A method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals

Abstract

The present application belongs to the technical field of ground-to-space frequency-domain electromagnetic signal analysis, and relates to a method for estimating parameters of the magnetic transfer function of ground-to-space frequency-domain electromagnetic signals, comprising: performing noise suppression on the original signal voltage collected by a magnetometer to obtain a compensated signal voltage; filtering the emission current to obtain a filtered voltage signal; synchronously extracting and transforming the compensated signal voltage and the filtered voltage signal to obtain the amplitudes of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain as they vary with position; using the amplitudes of the compensated signal voltage at each frequency as they vary with position as the output of the magnetic transfer function, and using the amplitudes of the filtered voltage signal at each frequency as they vary with position as the input of the magnetic transfer function, to calculate and obtain the magnetic transfer function. The present application can accurately extract signal features in a high-noise background through time-varying information.

Description

Technical Field

[0001] The present application belongs to the technical field of ground-to-space frequency domain electromagnetic signal analysis, and specifically relates to a method for estimating magnetic transfer function parameters of ground-to-space frequency domain electromagnetic signals based on noise suppression and time-frequency analysis, which can achieve high-precision signal processing and parameter extraction. Background Art

[0002] Ground-to-air electromagnetic detection technology is an important means of detecting underground media, widely used in resource exploration, environmental monitoring, geological surveys, and engineering investigations. Its operating principle is to transmit electromagnetic signals from a ground-based transmitter into the underground medium and receive the electromagnetic response signals reflected or transmitted by the underground medium in the air, thereby obtaining information on the electrical characteristics of the underground structure. This technology has the significant advantages of high detection efficiency, low cost, and wide coverage.

[0003] In practical applications, aerial receivers are often affected by environmental noise, electromagnetic interference, and instrument noise during data collection. These noises can significantly degrade signal quality, which in turn affects the accurate calculation of the magnetic transfer function. The magnetic transfer function is a key physical parameter in ground-to-air electromagnetic signal processing. It is used to describe the relationship between the received response signal magnetic field and the transmitted current, reflecting the attenuation and phase characteristics of the electromagnetic signal propagating in the underground medium. The magnetic transfer function depends on the specific measurement geometry and underground conductivity structure, but is independent of the specific waveform of the transmitted current. Therefore, by performing characteristic analysis and magnetic transfer function estimation on ground-to-air electromagnetic signals at multiple frequencies, the distribution of electrical properties at different depths can be detected, providing an important basis for analyzing underground structures.

[0004] Currently, existing methods for analyzing ground-to-air electromagnetic signals mostly focus on Fourier transforms or time-domain methods, ignoring the non-stationary nature of the signals. Furthermore, traditional time-frequency analysis methods lack resolution in complex environments and cannot meet the requirements for high-precision calculations of magnetic transfer functions in ground-to-air electromagnetic detection. Summary of the Invention

[0005] The embodiment of the present application provides a method for estimating the parameters of the magnetic transfer function of ground-to-space frequency-domain electromagnetic signals, which solves the problem that traditional time-frequency analysis methods have insufficient resolution in complex environments and cannot meet the requirements for high-precision calculation of magnetic transfer functions in ground-to-space electromagnetic detection.

[0006] According to an embodiment of the present application, a method for estimating parameters of a ground-to-space frequency-domain electromagnetic signal magnetic transfer function is provided, comprising:

[0007] Noise suppression is performed on the original signal voltage collected by the magnetometer to obtain the compensated signal voltage;

[0008] filtering the emission current to obtain a filtered voltage signal;

[0009] Perform synchronous extraction and transformation on the compensated signal voltage and the filtered voltage signal to obtain the amplitude of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain as they change with position;

[0010] The amplitude of the compensated signal voltage at each frequency that changes with position is used as the output of the magnetic transfer function, and the amplitude of the filtered voltage signal at each frequency that changes with position is used as the input of the magnetic transfer function to calculate the magnetic transfer function.

[0011] Furthermore, the collected original signal voltage is subjected to noise suppression to obtain a compensated signal voltage, including:

[0012] Position Department The original signal voltage at the moment The predicted noise voltage on the corresponding component is subtracted from the component to obtain the signal voltage in the dynamic coordinate system;

[0013] The signal voltage in the dynamic coordinate system is corrected for heading deviation to obtain a compensated signal voltage, where the compensated signal voltage is the signal voltage corrected in the geodetic coordinate system.

[0014] Furthermore, the correction of the heading deviation of the signal voltage in the dynamic coordinate system includes: the unit impulse response function of the magnetometer transfer function, the unit impulse response function after the high-pass filter and the first The components are convolved.

[0015] Furthermore, the compensated signal voltage is subjected to synchronous extraction transformation, including:

[0016] The compensated signal voltage is subjected to short-time Fourier transform and an additional phase shift is added to obtain the result of short-time Fourier transform;

[0017] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and the first component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0018] Furthermore, the first component includes a first left-side term and a first right-side term, wherein the first left-side term is the product of the inverse of the Fourier transform of the unit impulse response function of the magnetometer transfer function and the window function and the synchronous extraction transform time-frequency analysis result of the compensated signal voltage, and the first right-side term is the first right-side term in the dynamic coordinate system. The synchronous extraction and transformation of the response signal magnetic field of each component is compared with the time-frequency analysis results of the first component in the dynamic coordinate system. The product of the time-frequency analysis results is obtained by synchronously extracting the response signal magnetic field of each component.

[0019] Furthermore, the filtered voltage signal is subjected to synchronous extraction transformation, including:

[0020] The filtered voltage signal is subjected to short-time Fourier transform and an additional phase shift is added to obtain the short-time Fourier transform result;

[0021] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and a second component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0022] Furthermore, the second component includes: the product of the first item, the fourth item and the third item, the first item is the Fourier transform of the unit impulse response function of the magnetometer and the window function product, the third item is the Fourier transform of the unit impulse response function of the high-pass filter and the window function product, and the fourth item is the time-frequency analysis result of the emission current after synchronous extraction and transformation.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] The method of the present application obtains high-resolution time-varying information, which can obtain the frequency composition of the overall signal with more focused energy in the local time domain, and can more clearly see the distribution and arrangement of each frequency band of the overall signal in the local time.

[0025] The magnetic transfer function in this application describes the relationship between the received signal (response signal magnetic field) and the excitation signal (transmitted current). By performing multi-band, high-resolution analysis of the signal, it accurately captures the signal's propagation characteristics in complex environments. This application, combined with time-frequency analysis and parameter extraction techniques using synchronous extraction transformations, enables precise extraction of signal features in high-noise environments, providing strong technical support for data analysis and underground structure detection in ground-to-air electromagnetic exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a flow chart of a method for estimating parameters of a ground-to-space frequency-domain electromagnetic signal magnetic transfer function provided by an embodiment of the present application;

[0027] Figure 2 This is a module block diagram of a ground-to-space frequency-domain electromagnetic signal magnetic transfer function parameter estimation system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0029] The embodiment of the present application converts the time-frequency analysis of the measured original signal voltage and the emission current into the time-frequency analysis of the corresponding response signal magnetic field and the emission current, extracts the parameters of the response signal magnetic field and the emission current corresponding to each frequency in the time-frequency analysis, and then obtains the magnetic transfer function.

[0030] See also Figure 1 As shown, the present application provides a method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals, comprising:

[0031] S101 performs noise suppression on the original signal voltage collected by the magnetometer to obtain the compensated signal voltage;

[0032] The raw signal voltage collected by the magnetometer is the ground-to-air frequency domain electromagnetic signal induced by the receiving coil. Before the magnetometer collects data, the transmitting current is set through the transmitter and the transmitting coil is used for transmission. Under the excitation of the transmitting current, the underground medium reflects or transmits the electromagnetic response signal. The magnetometer used can detect the raw signal voltage on three components. The collected raw signal voltage contains a large amount of noise signal.

[0033] First, the noise of the original signal voltage collected by the magnetometer is suppressed. The predicted noise voltage on the response component is subtracted from the original signal voltage to obtain the difference as the denoised signal voltage. For the airborne receiving device, the denoised signal voltage can also be corrected for heading deviation to obtain the compensated signal voltage or the corrected signal voltage.

[0034] S102 filters the emission current to obtain a filtered voltage signal;

[0035] The emission current can be filtered by a high-pass filter, and the output voltage of the high-pass filter is a filtered voltage signal.

[0036] S103 synchronously extracts and transforms the compensated signal voltage and the filtered voltage signal to obtain the amplitudes of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain as they change with position;

[0037] S104 uses the amplitude of the compensated signal voltage at each frequency that varies with position as the output of the magnetic transfer function, and uses the amplitude of the filtered voltage signal at each frequency that varies with position as the input of the magnetic transfer function to calculate the magnetic transfer function.

[0038] During the ground-to-space frequency domain electromagnetic detection process, at a certain moment and a certain location The response signal magnetic field is expressed as:

[0039] (1),

[0040] in, is the response signal magnetic field at any point in space, is the response signal magnetic field of the static magnetic field, It is the response signal magnetic field caused by the transmitted current.

[0041] Since in the frequency domain, the response signal magnetic field in the frequency domain and the emission current in the frequency domain The transfer function between The expression is as follows:

[0042] (2),

[0043] Therefore, to determine the magnetic transfer function, it is necessary to know the response signal magnetic field and the transmitted current at a specific point. However, since the magnetometer's receiving coil introduces noise when receiving data, noise suppression should be performed first.

[0044] In one embodiment, in the time domain, noise suppression is performed on the collected original signal voltage to obtain the compensated signal voltage, including:

[0045] Position Department The original signal voltage at the moment The predicted noise voltage on the corresponding component is subtracted from the component to obtain the signal voltage in the dynamic coordinate system;

[0046] The signal voltage in the dynamic coordinate system is corrected for heading deviation to obtain a compensated signal voltage, where the compensated signal voltage is the signal voltage corrected in the geodetic coordinate system.

[0047] For a certain moment and a certain location No. The actual measured original signal voltage of each component is subtracted from the predicted noise voltage on the corresponding component, and the difference is the signal voltage after denoising:

[0048] (3),

[0049] in, Indicates a moment and a certain location No. The actual measured raw signal voltage of each component, is the predicted noise voltage on the corresponding component , Represents the signal voltage after denoising. The signal voltage after denoising is in the dynamic coordinate system. In the dynamic coordinate system, Representative A portion.

[0050] The data needs to be converted from a dynamic coordinate system to a geodetic reference coordinate system.

[0051] At a certain moment and a certain location After the denoised signal voltage is corrected for heading deviation, we get:

[0052] (4),

[0053] in, Represents the rotation matrix of the dynamic coordinate system, which is used to convert the signal in the dynamic coordinate system to the matrix of the geodetic reference coordinate system. represents the inverse matrix of the heading deviation matrix, Indicates the first The response signal magnetic field of the components, represents the unit impulse response function of the magnetometer, Represents the unit impulse response function of the high-pass filter, * represents the convolution operation, Indicates the signal voltage after compensation.

[0054] At this point, the compensated signal voltage with noise eliminated and heading deviation corrected is obtained, which is formula (4).

[0055] In one embodiment, performing synchronous extraction transformation on the compensated signal voltage includes:

[0056] The compensated signal voltage is subjected to short-time Fourier transform and an additional phase shift is added to obtain the result of short-time Fourier transform;

[0057] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and the first component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0058] Perform synchronous extraction transformation on the filtered voltage signal, including:

[0059] The filtered voltage signal is subjected to short-time Fourier transform and an additional phase shift is added to obtain the short-time Fourier transform result;

[0060] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and a second component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0061] Perform time-frequency analysis of synchronous extraction transformation on the compensated signal voltage and the filtered signal voltage. Specifically, the time-frequency analysis of synchronous extraction transformation is as follows: In order to calculate the response signal magnetic field in the frequency domain and the emission current in the frequency domain The magnetic transfer function between the two is obtained by noise suppression, rotation, and projection in the geodetic coordinate system. For ease of analysis, the compensated signal voltage is subjected to time-frequency analysis. To obtain better time-frequency analysis parameters, a more energy-concentrated time-frequency analysis method, the Synchronous Extraction Transform (SET), is selected. The SET is a post-processing step of the Short-Time Fourier Transform (STFT) and offers the advantages of higher resolution and more concentrated energy.

[0062] Assume that the signal to be analyzed is The analysis signal here can be the compensated signal voltage or the filtered voltage signal. For the convenience of description, we uniformly use express, Represents a variable, which can be a time variable or a spatial position variable, and is obtained by conventional short-time Fourier transform:

[0063] (6),

[0064] Where, represents the result of the conventional short-time Fourier transform, represents a moving real-even window, Indicates the signal to be analyzed, is the frequency, Indicates time.

[0065] An additional phase shift Adding it to formula (6), we get formula (7):

[0066] (7),

[0067] Where, Represents the result of the short-time Fourier transform after adding an additional phase shift.

[0068] In order to obtain a more energy-intensive time-frequency representation method, the time-frequency coefficients with the same frequency are gathered to the position where they should appear, and only a certain frequency is used. The time-frequency coefficients at the position are used to generate a new set of time-frequency coefficients, namely the synchronous extraction transform (SET). Formula (7) can be further expressed as:

[0069] (8),

[0070] Where, Represents the result of synchronous extraction transformation, Indicates that only Extract The time-frequency coefficients of is the correlation between each frequency and time, here we use express.

[0071] After the filtered signal voltage, i.e. the emission current, passes through the high-pass filter, the output voltage of the high-pass filter is obtained:

[0072] (9),

[0073] in, represents the output voltage of the high-pass filter, represents the emission current in the time domain, Represents the unit impulse response function of the high-pass filter.

[0074] Next, we perform time-frequency analysis of synchronous extraction transformation on the compensated signal voltage and the filtered signal voltage:

[0075] Formula (8) is used to perform time-frequency analysis of the synchronous extraction transformation on formula (4), and the expression for each component can be obtained:

[0076] (10),

[0077] in, For variables The unit impulse response function of the high-pass filter is shown below, To represent variables The unit impulse response function of the magnetometer is shown below, For variables The following is the first The response signal magnetic field of the components, For variables Next change The unit impulse response function of the high-pass filter is shown below, Indicates changes The unit impulse response function of the magnetometer is shown below, Indicates changes The following is the first The response signal magnetic field of the components, Indicates changes Changes caused by The unit impulse response function of the magnetometer is shown below, Indicates changes The following is the first The response signal magnetic field of each component.

[0078] By exchanging the order of integration, formula (10) can be transformed into:

[0079] (11),

[0080] Let the variable ,but , after substituting into formula (11), we can get:

[0081] (12),

[0082] Let the variable ,but , after substituting into formula (12), we can get:

[0083] (13),

[0084] Select Exponential Window as the window function,

[0085] Then formula (13) can be written as:

[0086] (14),

[0087] Formula (14) can be written as:

[0088] (15),

[0089] in represents the time-frequency analysis result of synchronous extraction transformation of the compensated signal voltage, Indicates the first The synchronous extraction and transformation of the response signal magnetic field of each component is the time-frequency analysis result. Represents the Fourier transform of the product of the unit impulse response function of the high-pass filter and the window function, The Fourier transform of the unit impulse response function representing the magnetometer transfer function multiplied by the window function.

[0090] To facilitate calculation, formula (15) can be further simplified as:

[0091] (16),

[0092] in The inverse of the Fourier transform of the unit impulse response function representing the magnetometer transfer function multiplied by the window function.

[0093] Formula (16) is the first component, which includes the first left-side term and the first right-side term. The first left-side term is the product of the inverse of the Fourier transform of the unit impulse response function of the magnetometer transfer function and the window function and the synchronous extraction transform time-frequency analysis result of the compensated signal voltage. The first right-side term is the first component in the dynamic coordinate system. The synchronous extraction and transformation of the response signal magnetic field of each component is compared with the time-frequency analysis results of the first component in the dynamic coordinate system. The product of the time-frequency analysis results of the synchronous extraction transformation of the response signal magnetic field of the components, the first left-side term is equal to the first right-side term.

[0094] Similarly, the time-frequency analysis of synchronous extraction transformation is performed on formula (9), that is, the synchronous extraction transformation is performed on the filtered voltage signal, including:

[0095] The filtered voltage signal is subjected to short-time Fourier transform and an additional phase shift is added to obtain the short-time Fourier transform result;

[0096] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and a second component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0097] Similarly, the second component can be obtained. The second component includes: a second left-side term and a second right-side term. The second left-side term is the product of the Fourier transform of the unit impulse response function of the high-pass filter and the window function, and the time-frequency analysis result of the emission current after synchronous extraction transformation. The second right-side term is the time-frequency analysis result of the synchronous extraction transformation of the filtered voltage signal. The second right-side term is equal to the second right-side term. It can be expressed as:

[0098] (17),

[0099] represents the result of time-frequency analysis of the synchronous extraction transformation of the filtered voltage signal, represents the time-frequency analysis result of the emission current after synchronous extraction transformation, Represents frequency.

[0100] Response signal magnetic field and emission current The expression of the transfer function between is shown in formula (2), and formula (16) and formula (17) are used as the output signal of the magnetic transfer function. and input signal , which can be written as:

[0101] (18),

[0102] (19),

[0103] Substituting formula (18) and formula (19) into formula (2) yields:

[0104] (20).

[0105] This application simultaneously extracts and transforms the compensated signal voltage and the filtered voltage signal. After synchronous extraction and transformation time-frequency analysis, the amplitude of the compensated signal voltage and the filtered voltage signal at each frequency can be extracted over time. Yes and time It is equivalent to extracting the amplitude of the compensated signal voltage and the filtered voltage signal at each frequency as the position changes. Multiple frequencies form a matrix, that is, the output signal of the magnetic transfer function in matrix form can be obtained. and input signal , that is, the magnetic transfer function can be obtained .

[0106] The following describes a ground-to-space frequency domain electromagnetic signal magnetic transfer function parameter estimation system provided by an embodiment of the present invention. The ground-to-space frequency domain electromagnetic signal magnetic transfer function parameter estimation system described below and the ground-to-space frequency domain electromagnetic signal magnetic transfer function parameter estimation method described above can correspond to each other.

[0107] See also Figure 2 As shown, a system for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals comprises:

[0108] The compensation module is used to suppress the noise of the original signal voltage collected by the magnetometer to obtain the compensated signal voltage;

[0109] A high-pass filter, used to filter the emission current to obtain a filtered voltage signal;

[0110] A transformation module is used to synchronously extract and transform the compensated signal voltage and the filtered voltage signal to obtain the amplitude of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain as they change with position;

[0111] The calculation module is used to use the amplitude of the compensated signal voltage at each frequency changing with position as the output of the magnetic transfer function, and use the amplitude of the filtered voltage signal at each frequency changing with position as the input of the magnetic transfer function to calculate the magnetic transfer function.

[0112] In one embodiment, the compensation module performs noise suppression on the collected original signal voltage to obtain the compensated signal voltage, including: Department The original signal voltage at the moment The predicted noise voltage on the corresponding component is subtracted from the component to obtain the signal voltage in the dynamic coordinate system; the signal voltage in the dynamic coordinate system is corrected for the heading deviation to obtain the compensated signal voltage, which is the signal voltage corrected in the geodetic coordinate system.

[0113] In one embodiment, the compensation module corrects the heading deviation of the signal voltage in the dynamic coordinate system, including: the unit impulse response function of the magnetometer transfer function, the unit impulse response function after the high-pass filter, and the first The components are convolved.

[0114] In one embodiment, the conversion module performs synchronous extraction conversion on the compensated signal voltage, including: performing short-time Fourier transform on the compensated signal voltage and adding an additional phase shift to obtain a short-time Fourier transform result; using a certain frequency to convert the short-time Fourier transform result into a phase shift; The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and the first component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0115] In one embodiment, performing synchronous extraction transformation on the filtered voltage signal includes:

[0116] The filtered voltage signal is subjected to short-time Fourier transform and an additional phase shift is added to obtain the short-time Fourier transform result;

[0117] For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and a second component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

[0118] An embodiment of the present application provides an electronic device that may include: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. The processor may call logic instructions in the memory to execute the following method: performing noise suppression on the original signal voltage collected by the magnetometer to obtain a compensated signal voltage; filtering the emission current to obtain a filtered voltage signal; performing synchronous extraction and transformation on the compensated signal voltage and the filtered voltage signal to obtain the amplitudes of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain as a function of position; using the amplitudes of the compensated signal voltage at each frequency as a function of position as the output of the magnetic transfer function, and using the amplitudes of the filtered voltage signal at each frequency as a function of position as the input of the magnetic transfer function, to calculate the magnetic transfer function.

[0119] The logical instructions in the above-mentioned memory can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application, or the part that contributes to the existing technology, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program code.

[0120] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals, characterized in that: include: Noise suppression is performed on the original signal voltage collected by the magnetometer to obtain the compensated signal voltage; filtering the emission current to obtain a filtered voltage signal; Performing synchronous extraction transformation on the compensated signal voltage and the filtered voltage signal to obtain amplitudes of the compensated signal voltage and the filtered voltage signal at each frequency in the time domain that vary with position, wherein the synchronous extraction transformation on the compensated signal voltage includes: The compensated signal voltage is subjected to short-time Fourier transform and an additional phase shift is added to obtain the result of short-time Fourier transform; For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at the position are used to generate a new set of time-frequency coefficients, and a first component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained; The first component includes a first left-side term and a first right-side term, wherein the first left-side term is the product of the inverse of the Fourier transform of the unit impulse response function of the magnetometer transfer function and the window function and the synchronous extraction transform time-frequency analysis result of the compensated signal voltage, and the first right-side term is the first The synchronous extraction and transformation of the response signal magnetic field of each component is compared with the time-frequency analysis results of the first component in the dynamic coordinate system. The product of the time-frequency analysis results of the synchronous extraction transformation of the response signal magnetic field of each component; The amplitude of the compensated signal voltage at each frequency that changes with position is used as the output of the magnetic transfer function, and the amplitude of the filtered voltage signal at each frequency that changes with position is used as the input of the magnetic transfer function to calculate the magnetic transfer function.

2. The method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals according to claim 1, characterized in that: Noise suppression is performed on the collected original signal voltage to obtain the compensated signal voltage, including: Position Department The original signal voltage at the moment The predicted noise voltage on the corresponding component is subtracted from the component to obtain the signal voltage in the dynamic coordinate system; The signal voltage in the dynamic coordinate system is corrected for heading deviation to obtain a compensated signal voltage, where the compensated signal voltage is the signal voltage corrected in the geodetic coordinate system.

3. The method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals according to claim 2, characterized in that: The correction of the heading deviation of the signal voltage in the dynamic coordinate system includes: the unit impulse response function of the magnetometer transfer function, the unit impulse response function after the high-pass filter and the first The components are convolved.

4. The method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals according to claim 1, characterized in that: Perform synchronous extraction transformation on the filtered voltage signal, including: The filtered voltage signal is subjected to short-time Fourier transform and an additional phase shift is added to obtain the short-time Fourier transform result; For the result of short-time Fourier transform, use a certain frequency The time-frequency coefficients at are used to generate a new set of time-frequency coefficients, and a second component representing the amplitude of the compensated signal voltage varying with position at each frequency is obtained.

5. The method for estimating magnetic transfer function parameters of ground-to-space frequency-domain electromagnetic signals according to claim 4, characterized in that: The second component includes: the product of the first item, the fourth item and the third item, the first item is the Fourier transform of the unit impulse response function of the magnetometer and the window function product, the third item is the Fourier transform of the unit impulse response function of the high-pass filter and the window function product, and the fourth item is the time-frequency analysis result of the emission current after synchronous extraction transformation.

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