Multi-frequency communication detection terminal control method for pipeline detection

Abstract

The invention discloses a multi-frequency communication detection terminal control method for pipeline detection. According to the method, by constructing a standard microwave signal feature database of a multi-frequency communication detection terminal, feature matching and decomposition are carried out on mixed multi-frequency microwave signals in a target pipeline area, and precise separation of single-frequency signal flows is achieved. A data channel dynamic matching mechanism of the transmitting end and the receiving end is established based on the decomposed single-frequency signal flow information, modeling is performed in combination with the influence of pipeline environment characteristics on frequency drift, and a frequency drift compensation model with environmental adaptability is constructed. And when the communication link is abnormal, self-adaptive correction is carried out on the signal flow through a real-time environment data acquisition and frequency compensation algorithm, and rapid reconstruction of the communication link is completed. The problem of communication stability caused by frequency drift in a complex pipeline environment is effectively solved, and the reliability and the detection precision of a pipeline detection system are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline detection, and particularly to a multi-frequency communication detection terminal control method for pipeline detection. Background Art

[0002] With the rapid development of urban underground pipe networks, multiple pipelines such as gas, water, electricity, and communication are laid in parallel, and the underground space environment is becoming increasingly complex, posing higher requirements for the accuracy and reliability of pipeline detection technologies. Currently, commonly used pipeline detection methods such as electromagnetic induction and ground penetrating radar are limited by factors such as detection depth, material adaptability, and electromagnetic interference, and have problems such as large positioning errors and high detection failure rates in complex environments.

[0003] Multi-frequency communication detection technology has been gradually applied to the field of underground pipeline detection due to its strong signal penetration and high anti-interference ability. However, most existing systems adopt fixed frequency configurations and lack the dynamic response ability to environmental changes. Especially when facing situations such as signal mixing interference and frequency drift, it is easy to cause communication link failures or detection misjudgments. At the same time, current multi-frequency signal processing methods mostly stay at simple filtering and demodulation, and fail to fully exploit the time-frequency domain characteristics of signals, limiting the signal recognition accuracy.

[0004] In addition, the channel characteristics change violently in a complex pipeline environment, resulting in obvious frequency offsets of communication signals. Existing methods usually rely on manual experience for adjustment and lack a systematic frequency compensation model, affecting the automation and intelligence levels of the system.

[0005] Therefore, there is an urgent need for a multi-frequency communication detection control method that can achieve signal feature extraction, mixed signal decomposition, dynamic matching of data channels, and frequency compensation to improve the communication stability between terminals and the accuracy and adaptability of underground pipeline detection. Summary of the Invention

[0006] To solve at least one of the above technical problems, the present invention proposes a multi-frequency communication detection terminal control method for pipeline detection.

[0007] The first aspect of the present invention provides a multi-frequency communication detection terminal control method for pipeline detection, including: extracting the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency to construct a signal characteristic database; acquiring the mixed multi-frequency microwave signals in the target pipeline detection area, decomposing the mixed multi-frequency microwave signals into single-frequency signal streams according to the signal characteristic database, and determining the single-frequency signal stream information; matching the data channels between the multi-frequency signal transmitter and the receiver according to the single-frequency signal stream information, and establishing a data link according to the matched data channels; If there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; According to the environmental information of the pipeline detected by the terminal with a failed data link and the frequency drift compensation model, perform frequency compensation on the decomposed single-frequency signal stream, and reconnect the transmitter and the receiver according to the single-frequency signal stream after frequency compensation.

[0008] In this solution, the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency are extracted to construct a signal characteristic database, specifically: Collect the standard microwave signals transmitted by the multi-frequency communication detection terminal at each operating frequency in time series to obtain an original signal matrix, where each row represents a sampling time point and each column represents the sampling data of an operating frequency; Perform centering processing on the original signal matrix, calculate the mean value of the data of each frequency channel, and subtract the mean value of the corresponding channel from each element of the original signal matrix to obtain a centered signal matrix; Introduce the singular value decomposition algorithm, and decompose the centered signal matrix into the product form of a left singular vector matrix, a singular value diagonal matrix, and a right singular vector matrix according to the singular value decomposition algorithm. The column vectors of the left singular vector matrix represent the signal characteristic patterns in the time dimension, the row vectors of the right singular vector matrix represent the signal characteristic patterns in the frequency dimension, and the diagonal elements of the singular value diagonal matrix represent the energy weights of each characteristic pattern; According to the singular values of the singular value diagonal matrix, select the signal characteristic patterns corresponding to the first K largest singular values, use the first K columns of the left singular vector matrix as the time characteristic basis vectors, and the first K rows of the right singular vector matrix as the frequency characteristic basis vectors to construct a reduced-dimensional signal characteristic projection space; Classify and store the time characteristic basis vectors and frequency characteristic basis vectors according to the operating frequency. For the standard microwave signal of each operating frequency, extract the projection coefficient on the time characteristic basis vector as the time domain characteristic, and the projection coefficient on the frequency characteristic basis vector as the frequency domain characteristic to generate the standard signal characteristic vector of each operating frequency; Associate the standard signal characteristic vectors of all operating frequencies with the corresponding transmitter identifiers and communication frequency data to construct a signal characteristic database, where each entry includes a transmitter identifier, a communication frequency, a time domain characteristic, a frequency domain characteristic, and an energy weight.

[0009] In this solution, the hybrid multi-frequency microwave signal in the target pipeline detection area is obtained, and the hybrid multi-frequency microwave signal is decomposed into single-frequency signal streams according to the signal characteristic database, and the single-frequency signal stream information is determined, specifically: Obtain the mixed multi-frequency microwave signal of the target pipeline detection area, use a sliding time window to intercept signal segments from the mixed multi-frequency microwave signal and perform zero-mean normalization to generate a normalized mixed signal matrix; Construct a demixing model based on the independent component analysis algorithm, input the mixed signal matrix into the demixing model, calculate the separation weight matrix of independent components through the non-Gaussianity maximization criterion, and perform a decomposition operation on the normalized mixed signal matrix according to the separation weight matrix to obtain a demixing matrix; Decompose the multi-frequency microwave signal into independent single-frequency signal streams according to the demixing matrix, extract time-frequency domain features of the separated single-frequency signals, calculate the time-domain envelope features and frequency-domain power spectrum features of each single-frequency signal, and generate a signal feature vector to be matched; Perform a correlation analysis on the signal feature vector to be matched and the standard signal feature vector in the signal feature database. If the correlation coefficient between the time-domain features of the single-frequency signal and the standard signal time-domain features is greater than the set threshold and the similarity of the frequency-domain feature energy distribution is higher than the matching threshold, then label this single-frequency signal as a valid single-frequency signal stream, and associate the corresponding transmitter identification and communication frequency data; If the correlation coefficient of the time-domain features of the single-frequency signal is less than the set threshold or the similarity of the frequency-domain energy distribution is lower than the matching threshold, then label the single-frequency signal as an abnormal signal stream, perform wavelet transform analysis on the abnormal signal stream and extract multi-scale energy distribution features. If the frequency band width corresponding to the maximum energy scale exceeds the preset range, it is determined as an environmental interference signal and excluded. If the energy distribution shows narrowband characteristics, it is determined as an unregistered signal source, extract its signal features and update them to the signal feature database; After all single-frequency signal streams are matched with the standard signal feature vectors in the signal feature database, output the transmitter identification and communication frequency of each valid single-frequency signal stream to obtain the single-frequency signal stream information.

[0010] In this solution, the multi-frequency signal transmitter and receiver are matched for data channels according to the single-frequency signal stream information, and data connection is performed according to the matched data channels. Specifically: Obtain the current available frequency list of the receiver and the signal energy weights corresponding to each receiving frequency, and align the transmitter communication frequency with the available frequencies of the receiver according to the single-frequency signal stream information; When the energy weight of the transmitter communication frequency is higher than the energy weight threshold of the corresponding frequency point in the receiver's available frequency list, establish a data channel between the transmitter and the receiver at this frequency and execute a two-way handshake protocol. If the handshake protocol response time is less than the preset time delay and the check code matches successfully, it is confirmed that the data connection is valid; When there is no corresponding frequency point for the transmitter communication frequency in the receiver's available frequency list, switch to the next frequency point in the receiver's available frequency list and re-execute the frequency point alignment operation until a matching frequency point is found; When the communication frequencies of multiple transmitting ends match the frequency of the same receiving end, time-division multiplexing channels are allocated according to the difference degree of the time-domain characteristics of the signals of each transmitting end. When the difference degree of the time-domain characteristics is lower than the multiplexing threshold and the orthogonality of the signal energy distribution meets the preset conditions, orthogonal subcarrier frequency bands are allocated to each transmitting end to form independent data channels; The multi-frequency signal transmitting end and the receiving end are data-linked according to the data channels or independent data channels.

[0011] In this solution, if there is a terminal with a failed data link, the influence data of the pipeline environment characteristics on the signal frequency drift is obtained, and a frequency drift compensation model is constructed according to the influence data. Specifically: Obtain the data link situation of the multi-frequency communication detection terminals in the target site. If there is a terminal with a failed data link, obtain the transmitted signal data and received signal data of the multi-frequency communication detection terminals detecting pipelines with different environmental characteristics, compare the transmitted signal and the received signal, judge the frequency difference between the received signal and the transmitted signal, and determine the signal frequency drift situation of the received signal under different pipeline environmental characteristics according to the frequency difference; Construct an environmental characteristic-frequency drift matrix according to the signal frequency drift situation of the received signal under different pipeline environmental characteristics, perform a correlation analysis on the environmental characteristic-frequency drift matrix, determine the influence of the pipeline environmental characteristics on the signal frequency drift, and obtain the influence data; Determine the damage items and damage degrees of the frequency drift caused by each pipeline environmental characteristic to the received signal according to the influence data, and determine the frequency repair compensation parameters for the frequency drift of the received signal according to the damage items and damage degrees; Construct a frequency drift compensation model based on the decision tree algorithm. Respectively, the pipeline environmental characteristics and the frequency repair compensation parameters are used as the input feature vector and output feature vector of the model, and the frequency repair compensation parameters of each environmental characteristic are imported into the frequency drift compensation model for training; Recursively construct the decision tree branch nodes. Calculate the variance of the frequency compensation parameters under the division conditions of different pipeline environmental characteristics at each node, and select the feature division threshold corresponding to the minimum variance as the node splitting condition to generate the decision tree structure layer by layer; Prune and optimize the initial decision tree through the cross-validation method to eliminate overfitting branches. Extract the mapping rules between the main pipeline environmental characteristics and the frequency repair compensation parameters according to the pruned decision tree to form a frequency drift compensation rule library. Use the frequency drift compensation rule library as the data output basis of the frequency drift compensation model to obtain the trained frequency drift compensation model.

[0012] In this solution, frequency compensation is performed on the decomposed single-frequency signal stream according to the environmental information of the pipeline detected by the data link failure terminal and the frequency drift compensation model, and the transmitter and the receiver are reconnected according to the frequency-compensated single-frequency signal stream. Specifically: Obtain the environmental information of the pipeline detected by the data link failure terminal, import the environmental information into the frequency drift compensation model, and output the frequency drift compensation parameters of the single-frequency signal stream of the data link failure terminal; Perform frequency compensation on the decomposed single-frequency signal stream according to the frequency drift compensation parameters, and reconnect the transmitter and the receiver according to the frequency-compensated single-frequency signal stream.

[0013] The second aspect of the present invention also provides a multi-frequency communication detection terminal control system for pipeline detection. The system includes: a memory and a processor. The memory includes a multi-frequency communication detection terminal control method program for pipeline detection. When the multi-frequency communication detection terminal control method program for pipeline detection is executed by the processor, the following steps are implemented: Extract the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency, and construct a signal characteristic database; Obtain the mixed multi-frequency microwave signals in the target pipeline detection area, decompose the mixed multi-frequency microwave signals into single-frequency signal streams according to the signal characteristic database, and determine the single-frequency signal stream information; Match the data channels between the multi-frequency signal transmitter and the receiver according to the single-frequency signal stream information, and perform data link according to the matched data channels; If there is a data link failure terminal, obtain the influence data of the pipeline environmental characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; Perform frequency compensation on the decomposed single-frequency signal stream according to the environmental information of the pipeline detected by the data link failure terminal and the frequency drift compensation model, and reconnect the transmitter and the receiver according to the frequency-compensated single-frequency signal stream.

[0014] The present invention discloses a control method for a multi - frequency communication detection terminal used for pipeline detection. This method constructs a standard microwave signal feature database of the multi - frequency communication detection terminal, performs feature matching and decomposition on the mixed multi - frequency microwave signals in the target pipeline area, and realizes the precise separation of single - frequency signal streams. Based on the information of the decomposed single - frequency signal streams, a dynamic matching mechanism for the data channels between the transmitter and the receiver is established, the influence of frequency drift is modeled in combination with the pipeline environment characteristics, and a frequency - drift compensation model with environmental adaptability is constructed. When a communication link anomaly occurs, the signal stream is adaptively corrected through real - time environmental data acquisition and frequency compensation algorithms to complete the rapid reconstruction of the communication link. The present invention effectively solves the communication stability problem caused by frequency drift in complex pipeline environments, and significantly improves the reliability and detection accuracy of the pipeline detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The flowchart of a control method for a multi - frequency communication detection terminal used for pipeline detection according to the present invention is shown; Figure 2 The flowchart of data linking according to the matched data channels of the present invention is shown; Figure 3 The flowchart of reconnecting the transmitter and the receiver of the present invention is shown; Figure 4 The block diagram of a control system for a multi - frequency communication detection terminal used for pipeline detection according to the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] In order to more clearly understand the above - mentioned objects, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0017] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0018] Figure 1 The flowchart of a control method for a multi - frequency communication detection terminal used for pipeline detection according to the present invention is shown.

[0019] As Figure 1 shown, in the first aspect of the present invention, a control method for a multi - frequency communication detection terminal used for pipeline detection is provided, including: S102, extracting the signal features of the standard microwave signals of the multi - frequency communication detection terminal at each operating frequency, and constructing a signal feature database; S104. Obtain the mixed multi - frequency microwave signal in the target pipeline detection area, decompose the mixed multi - frequency microwave signal into single - frequency signal streams according to the signal feature database, and determine the single - frequency signal stream information; S106. Match the data channels between the multi - frequency signal transmitter and receiver according to the single - frequency signal stream information, and establish a data link based on the matched data channels; S108. If there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; S110. Perform frequency compensation on the decomposed single - frequency signal streams according to the pipeline environment information and the frequency drift compensation model of the terminal with a failed data link, and reconnect the transmitter and receiver according to the frequency - compensated single - frequency signal streams.

[0020] It should be noted that by extracting the standard microwave signal characteristics to construct a database, after obtaining the mixed multi - frequency signal, based on the database, the single - frequency signal stream information is decomposed and determined, effectively avoiding signal aliasing interference and ensuring data integrity. By matching the transmitter and receiver to establish a data link, the communication resource allocation is optimized to ensure transmission stability. For the terminal with a failed data link, analyze the influence of the pipeline environment and construct a frequency drift compensation model to dynamically adapt to environmental interference and accurately predict the drift law. Finally, repair the communication interruption according to the compensation model, enhance the robustness of the terminal, and ensure the continuity of detection. This method realizes the efficient separation, precise matching and adaptive compensation of multi - frequency signals, significantly improving the communication quality and detection efficiency in complex pipeline environments.

[0021] According to an embodiment of the present invention, the extraction of the signal characteristics of the standard microwave signals of the multi - frequency communication detection terminal at each operating frequency and the construction of a signal feature database are specifically as follows: Collect the standard microwave signals transmitted by the multi - frequency communication detection terminal at each operating frequency in time series to obtain an original signal matrix, where each row represents a sampling time point and each column represents the sampling data of an operating frequency; Perform centering processing on the original signal matrix, calculate the mean value of the data in each frequency channel, and subtract the mean value of the corresponding channel from each element of the original signal matrix to obtain a centered signal matrix; Introduce the singular value decomposition algorithm, and decompose the centered signal matrix into the product form of a left singular vector matrix, a singular value diagonal matrix and a right singular vector matrix according to the singular value decomposition algorithm. The column vectors of the left singular vector matrix represent the signal feature patterns in the time dimension, the row vectors of the right singular vector matrix represent the signal feature patterns in the frequency dimension, and the diagonal elements of the singular value diagonal matrix represent the energy weights of each feature pattern; According to the singular value magnitudes of the singular value diagonal matrix, select the signal feature patterns corresponding to the top K largest singular values. Take the first K columns of the left singular vector matrix as the time feature basis vectors and the first K rows of the right singular vector matrix as the frequency feature basis vectors to construct a signal feature projection space after dimensionality reduction. Classify and store the time feature basis vectors and frequency feature basis vectors according to the operating frequency. For the standard microwave signals at each operating frequency, extract the projection coefficients on the time feature basis vectors as time domain features and the projection coefficients on the frequency feature basis vectors as frequency domain features to generate standard signal feature vectors for each operating frequency. Associate the standard signal feature vectors of all operating frequencies with the corresponding transmitter identifiers and communication frequency data to construct a signal feature database, where each entry includes the transmitter identifier, communication frequency, time domain features, frequency domain features, and energy weights.

[0022] It should be noted that the singular value decomposition algorithm is introduced. By calculating the singular values of the signal matrix, the energy distribution characteristics of different frequency signals can be automatically identified, realizing efficient dimensionality reduction processing of multi-frequency signals and significantly reducing the data storage and calculation burden. Taking the decomposed left singular vectors as time feature basis vectors and the right singular vectors as frequency feature basis vectors can accurately characterize the variation law of the signal in the time-frequency domain. By extracting the projection coefficients of each operating frequency on the feature basis vectors to generate standard signal feature vectors, a signal feature database with high discrimination can be established to ensure the uniqueness and stability of the feature representation of different frequency signals. Associating and storing the feature vectors with the transmitter identifier and communication frequency forms a complete signal feature database. The energy weight is the value of the diagonal elements in the singular value diagonal matrix obtained by singular value decomposition (SVD), which quantifies the relative importance of the signal feature pattern in the overall signal energy. In signal processing, larger singular values correspond to stronger and more representative feature components in the signal, while smaller singular values usually reflect noise or secondary information.

[0023] According to the embodiments of the present invention, obtaining the mixed multi-frequency microwave signal in the detection area of the target pipeline, decomposing the mixed multi-frequency microwave signal into single-frequency signal streams according to the signal feature database, and determining the single-frequency signal stream information specifically includes: Obtain the mixed multi-frequency microwave signal in the detection area of the target pipeline, intercept signal segments of the mixed multi-frequency microwave signal using a sliding time window and perform zero-mean normalization to generate a standardized mixed signal matrix. Construct a demixing model based on the independent component analysis algorithm, input the standardized mixed signal matrix into the demixing model, calculate the separation weight matrix of the independent components according to the non-Gaussianity maximization criterion, and perform a decomposition operation on the standardized mixed signal matrix according to the separation weight matrix to obtain a demixing matrix. The multi - frequency microwave signal is decomposed into independent single - frequency signal streams according to the demixing matrix, and time - frequency domain feature extraction is performed on the separated single - frequency signals. The time - domain envelope feature and frequency - domain power spectrum feature of each single - frequency signal are calculated to generate a signal feature vector to be matched. It should be noted that in traditional pipeline detection terminals, the transmitter and receiver communicate only through a single frequency. When two sets of devices work simultaneously, co - frequency interference will occur, and the receiver cannot distinguish which transmitter emits the microwave signal. Therefore, by acquiring the mixed multi - frequency microwave signal at the receiver, the mixed multi - frequency microwave signal is decomposed based on the independent component analysis algorithm. Based on the non - Gaussian feature of the signal, each frequency - band component in the mixed signal is accurately separated by calculating the separation weight matrix, enabling the receiver to accurately distinguish the microwave signals emitted by different transmitters. The decomposed independent single - frequency signal streams retain the complete features of the original signal.

[0024] Perform a correlation analysis on the signal feature vector to be matched and the standard signal feature vector in the signal feature database. If the correlation coefficient between the time - domain feature of the single - frequency signal and the time - domain feature of the standard signal is greater than the set threshold and the similarity of the frequency - domain feature energy distribution is higher than the matching threshold, then the single - frequency signal is calibrated as a valid single - frequency signal stream, and the corresponding transmitter identifier and communication frequency data are associated. If the correlation coefficient of the time - domain feature of the single - frequency signal is less than the set threshold or the similarity of the frequency - domain energy distribution is lower than the matching threshold, then the single - frequency signal is calibrated as an abnormal signal stream. Perform wavelet transform analysis on the abnormal signal stream and extract the multi - scale energy distribution feature. If the frequency - band width corresponding to the maximum energy scale exceeds the preset range, it is determined as an environmental interference signal and excluded. If the energy distribution shows a narrow - band characteristic, it is determined as an unregistered signal source, and its signal features are extracted and updated to the signal feature database. When the matching of all single - frequency signal streams with the standard signal feature vector in the signal feature database is completed, the transmitter identifier and communication frequency of each valid single - frequency signal stream are output to obtain the single - frequency signal stream information.

[0025] It should be noted that by performing correlation analysis on the signal feature vector to be matched and the standard features in the database, when the correlation coefficient of the time-domain features of the signal meets the standard and the frequency-domain energy distribution matches, the system can accurately determine that the signal is a valid single-frequency signal stream, thus avoiding misjudging interference signals or noise as valid signals. By associating the transmitter identification and communication frequency data, accurate tracing of multi-terminal signals is achieved, ensuring that each received signal can be correctly mapped to its transmitter source. When the correlation coefficient of the time-domain features of the single-frequency signal is insufficient or the frequency-domain similarity is low, it indicates that the signal may be interfered or belongs to an unregistered device. At this time, the system automatically starts the abnormal signal analysis process. Through multi-scale analysis of wavelet transform, the time-frequency characteristics of the signal can be deeply analyzed: if the signal energy distribution shows broadband characteristics, it indicates environmental noise or burst interference, and the system will filter it out to avoid mis-matching; if it shows narrowband characteristics, it is identified as a new device signal, and the system will intelligently extract its features and update the database to achieve the adaptive expansion ability of the system. This mechanism not only ensures the accurate identification of valid signals but also dynamically improves the signal feature library, enabling the system to have the ability of continuous optimization, effectively solving the problem of performance degradation of traditional methods in the face of unknown signals or strong interference, and significantly improving the reliability and adaptability of the pipeline detection system in complex environments.

[0026] Figure 2 The flowchart of data link according to the matching data channels of the present invention is shown.

[0027] According to an embodiment of the present invention, the data channel matching between the multi-frequency signal transmitter and the receiver according to the single-frequency signal stream information and the data link according to the matched data channel are specifically as follows: S202, obtain the current available frequency list of the receiver and the signal energy weights corresponding to each received frequency, and align the transmitter communication frequency with the available frequencies of the receiver according to the single-frequency signal stream information; S204, when the energy weight of the transmitter communication frequency is higher than the energy weight threshold of the corresponding frequency point in the available frequency list of the receiver, establish a data channel between the transmitter and the receiver at this frequency and execute the two-way handshake protocol. If the response time of the handshake protocol is less than the preset time delay and the check code matches successfully, it is confirmed that the data link is valid; S206, when there is no corresponding frequency point for the transmitter communication frequency in the available frequency list of the receiver, switch to the next frequency point in the available frequency list of the receiver and re-execute the frequency point alignment operation until a matching frequency point is found; S208, when multiple transmitter communication frequencies match the same receiver frequency, allocate time-division multiplexing channels according to the time-domain feature difference degree of each transmitter signal. When the time-domain feature difference degree is lower than the multiplexing threshold and the orthogonality of the signal energy distribution meets the preset conditions, allocate orthogonal subcarrier frequency bands for each transmitter to form independent data channels; S210. Data-link the multi-frequency signal transmitter and receiver according to the data channel or the independent data channel.

[0028] It should be noted that when obtaining the available frequency list of the receiver and the corresponding energy weights, when performing frequency alignment, if the frequency energy weight of the transmitter is higher than the receiver threshold, it indicates that the signal quality of this frequency point is good. At this time, a data channel is established and the connection reliability is verified through a two-way handshake protocol to ensure that the communication link meets the requirements of real-time and accuracy. When the frequency of the transmitter has no corresponding frequency point in the receiver list, the system automatically switches to the next available frequency point for re-matching. This mechanism solves the problem of connection failure in traditional methods when the frequency point resources are insufficient. In the special case where multiple transmitters need to share the same receiving frequency, the system first evaluates the difference degree of the signal time-domain characteristics. If the difference is insufficient, it further detects the orthogonality of the energy distribution. By dynamically allocating time-division multiplexing channels or orthogonal subcarrier frequency bands, it not only avoids co-frequency interference but also maximizes the utilization of limited spectrum resources. The whole process realizes full-scenario coverage from simple frequency point matching to complex multiple access, effectively solves the problems of spectrum resource competition and signal conflict caused by the changing environment in pipeline detection, and significantly improves the communication reliability and spectrum utilization rate of multi-terminal collaborative work. The preset condition is the set preset value range.

[0029] According to an embodiment of the present invention, if there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data. Specifically: Obtain the data link situation of the multi-frequency communication detection terminals in the target site. If there is a terminal with a failed data link, obtain the transmitted signal data and received signal data of the multi-frequency communication detection terminals detecting pipelines with different environmental characteristics, compare the transmitted signal and the received signal, judge the frequency difference between the received signal and the transmitted signal, and determine the signal frequency drift situation of the received signal under different pipeline environmental characteristics according to the frequency difference; Construct an environmental characteristic-frequency drift matrix according to the signal frequency drift situation of the received signal under different pipeline environmental characteristics, perform a correlation analysis on the environmental characteristic-frequency drift matrix, determine the influence of the pipeline environmental characteristics on the signal frequency drift, and obtain the influence data; Determine the damage items and damage degrees of the frequency drift caused by each pipeline environmental characteristic to the received signal according to the influence data, and determine the frequency repair compensation parameters for the frequency drift of the received signal according to the damage items and damage degrees; Construct a frequency drift compensation model based on the decision tree algorithm, use the pipeline environmental characteristics and the frequency repair compensation parameters as the input feature vector and output feature vector of the model respectively, and import the frequency repair compensation parameters of each environmental characteristic into the frequency drift compensation model for training; Recursively construct the decision tree branch nodes, calculate the variance of the frequency compensation parameters under different pipeline environment feature partitioning conditions at each node, select the feature partitioning threshold corresponding to the minimum variance as the node splitting condition, and generate the decision tree structure layer by layer; Prune and optimize the initial decision tree through the cross-validation method to eliminate overfitting branches. Extract the mapping rule between the main features of the pipeline environment and the frequency repair compensation parameters according to the pruned decision tree to form a frequency drift compensation rule library. Use the frequency drift compensation rule library as the data output basis of the frequency drift compensation model to obtain the trained frequency drift compensation model.

[0030] It should be noted that in a complex pipeline detection environment, factors such as metal materials, fluid media, and structural deformation will cause different degrees of frequency drift of microwave signals, resulting in unstable or even interrupted communication links. By using the decision tree algorithm to construct an intelligent frequency drift compensation model, first collect the signal transmission data under different pipeline environments, establish an environmental feature - frequency drift matrix, and accurately quantify the influence law of various environmental factors on frequency drift; then recursively partition the feature space based on the decision tree, select the optimal splitting threshold by minimizing the variance of the compensation parameters, and construct a tree-shaped compensation rule with strong interpretability; finally, prune and optimize the model structure through cross-validation to eliminate the risk of overfitting and form a concise and reliable compensation rule library. This model can adaptively identify the main features of the pipeline environment, intelligently match the optimal compensation parameters, achieve accurate frequency correction under different environments, effectively solve the problems of insufficient compensation accuracy and poor adaptability of traditional methods, and significantly improve the stability and reliability of multi-frequency communication links in complex pipeline environments; the pipeline environment features include pipeline material, pipe diameter size, internal medium type, temperature, humidity, degree of structural deformation, and corrosion condition; the damage items include items such as the waveform, spectrum broadening, phase, amplitude, and signal-to-noise ratio of the signal.

[0031] Figure 3 The flowchart showing the reconnection operation of the transmitter and receiver in the present invention is shown.

[0032] According to an embodiment of the present invention, frequency compensation is performed on the decomposed single-frequency signal stream according to the environmental information of the pipeline detected by the data link failure terminal and the frequency drift compensation model, and the transmitter and receiver are reconnected according to the frequency-compensated single-frequency signal stream. Specifically: S302, Obtain the environmental information of the pipeline detected by the data link failure terminal, import the environmental information into the frequency drift compensation model, and output the frequency drift compensation parameters of the single-frequency signal stream of the data link failure terminal; S304, Perform frequency compensation on the decomposed single-frequency signal stream according to the frequency drift compensation parameters, and reconnect the transmitter and receiver according to the frequency-compensated single-frequency signal stream.

[0033] It should be noted that when the data link fails, by obtaining the current pipeline environment information and inputting it into a pre-trained frequency drift compensation model, the optimal compensation parameters for this environment are intelligently output. Based on these parameters, precise frequency compensation is performed on the single-frequency signal stream, which can effectively correct damages such as signal waveform distortion and spectrum offset caused by the pipeline environment, and restore the original characteristics of the signal. The compensated signal is rematched with the frequency characteristics of the receiving end, enabling the transmitting end and the receiving end to reconstruct a stable and reliable communication link. This process realizes environment-adaptive signal repair, solves the communication failure problem caused by frequency drift in complex pipeline environments by traditional methods, and significantly improves the communication success rate and stability of the pipeline detection system in harsh environments.

[0034] According to an embodiment of the present invention, it further includes: Perform frequency point analysis on the mixed multi-frequency microwave signal, calculate the frequency point spacing, judge the frequency point density according to the frequency point spacing, and label the frequency points with a density greater than a preset value as target frequency points; Extract the frequency feature basis vector and time feature basis vector corresponding to the target frequency points from the standard signal feature database, and use the frequency feature basis vector as a priori constraint conditions to construct a demixing model of the independent component analysis algorithm; Use a sliding time window to intercept signal segments of the mixed multi-frequency microwave signal and perform zero-mean normalization to generate a second normalized mixed signal matrix, and project the second normalized mixed signal matrix onto the signal subspace spanned by the frequency feature basis vector; Calculate an optimized separation weight matrix based on the non-Gaussianity maximization criterion in the signal subspace, and use the separation weight matrix to perform blind source separation operations on the projected mixed signal to obtain an initial demixed signal; Back-project the initial demixed signal to the original signal space and perform time-domain constraint matching with the time feature basis vector, and correct the orthogonality deviation of the separation weight matrix through an iterative optimization algorithm; After the correction is completed, output the corrected demixed signal.

[0035] It should be noted that, in view of the communication failure problem caused by the mutual interference of high-density multi-frequency signals in pipeline detection, when multiple detection terminals work simultaneously in a narrow pipe section, the traditional blind source separation algorithm fails in the scenario where the frequency point spacing of the mixed signal is too small (less than 0.5 MHz). Through the collaborative processing mechanism of dynamic determination of frequency point density and signal feature database, accurate signal separation in a complex electromagnetic environment is achieved. This solution first calculates the frequency point spacing and classifies the density to accurately lock the target frequency points in the high-frequency interference area. Combining with the pre-stored standard signal feature database, the time-frequency domain feature basis vectors corresponding to the frequency points are extracted to construct a prior constraint demixing model. After projecting the mixed signal into the feature subspace, constrained blind source separation is implemented, effectively overcoming the separation ambiguity defect of traditional independent component analysis when the frequency points are too dense. The orthogonality deviation is corrected by back-projection and time-domain constraint matching of the time feature basis vectors, ensuring the integrity of the time-frequency structure of the demixed signal. The finally output corrected demixed signal not only retains the modulation features of the original signal, but also eliminates the pseudo-signal components introduced by environmental interference through the dynamic similarity matching and secondary screening mechanism, significantly improving the signal separation accuracy in the dense frequency point scenario and the anti-interference ability of the communication link.

[0036] Figure 4 Fig. shows a block diagram of a multi-frequency communication detection terminal control system for pipeline detection according to the present invention.

[0037] In the second aspect of the present invention, a multi-frequency communication detection terminal control system 4 for pipeline detection is further provided. The system includes: a memory 41 and a processor 42. The memory includes a program for the control method of the multi-frequency communication detection terminal for pipeline detection. When the program for the control method of the multi-frequency communication detection terminal for pipeline detection is executed by the processor, the following steps are implemented: Extract the signal features of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency, and construct a signal feature database; Obtain the mixed multi-frequency microwave signal in the target pipeline detection area, decompose the mixed multi-frequency microwave signal into single-frequency signal streams according to the signal feature database, and determine the single-frequency signal stream information; Match the data channels of the multi-frequency signal transmitter and receiver according to the single-frequency signal stream information, and establish a data link according to the matched data channels; If there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; Perform frequency compensation on the decomposed single-frequency signal streams according to the pipeline environment information and frequency drift compensation model of the terminal with the failed data link for detecting the pipeline, and reconnect the transmitter and receiver according to the frequency-compensated single-frequency signal streams.

[0038] The present invention discloses a control method for a multi-frequency communication detection terminal for pipeline detection. The method realizes the precise separation of single-frequency signal streams by constructing a standard microwave signal feature database of the multi-frequency communication detection terminal, performing feature matching and decomposition on the mixed multi-frequency microwave signals in the target pipeline area. A dynamic matching mechanism for the data channels between the transmitter and the receiver is established based on the information of the decomposed single-frequency signal streams, and the influence of frequency drift is modeled in combination with the pipeline environment characteristics to construct a frequency drift compensation model with environmental adaptability. When a communication link anomaly occurs, the signal stream is adaptively corrected through real-time environmental data acquisition and frequency compensation algorithms to complete the rapid reconstruction of the communication link. The present invention effectively solves the communication stability problem caused by frequency drift in a complex pipeline environment, and significantly improves the reliability and detection accuracy of the pipeline detection system.

[0039] In several embodiments provided by the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined, or can be integrated into another system, or some features can be ignored, or not executed. In addition, the couplings, direct couplings, or communication connections between the various components shown or discussed may be through some interfaces, and the indirect couplings or communication connections of devices or units may be electrical, mechanical, or other forms.

[0040] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units; they may be located in one place or distributed to multiple network units; some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0041] In addition, in each embodiment of the present invention, the various functional units may all be integrated in one processing unit, or each unit may be separately taken as a unit, or two or more units may be integrated in one unit; the above-mentioned integrated units may be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0042] Those of ordinary skill in the art can understand that all or part of the steps to implement the above method embodiments can be completed by hardware related to program instructions. The foregoing program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps including those of the above method embodiments; and the foregoing storage medium includes: various media that can store program codes such as removable storage devices, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs.

[0043] Alternatively, if the above integrated units of the present invention are implemented in the form of software function modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of the embodiments of the present invention, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the methods described in the various embodiments of the present invention. And the foregoing storage medium includes: various media that can store program codes such as removable storage devices, ROM, RAM, magnetic disks, or optical discs.

[0044] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A control method for a multi-frequency communication detection terminal used for pipeline detection, characterized in that, Including the following steps: Extract the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency, and construct a signal characteristic database; Obtain the mixed multi-frequency microwave signals in the target pipeline detection area, decompose the mixed multi-frequency microwave signals into single-frequency signal streams according to the signal characteristic database, and determine the single-frequency signal stream information; Match the data channels between the multi-frequency signal transmitter and the receiver according to the single-frequency signal stream information, and perform data link according to the matched data channels; If there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; Perform frequency compensation on the decomposed single-frequency signal streams according to the environment information of the pipeline detected by the terminal with a failed data link and the frequency drift compensation model, and reconnect the transmitter and the receiver according to the single-frequency signal streams after frequency compensation.

2. The control method of a multi-frequency communication detection terminal for pipeline detection according to claim 1, characterized in that The extraction of the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency and the construction of the signal characteristic database are specifically as follows: Collect the standard microwave signals transmitted by the multi-frequency communication detection terminal at each operating frequency in time series to obtain an original signal matrix, where each row represents a sampling time point and each column represents the sampling data of an operating frequency; Perform centering processing on the original signal matrix, calculate the mean value of the data in each frequency channel, subtract the mean value of the corresponding channel from each element of the original signal matrix to obtain a centered signal matrix; Introduce the singular value decomposition algorithm, and decompose the centered signal matrix into the product form of a left singular vector matrix, a singular value diagonal matrix, and a right singular vector matrix according to the singular value decomposition algorithm. The column vectors of the left singular vector matrix represent the signal characteristic patterns in the time dimension, the row vectors of the right singular vector matrix represent the signal characteristic patterns in the frequency dimension, and the diagonal elements of the singular value diagonal matrix represent the energy weights of each characteristic pattern; According to the singular values of the singular value diagonal matrix, select the signal characteristic patterns corresponding to the first K largest singular values, use the first K columns of the left singular vector matrix as the time characteristic basis vectors, and the first K rows of the right singular vector matrix as the frequency characteristic basis vectors to construct a reduced-dimensional signal characteristic projection space; Classify and store the time characteristic basis vectors and frequency characteristic basis vectors according to the operating frequency. For the standard microwave signals of each operating frequency, extract the projection coefficients on the time characteristic basis vectors as time domain characteristics, and the projection coefficients on the frequency characteristic basis vectors as frequency domain characteristics to generate the standard signal characteristic vectors of each operating frequency; Associate the standard signal characteristic vectors of all operating frequencies with the corresponding transmitter identifiers and communication frequency data to construct a signal characteristic database, where each entry contains the transmitter identifier, communication frequency, time domain characteristics, frequency domain characteristics, and energy weights.

3. A multi-frequency communication detection terminal control method for pipeline detection according to claim 1, characterized in that The obtaining of the mixed multi-frequency microwave signals in the target pipeline detection area, the decomposition of the mixed multi-frequency microwave signals into single-frequency signal streams according to the signal characteristic database, and the determination of the single-frequency signal stream information are specifically as follows: Obtain the mixed multi - frequency microwave signal in the detection area of the target pipeline. Use a sliding time window to intercept signal segments from the mixed multi - frequency microwave signal and perform zero - mean normalization to generate a normalized mixed signal matrix; Based on the independent component analysis algorithm, construct a demixing model. Input the mixed signal matrix into the demixing model, calculate the separation weight matrix of independent components through the non - Gaussianity maximization criterion, and perform a decomposition operation on the normalized mixed signal matrix according to the separation weight matrix to obtain a demixing matrix; Decompose the multi - frequency microwave signal into independent single - frequency signal streams according to the demixing matrix. Extract time - frequency domain features from the separated single - frequency signals, calculate the time - domain envelope feature and frequency - domain power spectrum feature of each single - frequency signal, and generate a signal feature vector to be matched; Perform a correlation analysis between the signal feature vector to be matched and the standard signal feature vector in the signal feature database. If the correlation coefficient between the time - domain feature of the single - frequency signal and the time - domain feature of the standard signal is greater than the set threshold and the similarity of the frequency - domain feature energy distribution is higher than the matching threshold, then label this single - frequency signal as a valid single - frequency signal stream, and associate the corresponding transmitter identifier and communication frequency data; If the correlation coefficient of the time - domain feature of the single - frequency signal is less than the set threshold or the similarity of the frequency - domain energy distribution is lower than the matching threshold, then label the single - frequency signal as an abnormal signal stream. Perform wavelet transform analysis on the abnormal signal stream and extract the multi - scale energy distribution feature. If the frequency - band width corresponding to the maximum energy scale exceeds the preset range, it is determined as an environmental interference signal and excluded. If the energy distribution shows a narrow - band characteristic, it is determined as an unregistered signal source, and its signal features are extracted and updated to the signal feature database; When the matching of all single - frequency signal streams with the standard signal feature vectors in the signal feature database is completed, output the transmitter identifier and communication frequency of each valid single - frequency signal stream to obtain the single - frequency signal stream information.

4. A control method for a multi-frequency communication detection terminal for pipeline detection according to claim 1, characterized in that, Match the data channels between the multi - frequency signal transmitter and the receiver according to the single - frequency signal stream information, and perform data connection according to the matched data channels. Specifically: Obtain the current available frequency list at the receiver and the signal energy weights corresponding to each receiving frequency. Align the transmitter communication frequency with the available frequencies at the receiver according to the single - frequency signal stream information; When the energy weight of the transmitter communication frequency is higher than the energy weight threshold of the corresponding frequency point in the receiver's available frequency list, establish a data channel between the transmitter and the receiver at this frequency and execute a two - way handshake protocol. If the handshake protocol response time is less than the preset time delay and the check code matches successfully, confirm that the data connection is valid; When there is no corresponding frequency point for the transmitter communication frequency in the receiver's available frequency list, switch to the next frequency point in the receiver's available frequency list and re - execute the frequency - point alignment operation until a matching frequency point is found; If multiple transmitter communication frequencies match the same receiver frequency, allocate time - division multiplexing channels according to the time - domain feature difference degree of each transmitter signal. When the time - domain feature difference degree is lower than the multiplexing threshold and the orthogonality of the signal energy distribution meets the preset conditions, allocate orthogonal sub - carrier frequency bands for each transmitter to form independent data channels; Perform data connection between the multi - frequency signal transmitter and the receiver according to the data channel or independent data channels.

5. A multi-frequency communication detection terminal control method for pipeline detection according to claim 1, characterized in that, If there is a terminal with a failed data link, obtain the data on the influence of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model based on the influence data. Specifically: Obtain the data link status of the multi-frequency communication detection terminals in the target location. If there is a terminal with a failed data link, obtain the transmitted signal data and received signal data of the multi-frequency communication detection terminals for detecting pipelines with different environmental characteristics, compare the transmitted signal and the received signal, judge the frequency difference between the received signal and the transmitted signal, and determine the signal frequency drift of the received signal under different pipeline environmental characteristics according to the frequency difference; Construct an environmental characteristic-frequency drift matrix based on the signal frequency drift of the received signal under different pipeline environmental characteristics, perform a correlation analysis on the environmental characteristic-frequency drift matrix, determine the influence of the pipeline environmental characteristics on the signal frequency drift, and obtain the influence data; Determine the damage items and damage degrees of the frequency drift caused by each pipeline environmental characteristic to the received signal according to the influence data, and determine the frequency repair compensation parameters for the frequency drift of the received signal according to the damage items and damage degrees; Construct a frequency drift compensation model based on the decision tree algorithm. Respectively use the pipeline environmental characteristics and the frequency repair compensation parameters as the input feature vector and output feature vector of the model, and import the frequency repair compensation parameters of each environmental characteristic into the frequency drift compensation model for training; Recursively construct the decision tree branch nodes. Calculate the variance of the frequency compensation parameters under the division conditions of different pipeline environmental characteristics at each node, and select the feature division threshold corresponding to the minimum variance as the node splitting condition to generate the decision tree structure layer by layer; Prune and optimize the initial decision tree through the cross-validation method to eliminate overfitting branches. Extract the mapping rule between the main pipeline environmental characteristics and the frequency repair compensation parameters according to the pruned decision tree to form a frequency drift compensation rule library, and use the frequency drift compensation rule library as the data output basis of the frequency drift compensation model to obtain the trained frequency drift compensation model.

6. The control method of a multi-frequency communication detection terminal for pipeline detection according to claim 1, characterized in that, Perform frequency compensation on the decomposed single-frequency signal stream according to the environmental information of the pipeline detected by the terminal with a failed data link and the frequency drift compensation model, and reconnect the transmitter and the receiver according to the frequency-compensated single-frequency signal stream. Specifically: Obtain the environmental information of the pipeline detected by the terminal with a failed data link, import the environmental information into the frequency drift compensation model, and output the frequency drift compensation parameters of the single-frequency signal stream of the terminal with a failed data link; Perform frequency compensation on the decomposed single-frequency signal stream according to the frequency drift compensation parameters, and reconnect the transmitter and the receiver according to the frequency-compensated single-frequency signal stream.

7. A multi-frequency communication detection terminal control system for pipeline detection, characterized in that, The multi-frequency communication detection terminal control system for pipeline detection includes a memory and a processor. The memory includes a multi-frequency communication detection terminal control method program for pipeline detection. When the multi-frequency communication detection terminal control method program for pipeline detection is executed by the processor, the following steps are implemented: Extract the signal characteristics of the standard microwave signals of the multi-frequency communication detection terminal at each operating frequency, and construct a signal characteristic database; Obtain the mixed multi-frequency microwave signals in the target pipeline detection area, decompose the mixed multi-frequency microwave signals into single-frequency signal streams according to the signal characteristic database, and determine the single-frequency signal stream information; Match the data channels between the multi-frequency signal transmitter and the receiver according to the single-frequency signal stream information, and perform data link according to the matched data channels; If there is a terminal with a failed data link, obtain the influence data of the pipeline environment characteristics on the signal frequency drift, and construct a frequency drift compensation model according to the influence data; Perform frequency compensation on the decomposed single-frequency signal stream according to the pipeline environment information and the frequency drift compensation model of the data link failure terminal, and reconnect the transmitter and the receiver according to the frequency-compensated single-frequency signal stream.

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