Satellite synchronous detection signal transmitting device and applying method for underwater large-burial-depth pipeline

Abstract

The invention discloses a satellite synchronous detection signal transmitting device and applying method for an underwater large-burial-depth pipeline, and relates to the technical field of satellite synchronous detection, and the satellite synchronous detection signal transmitting device comprises a low-frequency shear force sensing module, a near-resonance recognition modeling module, a target detuning adjustment module, a pre-distortion beam generation module, a leakage spectrum suppression module and a closed-loop adaptive control module. And the low-frequency shear force sensing module is used for constructing a low-frequency shear force real-time sensing link. According to the method, through low-frequency shear force sensing, parameterized structure modeling, damping and rigidity cooperative adjustment, predistortion beam control and leakage spectrum screening, real-time prediction and active suppression of the antenna resonance risk in the deep sea environment are achieved, and the pipeline positioning precision is guaranteed. By combining satellite positioning residual error and time delay drift feedback, closed-loop adaptive control is constructed, a driving structure and signal collaborative optimization are realized, anti-resonance and leakage suppression effects are kept for a long time, an unattended operation period is prolonged, and detection reliability and data validity are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite synchronous detection, in particular to a satellite synchronous detection signal emitting device for underwater deep buried pipeline and an application method thereof. BACKGROUND

[0002] The satellite synchronous detection signal emitting device for underwater deep buried pipeline is a special signal emitting device for non-contact positioning and state monitoring of buried pipeline in deep sea or deep buried geological environment. The device is usually composed of a pressure-resistant and corrosion-resistant shell, a deep water antenna assembly, a precise timing unit, a signal modulation and amplification circuit, and an energy supply system. Through the built-in high-precision timing chip, the device maintains time synchronization with the global satellite navigation system (such as GPS and Beidou), emits the modulated detection signal to the water surface or ground in a specific working window. After the signal passes through the water layer, sediment layer and overlying medium, it is received by the satellite and combined with the echo or response information to invert the accurate spatial position, buried depth and surrounding environment parameters of the pipeline. The device has the characteristics of high pressure resistance, electromagnetic interference resistance, low power consumption and long endurance, and can work for a long time without manual operation, providing high-precision and sustainable data support for the inspection, positioning and safety evaluation of deep buried pipeline.

[0003] The prior art has the following disadvantages:

[0004] In the prior art, the satellite synchronous detection signal emitting device for underwater deep buried pipeline usually adopts a deep water antenna with a fixed structure, and relies on the structural strength and damping characteristics to resist the disturbance of the regular sea current. However, in complex marine environment, the flow velocity and direction of deep sea current are not stable, but there is a shear force mutation phenomenon in the low frequency interval. When the change amplitude of shear force mutation and the natural frequency of antenna structure form dynamic coupling, the structural resonance of antenna support assembly is easily triggered. In this state, the antenna will produce non-design frequency band side lobe leakage signals outside the normal working frequency band. During the spatial propagation of these signals, they may enter the satellite synchronous receiving window, causing interference in the satellite system when determining the signal arrival time and direction, and then causing large-scale spatial positioning jump. This jump not only causes systematic deviation of the inversion result of the spatial position information of the pipeline, but also causes false judgment of the subsequent inspection, state monitoring and risk warning based on the positioning data, seriously affecting the operation safety and maintenance decision of the deep buried pipeline.

[0005] The above information disclosed in the background section is only used to enhance the understanding of the background of the present disclosure, and therefore it can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] The purpose of the present application is to provide a satellite synchronous detection signal emitting device for underwater deep buried pipeline and an application method thereof to solve the problems in the background.

[0007] To achieve the above object, the application provides the following technical solutions: a satellite synchronous probe signal transmitting device for a large-buried-depth pipeline under water, comprising a low-frequency shear force sensing module, a near-resonance identification modeling module, a target detuning adjustment module, a pre-distortion beam generating module, a leakage spectrum suppression module, and a closed-loop adaptive control module.

[0008] The low-frequency shear force sensing module constructs a low-frequency shear force real-time sensing link, acquires shear gradient and structural strain data under the action of deep-sea currents based on shear force sensors and structural strain sensors arranged on an antenna support assembly, and generates corresponding shear energy spectrum baseline.

[0009] The near-resonance identification modeling module identifies the frequency interval in the near-resonance state according to the shear energy spectrum baseline, measures the inherent frequency drift, couples the inherent frequency drift with the water dynamic parameters related to the shear force, and establishes a parameterized structural model of the antenna support assembly.

[0010] The target detuning adjustment module calculates a target detuning bias value by using the parameterized structural model, and drives the magneto-rheological damper and piezoelectric bypass device connected with the antenna support assembly according to the target detuning bias value.

[0011] The pre-distortion beam generating module updates the feeding phase vector and amplitude weight of the antenna array based on the target detuning bias value, generates a pre-distortion beam for a non-design working frequency band, and suppresses the side beam leakage caused by resonance.

[0012] The leakage spectrum suppression module generates a leakage spectrum mask according to the output of the pre-distortion beam, sets the judgment threshold and transmission time window of the satellite synchronous signal according to the leakage spectrum mask, and shields the signal transmission of the high-risk frequency band.

[0013] The closed-loop adaptive control module acquires the positioning residual and time delay drift parameters of the satellite positioning result, compares and analyzes the parameters with the leakage spectrum and shear energy spectrum baseline, inversely updates the parameterized structural model and target detuning bias value, and uses the updated parameters in the magneto-rheological damper, piezoelectric bypass device and pre-distortion beam control, to form an adaptive closed-loop control process of resisting resonance and suppressing side beam leakage.

[0014] Preferably, the step of constructing the low-frequency shear force real-time sensing link comprises:

[0015] A triaxial shear force sensor with a range of ±5000 Newton and a resolution of 0.05 Newton and a fiber Bragg grating strain sensor with a range of ±3000 micro-strain and a resolution better than 1 micro-strain are arranged at the node position of the antenna support assembly with the highest modal strain energy, and static zero drift test and dynamic sensitivity calibration are completed before installation.

[0016] The sensor signal is transmitted to the time synchronization processing unit through the twisted shield cable, and after low-pass filtering and multi-scale wavelet packet decomposition to extract low-frequency components and high-frequency components, sliding average baseline compensation and fast Fourier transform spectrum analysis are performed, the instantaneous shear gradient and structural strain mode are calculated using synchronous data, and the key influence frequency of low-frequency disturbance is screened through generalized cross-correlation;

[0017] The instantaneous shear gradient and structural strain mode are input to construct the shear energy spectrum baseline, and when the deviation value exceeds the threshold value, it is determined that the sea current shear state deviates significantly from the steady state.

[0018] Preferably, in the process of constructing the shear energy spectrum baseline, the running period is not less than 30 days, each time window length is 600 seconds, adaptive spectral clustering algorithm is used to cluster the energy spectrum curves under different sea current conditions, and the most frequently occurring spectrum shape is extracted from the clustering results as the reference spectrum shape of the target sea area.

[0019] Preferably, the step of identifying the near-resonance state frequency interval according to the shear energy spectrum baseline and establishing a parameterized structural model of the antenna support assembly comprises:

[0020] The shear energy spectrum baseline and the real-time shear energy spectrum are compared point by point in the frequency domain, and when the energy density ratio exceeds the positive threshold value and lasts for two baseline sampling periods and is located within the inherent frequency ± 5% range, it is determined to be in the near-resonance state;

[0021] The inherent frequency drift is measured using the fiber Bragg grating strain sensor and the acceleration response signal in the near-resonance state, and the Hilbert transform is used to align the shear force mutation time, with a measurement accuracy of within 0.01 hertz;

[0022] The inherent frequency drift is coupled with the deep sea current parameters to construct a coupled input set and establish a second-order nonlinear vibration relationship;

[0023] Based on the finite element analysis results and the coupled input set, a parameterized structural model is established, equivalent stiffness, damping and mass correction variables are introduced, and Kalman filtering is used to real-time correct the model parameters to maintain adaptive ability.

[0024] Preferably, the hydrodynamic drag coefficient and lift coefficient in the hydrodynamic parameters are obtained by numerical fluid dynamics simulation combined with physical water tank test calibration, and the parameterized structural model receives real-time shear force data, strain data and inherent frequency drift every interval not exceeding 60 seconds during operation, and updates the model parameters in real time.

[0025] Preferably, the step of calculating the target detuning bias value using the parameterized structural model and driving the magnetorheological damper and piezoelectric bypass device to realize synchronous adjustment of equivalent stiffness and damping comprises:

[0026] The current parameterized structure model is input into the shear force data, the structural strain data, the inherent frequency drift amount and the hydrodynamic parameters, the dynamic response is predicted and the difference value with the static inherent frequency is calculated as an initial estimated value of the target detuning bias value;

[0027] The initial estimated value is combined with the real-time modal analysis result for dynamic correction, so as to ensure that the difference between the predicted frequency and the actual frequency is not more than 0.02 Hz, the target detuning bias value after correction is used to drive the magneto-rheological damper to adjust the damping force, and the piezoelectric bypass device to adjust the equivalent stiffness, and the proportion is adjusted according to the disturbance amplitude distribution;

[0028] The dynamic response is monitored and fed back to the model, the effect is verified, and the optimized value is stored or secondary adjustment is carried out until the preset performance index is reached.

[0029] Preferably, the step of updating the antenna array feed phase vector and amplitude weight based on the target detuning bias value to generate a pre-distortion beam comprises:

[0030] The target detuning bias value after correction is combined with the array geometric layout, the element spacing, the working frequency and the attitude, and the initial state of the array directivity diagram is determined by using the amplitude and phase response database;

[0031] The target detuning bias value is mapped to a resonance risk frequency interval side lobe suppression target, the phase offset and amplitude change of each element are calculated, and the feed phase vector and amplitude weight after correction are generated;

[0032] The amplitude and phase of each radiation element are adjusted synchronously through the phase shift controller and the variable attenuator, and real-time amplitude and phase verification and secondary fine tuning are carried out after adjustment, the array radiation distribution is collected in the underwater test field to verify the side lobe suppression effect, and when qualified, it is stored as a standard configuration, and when not up to standard, the parameters are optimized and verified repeatedly.

[0033] Preferably, the step of generating a leakage spectrum mask according to the pre-distortion beam output and setting a satellite synchronization signal judgment threshold and a transmission time window comprises:

[0034] The radiation signal spectrum data of the pre-distortion beam at different azimuth and elevation angles in the whole space is collected, and is time-synchronized with the array working state;

[0035] The measured beam spectrum shape is compared with the designed spectrum shape, the non-design frequency point with excessive amplitude is identified, and an adaptive attenuation mask curve is generated to form a leakage spectrum mask;

[0036] Based on the leakage spectrum mask, the amplitude threshold and the phase offset tolerance are set, and the transmission time window with a second-level precision is determined in combination with the satellite visibility prediction and the sea current disturbance prediction;

[0037] The determination threshold and transmission time window are applied to the running and dynamically monitored adjustment, and the amplitude and phase fine tuning or delayed transmission is performed when the leakage approaches the threshold, and the running data is stored to form a leakage control strategy library.

[0038] Preferably, the step of collecting the positioning residual of the satellite positioning result and the time delay drift parameter and inversely updating the parameterized structure model and the target mismatch bias value comprises:

[0039] Obtain the positioning residual and time delay drift real-time data and record them synchronously with the environmental parameters at the transmission time;

[0040] Compare the data with the leakage spectrum and shear spectrum baseline point by point and perform multi-source correlation analysis to determine the resonance risk;

[0041] Input the analysis result into the parameterized structure model to correct the hydrodynamic parameters and structure parameters, and calculate a new target mismatch bias value through iterative optimization;

[0042] Apply the new target mismatch bias value to the magneto-rheological damper, piezoelectric bypass device and antenna array amplitude and phase control to realize adaptive closed-loop anti-resonance and side lobe leakage suppression.

[0043] The satellite synchronous signal transmission method for underwater large-buried pipeline comprises the following steps:

[0044] A low-frequency shear force real-time sensing link is constructed, based on the shear force sensor and structure strain sensor arranged on the antenna support assembly, shear gradient and structure strain data under the action of deep sea current are collected, and corresponding shear spectrum baseline is generated;

[0045] According to the shear spectrum baseline, the frequency interval in the near-resonance state is identified, and the inherent frequency drift is measured, the inherent frequency drift and the hydrodynamic parameter related to the shear force are coupled, and the parameterized structure model of the antenna support assembly is established;

[0046] The target mismatch bias value is calculated by using the parameterized structure model, and the magneto-rheological damper and piezoelectric bypass device connected with the antenna support assembly are driven according to the target mismatch bias value;

[0047] The feeding phase vector and amplitude weight of the antenna array are updated based on the target mismatch bias value, a pre-distortion beam for the non-design working frequency band is generated, and the side lobe leakage caused by resonance is suppressed;

[0048] The leakage spectrum mask is generated according to the output of the pre-distortion beam, and the determination threshold and transmission time window of the satellite synchronous signal are set according to the leakage spectrum mask, and the signal transmission of the high-risk frequency band is shielded;

[0049] The positioning residual of the satellite positioning result and the time delay drift parameter are collected, the parameter is compared and analyzed with the leakage spectrum and the shearing energy spectrum baseline, the parameterized structure model and the target mistuning bias value are inversed and updated, and the updated parameter is used in the magnetorheological damper, the piezoelectric bypass device and the pre-distortion beam control, to form an adaptive closed loop control process for resisting resonance and inhibiting the leakage of the sub-beam.

[0050] In the above technical solution, the technical effects and advantages provided by the application are as follows:

[0051] The application realizes real-time prediction and active inhibition of the resonance risk of the antenna support assembly under the complex environment of deep sea, by constructing a low-frequency shear force real-time sensing link, calculating the target mistuning bias value by the parameterized structure model, and performing collaborative dynamic adjustment of damping and stiffness, and combining the antenna array pre-distortion beam control based on the target mistuning bias value and the leakage spectrum mask screening. Not only can the resonance be predicted before the low-frequency shear force mutation occurs, but also the structure dynamics and electromagnetic radiation characteristics can be quickly adjusted when the resonance risk occurs, so that the sub-beam leakage of the non-design working frequency band is significantly inhibited, thereby effectively reducing the interference probability in the satellite synchronous receiving window and ensuring the stability and accuracy of the pipeline spatial positioning result.

[0052] The application realizes multi-dimensional integrated collaborative optimization from the structure layer, signal layer to link layer, by multi-source fusion analysis of the satellite positioning residual, time delay drift and other external link performance feedback, leakage spectrum and shearing energy spectrum baseline, forming a closed loop adaptive updating mechanism of the parameterized structure model, and directly driving the magnetorheological damper, piezoelectric bypass device and antenna array amplitude and phase control. The closed loop control mode enables the system to automatically adapt to different current conditions and structural state changes in long-time deep sea operation, continuously maintain the best state of anti-resonance and inhibition of sub-beam leakage, greatly prolong the unattended operation cycle of the equipment, and significantly improve the reliability and long-term data effectiveness of the satellite synchronous detection of the deep buried pipeline. BRIEF DESCRIPTION OF DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0054] Figure 1 It is a module schematic diagram of the satellite synchronous detection signal transmitting device of the underwater large buried depth pipeline of the present application.

[0055] Figure 2 It is a method flowchart of the satellite synchronous detection signal transmitting method of the underwater large buried depth pipeline of the present application. DETAILED DESCRIPTION

[0056] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the examples set forth herein; rather, these example implementations are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example implementations to those skilled in the art.

[0057] The present application provides a satellite synchronous detection signal transmitting device for underwater large buried pipeline as shown in Figure 1 The satellite synchronous detection signal transmitting device for underwater large buried pipeline comprises a low-frequency shear force sensing module, a near-resonance identification modeling module, a target detuning adjustment module, a pre-distortion beam generation module, a leakage spectrum suppression module, and a closed-loop adaptive control module.

[0058] The low-frequency shear force sensing module constructs a low-frequency shear force real-time sensing link, based on shear force sensors and structural strain sensors arranged on the antenna support assembly, collects shear gradient and structural strain data under the action of deep sea currents, and generates corresponding shear energy spectrum baseline.

[0059] The process of constructing a low-frequency shear force real-time sensing link includes the following steps:

[0060] High-precision triaxial shear force sensors and fiber Bragg grating strain sensors are arranged at key stress positions of the antenna support assembly. The triaxial shear force sensor has a range of ±5000 Newton and a resolution of 0.05 Newton, and can accurately capture shear load components in different directions within the range of 0.01 Hz to 50 Hz; the fiber Bragg grating strain sensor has a range of ±3000 micro-strain and a resolution better than 1 micro-strain, and can work stably within the temperature range of -5 degrees Celsius to 50 degrees Celsius. Each triaxial shear force sensor is packaged with a titanium alloy shell, with a protection level of IP69K, and a fluorinated polymer coating is applied to the outer wall of the package to prevent seawater corrosion; the fiber part of each fiber Bragg grating strain sensor is made of quartz material, coated with a polymer coating, and filled with pressure-resistant epoxy resin. The sensors are installed on the node positions of the antenna support assembly with the highest modal strain energy. These positions are determined as stress concentration areas of the first bending mode and the first torsional mode through finite element modal analysis, ensuring that the maximum amplitude of stress and strain response signals can be obtained under the action of low-frequency shear force. Before installation, all sensors are tested for static zero drift and dynamically calibrated in a laboratory tank. The calibration uses a force loading platform driven by a precision stepper motor to apply a known load that increases step by step, and records the difference between the output signal and the theoretical value, ensuring that the error does not exceed 0.5% of the rated range.

[0061] Secondly, the signal of the above-mentioned sensor is transmitted to the time synchronization processing unit through a twisted shielded cable, and the outer layer of the cable is coated with a polyurethane sheath to prevent mechanical wear and tear. The time synchronization processing unit is internally integrated with a constant temperature crystal oscillator with a frequency stability better than ±0.1ppm, and is equipped with a time chip synchronized with the global satellite navigation system signal to realize nanosecond-level signal time stamping. Each sensor signal is first passed through a hardware low-pass filter (with a cutoff frequency of 60Hz) to remove high-frequency noise, and then the low-frequency component in the range of 0.01Hz to 5Hz and the high-frequency component in the range of 5Hz to 50Hz are separated by a multi-scale wavelet packet decomposition algorithm. The low-frequency component is used to detect shear force mutations, and the high-frequency component is used to judge the structure micro-vibration characteristics. Subsequently, the signal is compensated for baseline drift using a sliding average window (window length of 200 seconds), and the frequency spectrum amplitude distribution of each time window is calculated in the frequency domain by fast Fourier transform, and the shear force signal and the strain signal are mapped to the same absolute time axis and spatial coordinate system.

[0062] After obtaining the time-synchronized data, the instantaneous shear gradient and the structure strain pattern are calculated. Specifically, the instantaneous load data of the three-axis shear force sensor arranged at different spatial positions is calculated according to the spatial position difference formula Δτ / Δx to obtain the gradient distribution of the shear force between adjacent measuring points, and a three-dimensional shear gradient field is drawn. The strain curve of the fiber Bragg grating strain sensor in the same time window is input into the principal component analysis (PCA) algorithm, and the first two principal components are extracted as the main feature vectors of the structure strain pattern. After obtaining the shear gradient field and the strain pattern, the generalized cross-correlation (GCC) is used to calculate the correlation coefficient distribution between them, and the characteristic frequency with a correlation coefficient greater than 0.8 is selected as the key influencing frequency of low-frequency disturbance. This calculation result can accurately identify which frequency components form a strong coupling between the hydrodynamic load and the structure response, providing direct input for subsequent resonance risk prediction.

[0063] Finally, the obtained instantaneous shear gradient and structure strain pattern are used as input variables to construct a shear energy spectrum baseline. The construction method is as follows: in a running period of not less than 30 days, the shear gradient amplitude square sum of each time window (window length of 600 seconds) is calculated to obtain the energy value, and the strain pattern characteristic amplitude square sum is added to obtain the total energy density; the total energy density of all time windows is weighted and averaged according to the frequency interval to obtain the global average energy spectrum curve under steady-state conditions. Subsequently, the adaptive spectral clustering algorithm is used to cluster the energy spectrum curves under different current conditions to obtain the background spectrum cluster, and the most frequently occurring spectrum shape is extracted as the reference spectrum shape of the target sea area. This reference spectrum shape is the shear energy spectrum baseline, which can be compared with the real-time energy spectrum point by point during operation to calculate the deviation value. When the deviation value exceeds the set threshold (such as 5%), it can be judged that the current current shear state has deviated significantly from the steady state, providing a scientific basis for near-resonance state identification and subsequent active suppression measures.

[0064] Through the above-mentioned specific steps, continuous, high-precision and real-time sensing of low-frequency shear force can be realized, and the sensed data is highly consistent with the actual stress state of the antenna support assembly, thereby laying a reliable data foundation for establishing an accurate hydrodynamic-structure coupling model.

[0065] The near-resonance identification modeling module identifies the frequency range in the near-resonance state according to the shear energy spectrum baseline, measures the inherent frequency drift, couples the inherent frequency drift with the water dynamic parameter related to the shear force, and establishes a parameterized structure model of the antenna support assembly.

[0066] The process of identifying the frequency range in the near-resonance state according to the shear energy spectrum baseline and establishing a parameterized structure model of the antenna support assembly includes the following steps:

[0067] The shear energy spectrum baseline obtained in the previous stage is compared with the shear energy spectrum collected in real time in the frequency domain point by point. The comparison method is as follows: the real-time energy spectrum is divided into multiple frequency point intervals at a frequency interval of 0.01 Hz, the difference between the energy density and the baseline energy density is calculated in each frequency point interval, and the ratio of the difference to the baseline value is calculated. When the energy density ratio of a certain frequency interval exceeds the positive threshold (for example, +10%) and the duration exceeds two baseline sampling periods, the frequency interval is marked as a possible near-resonance risk zone. In order to ensure the accuracy of identification, the frequency components of this risk zone also need to be cross-verified with the results of structural modal analysis. Only when the frequency components are within ±5% of the inherent frequency of the antenna support assembly, it is determined that the interval is in the near-resonance state.

[0068] After confirming the frequency range in the near-resonance state, the inherent frequency drift of the antenna support assembly is measured. The specific method is to use the signals of the fiber Bragg grating strain sensors arranged at multiple high-strain sensitive positions of the support assembly to perform modal response analysis: first, the frequency spectrum peak position of each time slice is calculated by short-time Fourier transform, and then the change curve of these peak values over time is compared with the inherent frequency under the baseline static water condition, and the difference is the inherent frequency drift. In order to eliminate the influence of sea current background noise, the Hilbert transform envelope line of the acceleration response signal is introduced in the analysis to calculate the instantaneous frequency, and the instantaneous frequency curve is aligned with the shear force mutation time, so as to ensure the clear causal relationship between the drift and external disturbance. The measurement accuracy of the drift is controlled within 0.01 Hz to ensure the calculation accuracy of the subsequent structure model parameterization.

[0069] The inherent frequency shift is coupled with the hydrodynamic parameters related to the shear force to form a coupled input set that can describe the dynamic characteristics of the antenna support assembly. The hydrodynamic parameters include the deep sea current velocity, direction, density, viscosity coefficient, and the hydrodynamic drag coefficient and lift coefficient related to the shape of the support assembly. The sea current velocity and direction are directly measured by the Doppler current profiler at the depth of the sensor array, the seawater density and viscosity coefficient are calculated from the temperature and salinity sensor data, and the hydrodynamic drag coefficient and lift coefficient are calibrated by numerical fluid dynamics simulation combined with experimental tank test. In the coupling process, the inherent frequency shift is taken as a dynamic variable, and the hydrodynamic parameters are taken as external excitation parameters. A mathematical relationship between the structural dynamic response and external disturbance is established by a second-order nonlinear vibration equation. The parameters of the equation are determined by least squares fitting of the historical data set, thereby obtaining an accurate mathematical model that can reflect the structural response law under specific sea conditions and specific current conditions.

[0070] After completing the construction of the coupled input set, a parameterized structural model of the antenna support assembly is established. The model takes the finite element structural analysis results as the geometric and mechanical basis, and maps the physical parameters such as geometric size, material elastic modulus, damping ratio, connection stiffness, etc. with the inherent frequency shift and hydrodynamic parameters. By introducing parameterized control variables such as equivalent stiffness adjustment coefficient, equivalent damping adjustment coefficient and mass distribution correction coefficient, the structural response characteristics under different damping and stiffness states can be simulated in the model. In order to ensure the adaptive ability of the model, the real-time measured shear force data, strain data and inherent frequency shift are continuously input into the model during operation, and the parameters are corrected in real time by Kalman filtering algorithm, so that the model can be continuously updated with environmental changes. The parameterized structural model not only can predict the dynamic response of the antenna support assembly under different current conditions in the future, but also can provide high-precision theoretical basis for subsequent target detuning bias calculation and active anti-resonance control, thereby ensuring the stable emission and high-precision positioning of satellite synchronous detection signals in complex marine environment.

[0071] The target detuning adjustment module calculates the target detuning bias value using the parameterized structural model, and drives the magneto-rheological damper and piezoelectric bypass device connected to the antenna support assembly according to the target detuning bias value, to realize the synchronous adjustment of the equivalent stiffness and damping of the support assembly.

[0072] The process of calculating the target detuning bias value using the parameterized structural model and driving the magneto-rheological damper and piezoelectric bypass device to realize the synchronous adjustment of the equivalent stiffness and damping includes the following steps:

[0073] The current version of the parametric structural model of the antenna support assembly established in the previous stage is taken as the basis for calculation, and near real-time collected shear force data, structural strain data, inherent frequency drift, and hydrodynamic parameters such as sea current velocity, sea current direction, seawater density, and seawater viscosity coefficient are input. The model is used to predict the dynamic response curve of the antenna support assembly under the current environmental conditions. The prediction results include the maximum strain response value of the structure, the maximum displacement amplitude, and the main frequency component. The predicted main frequency is compared with the static inherent frequency of the support assembly, and the difference between the current structural response frequency and the inherent frequency is calculated, which is the initial estimate of the target detuning bias value. The core of this step is that the parametric structural model not only considers the static structural characteristics, but also introduces the coupling relationship between the hydrodynamic load and the structural geometry and material properties, so it can give high-precision response frequency prediction results under different environmental disturbances, thus making the target detuning bias value targeted.

[0074] After obtaining the initial estimate, it is input into the dynamic correction link to eliminate the deviation between the model prediction and the actual measurement. Specifically, by performing modal analysis on the real-time fiber Bragg grating strain sensors and acceleration sensors arranged on the antenna support assembly, the actual vibration frequency and mode shape distribution of the structure under the current sea current conditions are directly measured and compared with the model prediction results. If the difference exceeds the set threshold, for example, the difference between the actual frequency and the predicted frequency exceeds 0.02 Hz, the target detuning bias value is corrected according to the direction and amplitude of the difference, so that it is closer to the target frequency that can effectively avoid the resonance interval. This correction process is completed within a time scale of seconds to ensure the effectiveness of the detuning strategy when the sea current disturbance changes rapidly. The target detuning bias value corrected through this step is the final control quantity used for adjustment. According to the final target detuning bias value, the magneto-rheological damper and the piezoelectric bypass device installed on the antenna support assembly are driven to adjust the equivalent stiffness and damping characteristics simultaneously. The working principle of the magneto-rheological damper is to control the yield stress of the magneto-rheological fluid by changing the size of the coil current, thereby changing the damping force. According to the adjustment amplitude of the required damping force calculated based on the target detuning bias value, the corresponding current command is accurately applied to the damper coil to change the damping performance within milliseconds. The role of the piezoelectric bypass device is to change the equivalent elastic modulus of the piezoelectric ceramic element by controlling the bias voltage applied to it, thereby realizing the continuous adjustment of the equivalent stiffness of the support assembly. The controller allocates the damping adjustment proportion and the stiffness adjustment proportion according to the target detuning bias value, for example, preferentially increasing the damping under high-amplitude disturbance conditions, and preferentially increasing the stiffness under low-amplitude but long-duration disturbance conditions, to avoid the resonance interval with the smallest structural response amplitude.

[0075] After completing the damping and stiffness synchronous adjustment, the dynamic response of the support assembly is continuously monitored, and the response data is fed back to the parameterized structure model in real time for closed-loop correction to verify whether the target detuning bias value achieves the expected effect. When it is detected that the structural response frequency has successfully moved out of the near resonance interval and the side lobe leakage signal amplitude has significantly decreased, the current damping and stiffness settings are maintained, and the settings are stored in the historical database together with the corresponding environmental parameters and structural response data as reference optimization values for subsequent similar sea current conditions; when it is detected that the response frequency is still close to the resonance interval or the side lobe leakage signal has not significantly decreased, the secondary adjustment of the target detuning bias value is started, and the above steps are repeated until the preset performance indicators are reached. Through this continuous feedback and adaptive adjustment strategy, the antenna support assembly can maintain stable dynamic performance in different sea current disturbance environments during long-term deep sea operation, thereby providing reliable protection for stable transmission of satellite synchronization detection signals and minimizing the risk of side lobe leakage caused by resonance.

[0076] A pre-distortion beam generation module updates the feed phase vector and amplitude weight of the antenna array based on the target detuning bias value, generates a pre-distortion beam for a non-design working frequency band, and suppresses the side lobe leakage caused by resonance.

[0077] The process of updating the feed phase vector and amplitude weight of the antenna array based on the target detuning bias value to generate a pre-distortion beam for a non-design working frequency band includes the following steps:

[0078] After obtaining the target detuning bias value calculated and corrected in the previous stage, the value is taken as an input parameter, and the initial state of the array pattern in the current environment is determined in combination with the geometric layout, element spacing, working frequency range and installation attitude of the antenna array. To this end, first, the amplitude and phase response of each radiating element of the antenna array is calibrated, and the calibration is carried out in still water conditions and actual deep sea working conditions respectively to ensure that the true amplitude and phase response curve under environmental interference can be obtained. During the calibration process, the elements are excited one by one through phased driving, and the receiving power distribution at different azimuth and elevation angles in the whole space is recorded, thereby establishing an amplitude and phase response database of the radiating elements. This database will serve as a reference basis for subsequent phase vector and amplitude weight adjustment.

[0079] The target mismatch bias value is mapped to the modified target of the array directional pattern. The mapping relationship is established based on a large number of simulation and measurement data in advance. The specific process is as follows: the resonance risk frequency interval corresponding to the mismatch bias value is taken as the directional pattern sidelobe frequency band that needs to be weakened, and the phase offset and amplitude proportional change of each unit radiation signal relative to the array reference point in the frequency band range are calculated. By matching these changes with the existing amplitude and phase response database, a set of modified feed phase vector and amplitude weight target values are generated. The setting principle of these target values is to make the sidelobe directional gain in the resonance risk frequency interval decrease by at least 6 decibels on the premise of not significantly decreasing the main lobe gain, so as to maximize the suppression of the radiation energy in the non-design working frequency band.

[0080] According to the modified feed phase vector and amplitude weight target values, synchronous adjustment is performed on each radiation unit of the antenna array. The adjustment process is completed by a high-precision phase shift controller and a variable attenuator. The phase shift controller is responsible for adjusting the phase of the input signal of each unit to the target value, and the resolution can reach 0.1 degree. The variable attenuator is used to adjust the amplitude of the input signal of each unit to the target weight, and the adjustment accuracy is better than 0.05 decibels. In order to prevent the influence of temperature drift on amplitude and phase stability in deep sea high pressure environment, amplitude and phase verification is carried out immediately after each adjustment is completed. The output signals of each unit are collected in real time through the monitoring channel inside the array, and are compared with the target values point by point. If the error exceeds the set threshold, secondary fine tuning is immediately performed until the accuracy requirement is met. The synchronous adjustment strategy ensures the amplitude and phase consistency in the entire array scale, thereby ensuring the formation accuracy of the pre-distortion beam.

[0081] After the amplitude and phase adjustment is completed, the performance of the pre-distortion beam is verified through the array omnidirectional radiation test. The specific method is as follows: in the underwater test field, the spatial distribution data of the array radiation is collected in real time through the measurement antennas arranged at different azimuths and depths, and the data is compared and analyzed with the original directional pattern to confirm whether the sidelobe suppression effect in the resonance risk frequency interval reaches the preset target. When the test results show that the sidelobe in the risk band is effectively suppressed and the main lobe gain remains within the allowed range, the current feed phase vector and amplitude weight are stored as the standard configuration file under the environmental conditions, and are recorded in the long-term operation database together with the corresponding target mismatch bias value; if the test results do not meet the expectation, the reason why the sidelobe is not completely suppressed is analyzed according to the test data, and the pre-distortion effect can be further improved by fine tuning the amplitude and phase parameters of individual units or optimizing the amplitude and phase difference between adjacent units, and then verified again until the requirement is met. Through the above process, a high-precision pre-distortion beam for the non-design working frequency band can be generated in real time according to the target mismatch bias value under different sea current disturbances and structure states, so as to effectively suppress the sidelobe leakage caused by structure resonance and ensure that the satellite synchronous detection signal is stably and accurately radiated in the design frequency band.

[0082] A leakage spectrum suppression module generates a leakage spectrum mask according to the output of the predistortion beam, and sets a decision threshold and a transmission time window of the satellite synchronization signal according to the leakage spectrum mask, so as to shield signal transmission in a high-risk frequency band.

[0083] The process of generating a leakage spectrum mask according to the output of the predistortion beam and setting a decision threshold and a transmission time window of the satellite synchronization signal according to the leakage spectrum mask includes the following steps:

[0084] After completing the predistortion beam amplitude and phase adjustment for the non-design working frequency band, the radiation signal spectrum data of the antenna array at different azimuth and elevation angles in the full space is collected. During the collection process, multiple groups of high-sensitivity wideband receiving antennas arranged at different azimuths are used, and the output power distribution of the predistortion beam in the working frequency band and the non-design working frequency band is recorded simultaneously. Each receiving antenna is connected to a high-resolution spectrum analysis device, the bandwidth of the analysis device covers the entire possible radiation frequency band, and the resolution is better than 0.01 Hz, so as to ensure that the subtle leakage components caused by structural resonance or amplitude and phase micro-deviation can be captured. During the collection process, by aligning with the time synchronization signal of the array transmission control end, each spectrum sample is corresponded to the array working state one by one, to form an accurate time-frequency domain output characteristic data set.

[0085] The collected predistortion beam output characteristic data is subjected to leakage spectrum identification and mask generation. The specific method is as follows: first, the theoretical beam spectrum in the design working frequency band is compared with the measured beam spectrum in the frequency domain, and the non-design frequency points exceeding the design spectrum amplitude threshold are identified as potential leakage frequency points; then, taking these potential leakage frequency points as the center, the leakage bandwidth range is determined according to the frequency correlation analysis result, and an attenuation mask curve is generated in the bandwidth range, and the attenuation depth of the curve is dynamically adjusted according to the size of the leakage amplitude, for example, the frequency components with high leakage amplitude correspond to deeper attenuation amplitude. The mask curve is superimposed with the design working spectrum in the full frequency range to form a complete leakage spectrum mask diagram, which is directly used as the basis for setting the decision threshold. The creativity of this process lies in that the mask curve is not a static template, but is adaptively generated combined with real-time measurement data and environmental conditions, so that targeted leakage suppression can be achieved under different sea current disturbances and antenna support states.

[0086] The generated leakage spectrum mask is used to set the determination threshold and transmission time window of the satellite synchronization signal. The determination threshold includes amplitude threshold and phase offset tolerance. The amplitude threshold is set according to the lowest attenuation point of the mask curve in the leakage frequency band, so that the power level of the transmitted signal in the frequency band is lower than the minimum effective receiving sensitivity of the satellite synchronization receiver. The phase offset tolerance is used to prevent the energy leakage caused by frequency modulation sideband or phase noise from crossing the receiving window. The transmission time window is set in combination with the satellite visibility prediction and the sea current disturbance prediction results. The transmission time of the antenna array is arranged in the period with the lowest sidelobe leakage risk, for example, in the period with the lowest tidal current speed or in the period with the lowest structural response amplitude. The start and end times of the time window are accurate to seconds, so that the leakage risk is always within the controllable range during the entire transmission period.

[0087] Finally, the set determination threshold and transmission time window strategy are applied to the actual operation process, and a dynamic monitoring and adjustment mechanism is established. In each transmission period, the matching degree of the array output signal and the leakage spectrum mask is monitored in real time. Once it is detected that the leakage frequency component approaches or exceeds the threshold set by the mask curve, the amplitude and phase fine tuning program or the delay transmission operation is triggered immediately, so as to suppress the leakage in real time without affecting the quality of the main task signal. In addition, the leakage spectrum data, threshold setting value, transmission time window arrangement and corresponding environmental parameters of each operation are stored in the operation history database, and a leakage control strategy library for different sea areas and different environmental conditions is formed through long-term accumulation. The strategy library can be directly called in future operation to realize rapid deployment and adaptive optimization, so as to ensure that the satellite synchronization signal transmission process is always within the safe and controllable frequency spectrum radiation range in the complex deep sea environment, and effectively reduce the satellite positioning jump risk caused by sidelobe leakage.

[0088] The closed-loop adaptive control module collects the positioning residual and time delay drift parameters of the satellite positioning result, compares and analyzes the parameters with the leakage spectrum and shear energy spectrum baseline, inversely updates the parameterized structure model and target detuning bias value, and applies the updated parameters to the magneto-rheological damper, piezoelectric bypass device and pre-distortion beam control to form an adaptive closed-loop control process for resisting resonance and suppressing sidelobe leakage.

[0089] The positioning residual and time delay drift parameters of the satellite positioning result are collected, compared and analyzed with the leakage spectrum and shear energy spectrum baseline, and then the parameterized structure model and target detuning bias value are inversely updated, and the updated parameters are applied to the magneto-rheological damper, piezoelectric bypass device and pre-distortion beam control, which specifically includes the following steps:

[0090] Real-time data of positioning residual and time delay drift are obtained at the receiving end of the satellite synchronous probe signal. The method for obtaining the positioning residual is to perform difference between the pipeline space position coordinates measured by the satellite receiver and the reference position coordinates to obtain the instantaneous position deviation in the three-dimensional coordinate system. The method for obtaining the time delay drift is to compare the time stamp at the transmitting end with the signal arrival time recorded by the satellite receiver to obtain the deviation of the signal propagation delay from the theoretical value. In order to ensure the high accuracy and traceability of the data, all time comparisons use a time unit synchronized with the global satellite navigation system signal, and the time resolution is better than nanoseconds. The positioning residual and time delay drift data are collected at a fixed sampling period (such as once per second), and at the same time, environmental parameter information of the transmission time is attached, including sea current velocity, sea current direction, water temperature, salinity, etc., which are used for subsequent correlation analysis.

[0091] The collected positioning residual and time delay drift parameters are comprehensively compared and analyzed with the leakage spectrum and shear energy spectrum baseline. Specifically, first, the leakage spectrum data generated in the current transmission period are aligned with the historical baseline leakage spectrum to identify the leakage frequency position, leakage bandwidth range and leakage amplitude change trend; then, the shear energy spectrum calculated in real time under the current sea current condition is compared with the baseline energy spectrum point by point, the energy deviation percentage of the low frequency band is calculated, and cross correlation analysis is performed with the leakage spectrum change. If the shear energy spectrum low frequency band appears obvious energy rise at the same time of the leakage spectrum change, it can be judged that there is a direct correlation between the leakage signal and the sea current disturbance. Further, these change trends are matched with the fluctuation mode of the positioning residual and the time delay drift, if the positioning residual increases and the time delay drift intensifies at the same time of the leakage spectrum enhancement, it can be inferred that the current antenna support assembly may enter the resonance or near resonance state. The creativity of this comprehensive analysis method lies in that it does not rely on the change of a single signal source, but through the fusion of satellite positioning accuracy, time delay stability, radiation spectrum distribution and sea current energy spectrum multi-source data, a high credibility judgment of resonance risk is formed.

[0092] Based on the comprehensive analysis results, the parameterized structural model and the target detuning bias value are updated. The inversion process includes: first, the amplitude change trend of the leakage spectrum and the energy deviation of the low frequency band of the shear spectrum are input into the disturbance input channel of the parameterized structural model, which is used to modify the hydrodynamic action parameters; at the same time, the positioning residual and the change curve of time delay drift are input into the structural response channel of the model, which is used to modify the equivalent stiffness, equivalent damping and mass distribution parameters in the model. In the modification process, the iterative optimization method based on the least error fitting is adopted, and through multiple rounds of parameter adjustment, the difference between the model predicted positioning residual and time delay drift value and the measured value is minimized. After the model is updated, the new target detuning bias value is calculated according to the new model, which can maximize the shift of the structural response frequency out of the resonance interval under the current environmental conditions, and ensure that the sub-beam leakage level is reduced to below the sensitivity threshold of the satellite synchronous receiver. The uniqueness of this inversion update step is that the update not only depends on the response data of the structure itself, but also introduces external feedback of satellite positioning and time delay drift, so that the model adjustment process can take into account the electromagnetic radiation characteristics of the transmission link and the spatial positioning accuracy requirements.

[0093] Finally, the updated target detuning bias value is applied to the magneto-rheological damper, piezoelectric bypass device and pre-distortion beam control to realize adaptive closed-loop control of anti-resonance suppression of sub-beam leakage. In the execution process, the control unit generates damping adjustment instructions and stiffness adjustment instructions according to the new target detuning bias value, which are applied to the magneto-rheological damper and piezoelectric bypass device respectively, to quickly change the dynamics of the support assembly at the physical level; at the same time, the bias value is used to update the feed phase vector and amplitude weight of each radiation element of the antenna array to continuously form a pre-distortion beam for non-design frequency band at the signal level. After execution, the next round of positioning residual and time delay drift collection and analysis is immediately entered, thus forming a closed-loop feedback. The adaptability of the closed-loop control lies in that when the environmental disturbance pattern changes, for example, the sea current velocity suddenly rises or the direction reverses, the model will be updated according to the new residual and drift information in the next sampling period, ensuring that the control strategy always matches the current actual working environment. Through long-term operation, this closed-loop control process can form a set of anti-resonance and leakage suppression strategies that dynamically evolve with environmental conditions, greatly improving the long-term stability and positioning accuracy of the satellite synchronous detection signal.

[0094] The application realizes real-time prediction and active inhibition of resonance risk of an antenna support assembly under a deep-sea complex environment by constructing a low-frequency shear force real-time perception link, calculating a target mistuning bias value of a parameterized structure model, performing collaborative dynamic adjustment of damping and stiffness, and combining antenna array pre-distortion beam control and leakage spectrum mask screening based on the target mistuning bias value.

[0095] The application forms a closed-loop adaptive updating mechanism of the parameterized structure model by multi-source fusion analysis of satellite positioning residual error, time delay drift and other external link performance feedback, leakage spectrum and shear energy spectrum baseline, and directly drives the magneto-rheological damper, piezoelectric bypass device and antenna array amplitude and phase control to realize multi-dimensional integrated collaborative optimization from the structure layer, signal layer to link layer. The closed-loop control mode enables the system to automatically adapt to different current conditions and structural state changes in long-time deep-sea operation, continuously maintain the best state of anti-resonance and suppression of side beam leakage, greatly prolong the unattended operation cycle of the equipment, and significantly improve the reliability and long-term data effectiveness of deep buried pipeline satellite synchronous detection.

[0096] The application provides a satellite synchronous detection signal transmission method for a large-buried-depth underwater pipeline as shown in Figure 2 The application provides a satellite synchronous detection signal transmission method for a large-buried-depth underwater pipeline as shown in

[0097] A low-frequency shear force real-time perception link is constructed, shear gradient and structural strain data under the action of deep-sea current are collected based on shear force sensors and structural strain sensors arranged on the antenna support assembly, and corresponding shear energy spectrum baseline is generated;

[0098] The frequency interval in the near-resonance state is identified according to the shear energy spectrum baseline, and the inherent frequency drift is measured, the inherent frequency drift and the hydrodynamic parameter related to the shear force are coupled, and the parameterized structure model of the antenna support assembly is established;

[0099] The target mistuning bias value is calculated by using the parameterized structure model, and the magneto-rheological damper and piezoelectric bypass device connected with the antenna support assembly are driven according to the target mistuning bias value;

[0100] The target mistuning bias value is calculated by using the parameterized structure model, and the magneto-rheological damper and piezoelectric bypass device connected with the antenna support assembly are driven according to the target mistuning bias value;

[0101] The leakage spectrum mask is generated according to the output of the pre-distortion beam, and the determination threshold and transmission time window of the satellite synchronization signal are set according to the leakage spectrum mask, so that the signal transmission of the high-risk frequency band is shielded.

[0102] The positioning residual of the satellite positioning result and the time delay drift parameter are collected, the parameters are compared and analyzed with the leakage spectrum and the shearing energy spectrum baseline, the parameterized structure model and the target detuning bias value are inversed and updated, the updated parameters are used in the magneto-rheological damper, the piezoelectric bypass device and the pre-distortion beam control, and the adaptive closed-loop control process of anti-resonance suppression of the sub-beam leakage is formed.

[0103] The satellite synchronous detection signal emission method for the underwater large-buried pipeline provided by the embodiment of the application is implemented by the satellite synchronous detection signal emission device for the underwater large-buried pipeline, and the specific method and process of the satellite synchronous detection signal emission device for the underwater large-buried pipeline are described in the embodiment of the satellite synchronous detection signal emission method for the underwater large-buried pipeline, which will not be described here.

[0104] The above only describes some exemplary embodiments of the application by way of illustration, and it is needless to say that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the application. Therefore, the above drawings and descriptions are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the application.

Claims

1. A satellite synchronous signal transmission device for underwater large buried depth pipeline, characterized in that, The low-frequency shear force perception module, the near-resonance identification modeling module, the target mistuning adjustment module, the pre-distortion beam generation module, the leakage spectrum suppression module, and the closed-loop adaptive control module are included. The low-frequency shear force perception module constructs a low-frequency shear force real-time perception link, acquires shear gradient and structural strain data under the action of deep-sea current based on shear force sensors and structural strain sensors arranged on the antenna support assembly, and generates a corresponding shear energy spectrum baseline. The near-resonance identification modeling module identifies the frequency interval in the near-resonance state according to the shear energy spectrum baseline, measures the inherent frequency drift, couples the inherent frequency drift with the water dynamic parameters related to the shear force, and establishes a parameterized structural model of the antenna support assembly. The target mistuning adjustment module calculates the target mistuning bias value using the parameterized structural model, and drives the magneto-rheological damper and the piezoelectric bypass device connected to the antenna support assembly according to the target mistuning bias value. The pre-distortion beam generation module updates the feed phase vector and amplitude weight of the antenna array based on the target mistuning bias value, generates a pre-distortion beam for a non-design working frequency band, and suppresses the side lobe leakage caused by resonance. The leakage spectrum suppression module generates a leakage spectrum mask according to the output of the pre-distortion beam, sets the judgment threshold and transmission time window of the satellite synchronization signal according to the leakage spectrum mask, and shields the signal transmission of the high-risk frequency band. The closed-loop adaptive control module acquires the positioning residual and time delay drift parameters of the satellite positioning result, compares and analyzes the parameters with the leakage spectrum and the shear energy spectrum baseline, inversely updates the parameterized structural model and the target mistuning bias value, and uses the updated parameters in the magneto-rheological damper, the piezoelectric bypass device, and the pre-distortion beam control to form an adaptive closed-loop control process that resists resonance and suppresses side lobe leakage.

2. The satellite synchronous detection signal transmitting device for underwater pipeline with large buried depth according to claim 1, characterized in that, The steps of constructing a low-frequency shear force real-time perception link include: A three-axis shear force sensor with a range of ±5000 Newton and a resolution of 0.05 Newton and a fiber Bragg grating strain sensor with a range of ±3000 micro-strain and a resolution better than 1 micro-strain are arranged at the node position of the antenna support assembly with the highest modal strain energy, and static zero drift test and dynamic sensitivity calibration are completed before installation; The sensor signals are transmitted to the time synchronization processing unit through twisted shielded cable, and after low-pass filtering and multi-scale wavelet packet decomposition to extract low-frequency and high-frequency components, sliding average baseline compensation and fast Fourier transform spectrum analysis are performed, instantaneous shear gradient and structural strain mode are calculated using synchronous data, and low-frequency disturbance key frequency is selected through generalized cross-correlation; The instantaneous shear gradient and structural strain mode are input to construct the shear energy spectrum baseline, and when the deviation value exceeds the threshold, it is determined that the sea current shear state deviates significantly from the steady state.

3. The satellite synchronous signal transmitting device for underwater pipeline with large buried depth according to claim 1, characterized in that, In the construction process of the shear energy spectrum baseline, the running period is not less than 30 days, each time window length is 600 seconds, adaptive spectral clustering algorithm is used to cluster the energy spectrum curves under different sea current conditions, and the most frequently occurring spectrum shape is extracted from the clustering results as the reference spectrum shape of the target sea area.

4. The satellite synchronous detection signal transmitting device for underwater pipeline with large burial depth according to claim 2, characterized in that, The steps of identifying the near-resonance frequency interval according to the shear energy spectrum baseline and establishing the parameterized structure model of the antenna support assembly include: Comparing the shear energy spectrum baseline with the real-time shear energy spectrum point by point in the frequency domain, when the energy density ratio exceeds the positive threshold and lasts for two baseline sampling periods and is within the inherent frequency ± 5% range, it is determined to be in the near-resonance state; In the near-resonance state, the inherent frequency drift is measured by using the fiber Bragg grating strain sensor and the acceleration response signal, and the shear force mutation time is aligned through Hilbert transform, and the measurement accuracy is controlled within 0.01 hertz; The inherent frequency drift is coupled with the deep sea current parameters to build a coupled input set and establish a second-order nonlinear vibration relationship; Based on the finite element analysis results and the coupled input set, a parameterized structure model is established, equivalent stiffness, damping and mass correction variables are introduced, and model parameters are corrected in real time through Kalman filtering to maintain adaptive ability.

5. The satellite synchronous detection signal transmitting device for underwater large buried depth pipeline according to claim 4, characterized in that, The hydrodynamic parameters of the hydrodynamic resistance coefficient and the lift coefficient are obtained by numerical fluid dynamics simulation combined with physical water tank test calibration, and the parameterized structure model receives real-time shear force data, strain data and inherent frequency drift every interval not exceeding 60 seconds during operation, and updates the model parameters in real time.

6. The satellite synchronous detection signal transmitting device for underwater large buried depth pipeline according to claim 1, characterized in that, The steps of calculating the target detuning bias value by using the parameterized structure model and driving the magneto-rheological damper and the piezoelectric bypass device to realize synchronous adjustment of equivalent stiffness and damping include: Input the shear force data, structure strain data, inherent frequency drift and hydrodynamic parameters of the current parameterized structure model, predict the dynamic response and calculate the difference value with the static inherent frequency as the initial estimated value of the target detuning bias value; The initial estimated value is dynamically corrected combined with the real-time modal analysis result to ensure that the difference between the predicted frequency and the actual frequency is not more than 0.02 hertz, and the magneto-rheological damper is driven to adjust the damping force and the piezoelectric bypass device is driven to adjust the equivalent stiffness according to the modified target detuning bias value, and the adjustment proportion is distributed according to the disturbance amplitude; Monitor the dynamic response and feed back to the model, verify the effect, store the optimized value or make secondary adjustment until the preset performance index is reached.

7. The satellite synchronous detection signal transmitting device for underwater large buried depth pipeline according to claim 1, characterized in that, The steps of updating the antenna array feed phase vector and amplitude weight based on the target detuning bias value to generate a pre-distortion beam include: Determine the initial state of the array directivity diagram by using the amplitude and phase response database combined with the corrected target detuning bias value, array geometric layout, element spacing, operating frequency and attitude; Map the target detuning bias value to the resonance risk frequency interval sidelobe suppression target, calculate the phase offset and amplitude change of each element, and generate the corrected feed phase vector and amplitude weight; Adjust the amplitude and phase of each radiating element synchronously through the phase shift controller and the variable attenuator, and perform real-time amplitude and phase verification and secondary fine tuning after adjustment, collect array radiation distribution in the underwater test field to verify the sidelobe suppression effect, and store it as a standard configuration when qualified, and optimize the parameters and repeat the verification when not up to standard.

8. The satellite synchronous detection signal transmitting device for underwater large buried depth pipeline according to claim 7, characterized in that, The steps of generating a leakage spectrum mask according to the pre-distortion beam output and setting a satellite synchronization signal judgment threshold and a transmission time window include: Collect the radiation signal spectrum data of the pre-distortion beam at different azimuth and elevation angles in the whole space, and synchronize with the array operating state time; The measured beam spectrum shape is compared with the designed spectrum shape to identify non-design frequency points with excessive amplitude and generate an adaptive attenuation mask curve to form a leakage spectrum mask; Based on the leakage spectrum mask, an amplitude threshold and a phase offset tolerance are set, and combined with satellite visibility prediction and sea current disturbance prediction, a second-level precision transmission time window is determined; The determination threshold and transmission time window are applied to the running and dynamically monitored and adjusted, and when the leakage approaches the threshold, amplitude and phase fine tuning or delayed transmission are performed, and running data is stored to form a leakage control strategy library.

9. The satellite synchronous detection signal transmitting device for underwater large buried depth pipeline according to claim 8, characterized in that, The steps of collecting positioning residual and time delay drift parameters of satellite positioning results and inversely updating parameterized structure model and target detuning bias value include: Real-time data of positioning residual and time delay drift are obtained and recorded synchronously with environmental parameters at the transmission time; The data are compared with the baseline of leakage spectrum and shear energy spectrum point by point, and multi-source correlation analysis is performed to judge the resonance risk; The analysis results are input to the parameterized structure model to correct the hydrodynamic parameters and structure parameters, and a new target detuning bias value is calculated through iterative optimization; The new target detuning bias value is applied to the magneto-rheological damper, piezoelectric bypass device and antenna array amplitude and phase control, realizing adaptive closed-loop anti-resonance and sub-beam leakage suppression.

10. A method for transmitting a satellite-synchronous detection signal to a pipeline having a large buried depth under water, by using the satellite-synchronous detection signal transmitting apparatus for a pipeline having a large buried depth under water according to any one of claims 1 to 9, characterized in that, The steps include: A low-frequency shear force real-time sensing link is constructed, based on shear force sensors and structure strain sensors arranged on the antenna support assembly, shear gradient and structure strain data under the action of deep sea current are collected, and corresponding shear energy spectrum baseline is generated; According to the shear energy spectrum baseline, the frequency interval in the near resonance state is identified, and the inherent frequency drift is measured, the inherent frequency drift and the hydrodynamic parameters related to shear force are coupled to establish a parameterized structure model of the antenna support assembly; The target detuning bias value is calculated by using the parameterized structure model, and the magneto-rheological damper and piezoelectric bypass device connected with the antenna support assembly are driven according to the target detuning bias value; Based on the target detuning bias value, the feeding phase vector and amplitude weight of the antenna array are updated to generate a pre-distortion beam for the non-design working frequency band, and the sub-beam leakage caused by resonance is suppressed; According to the output of the pre-distortion beam, a leakage spectrum mask is generated, and based on the leakage spectrum mask, a determination threshold and a transmission time window of satellite synchronization signal are set to shield the signal transmission of high-risk frequency band; The positioning residual and time delay drift parameters of satellite positioning results are collected, the parameters are compared and analyzed with the leakage spectrum and shear energy spectrum baseline, the parameterized structure model and target detuning bias value are inversely updated, and the updated parameters are used in the control of magneto-rheological damper, piezoelectric bypass device and pre-distortion beam, forming an adaptive closed-loop control process for anti-resonance and sub-beam leakage suppression.

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