Dielectric constant inversion method based on ground-penetrating radar antenna location

Abstract

The disclosure provides a dielectric constant inversion method based on a ground penetrating radar antenna position, the method comprising: in response to a data processing request, acquiring radar data, wherein the radar data is generated by detecting a to-be-measured substance using a transmitting-receiving antenna of a ground penetrating radar; randomly extracting a plurality of random coordinate points in a hyperbolic curve pattern in a radar profile, wherein the radar profile is generated according to the radar data; fitting the plurality of random coordinate points to obtain a target hyperbolic function, wherein the target hyperbolic function comprises a vertex coordinate point; based on a preset dielectric constant equation, generating a target dielectric constant and a target reflector depth of the to-be-measured substance according to antenna parameters of the transmitting-receiving antenna, the plurality of random coordinate points and the vertex coordinate point, wherein the antenna parameters comprise an antenna position parameter.

Description

[0001] This disclosure claims priority to Chinese Patent Application No. 202311444332.4, filed on November 1, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of ground penetrating radar technology, and more specifically, to a method for inverting the dielectric constant based on the location of a ground penetrating radar antenna. Background Technology

[0003] Ground penetrating radar (GPR) is a highly efficient and non-destructive method for long-range detection of target media. It has wide applications in areas such as non-destructive testing of roads, non-destructive testing of concrete components, and moisture content detection. GPR uses the received signal obtained after the emitted high-frequency electromagnetic pulses undergo reflection, refraction, and absorption within the medium to image the electrical parameters of the probed area. GPR can be used to invert the dielectric constant of materials and detect subsurface structures. When radar waves propagate through a medium and encounter a reflector, a reflected signal is generated, and its phase axis forms a hyperbola.

[0004] In realizing the concept disclosed herein, the inventors discovered at least the following problems in the related technology: the accuracy of the dielectric constant and reflector depth calculated by the conventional method is poor, and it requires a lot of computing resources. Summary of the Invention

[0005] In view of this, embodiments of the present disclosure provide a method for inverting the dielectric constant based on the location of a ground-penetrating radar antenna.

[0006] One aspect of this disclosure provides a method for inverting the dielectric constant based on the radar antenna position, comprising: in response to a data processing request, acquiring radar data, the radar data being generated by detecting a material under test using a ground-penetrating radar transceiver antenna; randomly selecting multiple random coordinate points in a hyperbolic graph of a radar profile, the radar profile being generated based on the radar data; fitting the multiple random coordinate points to obtain a target hyperbolic function, the target hyperbolic function including vertex coordinate points; and generating the target dielectric constant and target reflector depth of the material under test based on a preset dielectric constant equation, according to the antenna parameters of the transceiver antenna, the multiple random coordinate points, and the vertex coordinate points, wherein the antenna parameters include antenna position parameters.

[0007] According to embodiments of this disclosure, before generating the radar profile, the method further includes: preprocessing the radar data to obtain preprocessed radar data, and generating the radar profile based on the preprocessed radar data.

[0008] According to embodiments of this disclosure, radar data is preprocessed to obtain preprocessed radar data, including: performing data editing processing on the radar data to obtain first intermediate data, wherein the data editing processing is used to remove redundant data when the ground penetrating radar stops detecting; performing self-check clearing processing on the first intermediate data to obtain second intermediate data, wherein the self-check clearing processing is used to remove the ground penetrating radar power-on self-check signal in the first intermediate data; performing background clearing processing on the second intermediate data to obtain third intermediate data, wherein the background clearing processing is used to remove horizontally distributed direct-coupled wave signals in the second intermediate data; and performing bandpass filtering processing on the third intermediate data to obtain preprocessed radar data, wherein the bandpass filtering processing is used to remove noise interference signals outside the effective bandwidth of the third intermediate data according to the effective bandwidth of the ground penetrating radar.

[0009] According to embodiments of this disclosure, preprocessing radar data to obtain preprocessed radar data further includes: performing DC signal clearing processing on first intermediate data to obtain new first intermediate data, and performing self-check clearing processing on the new first intermediate data; and / or performing gain processing on the preprocessed radar data using a gain function to obtain new preprocessed radar data.

[0010] According to embodiments of this disclosure, based on a preset dielectric constant equation, and according to the antenna parameters of the transmitting and receiving antennas, multiple random coordinate points, and vertex coordinate points, a target dielectric constant and a target reflector depth of the material to be tested are generated. This includes: for each random coordinate point, substituting the antenna parameters, vertex coordinate points, and random coordinate points into the preset dielectric constant equation to obtain an initial dielectric constant and an initial reflector depth corresponding to the random coordinate point; averaging multiple initial dielectric constants to obtain a target dielectric constant; and averaging multiple initial reflector depths to obtain a target reflector depth.

[0011] According to embodiments of this disclosure, before averaging the initial dielectric constant or the initial reflector depth, the method further includes: removing outliers from the plurality of initial dielectric constants or initial reflector depths to obtain a plurality of intermediate dielectric constants or a plurality of intermediate reflector depths; and averaging the plurality of intermediate dielectric constants or a plurality of intermediate reflector depths.

[0012] According to embodiments of this disclosure, the target hyperbolic function is:

[0013]

[0014] Where x0 is the horizontal projection distance corresponding to the vertex coordinates. Let y be the echo delay corresponding to the vertex coordinates, and a be the fitting coefficient.

[0015] According to embodiments of this disclosure, the preset dielectric constant equation is:

[0016]

[0017] Where W is the horizontal distance between the transmitting and receiving antennas, L is the vertical distance between the transmitting and receiving antennas, h1 is the height of the transmitting antenna above the ground, h2 is the height of the receiving antenna above the ground, H is the depth of the target reflector, y0 is the horizontal projection distance corresponding to the vertex of the hyperbola, θ1 is the refraction angle of the down-going wave when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbola is the same, θ2 is the incident angle of the up-going wave when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbola is the same, y is the horizontal distance between the midpoint of the transmitting and receiving antennas and the starting point, and x1 is the horizontal distance of the transmitting antenna (x1 = L / 2). 2 is the horizontal distance of the receiving antenna x2=-L / 2, y1 is the longitudinal distance of the transmitting antenna y1=yW / 2, y2 is the longitudinal distance of the receiving antenna y2=y+W / 2, a1 is the horizontal distance of the refraction point of the down-going wave at the ground, a2 is the horizontal distance of the refraction point of the up-going wave at the ground, b1 is the longitudinal distance of the refraction point of the down-going wave at the ground, b2 is the longitudinal distance of the refraction point of the up-going wave at the ground, c is the speed of light, t is the two-way time delay, t0 is the two-way time delay when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbolic function is the same, and ε is the target dielectric constant of the material to be measured.

[0018] According to embodiments of this disclosure, a radar profile is generated based on radar data. Multiple random coordinate points are randomly selected from the hyperbolic graph in the radar profile. These random coordinate points are then fitted to obtain a target hyperbolic function and vertex coordinates. Based on a preset dielectric constant equation, and according to the antenna parameters of the transmitting and receiving antennas, the multiple random coordinate points, and the vertex coordinates, the target dielectric constant and the target reflector depth of the material under test are generated. Because the positional relationship between the radar transmitting and receiving antennas is fully considered, the accuracy of calculating the dielectric constant and reflector depth is improved, while reducing the computational resources used. Attached Figure Description

[0019] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0020] Figure 1 A flowchart illustrating a method for inverting the dielectric constant based on the location of a ground-penetrating radar antenna according to an embodiment of the present disclosure is shown.

[0021] Figure 2 The diagram illustrates the propagation path of radar electromagnetic waves during the detection process according to an embodiment of the present disclosure.

[0022] Figure 3A schematic diagram of a radar cross-section view according to an embodiment of the present disclosure is shown;

[0023] Figure 4 A schematic diagram illustrating the error comparison of dielectric constant according to an embodiment of the present disclosure is shown.

[0024] Figure 5 A schematic diagram illustrating the error comparison of reflector depth according to an embodiment of the present disclosure is shown. Detailed Implementation

[0025] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0026] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0027] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0028] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0029] In realizing the concept of this disclosure, the traditional method for calculating the dielectric constant uses hyperbolic fitting, which employs a simplified model that assumes the transmitting and receiving radar antennas are in the same position and close to the ground, ignoring the influence of the antenna placement. However, in general, there is a distance between the transmitting and receiving antennas and a height difference from the ground. Therefore, it is necessary to consider the influence of the antenna placement to improve the accuracy of the dielectric constant and reflector depth estimation.

[0030] In view of this, this disclosure provides a method for inverting the dielectric constant based on the position of a ground-penetrating radar antenna. The method includes: in response to a data processing request, acquiring radar data, which is generated by detecting the material under test using the transceiver antenna of a ground-penetrating radar; randomly selecting multiple random coordinate points from a hyperbolic graph in a radar profile, the radar profile being generated based on the radar data; fitting the multiple random coordinate points to obtain a target hyperbolic function, the target hyperbolic function including vertex coordinates; and generating the target dielectric constant and target reflector depth of the material under test based on a preset dielectric constant equation, according to the antenna parameters of the transceiver antenna, the multiple random coordinate points, and the vertex coordinates, the antenna parameters including antenna position parameters.

[0031] Figure 1 A flowchart illustrating a method for inverting the dielectric constant based on the location of a ground-penetrating radar antenna according to an embodiment of the present disclosure is shown. Figure 2 The diagram illustrates the propagation path of radar electromagnetic waves during the detection process according to an embodiment of the present disclosure. Figure 3 A schematic diagram of a radar cross-section view according to an embodiment of the present disclosure is shown.

[0032] like Figure 1 As shown, the dielectric constant inversion method based on the location of the ground-penetrating radar antenna includes operations S101 to S104.

[0033] In operation S101, in response to a data processing request, radar data is acquired. The radar data is generated by using the transceiver antenna of a ground-penetrating radar to detect the substance under test.

[0034] In operation S102, multiple random coordinate points are randomly selected from the hyperbolic graph in the radar profile, which is generated based on radar data.

[0035] In operation S103, multiple random coordinate points are fitted to obtain the target hyperbolic function, which includes the vertex coordinates.

[0036] In operation S104, based on the preset dielectric constant equation, the target dielectric constant and target reflector depth of the material to be tested are generated according to the antenna parameters of the transmitting and receiving antennas, multiple random coordinate points and vertex coordinate points. The antenna parameters include antenna position parameters.

[0037] According to embodiments of this disclosure, the location of the transceiver antenna of the ground penetrating radar is not fixed; for example, it can be a ground penetrating radar that measures both close to the ground and suspended in the air.

[0038] According to embodiments of this disclosure, antenna parameters may include antenna position parameters, such as the height and horizontal / vertical distance between the transmitting and receiving antennas. Data processing requests may be generated based on operations entered by personnel on input devices of electronic devices such as computers.

[0039] According to embodiments of this disclosure, radar data is obtained by ground-penetrating radar using a transceiver antenna to detect the target material. The propagation path of the radar electromagnetic waves that generate the radar data during the detection process is as follows: Figure 2 As shown. Based on this radar data, the following is performed: Figure 3 The radar profile diagram (e.g., radar B-scan diagram) is drawn as shown. Then, a hyperbola is found in the radar profile diagram, and several random coordinate points are selected on the hyperbola to obtain the coordinates of each random coordinate point.

[0040] It should be noted that, Figure 2 In the diagram, Tx represents the transmitting antenna in the transmitting antenna, and Rx represents the receiving antenna.

[0041] According to embodiments of this disclosure, a target hyperbolic function is obtained by fitting a plurality of selected random coordinate points; the coordinates of the vertex coordinate points are then determined from the target hyperbolic function. Subsequently, the target dielectric constant and the target reflector depth of the test material are generated by substituting the plurality of random coordinate points, the vertex coordinate points, and the antenna parameters of the transmitting and receiving antennas into a preset dielectric constant equation.

[0042] According to embodiments of this disclosure, a radar profile is generated based on radar data. Multiple random coordinate points are randomly selected from the hyperbolic graph in the radar profile. These random coordinate points are then fitted to obtain a target hyperbolic function and vertex coordinates. Based on a preset dielectric constant equation, and according to the antenna parameters of the transmitting and receiving antennas, the multiple random coordinate points, and the vertex coordinates, the target dielectric constant and the target reflector depth of the material under test are generated. Because the positional relationship of the ground-penetrating radar transmitting and receiving antennas is fully considered, the accuracy of calculating the dielectric constant and reflector depth is improved, while simultaneously reducing the computational resources used.

[0043] According to embodiments of this disclosure, before generating the radar profile, the method further includes:

[0044] The radar data is preprocessed to obtain preprocessed radar data. A radar profile is then generated based on the preprocessed radar data.

[0045] According to embodiments of this disclosure, in order to further improve the accuracy of calculating the target dielectric constant and the target reflector depth, radar data can be preprocessed to reduce the impact of interference data in the radar data on the calculation accuracy.

[0046] According to embodiments of this disclosure, radar data is preprocessed to obtain preprocessed radar data, including:

[0047] The radar data undergoes data editing to obtain first intermediate data, which removes redundant data from when the ground-penetrating radar ceases detection. The first intermediate data undergoes self-check clearing to obtain second intermediate data, which removes the ground-penetrating radar's power-on self-check signal from the first intermediate data. The second intermediate data undergoes background clearing to obtain third intermediate data, which removes horizontally distributed direct-coupled wave signals from the second intermediate data. The third intermediate data undergoes bandpass filtering to obtain preprocessed radar data. Bandpass filtering removes noise interference signals outside the effective bandwidth of the radar from the third intermediate data, based on the radar's effective bandwidth.

[0048] According to embodiments of this disclosure, preprocessing the radar data to obtain preprocessed radar data further includes:

[0049] The first intermediate data undergoes DC signal clearing processing to obtain new first intermediate data, which is then subjected to self-checking and clearing processing. And / or, the preprocessed radar data is subjected to gain processing using a gain function to obtain new preprocessed radar data.

[0050] According to embodiments of this disclosure, the gain function is used to correct the signal amplitude of energy attenuation, which is beneficial for the identification of hyperbolas.

[0051] According to embodiments of this disclosure, based on a preset dielectric constant equation, and according to the antenna parameters of the transmitting and receiving antennas, multiple random coordinate points, and vertex coordinate points, the target dielectric constant and target reflector depth of the material to be measured are generated, including:

[0052] For each random coordinate point, the antenna parameters, vertex coordinates, and random coordinates are substituted into a preset dielectric constant equation to obtain the initial dielectric constant and initial reflector depth corresponding to the random coordinate point. Multiple initial dielectric constants are averaged to obtain the target dielectric constant. Multiple initial reflector depths are averaged to obtain the target reflector depth.

[0053] According to embodiments of this disclosure, for each random coordinate point, the initial dielectric constant and initial reflector depth corresponding to that random coordinate point are obtained by substituting the random coordinate point, antenna parameters, and vertex coordinate point into a preset dielectric constant equation. The target dielectric constant and target reflector depth of the test material can be obtained by summing and averaging multiple initial dielectric constants and initial reflector depths.

[0054] According to embodiments of this disclosure, before averaging the initial dielectric constant or the initial reflector depth, the method further includes:

[0055] Outliers in multiple initial dielectric constants or initial reflector depths are removed to obtain multiple intermediate dielectric constants or multiple intermediate reflector depths. These multiple intermediate dielectric constants or multiple intermediate reflector depths are then averaged.

[0056] According to embodiments of this disclosure, since outliers in the radar data after ground-penetrating radar detection affect the accuracy of calculating the target dielectric constant and the target reflector depth, outliers can be removed before averaging. Then, the target dielectric constant and target reflector depth are calculated using the remaining initial dielectric constant or initial reflector depth. Outliers can be determined using variance or standard deviation.

[0057] According to embodiments of this disclosure, before fitting multiple random coordinate points, point deletion can be performed on these random coordinate points, thereby utilizing the remaining random coordinate points for fitting. The purpose of point deletion is to remove random coordinate points located near the vertices of the hyperbola. A point distance threshold can be set; for each random coordinate point, if the lateral distance between the random coordinate point and the vertex is less than the point distance threshold, then the random coordinate point is deleted. The point distance threshold can be specifically set according to actual needs, for example, it can be set to 0.5.

[0058] According to embodiments of this disclosure, the target hyperbolic function is as shown in formula (1):

[0059]

[0060] Where x0 is the horizontal projection distance corresponding to the vertex coordinates. Let y be the echo delay corresponding to the vertex coordinates, and a be the fitting coefficient.

[0061] According to embodiments of this disclosure, the fitting coefficient α can be automatically generated by an electronic device such as a computer during the fitting process.

[0062] According to embodiments of this disclosure, the preset dielectric constant equation is as shown in formula (2):

[0063]

[0064] Where W is the horizontal distance between the transmitting and receiving antennas, L is the vertical distance between the transmitting and receiving antennas, h1 is the height of the transmitting antenna above the ground, h2 is the height of the receiving antenna above the ground, H is the depth of the target reflector, y0 is the horizontal projection distance corresponding to the vertex of the hyperbola, θ1 is the refraction angle of the down-going wave when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbola is the same, θ2 is the incident angle of the up-going wave when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbola is the same, y is the horizontal distance between the midpoint of the transmitting and receiving antennas and the starting point, and x1 is the horizontal distance of the transmitting antenna (x1 = L / 2). 2 is the horizontal distance of the receiving antenna x2=-L / 2, y1 is the longitudinal distance of the transmitting antenna y1=yW / 2, y2 is the longitudinal distance of the receiving antenna y2=y+W / 2, a1 is the horizontal distance of the refraction point of the down-going wave at the ground, a2 is the horizontal distance of the refraction point of the up-going wave at the ground, b1 is the longitudinal distance of the refraction point of the down-going wave at the ground, b2 is the longitudinal distance of the refraction point of the up-going wave at the ground, c is the speed of light, t is the two-way time delay, t0 is the two-way time delay when the horizontal projection distance between the midpoint of the transmitting and receiving antennas and the vertex of the hyperbolic function is the same, and ε is the target dielectric constant of the material to be measured.

[0065] According to embodiments of this disclosure, the horizontal coordinate of a random coordinate point is the horizontal distance y between the midpoint and the starting point of the transceiver antenna, and the vertical coordinate is the two-way delay t.

[0066] Figure 4 A schematic diagram illustrating the error comparison of dielectric constant according to an embodiment of the present disclosure is shown. Figure 5 A schematic diagram illustrating the error comparison of reflector depth according to an embodiment of the present disclosure is shown.

[0067] According to embodiments of this disclosure, Figure 4 and Figure 5 To compare the errors between the target dielectric constant and target reflector depth determined by the dielectric constant inversion method based on the antenna position of this disclosed ground-penetrating radar and those determined by traditional methods (without considering antenna position), the following analysis is conducted. Figure 4 and Figure 5 It is evident that the method disclosed herein determines the target dielectric constant and target reflector depth with higher accuracy and smaller error.

[0068] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A dielectric constant inversion method based on ground penetrating radar antenna position, comprising: in response to a data processing request, obtaining radar data generated by a transmitting and receiving antenna of the ground penetrating radar for detecting a to-be-measured substance; randomly extracting a plurality of random coordinate points in a hyperbolic curve pattern in a radar profile, the radar profile being generated according to the radar data; performing fitting processing on the plurality of random coordinate points to obtain a target hyperbolic curve function, the target hyperbolic curve function including a vertex coordinate point; based on a preset dielectric constant equation, generating a target dielectric constant and a target reflector depth of the to-be-measured substance according to antenna parameters of the transmitting and receiving antenna, the plurality of random coordinate points, and the vertex coordinate point, the antenna parameters including an antenna position parameter; wherein, based on the preset dielectric constant equation, generating the target dielectric constant and the target reflector depth of the to-be-measured substance according to the antenna parameters of the transmitting and receiving antenna, the plurality of random coordinate points, and the vertex coordinate point, comprises: for each random coordinate point, substituting the antenna parameters, the vertex coordinate point, and the random coordinate point into the preset dielectric constant equation to obtain an initial dielectric constant and an initial reflector depth corresponding to the random coordinate point; averaging a plurality of the initial dielectric constants to obtain the target dielectric constant; averaging a plurality of the initial reflector depths to obtain the target reflector depth; wherein, the preset dielectric constant equation is: wherein, W is a transverse distance of the transmitting and receiving antenna, L is a longitudinal distance of the transmitting and receiving antenna, h1 is a height of the transmitting antenna from the ground, h2 is a height of the receiving antenna from the ground, H is the target reflector depth, y0 is a horizontal projection distance corresponding to the vertex of the hyperbolic curve, θ1 is a refraction angle of the downlink wave when the horizontal projection distance of the midpoint of the transmitting and receiving antenna and the vertex of the hyperbolic curve function is the same, θ2 is an incident angle of the uplink wave when the horizontal projection distance of the midpoint of the transmitting and receiving antenna and the vertex of the hyperbolic curve function is the same, y is a horizontal distance of the midpoint of the transmitting and receiving antenna from the starting point, x1 is a horizontal distance x1 = L / 2 of the transmitting antenna, x2 is a horizontal distance x2 = -L / 2 of the receiving antenna, y1 is a longitudinal distance y1 = y-W / 2 of the transmitting antenna, y2 is a longitudinal distance y2 = y+W / 2 of the receiving antenna, a1 is a horizontal distance of the refraction point of the downlink wave at the ground, a2 is a horizontal distance of the refraction point of the uplink wave at the ground, b1 is a longitudinal distance of the refraction point of the downlink wave at the ground, b2 is a longitudinal distance of the refraction point of the uplink wave at the ground, c is the speed of light, t is the two-way time delay, t0 is the two-way time delay when the horizontal projection distance of the midpoint of the transmitting and receiving antenna and the vertex of the hyperbolic curve function is the same, and ε is the target dielectric constant of the to-be-measured substance.

2. The method of claim 1, wherein, Before generating the radar profile, further comprising: preprocessing the radar data to obtain preprocessed radar data; generating the radar profile according to the preprocessed radar data.

3. The method of claim 2, wherein, Preprocessing the radar data to obtain preprocessed radar data, comprising: The radar data is subjected to data editing processing to obtain first intermediate data, and the data editing processing is used to eliminate redundant data when the radar stops detecting; The first intermediate data is subjected to self-checking and cleaning processing to obtain second intermediate data, and the self-checking and cleaning processing is used to eliminate the ground penetrating radar startup self-checking signal in the first intermediate data; The second intermediate data is subjected to background cleaning processing to obtain third intermediate data, and the background cleaning processing is used to clean the horizontally distributed straight-coupled wave signal in the second intermediate data; The third intermediate data is subjected to band-pass filtering processing to obtain the preprocessed radar data, and the band-pass filtering processing is used to remove noise interference signals outside the effective bandwidth of the ground penetrating radar according to the effective bandwidth of the ground penetrating radar.

4. The method of claim 3, further comprising: subjecting the first intermediate data to direct current signal cleaning processing to obtain new first intermediate data, and subjecting the new first intermediate data to self-checking and cleaning processing; and / or subjecting the preprocessed radar data to gain processing using a gain function to obtain new preprocessed radar data.

5. The method of claim 1, wherein, Before the initial dielectric constant or the initial reflector depth is subjected to averaging processing, further comprising: eliminating outliers in a plurality of the initial dielectric constants or the initial reflector depths to obtain a plurality of intermediate dielectric constants or a plurality of intermediate reflector depths; subjecting a plurality of the intermediate dielectric constants or a plurality of the intermediate reflector depths to averaging processing.

6. The method of claim 1, wherein, The target hyperbolic function is: wherein x0 is the horizontal projection distance corresponding to the vertex coordinate point, is the echo delay corresponding to the vertex coordinate point, y is the echo delay, and a is the fitting coefficient.

Images