Railway signal enhancer ad hoc network management method and system based on beidou fusion positioning

Abstract

The present application relates to the technical field of railway signal enhancement, and discloses a railway signal enhancer ad hoc network management method and system based on Beidou integrated positioning, which comprises the following steps: receiving Beidou satellite signals by a signal enhancer, solving the initial coordinates of the signal enhancer, monitoring communication signals from a ground control base station by the signal enhancer, triggering a differential relay mode when the communication signal level is lower than a first preset threshold or the data packet loss rate is higher than a second preset threshold, selecting one from a plurality of signal enhancers as a temporary master reference, the selection is carried out by a weighted least squares algorithm with the differential quality factor of each device as the input weight, receiving the differential correction data sent by the temporary master reference by the signal enhancer which is not selected as the temporary master reference, and correcting the initial coordinates of the signal enhancer by using the data, thereby realizing the intelligence, reliability and stability of system operation and maintenance in complex railway environment.

Description

Technical Field

[0001] This invention relates to the technical field of railway signal enhancement, and discloses a self-organizing network management method and system for railway signal enhancers based on BeiDou fusion positioning. Background Technology

[0002] Railway signal boosters are key equipment for ensuring railway communication signal coverage. Traditional equipment has many shortcomings, such as: lack of autonomous positioning and reporting capabilities, requiring maintenance personnel to troubleshoot point by point along the railway line after a failure, which is inefficient and costly; in mountainous areas, tunnels, and other areas where mobile public networks are lacking, the communication link between the equipment and the remote maintenance platform is interrupted, making status monitoring impossible; traditional GNSS reference stations are costly to build and cannot be deployed in a mobile manner, resulting in a lack of effective differential positioning coverage in long railway sections and limiting the positioning accuracy of the equipment. Summary of the Invention

[0003] To address the aforementioned technical problems, the main objective of this invention is to provide a method and system for managing the self-organizing network of railway signal boosters based on BeiDou fusion positioning. The method for managing the self-organizing network of railway signal boosters based on BeiDou fusion positioning includes:

[0004] The signal booster receives BeiDou satellite signals and calculates its own initial coordinates.

[0005] The signal booster monitors communication signals from the ground control base station. When the communication signal level is lower than a first preset threshold or the data packet loss rate is higher than a second preset threshold, it triggers the differential relay mode.

[0006] In the differential relay mode, the multiple signal enhancers exchange their respective differential quality factors through an ad hoc network link;

[0007] Based on the differential quality factor, one of the multiple signal enhancers is selected as a temporary master reference. The selection is carried out by a weighted least squares algorithm with the differential quality factor of each device as the input weight.

[0008] The signal enhancer that was not elected as the temporary master reference receives the differential correction data sent by the temporary master reference and uses the data to correct its own initial coordinates.

[0009] Each signal booster sends the corrected coordinates and equipment operating status data to the remote operation and maintenance platform via the BeiDou short message function.

[0010] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0011] The method by which the signal enhancer receives BeiDou satellite signals and calculates its own initial coordinates includes:

[0012] The signal enhancer receives satellite signals from the BeiDou-3 satellite navigation system via the BeiDou positioning module;

[0013] The satellite signal is processed in real time using a single-point positioning mode, and the initial coordinates of the satellite itself, including longitude, latitude and elevation, are output.

[0014] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0015] The signal booster acquires the radio frequency signal level and data packet loss rate of the communication link with the ground control base station in real time through a preset signal detection module. The condition for triggering the differential relay mode is that when the radio frequency signal level is lower than the first preset threshold, it indicates that the wireless channel quality has deteriorated; when the data packet loss rate is higher than the second preset threshold, it indicates that the network connectivity has decreased.

[0016] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0017] When the quality of the direct communication link between the signal booster and the ground control base station deteriorates, a cooperative working mode is triggered by a single signal booster and constructed between multiple adjacent signal boosters through self-organizing network links.

[0018] In differential relay mode, each signal enhancer interacts to locate differential data through the ad hoc network link, and generates a temporary master reference through dynamic election. The temporary master reference is then used to provide differential correction data to other slave devices in the network.

[0019] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0020] The signal enhancer periodically exchanges data packets within the self-organizing network link in a multi-hop broadcast manner through its self-organizing network communication module. The data packets contain at least its own original pseudorange observation, carrier phase observation, and differential quality factor.

[0021] During the dynamic election process, each signal enhancer aggregates the differential quality factors of all neighboring devices through the self-organizing network link;

[0022] Each signal enhancer independently runs a weighted least squares algorithm, using the differential quality factor as input weights, to evaluate the suitability of each device as a potential benchmark.

[0023] The algorithm takes maximizing the overall cooperative positioning accuracy of the network after differential correction as the objective function, and solves iteratively through a distributed consensus mechanism to finally elect a unique temporary master reference.

[0024] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0025] The differential quality factor is a comprehensive evaluation value, which is obtained by the main control unit of the signal enhancer based on the real-time output of its Beidou positioning module. The calculation parameters include the signal-to-noise ratio weighted average of the satellite signal, the phase noise variance of the carrier phase-locked loop, and the geometric distribution accuracy factor of the currently visible satellites.

[0026] The interactive differential quality factor is encapsulated and broadcast as a necessary field of the data packet in the self-organizing network link, and a digital signature is attached.

[0027] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0028] The process of selecting the signal enhancers that were not elected as the temporary master reference is dynamic and distributed:

[0029] After the weighted least squares algorithm completes the election, the temporary master reference broadcasts a reference announcement message, including a unique device identifier, through the ad hoc network link.

[0030] Upon receiving the baseline announcement message and finding that its own identifier does not match the announcement identifier, the signal amplifier configures itself as a slave device and initiates a listening session for receiving differential correction data.

[0031] If any signal booster does not receive the reference announcement message within a preset time, it is determined that a partition has occurred in the current network, and the election process of the temporary primary reference is retried within the network partition in which it is located.

[0032] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0033] The method for correcting its initial coordinates using the differential correction data includes:

[0034] The slave device receives the differential correction data sent by the temporary master reference;

[0035] The master control unit of the slave device performs real-time dynamic differential positioning calculation of the carrier phase using its own original pseudorange observations and carrier phase observations, along with the received differential correction data.

[0036] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0037] The method for sending the corrected coordinates and equipment operating status data via the BeiDou short message function includes:

[0038] The main control unit of the signal amplifier encapsulates and prioritizes the data to be transmitted.

[0039] Equipment fault alarm information and abnormal coordinate data are marked as high priority, while routine status monitoring data are marked as low priority;

[0040] The BeiDou short message service dynamically allocates communication resources based on data priority, prioritizing the transmission of high-priority data.

[0041] After receiving the data, the remote operation and maintenance platform parses out the corrected coordinates and equipment operating status data according to the embedded protocol.

[0042] As a preferred embodiment of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning of the present invention, wherein:

[0043] The positioning module includes a signal receiving unit and a coordinate calculation unit;

[0044] The signal detection module includes a level acquisition unit and a packet loss rate statistics unit;

[0045] The mode control module includes a threshold comparison unit and a mode triggering unit, wherein the threshold comparison unit compares the acquired signal level with a first preset threshold and the packet loss rate with a second preset threshold, and the mode triggering unit triggers the differential relay mode when any condition is met;

[0046] The ad hoc network communication module includes a data encapsulation unit and a multi-hop transmission unit. The data encapsulation unit encapsulates the original observations and differential quality factors into data packets, and the multi-hop transmission unit transmits data in the ad hoc network link in a multi-hop broadcast manner through a protocol.

[0047] The benchmark election module includes a factor aggregation unit and an algorithm calculation unit. The factor aggregation unit collects the differential quality factors of neighboring devices, and the algorithm calculation unit elects a temporary master benchmark by using the differential quality factors as input weights through a weighted least squares algorithm.

[0048] The differential correction module includes a data receiving unit and an RTK calculation unit; the data return module includes a priority scheduling unit and a short message communication unit; and the main control module includes a process control unit and a collaborative management unit.

[0049] The beneficial effects of this invention are:

[0050] This application achieves autonomous positioning through the BeiDou module and, combined with the BeiDou short message function, directly transmits the device location and status back to the operation and maintenance platform in an environment without a public network. This solves the problem of relying on manual troubleshooting for fault location and greatly improves operation and maintenance efficiency.

[0051] This application automatically triggers differential relay mode by monitoring the communication quality with ground base stations, and dynamically elects a temporary master reference based on the differential quality factor. It then distributes differential correction data using self-organizing network links, enabling the formation of a dynamic differential network with centimeter-level accuracy along railway lines in areas without traditional reference station coverage, thus solving the problem of insufficient differential coverage.

[0052] The system formed by this invention does not rely on a fixed central node. When local equipment fails or the network topology changes, the system can automatically reorganize and re-elect the reference through self-organizing network links, continuously providing positioning enhancement and status feedback services, thus ensuring the intelligence, reliability and stability of system operation and maintenance in complex railway environments. Attached Figure Description

[0053] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0054] Figure 1 This is a flowchart of the self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to the present invention;

[0055] Figure 2 This is a diagram illustrating the composition of the self-organizing network management system for railway signal boosters based on BeiDou fusion positioning, as described in this invention.

[0056] Figure 3 This is a schematic diagram of the main station playing the main reference in the self-organizing network management method of railway signal enhancer based on Beidou fusion positioning of the present invention. Detailed Implementation

[0057] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0058] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0059] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0060] Example 1

[0061] like Figure 1 As shown, the self-organizing network management method for railway signal boosters based on BeiDou fusion positioning includes:

[0062] The signal booster receives BeiDou satellite signals and calculates its own initial coordinates.

[0063] The method by which the signal enhancer receives BeiDou satellite signals and calculates its own initial coordinates includes:

[0064] The signal enhancer receives satellite signals from the BeiDou-3 satellite navigation system via the BeiDou positioning module;

[0065] The satellite signal is processed in real time using a single-point positioning mode, and the initial coordinates of the satellite itself, including longitude, latitude and elevation, are output.

[0066] In this application, a preferred method for real-time calculation using a single-point positioning mode includes the following specific implementation:

[0067] The signal enhancer receives downlink navigation signals from the BeiDou satellite navigation system through its built-in BeiDou positioning module. It first performs downconversion and demodulation on the received radio frequency signals, and then parses the navigation message from the signal structure. The navigation message contains key parameters for positioning calculation, including the satellite's precise orbital parameters and system time information.

[0068] The BeiDou positioning module compares the pseudo-random code generated inside the receiver with the received satellite pseudo-random code to measure the signal transmission time delay. It then multiplies the time delay by the speed of light to calculate the pseudorange observation value between the satellite and the signal enhancer. In a preferred example, the pseudorange observation value can be a comprehensive distance observation value that includes multiple error sources such as receiver clock error, satellite clock error, ionospheric delay, and tropospheric delay.

[0069] The BeiDou positioning module uses the orbital parameters of multiple satellites and the corresponding pseudorange observations to construct a set of positioning equations. The positioning module includes a position calculation engine to solve the set of positioning equations.

[0070] In this application, a preferred method for implementing the positioning solution equation includes:

[0071] The railway signal booster based on BeiDou fusion positioning receives signals from the BeiDou satellite navigation system and autonomously calculates its spatial position.

[0072] The positioning process involves spatial intersection via trilateration. The signal enhancer calculates pseudorange observations, including various error sources, by measuring the radio signal-guided propagation delay between the receiver and multiple in-orbit BeiDou satellites. Each satellite provides a pseudorange observation equation. By simultaneously solving multiple equations, the receiver's spatial coordinates in a specific coordinate system and the receiver clock error are calculated.

[0073] Furthermore, the observation equation is established. For the i-th visible BeiDou satellite, the pseudorange observation equation is expressed as follows:

[0074] Pseudorange observation = Geometric distance between satellite and receiver + Distance deviation caused by receiver clock error + Propagation path error + Observation noise

[0075] Wherein: the geometric distance between the satellite and the receiver is determined by the instantaneous spatial coordinates of the satellite and the spatial coordinates of the receiver to be determined.

[0076] Instantaneous spatial coordinates are obtained by decoding ephemeris parameters in the navigation message;

[0077] Distance deviation caused by receiver clock bias: Due to the discrepancy between the receiver's local clock and the BeiDou system time, the product of the discrepancy and the speed of light constitutes a common distance error term.

[0078] Propagation path error includes errors caused by the influence of the medium on the signal during propagation, such as ionospheric delay and tropospheric delay.

[0079] Observation noise includes random errors such as multipath effects and receiver internal thermal noise.

[0080] Furthermore, by simultaneously observing four or more BeiDou satellites, the four unknown parameters of the receiver's three-dimensional spatial coordinates (X, Y, Z) and receiver clock error are solved, thus constructing an overdetermined system of equations consisting of four or more pseudorange observation equations.

[0081] Specifically, the overdetermined equation system consists of nonlinear equations. In a practical implementation, the position calculation method built into the signal enhancer includes:

[0082] Using the receiver's approximate coordinates, such as the previous positioning result or a rough location, the nonlinear observation equation is expanded at this approximate point using Taylor's formula, retaining the first-order terms, thus transforming the nonlinear problem into a linear problem.

[0083] Furthermore, the difference between the pseudorange observations and the calculated values ​​based on approximate coordinates is used as the observation residual to construct a linearized set of error equations.

[0084] Furthermore, the linear equations are solved using the least squares estimation algorithm to obtain the optimal estimates of the receiver coordinate correction and clock error correction.

[0085] The approximate coordinates are updated by solving for the new coordinates. The linearization and solving process is repeated and iterative calculations are performed until the coordinate correction is less than the preset convergence threshold. Finally, high-precision receiver initial coordinates, including longitude, latitude and elevation, are output.

[0086] Specifically, the solution process involves iterative calculations to find the optimal three-dimensional spatial coordinates and receiver clock error, minimizing the difference between the calculated distance from the point to all observed satellites and the measured pseudorange. The initial coordinates of the signal enhancer are then output, expressed in a geodetic coordinate system, including longitude, latitude, and elevation.

[0087] The signal booster monitors communication signals from the ground control base station. When the communication signal level is lower than a first preset threshold or the data packet loss rate is higher than a second preset threshold, it triggers the differential relay mode.

[0088] The signal booster acquires the radio frequency signal level and data packet loss rate of the communication link with the ground control base station in real time through a preset signal detection module. The condition for triggering the differential relay mode is that when the radio frequency signal level is lower than the first preset threshold, it indicates that the wireless channel quality has deteriorated; when the data packet loss rate is higher than the second preset threshold, it indicates that the network connectivity has decreased.

[0089] Specifically, the implementation method of the signal booster monitoring communication signals from the ground control base station and triggering differential relay mode when the signal level or packet loss rate does not meet the conditions includes:

[0090] The signal booster monitors the quality of the communication link with the ground control base station through its built-in signal detection module.

[0091] The module measures the power of the receiving channel to obtain the strength of the downlink radio frequency signal from the ground control base station in real time, and the strength value is the communication signal level.

[0092] The module counts specific protocol data packets sent to or received from the ground control base station at the application layer, and calculates the proportion of data packets that do not receive a valid response within a pre-set time window to calculate the packet loss rate of the data packets in real time.

[0093] The signal detection module compares the real-time acquired radio frequency signal level with a first preset threshold preset within the device; simultaneously, it compares the real-time statistical data packet loss rate with a second preset threshold preset within the device. These two thresholds are preset based on the minimum link quality requirements necessary to maintain stable communication with the ground control base station.

[0094] Furthermore, a preferred trigger is an automatic logical decision-making process based on the comparison results:

[0095] When the real-time acquired radio frequency signal level is lower than the first preset threshold, it is determined that the wireless channel quality has deteriorated and the physical layer connection is unreliable.

[0096] When the real-time data packet loss rate exceeds the second preset threshold, it is determined that the network connectivity has deteriorated and the data transmission link is unreliable.

[0097] If any of the above conditions are met, the main control unit of the signal booster will automatically trigger the differential relay mode.

[0098] When the quality of the direct communication link between the signal booster and the ground control base station deteriorates, a cooperative working mode is triggered by a single signal booster and constructed between multiple adjacent signal boosters through self-organizing network links.

[0099] In differential relay mode, each signal enhancer interacts to locate differential data through the ad hoc network link, and generates a temporary master reference through dynamic election. The temporary master reference is then used to provide differential correction data to other slave devices in the network.

[0100] When any signal booster triggers this mode due to deterioration in the quality of its direct communication link with the ground control base station, that device acts as the initiating node. Through its built-in ad hoc network communication module, it periodically broadcasts a mode activation signal containing a specific identifier on a pre-configured communication frequency band. Neighboring signal boosters receiving this signal analyze its content, recognize the need to enter a cooperative working state, activate their own ad hoc network communication modules, and establish point-to-point communication links with the initiating node and with each other. Through this diffusion of adjacency, a distributed ad hoc network link is eventually autonomously constructed among multiple adjacent signal boosters, forming a temporary device cooperative network.

[0101] After the self-organizing network link is successfully established, it enters a stable operation phase. Each signal enhancer in the network periodically broadcasts or exchanges its own positioning differential data on demand through the self-organizing network link. A preferred positioning differential data includes at least the raw observation data obtained by the BeiDou positioning module, such as pseudorange, carrier phase, and differential quality factor used to evaluate its data quality.

[0102] In a preferred embodiment, the differential quality factor Q is calculated as follows:

[0103] ;

[0104] SNR represents the signal-to-noise ratio weighted average of all currently visible BeiDou satellite signals;

[0105] The phase noise variance of the carrier phase-locked loop represents the stability of the carrier phase observations.

[0106] DOP represents the geometric distribution accuracy factor of currently visible satellites, such as geometric accuracy factor or position accuracy factor;

[0107] , The sum is a preset normalized weighting coefficient used to balance the influence of parameters of different dimensions and orders of magnitude on the comprehensive evaluation value.

[0108] The higher the value of the differential quality factor Q, the better the quality of the positioning observation data of the device, and the more suitable it is to be selected as the temporary master benchmark.

[0109] Specifically, each device aggregates its own and all neighboring devices' differential quality factors, then normalizes the differential quality factors of each candidate device as its input weight.

[0110] In the differential relay mode, the differential quality factor is selected from multiple signal enhancers as a temporary master reference. This selection is performed using a weighted least squares algorithm with the differential quality factors of each device as input weights. Specifically:

[0111] Each signal booster collects the differential quality factors broadcast by all neighboring devices via an ad hoc network link, normalizes these differential quality factors, and converts them into election weights that characterize the reliability of each device's data. Specifically, the higher a device's differential quality factor value, the greater its assigned election weight, and the stronger its influence in the election process.

[0112] Each signal booster independently evaluates the fit of each candidate device in the network as a potential temporary master benchmark.

[0113] The evaluation is conducted using a pre-defined objective function, which simulates the estimated level of overall cooperative positioning accuracy that the entire ad hoc network can achieve after applying its differential correction data when a candidate device serves as a temporary master reference.

[0114] During the evaluation process, the objective function calculation not only focuses on the differential quality of the candidate device itself, but also evaluates how the candidate device can improve the positioning accuracy of other high-weight devices in the network.

[0115] A candidate device will have a higher objective function evaluation value if it enables more high-weight subordinate devices to achieve higher predicted positioning accuracy.

[0116] Each signal enhancer independently calculates the objective function evaluation value of all candidate devices, and by comparison, the candidate device with the highest evaluation value is elected as the unique temporary master benchmark.

[0117] By using a weighted least squares algorithm election mechanism, the device that maximizes the performance of the entire network's collaborative positioning is intelligently selected as the temporary primary reference, ensuring that the elected leader node can most effectively serve the network as a whole, and achieving intelligent, reliable and stable system operation and maintenance in complex railway environments.

[0118] It should be noted that in this application, in a preferred embodiment, all devices run a preset election algorithm based on the received neighbor device data. The election algorithm uses the differential quality factor reported by each device as the core input parameter. Through comparison and calculation, for example, it identifies and unanimously agrees to elect a temporary master reference device with the best differential quality factor. This process is distributed and does not depend on any external control node.

[0119] Furthermore, after the election, the temporary primary reference device assumes the function of a reference station. It calculates the differential correction amount applicable to the local network environment using its own high-quality positioning data, and continuously or periodically broadcasts this differential correction data to other devices in the network through the self-organizing network link.

[0120] In the differential relay mode, the multiple signal enhancers exchange their respective differential quality factors through an ad hoc network link;

[0121] Based on the differential quality factor, one of the multiple signal enhancers is selected as a temporary master reference. The selection is carried out by a weighted least squares algorithm with the differential quality factor of each device as the input weight.

[0122] When the quality of the direct communication link between the signal booster and the ground control base station deteriorates, a cooperative working mode is triggered by a single signal booster and constructed between multiple adjacent signal boosters through self-organizing network links.

[0123] The election of a temporary master benchmark based on the weighted least squares algorithm is a distributed, algorithmic consensus-based process.

[0124] Each signal booster continuously monitors the ad hoc network link, collecting broadcast packets from all communicable neighboring devices. From these packets, the differential quality factor of each neighboring device is extracted.

[0125] like Figure 3 As shown, each device independently runs a weighted least squares algorithm to complete the election. In the least squares algorithm model, all neighboring devices in the network are considered as potential baseline candidates.

[0126] A specific implementation method of the preferred least squares algorithm includes directly using the differential quality factor of each candidate device as the input weight of that candidate device in the algorithm. This means that the higher the differential quality factor of a device, the greater its weight in the election algorithm, reflecting that its data is more reliable.

[0127] Furthermore, the objective function of the weighted least squares algorithm is set to maximize the estimated positioning accuracy factor of the network as a whole after differential correction. The positioning accuracy factor is an index that can predict the positioning solution accuracy based on satellite geometric distribution and observation quality.

[0128] The algorithm searches for a candidate device that maximizes the objective function value through iterative calculation. Since all devices use the same algorithm and input data in the same network, the algorithm iteratively solves the problem and consistently elects the same device as the unique temporary master benchmark.

[0129] In differential relay mode, each signal enhancer interacts to locate differential data through the ad hoc network link, and generates a temporary master reference through dynamic election. The temporary master reference is then used to provide differential correction data to other slave devices in the network.

[0130] The signal enhancer periodically exchanges data packets within the self-organizing network link in a multi-hop broadcast manner through its self-organizing network communication module. The data packets contain at least its own original pseudorange observation, carrier phase observation, and differential quality factor.

[0131] The dynamic election is based on the received neighbor device data packets: each signal enhancer uses the differential quality factors of all communicable neighbor devices in the network as input weights for a weighted least squares algorithm to calculate the weight value of each device as a potential benchmark.

[0132] The algorithm takes maximizing the prediction accuracy factor of the overall network's differentially corrected position as the objective function, iteratively solves for and elects the unique temporary master reference.

[0133] In a preferred embodiment, each signal enhancer in the ad hoc network data exchange mechanism transmits data packets within the ad hoc network link via its built-in ad hoc network communication module, according to a preset communication period, using a multi-hop broadcast method. The data packets are encapsulated using a specific network protocol frame format, and their payload data includes at least:

[0134] The device's own raw pseudorange and carrier phase observations are the raw observation data necessary for high-precision differential positioning calculations.

[0135] The device's differential quality factor is a comprehensive evaluation value used to quantify the reliability and accuracy of its current positioning data.

[0136] Through this periodic, multi-hop forwarding packet exchange, each device in the network can obtain the aforementioned key data from all neighboring devices within its communication range, laying the information foundation for subsequent collaborative computing.

[0137] The differential quality factor is a comprehensive evaluation value, which is obtained by the main control unit of the signal enhancer based on the real-time output of its Beidou positioning module. The calculation parameters include the signal-to-noise ratio weighted average of the satellite signal, the phase noise variance of the carrier phase-locked loop, and the geometric distribution accuracy factor of the currently visible satellites.

[0138] The interactive differential quality factor is encapsulated and broadcast as a necessary field of the data packet in the self-organizing network link, and a digital signature is attached.

[0139] The signal enhancer that was not elected as the temporary master reference receives the differential correction data sent by the temporary master reference and uses the data to correct its own initial coordinates.

[0140] Each signal booster sends the corrected coordinates and equipment operating status data to the remote operation and maintenance platform via the BeiDou short message function.

[0141] Specifically, the method for correcting its initial coordinates using the differential correction data includes:

[0142] The slave device receives differential correction data from the temporary master datum, the differential correction data including the coordinate observation correction amount of the temporary master datum and its covariance matrix, etc.

[0143] In a preferred example, the coordinate observation correction is a systematic error correction value calculated by comparing the temporary master reference device's high-precision BeiDou positioning observation data with the precise coordinates calculated through long-term observation.

[0144] Error correction values ​​are used to represent the specific numerical representation of common or quasi-common errors in satellite navigation observations at the temporary master reference, including: three-dimensional coordinate correction vectors and clock error corrections, etc.

[0145] Specifically, the three-dimensional coordinate correction vector includes correction components for the north, east, and elevation directions. This vector is directly used to compensate for observation errors of subordinate equipment in the corresponding directions.

[0146] Among them, the north, east, and elevation directions can also be represented in the X, Y, Z geocentric coordinate system.

[0147] The clock bias correction is the deviation correction value of the temporary primary reference receiver clock bias relative to the BeiDou system time. It is used to correct the local clock bias of the slave equipment, and the local clock bias affects the pseudorange observation of all satellites.

[0148] The coordinate observation correction is used to transmit common domain errors, such as satellite ephemeris errors, satellite clock errors, and most of the ionospheric and tropospheric delay errors, accurately measured at the temporary master reference to the slave devices in the network.

[0149] Slave devices effectively eliminate the effects of spatial correlation errors in their local solutions by applying corrections.

[0150] Furthermore, the covariance matrix is ​​a mathematical matrix associated with the coordinate observation correction, used to quantify the uncertainty of the correction and the correlation of errors between components.

[0151] The covariance matrix is ​​a symmetric square matrix, and its dimension corresponds to the dimension of the coordinate correction. For example, for three-dimensional coordinates and clock error, it is a 4x4 matrix.

[0152] The diagonal elements of the covariance matrix represent the variance of coordinate observation corrections in each component, such as north, east, altitude, and clock error. The smaller the variance of the covariance matrix, the more reliable the correction in that direction.

[0153] The off-diagonal elements of the covariance matrix represent the covariance between different correction components, reflecting the degree of correlation between component errors. For example, the correction error in the elevation direction may be correlated with the clock error correction error.

[0154] When slave devices execute data fusion algorithms such as weighted least squares or Kalman filtering, the inverse of the covariance matrix is ​​used as the weight matrix for the correction.

[0155] Furthermore, correction components with smaller variances are given higher weights in the solution.

[0156] By using off-diagonal elements, the solution model more accurately describes the propagation characteristics of errors, avoiding the decrease or even divergence in solution accuracy caused by ignoring error correlation, and improving the success rate of fixing integer ambiguity in real-time dynamic differential positioning of carrier phase and the reliability of the final positioning result.

[0157] In practice, the coordinate observation correction and its covariance matrix are calculated and encapsulated by the master control unit of the temporary master reference, and broadcast to the slave devices in the network through the self-organizing network communication module at a preset period or in an event-triggered manner.

[0158] By explicitly defining that the differential correction data must at least include the coordinate observation correction amount and its covariance matrix, this technical solution ensures that when the slave device receives and uses this data for local coordinate correction, it can obtain a benchmark for error correction, evaluate the reliability of this benchmark, and perform optimal fusion. This improves the accuracy of collaborative positioning of all signal enhancers within the ad hoc network in complex railway environments.

[0159] The master control unit of the slave device performs real-time dynamic differential positioning calculation of the carrier phase using its own original pseudorange observations and carrier phase observations, along with the received differential correction data.

[0160] Signal enhancers that are not elected as the temporary master reference, acting as slave devices, continuously receive differential correction data streams broadcast by the temporary master reference device via the ad hoc network communication module. After being parsed by the communication protocol, the differential correction data stream contains the following core information:

[0161] The coordinate observation correction reflects the systematic error correction value calculated by the temporary master reference equipment using high-quality observation data;

[0162] The covariance matrix characterizes the accuracy of coordinate observation corrections and the error correlation between different observations.

[0163] The master control unit of the slave device fuses the received differential correction data with the raw pseudorange and carrier phase observations output in real time from its own BeiDou positioning module, and performs real-time dynamic differential positioning calculation based on the carrier phase. The calculation process effectively eliminates common errors such as satellite orbital errors, satellite clock errors, ionospheric delays, and tropospheric delays, based on the spatial correlation between the temporary master reference and the slave device. The master control unit utilizes the high precision of the carrier phase observations, employing cycle slip detection and repair, integer ambiguity determination processing steps, and constraining the observation equations with differential correction, ultimately outputting centimeter-level accurate device coordinates after differential correction.

[0164] The method for sending the corrected coordinates and equipment operating status data via the BeiDou short message function includes:

[0165] The main control unit of the signal amplifier encapsulates and prioritizes the data to be transmitted.

[0166] Equipment fault alarm information and abnormal coordinate data are marked as high priority, while routine status monitoring data are marked as low priority;

[0167] The BeiDou short message service dynamically allocates communication resources based on data priority, prioritizing the transmission of high-priority data.

[0168] After receiving the data, the remote operation and maintenance platform parses out the corrected coordinates and equipment operating status data according to the embedded protocol.

[0169] The main control unit of the signal booster organizes and encapsulates the corrected coordinates and equipment operating status data. The data encapsulation follows a specific application layer protocol format, packaging the corrected coordinates, equipment operating status parameters, and equipment identification information into transmission frames that meet the requirements of BeiDou short message communication.

[0170] During the encapsulation process, the main control unit executes a priority scheduling mechanism:

[0171] Equipment fault alarm information and abnormal coordinate data are marked as high priority;

[0172] Routine condition monitoring data is marked as low priority.

[0173] BeiDou short message service dynamically manages communication resources based on data priority:

[0174] Prioritize allocating communication time slots and power resources to high-priority data;

[0175] When communication resources are scarce, the transmission of low-priority data should be temporarily suspended to ensure the timely transmission of high-priority data.

[0176] After receiving the BeiDou short message, the remote operation and maintenance platform parses the data frame according to the preset communication protocol, extracts the device identifier, corrected coordinates and operating status information, and realizes remote monitoring and operation and maintenance management of the device.

[0177] Differential correction processing improves equipment positioning accuracy, while intelligent priority scheduling ensures reliable transmission of key monitoring data in low-bandwidth BeiDou short message channels, enabling high-precision positioning and reliable status monitoring of equipment in railway lines without public network coverage.

[0178] Example 2

[0179] like Figure 2 As shown, the railway signal booster self-organizing network management system based on BeiDou fusion positioning includes:

[0180] The positioning module includes a signal receiving unit and a coordinate calculation unit. The signal receiving unit is used to receive BeiDou satellite signals, and the coordinate calculation unit performs real-time calculation of the satellite signals through a single-point positioning mode and outputs its own initial coordinates.

[0181] The signal detection module includes a level acquisition unit and a packet loss rate statistics unit, wherein the level acquisition unit acquires the radio frequency signal level from the ground control base station in real time, and the packet loss rate statistics unit calculates the packet loss rate of the data packets.

[0182] The mode control module includes a threshold comparison unit and a mode triggering unit, wherein the threshold comparison unit compares the acquired signal level with a first preset threshold and the packet loss rate with a second preset threshold, and the mode triggering unit triggers the differential relay mode when any condition is met;

[0183] The ad hoc network communication module includes a data encapsulation unit and a multi-hop transmission unit. The data encapsulation unit encapsulates the original observations and differential quality factors into data packets, and the multi-hop transmission unit transmits data in the ad hoc network link in a multi-hop broadcast manner using the IEEE 802.15.4g protocol.

[0184] The benchmark election module includes a factor aggregation unit and an algorithm calculation unit. The factor aggregation unit collects the differential quality factors of neighboring devices, and the algorithm calculation unit elects a temporary master benchmark by using the differential quality factors as input weights through a weighted least squares algorithm.

[0185] The differential correction module includes a data receiving unit and an RTK calculation unit. The data receiving unit receives differential correction data sent by a temporary master reference, and the RTK calculation unit performs real-time dynamic differential positioning calculation based on carrier phase observations and outputs corrected coordinates with centimeter-level accuracy.

[0186] The data feedback module includes a priority scheduling unit and a short message communication unit. The priority scheduling unit marks fault alarms and coordinate anomaly data as high priority, and the short message communication unit sends data to the remote operation and maintenance platform through the Beidou BD-2 short message protocol.

[0187] The main control module includes a process control unit and a collaborative management unit, wherein the process control unit coordinates the working sequence of each module, and the collaborative management unit handles device role configuration and network status maintenance.

[0188] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only two embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, variations in the size, dimensions, structure, shape, and proportions of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc. For instance, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of the invention. The order or sequence of any process or method steps may be changed or rearranged according to alternative embodiments. Any "device plus function" clause is intended to cover the structure performing the function described herein, and not only structurally equivalent but also equivalent in structure. Other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments without departing from the scope of the invention. Therefore, the present invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0189] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the currently considered best mode for carrying out the invention, or those features that are not relevant to implementing the invention) may be omitted.

[0190] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those of ordinary skill in the art who benefit from this disclosure, the development effort will be a routine task in design, manufacturing, and production without requiring extensive experimentation.

[0191] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A self-organizing network management method for railway signal boosters based on BeiDou fusion positioning, characterized in that, include: The signal booster receives BeiDou satellite signals and calculates its own initial coordinates. The signal booster monitors communication signals from the ground control base station. When the communication signal level is lower than a first preset threshold or the data packet loss rate is higher than a second preset threshold, it triggers the differential relay mode. In the differential relay mode, the multiple signal enhancers exchange their respective differential quality factors through an ad hoc network link; Based on the differential quality factor, one of the multiple signal enhancers is selected as a temporary master reference. The selection is carried out by a weighted least squares algorithm with the differential quality factor of each device as the input weight. The signal enhancer that was not elected as the temporary master reference receives the differential correction data sent by the temporary master reference and uses the data to correct its own initial coordinates. Each signal booster sends the corrected coordinates and equipment operating status data to the remote operation and maintenance platform via the BeiDou short message function.

2. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 1, characterized in that: The method by which the signal enhancer receives BeiDou satellite signals and calculates its own initial coordinates includes: The signal enhancer receives satellite signals from the BeiDou Navigation Satellite System via the BeiDou positioning module; The satellite signal is processed in real time using a single-point positioning mode, and the initial coordinates of the satellite itself, including longitude, latitude and elevation, are output.

3. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 1, characterized in that: The signal booster uses a preset signal detection module to acquire in real time the radio frequency signal level of the communication link with the ground control base station and the packet loss rate of data packets. The conditions for triggering the differential relay mode are as follows: when the radio frequency signal level is lower than the first preset threshold, it indicates a deterioration in the wireless channel quality; when the data packet loss rate is higher than the second preset threshold, it indicates a decrease in network connectivity.

4. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 3, characterized in that: When the quality of the direct communication link between the signal booster and the ground control base station deteriorates, a cooperative working mode is triggered by a single signal booster and constructed between multiple adjacent signal boosters through self-organizing network links. In differential relay mode, each signal enhancer interacts to locate differential data through the ad hoc network link, and generates a temporary master reference through dynamic election. The temporary master reference is then used to provide differential correction data to other slave devices in the network.

5. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 4, characterized in that: The signal enhancer periodically exchanges data packets within the self-organizing network link in a multi-hop broadcast manner through its self-organizing network communication module. The data packets contain its own raw pseudorange observations, carrier phase observations, and differential quality factors. During the dynamic election process, each signal enhancer aggregates the differential quality factors of all neighboring devices through the self-organizing network link; Each signal enhancer independently runs a weighted least squares algorithm, using the differential quality factor as input weights, to evaluate the suitability of each device as a potential benchmark. The algorithm takes maximizing the overall cooperative positioning accuracy of the network after differential correction as the objective function, and solves iteratively through a distributed consensus mechanism to finally elect a unique temporary master reference.

6. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 1, characterized in that: The differential quality factor is a comprehensive evaluation value, which is obtained by the main control unit of the signal enhancer based on the real-time output of its Beidou positioning module. The calculation parameters include the signal-to-noise ratio weighted average of the satellite signal, the phase noise variance of the carrier phase-locked loop, and the geometric distribution accuracy factor of the currently visible satellites. The interactive differential quality factor is encapsulated and broadcast as a necessary field of the data packet in the self-organizing network link, and a digital signature is attached.

7. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 6, characterized in that: The process of selecting the signal enhancers that were not elected as the temporary master reference is dynamic and distributed: After the weighted least squares algorithm completes the election, the temporary master reference broadcasts a reference announcement message, including a unique device identifier, through the ad hoc network link. Upon receiving the baseline announcement message and finding that its own identifier does not match the announcement identifier, the signal amplifier configures itself as a slave device and initiates a listening session for receiving differential correction data. If any signal booster does not receive the reference announcement message within a preset time, it is determined that a partition has occurred in the current network, and the election process of the temporary primary reference is retried within the network partition in which it is located.

8. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 1, characterized in that: The method for correcting its initial coordinates using the differential correction data includes: The slave device receives the differential correction data sent by the temporary master reference; The master control unit of the slave device performs real-time dynamic differential positioning calculation of the carrier phase using its own original pseudorange observations and carrier phase observations, along with the received differential correction data.

9. The self-organizing network management method for railway signal enhancers based on BeiDou fusion positioning according to claim 8, characterized in that: The method for sending the corrected coordinates and equipment operating status data via the BeiDou short message function includes: The main control unit of the signal amplifier encapsulates and prioritizes the data to be transmitted. Equipment fault alarm information and abnormal coordinate data are marked as high priority, while routine status monitoring data are marked as low priority; The BeiDou short message service dynamically allocates communication resources based on data priority, prioritizing the transmission of high-priority data. After receiving the data, the remote operation and maintenance platform parses out the corrected coordinates and equipment operating status data according to the embedded protocol.

10. A railway signal booster self-organizing network management system based on BeiDou fusion positioning, used to implement the railway signal booster self-organizing network management method based on BeiDou fusion positioning as described in any one of claims 1-9, characterized in that, include: The positioning module includes a signal receiving unit and a coordinate calculation unit; The signal detection module includes a level acquisition unit and a packet loss rate statistics unit; The mode control module includes a threshold comparison unit and a mode triggering unit, wherein the threshold comparison unit compares the acquired signal level with a first preset threshold and the packet loss rate with a second preset threshold, and the mode triggering unit triggers the differential relay mode when any condition is met; The ad hoc network communication module includes a data encapsulation unit and a multi-hop transmission unit. The data encapsulation unit encapsulates the original observations and differential quality factors into data packets, and the multi-hop transmission unit transmits data in the ad hoc network link in a multi-hop broadcast manner through a protocol. The benchmark election module includes a factor aggregation unit and an algorithm calculation unit. The factor aggregation unit collects the differential quality factors of neighboring devices, and the algorithm calculation unit elects a temporary master benchmark by using the differential quality factors as input weights through a weighted least squares algorithm. The differential correction module includes a data receiving unit and an RTK calculation unit; The data feedback module includes a priority scheduling unit and a short message communication unit; the main control module includes a process control unit and a collaborative management unit.

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