 10 -1 The reactance is about 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 work 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 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 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 the lossless monopole antenna on the horizontal ground are simulated and modeled, and the electric field strength at the input power of the preset transmitting antenna and the preset distance between the transmitting and receiving antennas is calculated;

[0012] The electric field strength obtained by simulation is compared with the electric field strength calculated by the ground wave propagation formula. When 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-rise antenna are simulated and modeled to calculate the vertical polarization radiation electric field strength value generated at the same input power and the same position;

[0014] Based on the vertical polarization radiation electric field strength value and the reference value of the standard electric field strength, the radiation efficiency of the very low frequency horizontal low-mounted antenna is calculated.

[0015] Further, based on the vertical polarization radiation electric field strength value and the reference value of the standard electric field strength, 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 strength value of the very low frequency horizontal low-mounted antenna to the reference value of the standard electric field strength.

[0016] Further, based on the vertical polarization radiation electric field strength value and the reference value of the standard electric field strength, the radiation efficiency of the very low frequency horizontal low-rise antenna is calculated, 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] In the formula, E z1 It represents 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 by the ground wave propagation formula, including:

[0022]

[0023] In the formula, 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] Wherein, 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; 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, there is also provided 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 of any one of the above methods.

[0030] According to a third aspect of the present invention, there is also provided a computer-readable storage medium on which a computer program is stored, and 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 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 VLF radiation efficiency calculation method, which belongs to a simulation analogy method and is similar to an actual measurement method of the radiation efficiency of a very low frequency horizontal low-mounted antenna. The antenna radiation efficiency calculated by simulation fits the actual radiation efficiency of the antenna and has high measurement accuracy. The measurement method is simple and reliable and can realize 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 drawings required for use in the embodiments will be briefly introduced below. 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 paying 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;

[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 purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain 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 can be combined with each other as long as they do not conflict with each other.

[0042] The terms "first", "second", "third", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0043] At present, the commonly used antenna radiation efficiency measurement methods mainly include the pattern integration method, the directivity / gain method, and the formula method. The following introduces these three antenna radiation efficiency measurement methods respectively.

[0044] 1. Directional Pattern Integration Method

[0045] The pattern integration method measures the antenna's pattern to obtain the radiation power intensity on the antenna's closed sphere surface, and then obtains the antenna's radiation efficiency through integral calculation. 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 carried out in a microwave darkroom.

[0046] However, the measurement system structure of the directional pattern integration method is complex and needs to be carried out in an expensive microwave darkroom, and 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 the antenna radiation efficiency by using the antenna gain ratio directivity. The antenna gain is measured using a standard gain horn antenna, and the directivity is calculated by integrating the far-field 3D pattern of the antenna radiation (or estimating the directivity by beam width). The calculation formula for 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 directivity of the antenna is obtained, the radiation efficiency of the antenna can be calculated by using the ratio of gain to directivity:

[0051]

[0052] However, the directivity / gain method also has the following defects: low measurement accuracy, poor repeatability, time-consuming test process and high requirements for hardware facilities; the measurement error mainly comes from the gain error of the standard gain horn antenna, the conventional system error of the antenna's full 3D radiation pattern measurement, the reflection of the microwave darkroom and the antenna RF cable, etc., 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-ideal conductive ground can be equivalent to a loop antenna, which radiates vertically polarized waves in the far zone. According to the reciprocity principle of electromagnetic fields, the vertical electric field generated by a horizontal dipole antenna on the ground in the far zone is equal to the electric field value along the horizontal dipole direction generated by a monopole antenna at the same position in the far zone. The horizontal electric field of the 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 with a certain length, assuming its current distribution is I and its length is L, its radiation 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-rise antenna refers to the radiation efficiency equivalent to a monopole antenna. From this definition, the radiation efficiency of a horizontal low-rise antenna can be deduced as:

[0063]

[0064] In the formula, 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, these three antenna radiation efficiency measurement methods all have defects. In order to solve the problem of how to accurately measure the radiation efficiency of a very low frequency antenna, the present invention provides a VLF radiation efficiency calculation method, which belongs to a simulation analogy method, similar to the actual measurement method of the radiation efficiency of a very low frequency horizontal low-rise antenna. The difference between this method and the actual measurement method is mainly that the data of the radiation electric field is a simulation value calculated by electromagnetic simulation software rather than a measured value.

[0067] like Figure 1 As shown, a VLF radiation efficiency calculation method is provided, which can be executed by a terminal or by a server communicating with the terminal through a network. The terminal can be, but is not limited to, various personal computers, laptops, smart phones, tablet computers, etc. The server can be an independent server, or a server cluster composed of multiple servers can be used. Taking the application of the method to a terminal as an example, the method 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 the input power of a preset transmitting antenna and the distance between preset transmitting and receiving antennas;

[0069] Step 102, comparing the electric field strength obtained by simulation with the electric field strength calculated by the ground wave propagation formula, and when the two are consistent, using the electric field strength obtained by simulation as a reference value of the standard electric field strength;

[0070] Step 103, simulation modeling is performed on the radiation characteristics of the very low frequency horizontal low-mounted antenna, and the vertical polarization radiation electric field intensity value generated at the same input power and the same position is calculated;

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

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

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

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

[0075] 1) If Figure 2 As shown, 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] The electric field strength data obtained by simulation is compared with the electric field strength data calculated by the ground wave propagation formula. If the two values ​​are consistent, the simulation model is considered to be true and effective, and the electric field strength value obtained by simulation 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 the figure, 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 strength value generated by the horizontal low-mounted antenna at the same input power (1000w) and the same position (near field 50km).

[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), the radiation efficiency of the horizontal low-rise antenna is calculated.

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

[0080]

[0081] In the formula, 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] Wherein, 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 is calculated by FEKO electromagnetic simulation software. The simulation results show that when the frequency is 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-rise 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-rise antenna is expressed as η r2 The radiation efficiency of a lossless monopole antenna on the horizontal ground is given by Sure According to formula (5), we can determine Right now And because η r2 =100%, therefore,

[0089]

[0090] Finally, the 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 simulation results of the radiation efficiency of antennas with different lengths are shown. 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 on the basis of 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 realize fast and high-precision measurement of very low frequency antenna radiation efficiency.

[0093] The present application also provides a computer device, whose internal structure diagram 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 covered on 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 those shown in the figure, or combine certain components, or have a different arrangement of components.

[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 on which a computer program is stored, and when the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented. 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 micro drive, and 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 the present application is not limited by the described order of actions, because according to the present 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 the present application.

[0099] In the above embodiments, the description of each embodiment has its own emphasis. 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 is only an exemplary embodiment of the present disclosure, and the scope of the present disclosure cannot be limited thereto. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure here, those skilled in the art will easily think of the implementation scheme of the present disclosure. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the technical field not recorded in the present disclosure. The description and examples are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0101] The technical features of the above embodiments may 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 only 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 protection scope of the present invention.

Claims

1. A method for calculating VLF radiation efficiency, characterized in that: include: The radiation characteristics of the lossless monopole antenna on the horizontal ground are simulated and modeled, and the electric field strength at the input power of the preset transmitting antenna and the preset distance between the transmitting and receiving antennas is calculated; The electric field strength obtained by simulation is compared with the electric field strength calculated by the ground wave propagation formula. When the two are consistent, the electric field strength obtained by simulation is used 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 vertical polarization radiation electric field strength value generated at the same input power and the same 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 strength value and the reference value of the standard electric field strength.

2. The method according to claim 1, characterized in that The step of calculating the radiation efficiency of the very low frequency horizontal low-rise antenna based on the vertical polarization radiation electric field strength value and the reference value of the standard electric field strength comprises: 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, characterized in that The step of calculating the radiation efficiency of the very low frequency horizontal low-rise antenna based on the vertical polarization radiation electric field strength value and the reference value of the standard electric field strength comprises: 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 In the formula, E z1 It represents 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, characterized in that The electric field strength of a lossless monopole antenna on the horizontal ground is calculated using the ground wave propagation formula, including: In the formula, 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 Wherein, 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, characterized in that 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-rise antenna include: The electromagnetic simulation software FEKO is used to simulate and model the radiation characteristics of the 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 invention 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 being executed by a processor.

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