A Comprehensive Signal Processing Method, System, Terminal and Medium for Geological Imaging Radar

Abstract

The present invention relates to the technical field of geological imaging radar, and specifically provides a comprehensive signal processing method, system, terminal and medium for geological imaging radar. By preprocessing the echo signals received by the geological radar and simultaneously performing target detection processing and three-dimensional imaging processing on the preprocessed echo data, the coal-rock boundary surface can be effectively identified, and high-precision three-dimensional point cloud data of the coal-rock interface can be provided, providing basic data for intelligent mining decision-making control such as guiding the automatic adjustment of shearer equipment. Through the matching analysis and processing of the data results of target detection processing and three-dimensional imaging processing, the intelligent function of the geological imaging radar is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of geological imaging radar, and specifically to a comprehensive signal processing method, system, terminal and medium for geological imaging radar. Background Art

[0002] Conventional ground penetrating radars are generally used for quality monitoring of urban construction projects, non-destructive detection of the quality of highways and airport runways, monitoring of underground pipeline lines, geological disasters, tunnel detection, archaeological excavations, etc. The signal processing process is to generate a two-dimensional or three-dimensional detection image of the echo signal, and then the detection image of the ground penetrating radar is interpreted manually. This way of manually interpreting the radar echo image is affected by the subjectivity and experience of the interpreters on the one hand; on the other hand, the dependence on manual labor determines that conventional ground penetrating radars cannot be used for unmanned mining in intelligent mines. Summary of the Invention

[0003] In order to overcome the defects of the above-mentioned prior art, the purpose of the present invention is to provide a comprehensive signal processing method, system, terminal and medium for geological imaging radar, so as to solve the technical problems that the intelligent function of comprehensive signal processing of geological imaging radar cannot be realized in the prior art books and the monitoring accuracy of radar echo images is low.

[0004] The present invention is realized through the following technical solutions:

[0005] A comprehensive signal processing method for geological imaging radar includes the following steps:

[0006] Step 1, obtaining the echo signal received by the ground penetrating radar and performing preprocessing;

[0007] Step 2, simultaneously performing target detection processing and three-dimensional imaging processing on the preprocessed echo data;

[0008] Step 3, performing matching analysis processing on the data results of the target detection processing and the three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the geological imaging radar is completed.

[0009] Preferably, the echo signal received by the ground penetrating radar includes a target echo signal, an echo signal generated by direct reflection on the ground surface, a direct coupling signal, and an interference noise signal.

[0010] Preferably, in Step 1, preprocessing the echo signal received by the ground penetrating radar includes the following steps:

[0011] Step 11, suppressing noise of the echo signal;

[0012] Step 12, suppressing radio frequency interference of the echo signal after noise suppression;

[0013] Step 13: Remove the direct wave from the echo signal after radio frequency interference suppression to obtain echo data.

[0014] Preferably, in step 2, perform target detection processing on the preprocessed echo data, including the following steps:

[0015] S1: Calculate the power spectrum of the echo data;

[0016] S2: Track the minimum value of the echo data according to the power spectrum of the echo data;

[0017] S3: Calculate the target presence probability using the ratio of the power spectrum of the echo data to the minimum value of the echo data;

[0018] S4: Calculate the time-frequency smoothing parameter through the target presence probability;

[0019] S5: Calculate the estimated value of the noise power spectrum through the time-frequency smoothing parameter;

[0020] S6: Compare the power spectrum of the echo data with the estimated value of the noise power spectrum. When the power spectrum of the echo data in a certain range cell is greater than the estimated value of the noise power spectrum, the power spectrum of the echo data in this range cell is the target echo data.

[0021] Preferably, in step 2, perform three-dimensional imaging processing on the preprocessed echo signal, including the following steps:

[0022] L1: Extract the first sampling value of each receiving period in the echo data corresponding to a frequency point of a group of transceiver array elements to form a sequence; after performing the FFT fast algorithm on the sequence, perform signal accumulation within the frequency point, and take the spectral value corresponding to the spectral peak position as the output of this frequency point;

[0023] L2: Repeat step 1, traverse the echo data corresponding to all frequency points of this group of transceiver array elements, obtain the spectral values corresponding to each frequency point, form a stepped-frequency signal of multiple points, and perform IFFT inverse fast Fourier transform processing on the stepped-frequency signal to obtain the synthesized echo signal between frequency points;

[0024] L3: Repeat step 2, traverse all transceiver array elements, and obtain the synthesized echo signals between frequency points of all array elements;

[0025] L4: Divide the imaging area for the synthesized echo signals between frequency points of all array elements, calculate the round-trip time delay of each pixel point to the transceiver array element combination, extract the corresponding echo value according to this time delay and perform phase compensation on it, and accumulate all the echo values after phase compensation to obtain the three-dimensional imaging result of the detection area.

[0026] A geological imaging radar integrated signal processing system includes

[0027] A signal preprocessing module, which is used to obtain the echo signal received by the ground penetrating radar and perform preprocessing;

[0028] A data processing module, which is used to perform target detection processing and three-dimensional imaging processing on the preprocessed echo data simultaneously;

[0029] A data matching module, which is used to perform matching analysis processing on the data results of target detection processing and three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the ground imaging radar is completed.

[0030] A mobile terminal includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of a method for comprehensive signal processing of a ground imaging radar as described above are implemented.

[0031] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps of a method for comprehensive signal processing of a ground imaging radar as described above are implemented.

[0032] Compared with the prior art, the present invention has the following beneficial technical effects:

[0033] The present invention provides a method for comprehensive signal processing of a ground imaging radar. By preprocessing the echo signal received by the ground penetrating radar and simultaneously performing target detection processing and three-dimensional imaging processing on the preprocessed echo data, the coal-rock boundary surface can be effectively identified, and high-precision three-dimensional point cloud data of the coal-rock interface can be provided, providing basic data for guiding intelligent mining decision-making control such as automatic adjustment of shearer equipment. By performing matching analysis processing on the data results of target detection processing and three-dimensional imaging processing, the intelligent function of the ground imaging radar is improved.

[0034] The present invention provides a system for comprehensive signal processing of a ground imaging radar. Through intelligent signal processing by a signal preprocessing module, a data processing module, and a data matching module, it is a necessary means to achieve the geological "transparency" of the coal mining face, which can realize the automatic and precise coal cutting of the shearer along the coal-rock interface, and can realize less or even no human operation; at the same time, it can increase the raw coal output, reduce the content of coal gangue, increase economic benefits, and avoid environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of the method for comprehensive signal processing of a ground imaging radar in the present invention;

[0036] Figure 2 It is a flow chart of the three-dimensional BP imaging algorithm in the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0038] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings:

[0040] See Figure 1 , in an embodiment of the present invention, a comprehensive signal processing method for geological imaging radar is provided, including the following steps:

[0041] Step 1, preprocess the echo signal received by the ground penetrating radar;

[0042] Specifically, preprocessing the echo signal received by the ground penetrating radar includes the following steps:

[0043] Step 11, suppress the noise of the echo signal;

[0044] It mainly includes various random noises (external random noises, system thermal noises), and the computationally small average processing and one-dimensional digital filter can be selected to complete it.

[0045] Step 12, suppress the radio frequency interference of the echo signal after noise suppression;

[0046] The working frequency band of the ground penetrating radar is generally very wide, covering the VHF / UHF band and the mobile communication frequency band. The electromagnetic wave signals of radio systems in this frequency band will enter the radar receiver to form radio frequency interference, including radio, television, cellular mobile phones, etc. The frequency domain notch method can be selected for RFI suppression.

[0047] Step 13: Remove the direct wave from the echo signal after RF interference suppression to obtain echo data.

[0048] Due to the complexity of the underground environment, the echo form of the ground penetrating radar signal can be expressed as

[0049] f(t) = d(t) + s(t) + n(t)

[0050] Where: d(t) represents the direct wave; s(t) is the reflected wave component of the target; n(t) is the noise and interference. Signals other than s(t) can be called clutter. The preprocessing of the ground penetrating radar signal is to remove this clutter for subsequent imaging.

[0051] The direct wave includes the directly coupled wave component between antennas and the direct reflected wave component on the surface of the formation or other environmental media, which is a relatively strong interference in the radar signal. Methods for removing the direct wave can include the principal component analysis method, etc.

[0052] The principal component analysis method is a linear transformation processing method based on the minimum mean square error. According to the difference between the direct wave and the target echo on the two-dimensional scan image, project them into different subspaces. After removing the subspace where the direct wave is located, the reconstructed signal can achieve the removal of the direct wave.

[0053] The principal component analysis method has certain advantages compared with the time window removal method and the average cancellation method. It is not affected by the arrival time of the direct wave and the target reflected wave in the echo signal and has relatively little impact on the target reflected wave. The present invention uses the principal component analysis method to remove the direct wave.

[0054] For the case where the ground penetrating radar measures along a survey line, assuming that the number of sampling points in time of the ground penetrating radar is N and the number of measurement points of the survey line is M, the B-Scan data received by the ground penetrating radar can be expressed as matrix W R ∈R M×N , perform singular value decomposition on W R

[0055] W R = UDV T

[0056] Where: U = {u1, u2,..., u m} ∈ R M×N ; V = {v1, v2,..., v n} ∈ R M×N ; D is an M×N diagonal matrix, and the elements di on its diagonal are the singular values of WR, and d1 ≥ d2 ≥... ≥ dP, P = min{M, N}.

[0057] W R can be expressed as

[0058]

[0059] Since the direct wave signals at each measurement point of the same survey line do not vary much, the rank of the direct wave matrix is nearly 1. Therefore, the direct wave component in the signal can be removed by simply subtracting a matrix of rank 1 from the echo matrix WR.

[0060] According to the properties of singular value decomposition, the echo after removing the direct wave for a matrix of rank 1 can be expressed as

[0061]

[0062] For a ground penetrating radar, the distances between each antenna and the transmitting antenna are different, but the spacing between each antenna and the transmitting antenna is fixed. Therefore, after the ground penetrating radar system measures and obtains three-dimensional data along a certain direction, by extracting the signals received by each receiving antenna, the direct waves of each receiving antenna can be removed using the principal component analysis method. Removing the direct waves of all receiving antennas is equivalent to removing the direct waves in the three-dimensional data.

[0063] Step 2: Perform target detection processing and three-dimensional imaging processing on the preprocessed echo data simultaneously;

[0064] Specifically, the target detection processing of the preprocessed echo data includes the following steps:

[0065] S1: Calculate the power spectrum of the echo data;

[0066] Suppose the echo data received by a stepped frequency continuous wave ground penetrating radar is:

[0067] y(t) = s(t) + n(t) (1)

[0068] where s(t) is the target signal and n(t) is the noise. t represents the sampling time label.

[0069] Further assume that s(t) and n(t) are statistically independent and both have zero mean. To transform the signal into the frequency domain, the signal is divided into frame signals of length L sampling points with an overlap of R points between frames. Perform FFT calculation on the frame signals to obtain the signal in the frequency domain:

[0070]

[0071] where λ is the frame number, i.e., the label of time, k is the label of the frequency point, λ ∈ Z, k ∈ {0, 1,... L - 1}, h(u) is a window sequence, and assume

[0072] First, use a smoothing process to roughly estimate the noise power spectral density P(λ, k):

[0073] P(λ,k) = αP(λ - 1,k) + (1 - α)|Y(λ,k)| 2 (3)

[0074] where α is the smoothing parameter, and the further estimate of the noise power σ N 2 (λ,k) is determined by taking the minimum value of P(λ,k) within a sliding window.

[0075] where P(λ,k) is the smoothed power spectrum, λ is the frame label, k is the frequency bin label, and |Y(λ,k)| 2 is the power spectrum of the echo signal, and η = 0.7.

[0076] S2. Track the minimum value of the echo data according to the power spectrum of the echo data;

[0077] Use the recursive rule to track the minimum value:

[0078] If P min(λ - 1,k) < P(λ,k)

[0079] Then

[0080] Otherwise P min(λ,k) = P(λ,k)

[0081] where P min(λ,k) is the local minimum power spectrum of the echo signal, β = 0.8, and γ = 0.998.

[0082] S3. Calculate the target presence probability using the ratio of the power spectrum of the echo data to the minimum value of the echo data;

[0083] Calculate the target presence probability using the ratio of the power spectrum of the echo signal to its local minimum value, which is expressed as follows:

[0084] Sr(λ,k) = P(λ,k) / P min(λ,k) 4)

[0085] Compare the calculated probability with the empirical frequency value δ(k). If it is greater than δ(k), it is judged as the target presence frequency bin. Whether the target exists is judged by the following formula:

[0086] If Sr(λ,k) > δ(k)

[0087] Then I(λ,k) = 1 Target exists (5)

[0088] Otherwise I(λ,k) = 0 Interference noise

[0089] Update the target presence probability:

[0090] P(λ,k) = α pp(λ - 1,k)+(1 - α p )I(λ,k) (6)

[0091] Where α p = 0.2

[0092] S4. Calculate the time - frequency smoothing parameter through the target presence probability;

[0093] Using the above - mentioned target presence probability estimation, calculate the time - frequency smoothing parameter α s (λ,k) with the following formula:

[0094] α s (λ,k)=α d +(1 - α d )p(λ,k) (7)

[0095] α d = 0.85, and the value range of α s (λ,k) is: α d ≤α s (λ,k)≤1

[0096] S5. Calculate the estimated value of the noise power spectrum through the time - frequency smoothing parameter;

[0097] Finally, after calculating the time - frequency smoothing parameter α s (λ,k), use the following formula to update the noise power spectrum:

[0098] D(λ,k)=α s (λ,k)D(λ - 1,k)+(1 - α s (λ,k))|Y(λ,k)| 2 (8)

[0099] Where D(λ,k) is the estimated value of the noise power spectrum,

[0100] S6. Compare the estimated values of the echo data power spectrum and the noise power spectrum. When the echo data power spectrum in a certain range cell is greater than the estimated value of the noise power spectrum, the echo data power spectrum in that range cell is the target echo data.

[0101] Specifically, perform three - dimensional imaging processing on the pre - processed echo signal, as Figure 2 shown, including the following steps:

[0102] L1. Extract the first sampling value of each receiving period in the echo data corresponding to a frequency point of a group of transceiver array elements to form a sequence; after performing the FFT fast algorithm on the sequence, perform in - frequency - point signal accumulation, and take the spectral value corresponding to the spectral peak position as the output of this frequency point;

[0103] L2. Repeat step 1, traverse the echo data of all frequency points corresponding to this group of transceiver array elements, obtain the spectral values corresponding to each frequency point, form a stepped-frequency signal with multiple points, perform inverse fast Fourier transform (IFFT) processing on the stepped-frequency signal to obtain the synthesized echo signal between frequency points;

[0104] L3. Repeat step 2, traverse all transceiver array elements, and obtain the synthesized echo signals between frequency points of all array elements;

[0105] L4. Divide the imaging area for the synthesized echo signals between frequency points of all array elements, calculate the round-trip time delay from each pixel point to the transceiver array element combination, extract the corresponding echo value according to this time delay and perform phase compensation on it, and accumulate all the echo signals after phase compensation to obtain the three-dimensional imaging result of the detection area.

[0106] Step 3. Perform matching analysis processing on the data results of target detection processing and three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the geological imaging radar is completed.

[0107] The present invention also provides a comprehensive signal processing system for a geological imaging radar, including a signal preprocessing module, a data processing module, and a data matching module;

[0108] The signal preprocessing module is used to preprocess the echo signal received by the geological radar;

[0109] The data processing module is used to simultaneously perform target detection processing and three-dimensional imaging processing on the preprocessed echo data;

[0110] The data matching module is used to perform matching analysis processing on the data results of target detection processing and three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the geological imaging radar is completed.

[0111] The present invention also provides a mobile terminal, including a memory, a processor, and a computer program stored in the memory and executable on the processor, such as a comprehensive signal processing program for a geological imaging radar.

[0112] When the processor executes the computer program, the steps of the above-mentioned comprehensive signal processing method for a geological imaging radar are implemented, for example:

[0113] Step 1. Obtain the echo signal received by the geological radar and perform preprocessing;

[0114] Step 2. Simultaneously perform target detection processing and three-dimensional imaging processing on the preprocessed echo data;

[0115] Step 3. Perform matching analysis processing on the data results of target detection processing and three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the geological imaging radar is completed.

[0116] Alternatively, when the processor executes the computer program, it realizes the functions of the various modules in the above system. For example, a signal preprocessing module is used to obtain and preprocess the echo signals received by the ground penetrating radar.

[0117] A data processing module is used to simultaneously perform target detection processing and three-dimensional imaging processing on the preprocessed echo data.

[0118] A data matching module is used to perform matching analysis processing on the data results of the target detection processing and the three-dimensional imaging processing. When the data results match, the comprehensive signal processing of the ground imaging radar is completed.

[0119] Exemplarily, the computer program can be divided into one or more modules / units. The one or more modules / units are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, and these instruction segments are used to describe the execution process of the computer program in the mobile terminal.

[0120] For example, the computer program can be divided into a signal preprocessing module, a data processing module, and a data matching module. The specific functions of each module are as follows:

[0121] The signal preprocessing module is used to obtain and preprocess the echo signals received by the ground penetrating radar.

[0122] The data processing module is used to simultaneously perform target detection processing and three-dimensional imaging processing on the preprocessed echo data.

[0123] The data matching module is used to perform matching analysis processing on the data results of the target detection processing and the three-dimensional imaging processing. When the data results match, the comprehensive signal processing of the ground imaging radar is completed.

[0124] The mobile terminal can be a computing device such as a desktop computer, a notebook, a palm computer, and a cloud server. The mobile terminal may include, but is not limited to, a processor and a memory.

[0125] The so-called processor may be a Central Processing Unit (CPU), or may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The processor is the control center of the mobile terminal and connects various parts of the entire mobile terminal through various interfaces and circuits.

[0126] The memory can be used to store the computer program and / or module. The processor realizes various functions of the mobile terminal by running or executing the computer program and / or module stored in the memory and calling the data stored in the memory.

[0127] The memory may mainly include a program storage area and a data storage area. Among them, the program storage area can store an operating system, application programs required for at least one function (such as a sound playback function, an image playback function, etc.); the data storage area can store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory may include high-speed random access memory and may also include non-volatile memory, such as a hard disk, memory, plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, at least one magnetic disk storage device, flash device, or other volatile solid-state storage devices.

[0128] The present invention also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for comprehensively processing geological imaging radar signals are realized.

[0129] If the modules / units integrated in the mobile terminal are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium.

[0130] Based on such understanding, all or part of the processes in the above methods of the present invention can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above geological imaging radar integrated signal processing method can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file or some intermediate form, etc.

[0131] The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0132] It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: still modifications or equivalent substitutions can be made to the specific embodiments of the present invention, and any modification or equivalent substitution that does not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A comprehensive signal processing method for geological imaging radar, characterized in that It includes the following steps: Step 1: Obtain the echo signal received by the ground penetrating radar and perform preprocessing; Step 2: Perform target detection processing and 3D imaging processing on the preprocessed echo data simultaneously; Among them, performing target detection processing on the preprocessed echo data includes the following steps: S1: Calculate the power spectrum of the echo data; S2: Track the minimum value of the echo data according to the power spectrum of the echo data; S3: Calculate the target presence probability by using the ratio of the power spectrum of the echo data to the minimum value of the echo data; S4: Calculate the time-frequency smoothing parameter through the target presence probability; S5: Calculate the estimated value of the noise power spectrum through the time-frequency smoothing parameter; S6: Compare the power spectrum of the echo data with the estimated value of the noise power spectrum. When the power spectrum of the echo data in a certain range cell is greater than the estimated value of the noise power spectrum, the power spectrum of the echo data in this range cell is the target echo data; Among them, performing 3D imaging processing on the preprocessed echo signal includes the following steps: L1: Extract the first sampling value of each receiving period in the echo data corresponding to a frequency point of a group of transmitting and receiving array elements to form a sequence; and after performing the FFT fast algorithm on the sequence, perform signal accumulation within the frequency point, and take the spectral value corresponding to the spectral peak position as the output of this frequency point; L2: Repeat step 1, traverse the echo data corresponding to all frequency points of this group of transmitting and receiving array elements, obtain the spectral values corresponding to each frequency point, form a stepped-frequency signal of multiple points, and perform IFFT inverse fast Fourier transform processing on the stepped-frequency signal to obtain the synthetic echo signal between frequency points; L3: Repeat step 2, traverse all transmitting and receiving array elements, and obtain the synthetic echo signal between frequency points of all array elements; L4: Divide the imaging area of the synthetic echo signal between frequency points of all array elements, calculate the round-trip time delay of each pixel point to the combination of transmitting and receiving array elements, extract the corresponding echo value according to this time delay and perform phase compensation on it, and accumulate all the echo signals after phase compensation to obtain the 3D imaging result of the detection area; Step 3: Perform matching analysis processing on the data results of the target detection processing and the 3D imaging processing. When the data results match, the comprehensive signal processing work of the ground penetrating radar is completed.

2. A comprehensive signal processing method for geological imaging radar according to claim 1, characterized in that The echo signal received by the ground penetrating radar includes a target echo signal, an echo signal generated by direct reflection on the ground surface, a direct coupling signal, and an interference noise signal.

3. A comprehensive signal processing method for geological imaging radar according to claim 1, characterized in that, In step 1, performing preprocessing on the echo signal received by the ground penetrating radar includes the following steps: Step 11: Suppress the noise of the echo signal; Step 12: Suppress the radio frequency interference of the echo signal after noise suppression; Step 13: Remove the direct wave from the echo signal after radio frequency interference suppression to obtain the echo data.

4. A comprehensive signal processing system for geological imaging radar, characterized in that, Include A signal preprocessing module for obtaining the echo signal received by the ground penetrating radar and performing preprocessing; A data processing module for performing target detection processing and 3D imaging processing on the preprocessed echo data simultaneously; among them, performing target detection processing on the preprocessed echo data includes the following steps: S1: Calculate the power spectrum of the echo data; S2: Track the minimum value of the echo data according to the power spectrum of the echo data; S3. Calculate the target presence probability by using the ratio of the power spectrum of the echo data to the minimum value of the echo data. S4. Calculate the time-frequency smoothing parameter based on the target presence probability. S5. Calculate the estimated value of the noise power spectrum by using the time-frequency smoothing parameter. S6. Compare the power spectrum of the echo data with the estimated value of the noise power spectrum. When the power spectrum of the echo data in a certain range cell is greater than the estimated value of the noise power spectrum, the power spectrum of the echo data in this range cell is the target echo data. Among them, performing three-dimensional imaging processing on the preprocessed echo signal includes the following steps: L1. Extract the first sampling value of each receiving period in the echo data corresponding to a frequency point of a group of transmitting and receiving array elements to form a sequence; after performing the FFT fast algorithm on the sequence, perform in-frequency signal accumulation, and take the spectral value corresponding to the spectral peak position as the output of this frequency point. L2. Repeat step 1, traverse the echo data corresponding to all frequency points of this group of transmitting and receiving array elements, obtain the spectral values corresponding to each frequency point, form a stepped-frequency signal of multiple points, and perform IFFT inverse fast Fourier transform processing on the stepped-frequency signal to obtain the synthetic echo signal between frequency points. L3. Repeat step 2, traverse all transmitting and receiving array elements, and obtain the synthetic echo signals between frequency points of all array elements. L4. Divide the imaging area for the synthetic echo signals between frequency points of all array elements, calculate the round-trip time delay of each pixel point to the combination of transmitting and receiving array elements, extract the corresponding echo value according to this time delay and perform phase compensation on it, and accumulate all the echo values after phase compensation to obtain the three-dimensional imaging result of the detection area. The data matching module is used to perform matching analysis processing on the data results of target detection processing and three-dimensional imaging processing. When the data results match, the comprehensive signal processing work of the geological imaging radar is completed.

5. A mobile terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method for comprehensively processing signals of a geological imaging radar according to any one of claims 1 to 3.

6. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for comprehensively processing signals of a geological imaging radar according to any one of claims 1 to 3.

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