GNSS-IR Multi-Station Fusion Water Level Monitoring Method, Device, Medium and Equipment

Abstract

The present application discloses a GNSS-IR multi-station integrated water level monitoring method, device, medium and equipment. The method includes: collecting GNSS observation data, calculating the signal-to-noise ratio of satellite signals at each epoch, as well as the corresponding azimuth information and altitude information; determining a low altitude angle range based on the azimuth information and altitude information, extracting the signal-to-noise ratio sequence and altitude angle sequence of each station based on the low altitude angle range, and obtaining a signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence; performing spectral analysis on the signal-to-noise ratio residual sequence to obtain a frequency analysis result; converting the true water level height into an absolute water level result; estimating an initial water level value, calculating a water level inversion observation value according to the altitude angle sequence and the position information of the station, calculating a weight based on the water level inversion observation value, updating the initial water level value through the weight and performing multiple iterations until a preset termination condition is satisfied, and obtaining a final water level estimation result. The present application can realize real-time and accurate inversion of large water level changes.

Description

Technical Field

[0001] This application relates to the technical field of water conservancy projects, and particularly to a GNSS-IR multi-station integrated water level monitoring method, device, storage medium, and electronic device. Background Art

[0002] The Global Navigation Satellite Systems-Interferometry Reflectometry (GNSS-IR) technology is an innovative remote sensing method. By analyzing the interference delay between the L-band signals transmitted by the Global Navigation Satellite System (GNSS) and the surface reflection signals, it provides a new monitoring solution for the monitoring of surface physical characteristics. The development of GNSS-IR technology benefits from the wide coverage of the GNSS satellite constellation and the rapid growth of the application of GNSS receivers, providing a stable and rich data source for GNSS-IR applications.

[0003] Among the many applications of GNSS-IR technology, water level monitoring is particularly prominent, marking the expansion of GNSS technology from traditional navigation and positioning to "GNSS+" multi-field applications. Since it was confirmed in 2000 that GNSS receivers can be used as effective "remote sensing water level gauges", the GNSS-IR water level monitoring technology has brought a new solution to the field of hydrological monitoring with its non-contact measurement, high spatio-temporal resolution, and high-precision absolute reference monitoring services.

[0004] The accuracy guarantee of GNSS-IR water level monitoring technology depends on rich and reliable satellite arc retrieval values. However, with the continuous expansion of the technical application scenarios, in some specific monitoring environments, such as rivers with a narrow water surface reflection area, pumped storage power stations with large daily water level fluctuations, etc., there are fewer multipath signals from the water surface reflection, and the number of available satellite arcs for a single station is limited, making it difficult to comprehensively capture the characteristics of water level changes. In addition, the receiver's ability to receive signals from different satellite systems has also become a key factor restricting the number of GNSS-IR inversion points. Due to factors such as construction time and construction requirements, some shore-based GNSS stations can only receive data from a single or partial satellite system, failing to fully utilize the advantages of GNSS multi-systems and multi-frequencies. Summary of the Invention

[0005] The embodiments of this application provide a GNSS-IR multi-station integrated water level monitoring method, device, storage medium, and electronic device, which can improve the accuracy of water level inversion and water level estimation, and achieve a large-scale and comprehensive monitoring of water levels.

[0006] The embodiments of this application provide a GNSS-IR multi-station integrated water level monitoring method, including:

[0007] Collect GNSS observation data, calculate the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and altitude information of the signal-to-noise ratio;

[0008] Determine the low elevation angle range based on the azimuth information and the altitude information, extract the signal-to-noise ratio sequence and the elevation angle sequence of each station based on the low elevation angle range, and obtain the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence;

[0009] Perform spectral analysis on the signal-to-noise ratio residual sequence to obtain the frequency analysis result;

[0010] Convert the true water level height measured by each station into the absolute water level result;

[0011] Estimate the initial water level value, calculate the water level inversion observation value according to the elevation angle sequence and the position information of the station, calculate the weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until the preset termination condition is met to obtain the final water level estimation result.

[0012] Further, in the above GNSS-IR multi-station integrated water level monitoring method, the step of collecting GNSS observation data, calculating the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and altitude information of the signal-to-noise ratio includes:

[0013] Collect GNSS observation data through a GNSS receiver and collect the satellite ephemeris file corresponding to the GNSS observation data;

[0014] Based on the GNSS observation data and the satellite ephemeris file, calculate the position of the satellite at each epoch and determine the azimuth angle and altitude angle of each satellite;

[0015] Calculate the signal-to-noise ratio of all satellite signals at each epoch, match the signal-to-noise ratio with the azimuth angle and altitude angle to obtain the corresponding azimuth information and altitude information of the signal-to-noise ratio.

[0016] Further, in the above GNSS-IR multi-station integrated water level monitoring method, the step of determining the low elevation angle range based on the azimuth information and the altitude information, extracting the signal-to-noise ratio sequence and the elevation angle sequence of each station based on the low elevation angle range, and obtaining the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence includes:

[0017] Calculate the Fresnel effective reflection area based on the azimuth information and the altitude information, calculate the low elevation angle range based on the Fresnel effective reflection area, and extract the signal-to-noise ratio sequence and the elevation angle sequence of each station based on the low elevation angle range;

[0018] Screen the SNR sequence based on the low elevation angle range;

[0019] Perform quadratic polynomial fitting on the screened SNR sequence to obtain the SNR residual sequence.

[0020] Further, in the above GNSS-IR multi-station integrated water level monitoring method, wherein, the performing spectral analysis on the SNR residual sequence to obtain a frequency analysis result includes:

[0021] Set the constraint conditions for spectral analysis;

[0022] Use the Lomb periodogram method to perform spectral analysis on the SNR residual sequence to obtain a frequency analysis result;

[0023] Screen the frequency analysis result.

[0024] Further, in the above GNSS-IR multi-station integrated water level monitoring method, wherein, the converting the true water level heights measured by each of the stations into absolute water level results includes:

[0025] After eliminating the errors in the GNSS propagation process, obtain the three-dimensional coordinate information of the station; wherein, the three-dimensional coordinate information includes the station height data of the station;

[0026] Based on the station height data of the station, establish a water level measurement reference plane;

[0027] According to the water level measurement reference plane, convert the true water level heights measured by each of the stations into absolute water level results.

[0028] Further, in the above GNSS-IR multi-station integrated water level monitoring method, wherein, the estimating the initial water level value, calculating the water level inversion observation value according to the elevation angle sequence and the position information of the station, calculating the weight based on the water level inversion observation value, updating the initial water level value through the weight and performing multiple iterations until a preset termination condition is satisfied to obtain the final water level estimation result includes:

[0029] Estimate the initial water level value by the least squares method within the water level estimation window;

[0030] Construct an observation equation based on the elevation angle sequence and the position information of the station, and inversely calculate to obtain the water level inversion observation value;

[0031] Calculate the peak signal-to-noise ratio for the water level inversion observation value according to the frequency analysis result;

[0032] Calculate the weight according to the peak signal-to-noise ratio;

[0033] Update the initial water level value with the weight and perform multiple iterations until a preset termination condition is met to obtain the final water level estimation result.

[0034] Further, in the above GNSS-IR multi-station integrated water level monitoring method, the method further includes:

[0035] Calculate a new weight through an equivalent weight function, and the new weight is used to update the historical water level value.

[0036] An embodiment of the present application also provides a GNSS-IR multi-station integrated water level monitoring device, including:

[0037] An acquisition module, configured to collect GNSS observation data, calculate the signal-to-noise ratio of all satellite signals at each epoch, and the azimuth information and altitude information corresponding to the signal-to-noise ratio;

[0038] An extraction module, configured to determine a low elevation angle range based on the azimuth information and the altitude information, extract the signal-to-noise ratio sequence and elevation angle sequence of each station based on the low elevation angle range, and obtain a signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence;

[0039] An analysis module, configured to perform spectral analysis on the signal-to-noise ratio residual sequence to obtain a frequency analysis result;

[0040] A conversion module, configured to convert the true water level height measured by each station into an absolute water level result;

[0041] A water level estimation module, configured to estimate an initial water level value, calculate a water level inversion observation value according to the elevation angle sequence and the position information of the station, calculate a weight based on the water level inversion observation value, update the initial water level value with the weight and perform multiple iterations until a preset termination condition is met to obtain a final water level estimation result.

[0042] An embodiment of the present application also provides a computer-readable storage medium, in which multiple instructions are stored, and the instructions are suitable for being loaded by a processor to execute any one of the above GNSS-IR multi-station integrated water level monitoring methods.

[0043] An embodiment of the present application also provides an electronic device, including a processor and a memory, the processor is electrically connected to the memory, the memory is used to store instructions and data, and the processor is used for the steps in any one of the above GNSS-IR multi-station integrated water level monitoring methods.

[0044] The GNSS-IR multi-station fusion water level monitoring method, device, storage medium and electronic device provided by the present application first estimates the initial water level value, then calculates the weight, updates the initial water position through the weight and performs multiple iterations to obtain the final water level estimation result. The present application uses multi-site data for water level inversion, and can realize real-time and accurate inversion of large water level changes, meeting the requirements for water level monitoring in the hydrological monitoring field of pumped storage power stations. Description of the Drawings

[0045] The following will combine the drawings in the embodiments of the present application, and will clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0046] Figure 1 It is a flowchart of the GNSS-IR multi-station fusion water level monitoring method provided by the embodiment of the present application.

[0047] Figure 2 It is another flowchart of the GNSS-IR multi-station fusion water level monitoring method provided by the embodiment of the present application.

[0048] Figure 3 It is a schematic diagram for comparing the water level measurement result and the multi-station fusion inversion result provided by the embodiment of the present application.

[0049] Figure 4 It is a schematic diagram of the structure of the GNSS-IR multi-station fusion water level monitoring device provided by the embodiment of the present application.

[0050] Figure 5 It is a schematic diagram of the structure of the electronic device provided by the embodiment of the present application.

[0051] Figure 6 It is another schematic diagram of the structure of the electronic device provided by the embodiment of the present application. Detailed Embodiments

[0052] The following will combine the drawings in the embodiments of the present application, and will clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0053] The embodiments of the present application provide a GNSS-IR multi-station fusion water level monitoring method, device, storage medium and electronic device. A GNSS-IR multi-station fusion water level monitoring device provided by the embodiments of the present application can be integrated into an electronic device, and the electronic device can be a device such as a terminal, a server, etc. Among them, the terminal can include a tablet computer, a notebook computer, a personal computer (PC), a micro processing box, or other devices, etc.

[0054] Please refer to Figure 1 With Figure 2 , Figure 1 is a flowchart of the GNSS-IR multi-station fusion water level monitoring method provided by the embodiments of the present application. Figure 1 is another flowchart of the GNSS-IR multi-station fusion water level monitoring method provided by the embodiments of the present application, which is applied to an electronic device. The GNSS-IR multi-station fusion water level monitoring method includes the following steps:

[0055] S1. Collect GNSS observation data, and calculate the signal-to-noise ratio of all satellite signals at each epoch, as well as the azimuth information and altitude information corresponding to the signal-to-noise ratio.

[0056] In one embodiment, step S1 may include the following steps:

[0057] S11. Collect GNSS observation data through a GNSS receiver, and collect the satellite ephemeris file corresponding to the GNSS observation data.

[0058] Specifically, organize the GNSS observation data collected by the GNSS receiver to ensure the integrity and accuracy of the GNSS observation data. By carefully reading and analyzing these data files, detailed information of each observation epoch can be extracted, including satellite ID, signal frequency, observation time, pseudorange, carrier phase, and signal-to-noise ratio (SNR). At the same time, collect the satellite ephemeris file at the time point corresponding to the GNSS observation data, where the satellite ephemeris file contains the precise orbital parameters of the satellite.

[0059] S12. Based on the GNSS observation data and the satellite ephemeris file, calculate the position of the satellite at each epoch, and determine the azimuth angle and altitude angle of each satellite.

[0060] Specifically, use the single-point positioning or precise single-point positioning principle, combined with the GNSS observation data and satellite ephemeris file information (broadcast ephemeris or precise ephemeris), to calculate the position of the satellite at each epoch. Determine the azimuth angle and altitude angle of each satellite relative to the receiver through the signal recorded by the GNSS receiver. Among them, the azimuth angle indicates the azimuth of the satellite relative to the station, while the altitude angle reflects the angle of the satellite above the station.

[0061] S13. Calculate the signal-to-noise ratio (SNR) of all satellite signals at each epoch, match the SNR with the azimuth angle and elevation angle, and obtain the corresponding azimuth information and elevation information for the SNR.

[0062] Specifically, according to the relationship between the SNR data and the calculated elevation angle, match the SNR values with the corresponding azimuth angles and elevation angles in order to further analyze and interpret the influence of the signal characteristics (analyze the mathematical relationship between the SNR sequence and the elevation angle sequence) on the monitoring target.

[0063] S2. Determine the low elevation angle range based on the azimuth information and elevation information, extract the SNR sequence and elevation angle sequence of each station based on the low elevation angle range, and obtain the SNR residual sequence based on the SNR sequence.

[0064] In one embodiment, step S2 may include the following steps:

[0065] S21. Calculate the Fresnel effective reflection area based on the azimuth information and elevation information, calculate the low elevation angle range based on the Fresnel effective reflection area, and extract the SNR sequence and elevation angle sequence of each station based on the low elevation angle range.

[0066] Specifically, according to the Huygens - Fresnel principle, the propagation path of electromagnetic waves is not a single straight line, but forms an extended area between the wave source and the receiver, which is called the Fresnel zone. This area can be described as:

[0067]

[0068] where represents the wavelength of the satellite signal frequency band, is the coordinate of the water surface reflection point, , , are respectively the center and the major and minor radii of the first Fresnel ellipse. is the water surface reflection height, is the satellite elevation angle.

[0069] S22. Screen the SNR sequence based on the low elevation angle range.

[0070] After determining the effective reflection area and the low elevation angle range, screen the SNR sequences collected at each station, and retain those sequences within the low elevation angle range.

[0071] S23. Perform a quadratic polynomial fitting on the screened SNR sequence to obtain the SNR residual sequence.

[0072] The quadratic polynomial fitting method is used to analyze the trend of the SNR sequence to eliminate the fixed trend change caused by the direct signal. Through this process, the SNR residual sequence of the reflected signal fluctuation can be obtained, and these residual sequences are the key data for subsequent analysis and water level inversion.

[0073] Specifically, the trend term of the direct signal in the SNR sequence is removed to obtain the SNR residual sequence ( ), which can be expressed as a function of the path difference as follows:

[0074]

[0075] where and are the amplitude and phase of the water surface reflection height under the static assumption.

[0076] S3. Perform spectral analysis on the SNR residual sequence to obtain the frequency analysis result.

[0077] In one embodiment, step S3 includes the following steps:

[0078] S31. Set the constraint conditions for spectral analysis.

[0079] Before analyzing the SNR residual sequence, first set the constraint conditions for spectral analysis, which may include the physical characteristics of the signal, the expected frequency range, environmental factors, the prior water surface height threshold, the azimuth angle threshold, and the elevation angle threshold, etc., to ensure that the analysis process conforms to the actual monitoring target and environmental background.

[0080] S32. Use the Lomb periodogram method to perform spectral analysis on the SNR residual sequence to obtain the frequency analysis result.

[0081] Apply the Lomb periodogram method to perform spectral analysis on the SNR residual sequence. This method is suitable for frequency analysis of non-uniformly sampled data and can effectively identify the periodic components in the signal, thereby extracting the dominant frequency reflecting the water level change.

[0082] Specifically, for the non-uniformly sampled sequence, it can effectively extract the weak periodic signal of the sequence, suppress the false signal caused by the non-uniform time domain, and can give the false alarm probability and significance of different frequency components. For the SNR residual sequence , the LSP power spectrum can be expressed as:

[0083]

[0084] Among them, is a time translation invariant.

[0085] S33, screen the frequency analysis results.

[0086] After obtaining the frequency analysis results, strict quality control is carried out to screen out the frequency analysis results that meet the expected physical characteristics and statistical significance, including evaluating the stability, reliability of the frequency, and consistency with known environmental changes, ensuring that the finally retained frequency analysis results can effectively reflect the true state of the monitoring object.

[0087] S4, convert the true water level height measured at each station into an absolute water level result.

[0088] In one embodiment, step S4 may include:

[0089] S41, after performing differential elimination or correction on the error terms in the GNSS propagation process, obtain the three-dimensional coordinate information of the station; among them, the three-dimensional coordinate information includes the station height data of the station.

[0090] S42, based on the station height data of the station, establish a water level measurement reference plane.

[0091] Based on the station height data of the station, establish a unified water level measurement reference plane. This reference plane will serve as a common reference for water level monitoring and water level gauge comparison, and at the same time establish the water level data between different stations on a unified basis.

[0092] S43, according to the water level measurement reference plane, convert the true water level height measured at each station into an absolute water level result.

[0093] According to the unified water level reference, standardize the water level data collected at each station. This step involves adjusting the original water level observation values to make them relative to the unified reference plane, thereby achieving the consistency and accuracy of the water level data between different stations.

[0094] Benefiting from the ability of the GNSS device to simultaneously obtain the absolute position of the antenna phase center the true water level height measured by the GNSS-IR technology is converted to an absolute reference to obtain an absolute water level result , and the conversion relationship is:

[0095]

[0096] S5. Estimate the initial water level value, calculate the water level inversion observation value according to the elevation angle sequence and the position information of the measuring station, calculate the weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until the preset termination condition is met to obtain the final water level estimation result.

[0097] In one embodiment, step S5 includes the following steps:

[0098] S51. Within the water level estimation window, estimate the initial water level value by the least squares method.

[0099] In order to comprehensively utilize all the inversion results when multiple GNSS devices monitor the water level of the same water surface area, this application performs multi-station fusion based on the robust estimation method. First, select a suitable water level estimation time window , and it can be considered that the water level change within this window is a linear change. Then determine the reference water level value corresponding to the reference epoch , then for other epochs the water level value to be solved can be represented by the reference water level value as follows:

[0100]

[0101] where is a parameter. Among them, the reference water level value and the water level value to be solved are both absolute water level results.

[0102] S52. Construct an observation equation and invert to obtain the water level inversion observation value.

[0103] Assume that there are absolute water level results of GNSS measuring stations within this water level estimation time window, and the th measuring station has inverted successful absolute water level results. Then, establish the following observation equation within this time window:

[0104]

[0105] where , , respectively represent the static water level assumed instantaneous height value, the tangent value of the elevation angle, and the change rate of the elevation angle of the th available arc segment of the th measuring station, and represents the The absolute position of the antenna phase center of each measuring station, and the meanings of other symbols are similar by analogy. For the convenience of discussion, the above formula can be abbreviated as:

[0106]

[0107] Among them, the observation value matrix , the coefficient matrix , the unknown parameter vector , the constant matrix .

[0108] Among them, the observation value matrix is the water level inversion observation value obtained by inversion.

[0109] S53. According to the frequency analysis result, calculate the peak signal-to-noise ratio for the water level inversion observation value.

[0110] The P / N value (peak signal-to-noise ratio) of each water level inversion observation value according to the frequency analysis result.

[0111] S54. Calculate the weight according to the peak signal-to-noise ratio.

[0112] Specifically, it can be calculated by the following formula:

[0113]

[0114] Among them, represents the P / N value of the water level inversion observation value of the th measuring station and the th available arc segment.

[0115] S55. Update the initial water level value through the weight and perform multiple iterations until the preset termination condition is satisfied to obtain the final water level estimation result.

[0116] According to the weighted least squares principle, it can be obtained:

[0117]

[0118] Among them, represents the total number of water level inversion results, , , are the initially estimated unknown parameters, residuals, and unit weight errors, which are also the initial input values for the subsequent robust estimation weight selection and iteration method.

[0119] In order to resist the influence of abnormal gross error results caused by different equipment, environmental conditions, and observation errors on the final result, the present application uses the IGGⅢ equivalent weight function to identify and distinguish the error types of different observation values, as shown in the following formula:

[0120]

[0121] Among them, represents the weight of the th water level inversion observation value; is the standardized residual, which refers to the ratio of the updated value of each water level observation value to the mean square error; , and are the corresponding harmonic coefficients. In this application, .

[0122] Update the weight through the above formula. As shown in the above formula, for the normal section where the standardized residual is less than , the original weight is still adopted. For the elimination section with significantly larger residuals, zero weight (or approximate zero weight) is used for processing, and for other residuals, the weight reduction method is used for estimation. After each calculation to determine the new weight, continue the iteration. The new weight is used to update the historical water level value (i.e., the water level inversion observation value obtained in the previous round of iteration) until the termination condition is met. The termination condition is:

[0123]

[0124] Among them, is the residual of the th parameter in the rd iteration, is the preset termination threshold, which is set to 0.001m in this application.

[0125] This application first estimates the initial water level value, then calculates the weight, updates the initial water position through the weight and conducts multiple iterations to obtain the final water level estimation result. This application uses multi-site data for water level inversion, and can achieve real-time and accurate inversion of large water level changes, meeting the requirements for water level monitoring in the hydrological monitoring field of pumped storage power stations.

[0126] In order to further analyze the accuracy and reliability of the GNSS-IR water level inversion results of multi-station fusion, this paper conducts a comparative verification based on the field measurement results of water level gauges. Figure 3 is the schematic diagram of the comparison between the water level measurement results provided by the embodiments of this application and the multi-station fusion inversion results. As Figure 3The water level results in January 2018 are shown. The black line is the measurement result of the water level gauge, and the red dots are the inversion results of multi-station fusion. The consistency between the fusion inversion results and the measurement results of the water level gauge is relatively high. The standard deviation between them is 1.13 m. Compared with the water level monitoring accuracies of 1.47 m, 1.92 m, and 1.84 m during the inversion of single stations S191, S171, and S071, the reliability of the results is greatly improved. At the same time, when using the multi-station fusion GNSS-IR water level monitoring method to invert the water level of Xilongchi Upper Reservoir, the correlation between the fusion result and the 1-hour measurement result of the water level gauge is as high as 98.3%. Compared with the water level inversion of a single station, the accuracy and reliability of the results are improved. Therefore, the multi-station fusion GNSS-IR water level monitoring method can integrate the information of multiple stations and improve the reliability of water level inversion. In the future, GNSS devices can be used to explore the response relationship between the long-term deformation characteristics of water conservancy projects and the long-term water level changes simultaneously.

[0127] According to the method described in the above embodiments, this embodiment will be further described from the perspective of the GNSS-IR multi-station fusion water level monitoring device. The GNSS-IR multi-station fusion water level monitoring device can be specifically implemented as an independent entity or integrated in an electronic device. The electronic device can be a device such as a terminal or a server. Among them, the terminal can include a tablet computer, a notebook computer, a personal computer (PC), a microprocessing box, or other devices, etc.

[0128] Please refer to Figure 4 , Figure 4 Specifically describes the GNSS-IR multi-station fusion water level monitoring device provided in the embodiments of the present application, which is applied to an electronic device. The GNSS-IR multi-station fusion water level monitoring device may include:

[0129] An acquisition module, configured to collect GNSS observation data, calculate the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and elevation information of the signal-to-noise ratio;

[0130] An extraction module, configured to determine a low elevation angle range based on the azimuth information and the elevation information, extract the signal-to-noise ratio sequence and elevation angle sequence of each station based on the low elevation angle range, and obtain a signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence;

[0131] An analysis module, configured to perform spectral analysis on the signal-to-noise ratio residual sequence to obtain a frequency analysis result;

[0132] A conversion module, configured to convert the true water level height measured by each station into an absolute water level result;

[0133] A water level estimation module, which is used to estimate the initial water level value, calculate the water level inversion observation value according to the elevation angle sequence and the position information of the measuring station, calculate the weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until a preset termination condition is met, and obtain the final water level estimation result.

[0134] In specific implementation, each of the above modules and / or units can be implemented as an independent entity, or can be combined arbitrarily and implemented as the same or several entities. For the specific implementation of each of the above modules and / or units, reference can be made to the foregoing method embodiments, and the beneficial effects that can be specifically achieved can also be referred to the beneficial effects in the foregoing method embodiments, which will not be elaborated herein.

[0135] In addition, the embodiment of the present application also provides an electronic device, which can be a device such as a computer or a tablet computer. As Figure 5 shown, the electronic device 400 includes a processor 401 and a memory 402. Among them, the processor 401 is electrically connected to the memory 402.

[0136] The processor 401 is the control center of the electronic device 400, connects various parts of the entire electronic device by using various interfaces and lines, executes various functions of the electronic device and processes data by running or loading the application programs stored in the memory 402 and calling the data stored in the memory 402, so as to monitor the electronic device as a whole.

[0137] In this embodiment, the processor 401 in the electronic device 400 will load the instructions corresponding to the processes of one or more application programs into the memory 402 according to the following steps, and the processor 401 will run the application programs stored in the memory 402 to implement various functions:

[0138] Collect GNSS observation data, and calculate the signal-to-noise ratio of all satellite signals at each epoch, as well as the azimuth information and elevation information corresponding to the signal-to-noise ratio;

[0139] Determine the low elevation angle range based on the azimuth information and the elevation information, extract the signal-to-noise ratio sequence and elevation angle sequence of each measuring station based on the low elevation angle range, and obtain the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence;

[0140] Perform spectral analysis on the signal-to-noise ratio residual sequence to obtain the frequency analysis result;

[0141] Convert the true water level height measured by each of the measuring stations into an absolute water level result;

[0142] Estimate the initial water level value, calculate the water level inversion observation value according to the elevation angle sequence and the position information of the measuring station, calculate the weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until a preset termination condition is met, and obtain the final water level estimation result.

[0143] The electronic device can implement the steps in any one of the embodiments of the GNSS-IR multi-station integrated water level monitoring method provided in this application. Therefore, it can achieve the beneficial effects that any GNSS-IR multi-station integrated water level monitoring method provided in the embodiments of the present invention can achieve. For details, please refer to the previous embodiments and will not be elaborated here.

[0144] Figure 6 The specific structural block diagram of the electronic device provided in the embodiments of the present invention is shown. The electronic device can be used to implement the GNSS-IR multi-station integrated water level monitoring method provided in the above embodiments. The electronic device 500 can be a device such as a terminal or a server. Among them, the terminal can include a tablet computer, a notebook computer, a personal computer (PC), a microprocessing box, or other devices.

[0145] The RF circuit 510 is used to receive and transmit electromagnetic waves, enabling the mutual conversion between electromagnetic waves and electrical signals, so as to communicate with a communication network or other devices. The RF circuit 510 may include various existing circuit components for performing these functions. For example, antennas, radio frequency transceivers, digital signal processors, encryption / decryption chips, subscriber identity module (SIM) cards, memories, and so on. The RF circuit 510 can communicate with various networks such as the Internet, enterprise intranets, wireless networks, or communicate with other devices through a wireless network. The above-mentioned wireless networks may include cellular phone networks, wireless local area networks, or metropolitan area networks. The above-mentioned wireless networks can use various communication standards, protocols, and technologies, including but not limited to Global System for Mobile Communication (GSM), Enhanced Data GSM Environment (EDGE), Wideband Code Division Multiple Access (WCDMA), Code Division Access (CDMA), Time Division Multiple Access (TDMA), Wireless Fidelity (Wi-Fi) (such as Institute of Electrical and Electronics Engineers standards IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, and / or IEEE 802.11n), Voice over Internet Protocol (VoIP), Worldwide Interoperability for Microwave Access (Wi-Max), other protocols for email, instant messaging, and short messages, and any other suitable communication protocols, and may even include those protocols that have not yet been developed currently.

[0146] The memory 520 can be used to store software programs and modules, such as the corresponding program instructions / modules in the above embodiments. The processor 580 executes various functional applications and data processing by running the software programs and modules stored in the memory 520, that is, to implement functions such as taking pictures with the front camera, processing the captured images, and switching the display colors of the display content on the display screen. The memory 520 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some instances, the memory 520 may further include a memory remotely disposed relative to the processor 580, and these remote memories can be connected to the electronic device 500 through a network. Examples of the above network include but are not limited to the Internet, enterprise intranets, local area networks, mobile communication networks, and combinations thereof.

[0147] The input unit 530 can be used to receive input digital or character information, as well as generate a keyboard and a mouse related to user settings and function controls.

[0148] The display unit 540 can be used to display information input by the user or information provided to the user, as well as various graphical user interfaces, and these graphical user interfaces can be composed of graphics, texts, icons, videos, and any combination thereof. The display unit 540 may include a display panel 541. Optionally, the display panel 541 can be configured in the form of an LCD (Liquid Crystal Display) or an OLED (Organic Light-Emitting Diode).

[0149] The audio circuit 560, the speaker 561, and the microphone 562 can provide an audio interface between the user and the electronic device 500. The audio circuit 560 can transmit the electrical signal converted from the received audio data to the speaker 561, and the speaker 561 converts it into a sound signal for output; on the other hand, the microphone 562 converts the collected sound signal into an electrical signal, which is received by the audio circuit 560 and then converted into audio data. After the audio data is output to the processor 580 for processing, it is sent to another terminal, for example, through the RF circuit 510, or the audio data is output to the memory 520 for further processing. The audio circuit 560 may also include an earphone jack to provide communication between the peripheral earphone and the electronic device 500.

[0150] The electronic device 500 can help the user receive requests, send information, etc. through the transmission module 570 (such as a Wi-Fi module), and it provides the user with wireless broadband Internet access. Although the transmission module 570 is shown in the figure, it can be understood that it does not belong to the essential components of the electronic device 500 and can be omitted completely within the scope of not changing the essence of the invention according to needs.

[0151] The processor 580 is the control center of the electronic device 500, connecting various parts of the entire mobile phone through various interfaces and circuits. By running or executing software programs and / or modules stored in the memory 520, and by calling the data stored in the memory 520, it executes various functions of the electronic device 500 and processes data, thereby monitoring the electronic device as a whole. Optionally, the processor 580 may include one or more processing cores; in some embodiments, the processor 580 may integrate an application processor and a modem processor. Among them, the application processor mainly processes the operating system, user interface, application programs, etc., and the modem processor mainly processes wireless communication. It can be understood that the above-mentioned modem processor may not be integrated into the processor 580 either.

[0152] The electronic device 500 also includes a power source 590 (such as a battery) for powering each component. In some embodiments, the power source can be logically connected to the processor 580 through a power management system, so as to realize functions such as management of charging, discharging, and power consumption management through the power management system. The power source 590 may also include any components such as one or more DC or AC power sources, a recharge system, a power failure detection circuit, a power converter or inverter, and a power status indicator.

[0153] Although not shown, the electronic device 500 also includes a camera (such as a front camera and a rear camera), a Bluetooth module, etc., which will not be elaborated here. Specifically, in this embodiment, the display unit of the electronic device is a touch screen display, and the mobile terminal also includes a memory, and one or more programs, where one or more programs are stored in the memory and are configured to be executed by one or more processors. One or more programs include instructions for performing the following operations:

[0154] Collect GNSS observation data, calculate the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and altitude information of the signal-to-noise ratio;

[0155] Determine the low elevation angle range based on the azimuth information and the altitude information, extract the signal-to-noise ratio sequence and elevation angle sequence of each station based on the low elevation angle range, and obtain the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence;

[0156] Perform spectral analysis on the signal-to-noise ratio residual sequence to obtain a frequency analysis result;

[0157] Convert the true water level height measured by each station into an absolute water level result;

[0158] Estimate the initial water level value, calculate the water level inversion observation value according to the altitude angle sequence and the position information of the measuring station, calculate the weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until the preset termination condition is satisfied, and obtain the final water level estimation result.

[0159] In specific implementation, each of the above modules can be implemented as an independent entity, or can be combined arbitrarily and implemented as the same or several entities. For the specific implementation of each of the above modules, reference can be made to the foregoing method embodiments, which will not be elaborated herein.

[0160] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructions, or the relevant hardware can be controlled by instructions. The instructions can be stored in a computer-readable storage medium and loaded and executed by a processor. For this purpose, an embodiment of the present invention provides a storage medium in which multiple instructions are stored, and the instructions can be loaded by a processor to execute the steps of any one of the GNSS-IR multi-station fusion water level monitoring methods provided by the embodiments of the present invention.

[0161] Among them, the computer-readable storage medium may include: read-only memory (ROM, Read Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk, etc.

[0162] Since the instructions stored in the storage medium can execute the steps in any one of the GNSS-IR multi-station fusion water level monitoring methods provided by the embodiments of the present invention, the beneficial effects that can be achieved by any of the GNSS-IR multi-station fusion water level monitoring methods provided by the embodiments of the present invention can be realized. For details, refer to the foregoing embodiments, which will not be elaborated herein.

[0163] The above has introduced in detail a GNSS-IR multi-station fusion water level monitoring method, device, storage medium and electronic device provided by the embodiments of the present application. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A GNSS-IR multi-station integrated water level monitoring method, characterized in that, The method includes: Collect GNSS observation data, calculate the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and elevation information of the signal-to-noise ratio; Determine the low elevation angle range based on the azimuth information and the elevation information, extract the signal-to-noise ratio sequence and the corresponding elevation angle sequence of each station based on the low elevation angle range, and obtain the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence; Perform spectral analysis on the signal-to-noise ratio residual sequence to obtain the frequency analysis result, including: setting the constraint conditions for spectral analysis; using the Lomb periodogram method to perform spectral analysis on the signal-to-noise ratio residual sequence to obtain the frequency analysis result; screening the frequency analysis result; Convert the true water level heights measured by multiple stations facing the same water area into the absolute water level results of a unified water level reference, including: eliminating the errors in the GNSS propagation process and obtaining the three-dimensional coordinate information of the station; where the three-dimensional coordinate information includes the station height data of the station; based on the station height data of the station, establish a water level measurement reference plane; according to the water level measurement reference plane, convert the true water level heights measured by each station into absolute water level results; Estimate the initial water level value, calculate the water level inversion observation value according to the elevation angle sequence and the position information of the station, calculate the weight based on the water level inversion observation value and the peak signal-to-noise ratio, update the initial water level value through the weight and perform multiple iterations until the preset termination condition is met to obtain the final water level estimation result; the steps to obtain the final water level estimation result include: Estimate the initial water level value by the least squares method within the water level estimation window; Construct an observation equation based on the elevation angle sequence and the position information of the station, and inversely calculate to obtain the water level inversion observation value; Calculate the peak signal-to-noise ratio for the water level inversion observation value according to the screened frequency analysis result; Calculate the weight according to the peak signal-to-noise ratio: Among them, represents the P / N value of the water level inversion observation of the th available arc segment at the th station; Update the initial water level value through the weight and perform multiple iterations until the preset termination condition is met to obtain the final water level estimation result.

2. The GNSS-IR multi-station integrated water level monitoring method according to claim 1, characterized in that The step of collecting GNSS observation data, calculating the signal-to-noise ratio of all satellite signals at each epoch, and the corresponding azimuth information and elevation information of the signal-to-noise ratio includes: Collect GNSS observation data through a GNSS receiver and collect the satellite ephemeris file corresponding to the GNSS observation data; Based on the GNSS observation data and the satellite ephemeris file, calculate the position of the satellite at each epoch, and determine the azimuth angle and elevation angle of each satellite; Calculate the signal-to-noise ratio of all satellite signals at each epoch, match the signal-to-noise ratio with the azimuth angle and elevation angle, and obtain the corresponding azimuth information and elevation information of the signal-to-noise ratio.

3. The GNSS-IR multi-station integrated water level monitoring method according to claim 1, wherein The step of determining the low elevation angle range based on the azimuth information and the elevation information, extracting the signal-to-noise ratio sequence and elevation angle sequence of each station based on the low elevation angle range, and obtaining the signal-to-noise ratio residual sequence based on the signal-to-noise ratio sequence includes: Calculate the Fresnel effective reflection region based on the azimuth information and the altitude information, calculate the low elevation angle range based on the Fresnel effective reflection region, and extract the SNR sequence and the elevation angle sequence of each station based on the low elevation angle range; Filter the SNR sequence based on the low elevation angle range; Perform a quadratic polynomial fitting on the filtered SNR sequence to obtain the SNR residual sequence.

4. The GNSS-IR multi-station fusion water level monitoring method according to claim 1, characterized in that, The method further includes: Calculate a new weight through an equivalent weight function, and the new weight is used to update the historical water level value.

5. A GNSS-IR multi-station integrated water level monitoring device, which is used to implement the GNSS-IR multi-station integrated water level monitoring method described in claim 1, and is characterized in that, Include: An acquisition module, configured to collect GNSS observation data, calculate the SNR of all satellite signals at each epoch, and the azimuth information and altitude information corresponding to the SNR; An extraction module, configured to determine a low elevation angle range based on the azimuth information and the altitude information, extract the SNR sequence and the elevation angle sequence of each station based on the low elevation angle range, and obtain the SNR residual sequence based on the SNR sequence; An analysis module, configured to perform a spectral analysis on the SNR residual sequence to obtain a frequency analysis result; A conversion module, configured to convert the true water level height measured by each station into an absolute water level result; A water level estimation module, configured to estimate an initial water level value, calculate a water level inversion observation value according to the elevation angle sequence and the position information of the station, calculate a weight based on the water level inversion observation value, update the initial water level value through the weight and perform multiple iterations until a preset termination condition is met, and obtain a final water level estimation result.

6. A computer-readable storage medium, characterized in that Multiple instructions are stored in the computer-readable storage medium, and the instructions are adapted to be loaded by a processor to execute the GNSS-IR multi-station fusion water level monitoring method according to any one of claims 1 to 4.

7. An electronic device, characterized in that, Include a processor and a memory, the processor is electrically connected to the memory, the memory is used to store instructions and data, and the processor is used to execute the steps in the GNSS-IR multi-station fusion water level monitoring method according to any one of claims 1 to 4.

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