Method, device and system for positioning and monitoring train

Abstract

The embodiment of the invention provides a method, device and system for positioning and monitoring a train, electronic equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: in response to a received space-time parameter set sent by at least three positioning base stations, determining the one-way transmission time of an ultra-wideband signal between each positioning base station in the at least three positioning base stations and a positioning tag installed on a target train by using the space-time parameter set; based on the position information of each positioning base station in the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time, the position information of the target train is determined through a fusion positioning algorithm; wherein the fusion positioning algorithm is a positioning algorithm fusing a signal arrival time positioning mechanism and a signal arrival time difference positioning mechanism; and sending the position information of the target train to a user terminal. By using the method provided by the embodiment of the invention, the train positioning can be accurately implemented under the GNSS denial condition.

Description

Technical Field

[0001] The present disclosure relates to the field of navigation and positioning technology, and in particular to a method, device, system, electronic device, computer-readable storage medium, and computer program product for positioning and monitoring a train. Background Art

[0002] With the advancement of technology, more and more wireless communication systems have emerged, providing opportunities for rapid development of communication-based technologies such as navigation and positioning. At the same time, with the continuous improvement of social service industries and the improvement of people's living standards, location-based services (such as train positioning) are becoming more and more common.

[0003] The Global Navigation Satellite System (GNSS) is widely used in train positioning. GNSS determines a vehicle's position by receiving satellite signals. Its positioning principle is based on measuring the distance between satellites and ground-based receivers. Generally, GNSS can provide relatively accurate train location information.

[0004] However, in some special environments (for example, when trains pass through tunnels or mountainous areas), the existing GNSS-based solutions used for train positioning suffer from reduced positioning accuracy and low reliability, which poses a huge challenge to the safe operation and precise scheduling of trains. Summary of the Invention

[0005] In order to solve the above technical problems, the solution of the present disclosure is proposed. Embodiments of the present disclosure provide a method, apparatus, system, electronic device, computer-readable storage medium, and computer program product for positioning and monitoring a train.

[0006] According to a first aspect of an embodiment of the present disclosure, a method for positioning and monitoring a train is provided, wherein the method includes:

[0007] In response to receiving the space-time parameter sets sent by at least three positioning base stations, determining, using the space-time parameter sets, a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train;

[0008] The spatiotemporal parameter set includes a two-way communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, and location information of each of the at least three positioning base stations;

[0009] Wherein, the positioning base station is set along the railway line where the train runs;

[0010] Wherein, the target train is a train that needs to be positioned;

[0011] Determining the location information of the target train by a fusion positioning algorithm based on the location information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time;

[0012] The fusion positioning algorithm is a positioning algorithm that integrates the signal arrival time positioning mechanism and the signal arrival time difference positioning mechanism;

[0013] The location information of the target train is sent to the user terminal.

[0014] According to a second aspect of an embodiment of the present disclosure, there is provided an apparatus for positioning and monitoring a train, wherein the apparatus comprises:

[0015] a transmission time determination unit configured to: in response to receiving a space-time parameter set sent by at least three positioning base stations, determine, using the space-time parameter set, a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train;

[0016] The spatiotemporal parameter set includes a two-way communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, and location information of each of the at least three positioning base stations;

[0017] Wherein, the positioning base station is set along the railway line where the train runs;

[0018] Wherein, the target train is a train that needs to be positioned;

[0019] A fusion positioning solution unit is configured to: determine the position information of the target train by a fusion positioning algorithm based on the position information of each positioning base station of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time;

[0020] The fusion positioning algorithm is a positioning algorithm that integrates the signal arrival time positioning mechanism and the signal arrival time difference positioning mechanism;

[0021] The positioning information pushing unit is configured to send the position information of the target train to the user terminal.

[0022] According to a third aspect of an embodiment of the present disclosure, a system for positioning and monitoring a train is provided, wherein the system includes a positioning tag, a positioning base station, and a data processing device;

[0023] The positioning tag is set on a target train, wherein the target train is a train that needs to be positioned;

[0024] The positioning base station is set along the railway line where the target train runs;

[0025] The positioning tag communicates with the positioning base station based on ultra-wideband signals;

[0026] The data processing equipment includes a data processing device, and the data processing device is the device for positioning monitoring of a train according to claim 9.

[0027] According to the fourth aspect of an embodiment of the present disclosure, an electronic device is provided, comprising: a processor; a memory for storing executable instructions of the processor; the processor for reading the executable instructions from the memory and executing the instructions to implement the method for positioning monitoring of a train described in the present disclosure.

[0028] According to a fifth aspect of an embodiment of the present disclosure, a computer-readable storage medium is provided, wherein the storage medium stores a computer program, and the computer program is used to execute the method for positioning monitoring of a train described in the present disclosure.

[0029] According to a sixth aspect of an embodiment of the present disclosure, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the method for positioning monitoring of a train described in the present disclosure is implemented.

[0030] In summary, the above embodiments of the present disclosure provide a solution for positioning and monitoring trains. On the one hand, by introducing a fusion positioning algorithm combined with ultra-wideband signal ranging (equipped with positioning tags, positioning base stations, and servers that can communicate based on ultra-wideband signals), it is possible to accurately analyze and process the received spatiotemporal parameters, thereby accurately calculating the position information of the positioning tag (i.e., obtaining the position information of the target train) under GNSS denial conditions; and thus being able to locate and display the entire train in real time. When the train passes through a denial environment or other relatively harsh environment, the train's operating conditions can be observed, and in the event of an emergency, timely response can be made to ensure the safety of the train's operation. On the other hand, by introducing a clock synchronization mechanism, the positioning tags and positioning base stations can be time-synchronized and corrected during the data collection phase to ensure the accuracy of the measured parameters, thereby eliminating the need for the server to optimize the time error during the positioning solution phase, thereby reducing the computational load of the data processing unit and improving the response rate of real-time positioning to a certain extent. In addition, since long and heavy-load trains require positioning of each carriage, this positioning method can locate the entire train with fewer positioning tags, reducing the required cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above and other purposes, features, and advantages of the present disclosure will become more apparent through a more detailed description of the embodiments of the present disclosure in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and are not intended to limit the present disclosure. In the drawings, the same reference numerals generally represent the same components or steps.

[0032] Figure 1 is a flow chart of a method for positioning and monitoring a train provided by an exemplary embodiment of the present disclosure;

[0033] Figure 2 is a schematic diagram of bidirectional communication between the positioning base station and the positioning tag provided by an exemplary embodiment of the present disclosure;

[0034] Figure 3 This disclosure Figure 1 An exemplary flow chart of a method for positioning and monitoring a train provided in an embodiment;

[0035] Figure 4 This disclosure Figure 1 Another exemplary flow chart of a method for positioning and monitoring a train provided in an embodiment;

[0036] Figure 5 1 is a schematic structural diagram of an apparatus for positioning and monitoring a train provided by an exemplary embodiment of the present disclosure;

[0037] Figure 6 is a structural diagram of a system for positioning and monitoring a train provided by an exemplary embodiment of the present disclosure;

[0038] Figure 7 This is a schematic diagram of the working principle of the time of arrival (TOA) of the information provided by an exemplary embodiment of the present disclosure;

[0039] Figure 8 This is a schematic diagram of the working principle of time difference of arrival (TDOA) of information provided by an exemplary embodiment of the present disclosure;

[0040] Figure 9 It is a structural diagram of an application embodiment of the electronic device disclosed in the present invention. DETAILED DESCRIPTION

[0041] The present disclosure will be further described below with reference to the embodiments shown in the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the exemplary embodiments described herein.

[0042] It should be noted that the relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure unless specifically stated otherwise.

[0043] Those skilled in the art will understand that the terms "first" and "second" in the embodiments of the present disclosure are only used to distinguish different steps, devices or modules, and do not represent any specific technical meanings, nor do they indicate a necessary logical order between them.

[0044] It should also be understood that in the embodiments of the present disclosure, “a plurality of” may refer to two or more than two, and “at least one” may refer to one, two, or more than two.

[0045] It should also be understood that any component, data or structure mentioned in the embodiments of the present disclosure can generally be understood as one or more, unless explicitly limited or otherwise indicated in the context.

[0046] In addition, the term "and / or" in this disclosure is merely a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this disclosure generally indicates that the related objects are in an "or" relationship.

[0047] It should also be understood that the description of the various embodiments in this disclosure focuses on the differences between the various embodiments, and the same or similar aspects thereof can be referenced with each other. For the sake of brevity, they will not be described one by one.

[0048] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0049] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0050] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0051] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0052] Summary of the invention concept:

[0053] After repeated studies, the inventors of the present disclosure have found that the reasons leading to the problems of the prior art are as follows: When a train (especially a long and heavy-loaded train) passes through a tunnel, mountainous area or an area with tall buildings (if the railway line is close to an urban area), a GNSS blocking environment will be formed, resulting in a decrease in positioning effect or positioning failure. For example, due to the obstruction of the mountain, the satellite signal is completely unable to reach the train, resulting in the failure of GNSS positioning. For another example, in mountainous areas or areas with tall buildings (if the railway line is close to an urban area), the satellite signal may be severely blocked or interfered with, making the GNSS signal weak or even unable to be received. In addition, the body structure of the long and large vehicle itself will also block the GNSS signal, especially for the carriages in the middle and rear of the vehicle, where this blocking effect is more obvious.

[0054] Based on the above reasons, in order to solve the train positioning problem in the above-mentioned GNSS-denied environment, the inventors of the present disclosure conducted a comprehensive analysis of ultra-wideband (UWB), WIFI, Bluetooth, Zigbee and other positioning methods and found that UWB positioning technology has the following significant advantages compared with WIFI, Bluetooth, Zigbee and other positioning methods, specifically including the following aspects: (1) High precision: UWB positioning technology can achieve centimeter-level positioning accuracy, which is crucial for the safe operation of long and large-scale heavy-load trains. In contrast, the accuracy of positioning technologies such as WIFI, Bluetooth and Zigbee is relatively low, and it is difficult to meet the demand for high-precision positioning in railway transportation. (2) Strong anti-interference ability: UWB signals have strong anti-interference ability and can maintain good performance in complex electromagnetic environments. However, the frequency bands used by technologies such as WIFI, Bluetooth and Zigbee are relatively crowded and easily interfered with by other wireless signals, affecting the accuracy and reliability of positioning. (3) Low power consumption: UWB positioning technology has low power consumption and is suitable for long-term operation on long and large-scale heavy-load trains. In contrast, some other positioning technologies have high power consumption, which may put a certain pressure on the train's energy supply. (4) High-speed data transmission: UWB technology has a high data transmission rate and can quickly transmit positioning data, providing real-time location information for the train control system. This is of great significance for ensuring the safe operation and efficient scheduling of trains. However, the data transmission rates of technologies such as WIFI, Bluetooth and Zigbee are relatively low and may not meet the real-time requirements of railway transportation. (5) Strong penetration ability: UWB signals have strong penetration ability and can penetrate obstacles to a certain extent, such as walls in tunnels, thereby achieving effective positioning of trains in special environments. However, the signal penetration ability of technologies such as WIFI, Bluetooth and Zigbee is relatively weak, and the positioning effect in similar environments may not be ideal.

[0055] In view of this, the inventors of the present disclosure propose a solution for positioning and monitoring trains based on UWB positioning technology; please refer to the following embodiments for details.

[0056] Example 1:

[0057] Figure 1 FIG. 1 is a flow chart of a method for positioning and monitoring a train provided by an exemplary embodiment of the present disclosure. Figure 1 The method is executed on a server side, which may include but is not limited to a cloud computing platform or a server dedicated to monitoring train positioning. The method includes:

[0058] S110. In response to receiving a space-time parameter set sent by at least three positioning base stations, determine, using the space-time parameter set, a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train.

[0059] The spatiotemporal parameter set includes a two-way communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, and location information of each of the at least three positioning base stations.

[0060] Wherein, the positioning base station is set along the railway line where the train runs.

[0061] The target train is a train that needs to be positioned.

[0062] It should be noted that the reason why "the space-time parameter sets sent by at least three positioning base stations" are obtained in step S110 is that the underlying principle of the method described in the embodiment of the present disclosure is the three-point positioning principle, also known as the three-side positioning method, which specifically determines the position of the target point by measuring the distance from the target point (i.e., the "train" to be located) to three known position reference points (i.e., the three positioning base stations).

[0063] S120. Determine the location information of the target train by using a fusion positioning algorithm based on the location information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time.

[0064] The fusion positioning algorithm is a positioning algorithm that integrates the signal arrival time positioning mechanism and the signal arrival time difference positioning mechanism.

[0065] The Time of Arrival (TOA) positioning mechanism uses the signal flight time between two asynchronous transceivers to measure the distance between nodes. Its underlying principle is the aforementioned "trilateration." Specifically, the Time of Arrival (TOA) positioning mechanism is summarized as follows:

[0066] Reference Figure 7 , the three circles will intersect at one point, which means that three anchor nodes are needed to obtain three distance information to calculate the location of the target node. After knowing the distance between the target node and the anchor node in the two-dimensional coordinate system, according to the spatial geometric relationship, the coordinate positions of the three fixed anchor nodes base station 1, base station 2, and base station 3 are (x1, y1), (x2, y2), and (x3, y3) respectively. The coordinates of the target node are (x, y). The corresponding distances from the target node to the anchor node are d1, d2, and d3 respectively. The corresponding calculation formula is listed as follows:

[0067]

[0068] By solving the calculation formula, the coordinates of the target node can be obtained as (x, y).

[0069] The Time Differential of Arrival (TDOA) positioning mechanism uses the arrival time difference between the same signal received by different base stations to determine a node's location. Its underlying principle is a variation of the aforementioned "trilateration" method. Specifically, the Time Differential of Arrival (TDOA) positioning mechanism is outlined below:

[0070] Reference Figure 8 , Suppose there are three base stations A, B, and C with known locations and synchronized clocks, and one node D with unknown location. D sends a signal outward, and A, B, and C receive the signal at different times and record the receiving timestamp T A 、T B 、T C Since the distances from D to A, B, and C are different, the time it takes for the signal to reach A, B, and C is also different, and the following three time differences can be obtained:

[0071] ΔT AB =T A -T B

[0072] ΔT AC =T A -T C

[0073] ΔT BC =T B -T C

[0074] Since the clocks between base stations are synchronized, the time difference has nothing to do with clock bias and is only related to the signal propagation time. Assuming that the propagation speed of the UWB signal in the air is c, the following three distance differences can be obtained:

[0075] Δd AB =cΔT AB

[0076] Δd AC =cΔT AC

[0077] Δd BC =cΔT BC

[0078] Since the position of node D is related, the position of node D can be determined by solving the distance difference equation. Assuming the coordinates of node D are (x, y), we have the following set of equations:

[0079]

[0080] Where (x i ,y i ) represents the coordinates of the i-th base station. Since the system of equations has three equations but only two unknowns, the least squares method can be used to find the optimal solution, that is, to minimize the sum of squared residuals of the system of equations.

[0081] In addition, it should be explained that the reason why the location information of the target train is determined by a fusion positioning algorithm is that the essence of wireless positioning based on ultra-wideband signals is to use geometric relationships (i.e., the three-point positioning principle) to solve the target position, but the measurement values ​​in actual scenarios are interfered by factors such as noise, clock errors, and non-line-of-sight (NLOS), resulting in the error of a single positioning method (such as pure TOA or pure TDOA) being difficult to meet high-precision requirements. Since the error sources of TOA and TDOA are different, by fusing the two positioning algorithms, redundant messages can be used to offset the dominant effect of a single error source. For example, the measurement equations of TOA and TDOA are jointly modeled as an overdetermined set of equations, and the optimal solution is found by the least squares method. In essence, this is a weighted average of multi-source observations to suppress the influence of random noise and outliers.

[0082] S130: Send the location information of the target train to the user terminal.

[0083] It should be noted that, since the method described in the above embodiment is executed on the server side, the location information of the target train is sent from the server side to the user terminal, which can be easily viewed by the user, thereby improving the user experience.

[0084] The user terminal may include but is not limited to smart phones, tablet computers and other devices.

[0085] In addition, it should be noted that since the train is in a moving state, when the server receives the "space-time parameter set" and performs positioning calculations, the train has actually moved forward a distance from the position at the time the "space-time parameters" were sent. However, considering that the "ultra-wideband signal" flies at the speed of light, the train's movement speed is negligible compared to the speed of light, so the position of the positioning solution is approximately considered to be the train's true position. In addition, the computing power of the server that generally performs positioning solutions is sufficient, so the solution time can be ignored (that is, an instant response can be achieved). In other words, it can be considered that "solution time" does not affect the train's positioning accuracy.

[0086] As described above, the method for positioning and monitoring a train provided in Example 1 of the present disclosure, by introducing a fusion positioning algorithm, can accurately analyze and process the received spatiotemporal parameters, thereby accurately calculating the position information of the positioning tag; that is, obtaining the position information of the target train.

[0087] Example 2:

[0088] Based on the above embodiment, the two-way communication timestamp sequence includes timestamp T1, timestamp T2, timestamp T3 and timestamp T4. Figure 2 , receiving end A is the positioning tag; transmitting end B is the positioning base station. Timestamp T1 is the moment when the positioning base station sends an ultra-wideband signal to the positioning tag; timestamp T2 is the moment when the positioning tag receives the ultra-wideband signal; timestamp T3 is the moment when the positioning tag sends a reply signal to the positioning base station; the reply signal includes information representing timestamps T2 and T3, and the reply signal is an ultra-wideband signal; timestamp T4 is the moment when the positioning base station receives the reply signal.

[0089] Example 3:

[0090] Based on the above embodiment, refer to Figure 3 Step S110 “using the spatiotemporal parameter set to determine the one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on the target train” may include the following steps:

[0091] S1110 : For any positioning base station among the at least three positioning base stations, determine a timestamp T1 , a timestamp T2 , a timestamp T3 , and a timestamp T4 corresponding to the positioning base station from the spatiotemporal parameter set.

[0092] S1120 : Calculate the difference between timestamp T4 and timestamp T1 and record it as the first time.

[0093] S1130 : Calculate the difference between timestamp T3 and timestamp T2, and record it as the second time.

[0094] S1140. Calculate the time difference between the first time and the second time, and divide the difference by two to obtain the one-way transmission time of the ultra-wideband signal between the corresponding positioning base station and the positioning tag installed on the target train.

[0095] Optionally, in a specific example, the above steps S1120 to S1140 can be expressed using the following calculation formula:

[0096]

[0097] Among them, t prop Indicates the one-way transmission time of the ultra-wideband signal. Figure 2 , the "one-way" corresponds to TpropA and TpropB. Figure 2 , the first time is Tround, the second time is Treply.

[0098] Optionally, the timestamp T1, timestamp T2, timestamp T3 and timestamp T4 are all timestamps calibrated based on a time synchronization protocol.

[0099] As a specific example, the time synchronization protocol may be the Network Time Protocol (NTP). NTP is a protocol for time synchronization over a network. When connected to a network, both the positioning base station and the positioning tag can obtain accurate time information from an NTP server and adjust their local clocks accordingly. NTP synchronization typically offers millisecond-level accuracy and does not require additional hardware, making it low-cost and easy to implement.

[0100] Example 4:

[0101] Based on the above embodiment, refer to Figure 4 Step S120 of "determining the location information of the target train by using a fusion positioning algorithm based on the location information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time" may include:

[0102] S1210: Based on the position information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a ranging equation is constructed using a signal arrival time positioning mechanism.

[0103] Optionally, step S1210 may be implemented in the following available manners:

[0104] First, for each positioning base station, the product of the ultra-wideband signal propagation speed and the one-way transmission time of the ultra-wideband signal corresponding to the positioning base station is calculated, and recorded as the straight-line distance observation value of the positioning base station; wherein the ultra-wideband signal propagation speed is the speed of light; then, using the position information of each positioning base station and the corresponding straight-line distance observation value, the unknown position coordinates of the positioning tag are used as the variables to be determined, and the ranging equation is constructed.

[0105] As a specific example, the “distance measurement equation” described in the above implementation can be expressed based on the following calculation formula:

[0106]

[0107] Among them, d i represents the straight-line distance observation value corresponding to the i-th positioning base station; (x, y) represents the unknown position coordinates of the positioning tag; (x i ,y i ) represents the location information of the positioning base station; represents the one-way transmission time of the ultra-wideband signal corresponding to the i-th positioning base station; c represents the speed of light.

[0108] S1220: Based on the location information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a distance difference constraint equation is constructed using a signal arrival time difference positioning mechanism.

[0109] Optionally, step S1220 may be implemented in the following available manners:

[0110] Step 1) Determine all base station groups among the at least three positioning base stations; wherein, each of the base station groups includes two positioning base stations.

[0111] Step 2) for each base station group, determining a difference in one-way transmission time of ultra-wideband signals corresponding to two positioning base stations in the base station group, recorded as a one-way transmission time difference;

[0112] Step 3) calculating the product of the transmission speed of the ultra-wideband signal and the one-way transmission time difference corresponding to each of the base station groups, and recording it as the one-way transmission distance difference; wherein the propagation speed of the ultra-wideband signal is the speed of light;

[0113] Step 4) Using the location information of each positioning base station in the base station group and the corresponding one-way transmission distance difference, and taking the unknown position coordinates of the positioning tag as the variable to be determined, the distance difference constraint equation is constructed.

[0114] As a specific example, for any of the base station groups, which includes positioning base station j and positioning base station k, the one-way transmission time difference is defined as:

[0115]

[0116] Wherein, j and k both represent the sequence number of the positioning base station in the at least three positioning base stations, and are positive integers; Δt jk Represents the one-way transmission time difference between positioning base station j and positioning base station k; represents the one-way transmission time of the ultra-wideband signal corresponding to the positioning base station j; represents the one-way transmission time of the ultra-wideband signal corresponding to the positioning base station k.

[0117] The distance difference constraint equation can be expressed as the following calculation formula:

[0118] d j -d k =c·Δt jk (4)

[0119] Among them, d j represents the straight-line distance observation value corresponding to the j-th positioning base station; d k Represents the straight-line distance observation value corresponding to the k-th positioning base station.

[0120] In addition, it should be noted that in this example, d j d k It can be determined by calculation based on the calculation formula (2) in the implementation of step S1210 above.

[0121] S1230: Construct a target optimization function through weighted fusion based on the ranging equation and the distance difference constraint equation corresponding to each positioning base station.

[0122] Optionally, step S1230 may be implemented in the following available manners:

[0123] Ia. Based on the distance measurement equation corresponding to each positioning base station, a distance measurement equation error function of the positioning base station is constructed.

[0124] Ib. Based on the distance difference constraint equation corresponding to each base station group, construct an error function of the distance difference constraint equation of the base station group.

[0125] Ic. Based on matching the preset ranging equation weight and ranging equation error function of each positioning base station, matching the preset distance difference constraint weight and distance difference constraint equation error function of each base station group, constructing a weighted least squares objective function as the target optimization function.

[0126] As a specific example, in step Ia, based on the above calculation formula (2), the following calculation formula (5) can be obtained as the ranging equation error function.

[0127]

[0128] Among them, d i represents the straight-line distance observation value corresponding to the i-th positioning base station; (x, y) represents the unknown position coordinates of the positioning tag; (x i ,y i ) represents the location information of the positioning base station.

[0129] As a specific example, in step Ib, the following calculation formula (6) can be obtained based on the above calculation formula (4) by transposing the terms, as the error function of the distance difference constraint equation.

[0130] (d j -d k )-c·Δt jk (6)

[0131] Among them, d j represents the straight-line distance observation value corresponding to the j-th positioning base station; d k represents the straight-line distance observation value corresponding to the k-th positioning base station; Δt jk represents the one-way transmission time difference between positioning base station j and positioning base station k; c represents the speed of light.

[0132] As a specific example, in step Ic, the weighted least squares objective function may be calculated as follows: (7) to (8).

[0133]

[0134] Among them, w i represents the preset ranging equation weight of the i-th positioning base station; jk represents the preset distance difference constraint weight corresponding to the base station group including positioning base station j and positioning base station k.

[0135] S1240: Solve the target optimization function to obtain the position coordinates of the positioning tag as the position information of the target train.

[0136] It should be noted that the present disclosure does not limit the method for solving the objective optimization function. For example, it may include but is not limited to analytical solutions (specifically, such as the normal equation method and the QR decomposition method) and iterative optimization methods (specifically, such as the Gauss-Newton method and the gradient descent method).

[0137] As described above, the method for positioning and monitoring a train provided by the above embodiments of the present disclosure, on the one hand, by introducing a fusion positioning algorithm combined with ultra-wideband signal ranging (equipped with positioning tags, positioning base stations, and servers that can communicate based on ultra-wideband signals), can accurately analyze and process the received spatiotemporal parameters, thereby accurately calculating the position information of the positioning tag (i.e., obtaining the position information of the target train) under GNSS denial conditions; and thus can locate and display the entire train in real time, and observe the train's operation when the train passes through a denial environment or other relatively harsh environments, so that timely responses can be made in case of emergencies to ensure the safety of the train's operation. On the other hand, by introducing a clock synchronization mechanism, the positioning tags and positioning base stations can be time-synchronized and corrected during the data collection phase to ensure the accuracy of the measured parameters, thereby eliminating the need for the server to optimize the time error during the positioning solution phase, thereby reducing the computational load of the data processing unit and improving the response rate of real-time positioning to a certain extent. In addition, since long and heavy-load trains require positioning of each carriage, this positioning method can locate the entire train with fewer positioning tags, reducing the required cost.

[0138] Example 5:

[0139] It should be understood that the aforementioned embodiments herein with respect to the method for monitoring the location of a train can also be similarly applied to the following apparatus for monitoring the location of a train with similar extensions.

[0140] Figure 5 FIG. 1 is a schematic diagram of a structure of an apparatus for positioning and monitoring a train provided by an exemplary embodiment of the present disclosure. Figure 5 , the device comprises:

[0141] The transmission time determination unit 510 is configured to, in response to receiving a spatiotemporal parameter set transmitted by at least three positioning base stations, use the spatiotemporal parameter set to determine the one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train. The spatiotemporal parameter set includes a bidirectional communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, as well as location information for each of the at least three positioning base stations. The positioning base stations are located along the railway line along which the train is traveling. The target train is the train to be located.

[0142] The fused positioning solution unit 520 is configured to determine the location information of the target train using a fused positioning algorithm based on the location information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time. The fused positioning algorithm is a positioning algorithm that combines a signal arrival time positioning mechanism with a signal arrival time difference positioning mechanism.

[0143] The positioning information pushing unit 530 is configured to send the position information of the target train to the user terminal.

[0144] As described above, the device for positioning and monitoring trains provided in Example 1 of the present disclosure can accurately analyze and process the received spatiotemporal parameters by introducing a fusion positioning algorithm, thereby accurately calculating the position information of the positioning tag; that is, obtaining the position information of the target train.

[0145] Example 6:

[0146] Based on the above embodiments, the present disclosure provides a system for positioning and monitoring trains, comprising a positioning tag, a positioning base station, and a data processing device. The positioning tag is mounted on a target train; the positioning base station is located along the railway line along which the target train travels; the positioning tag and the positioning base station communicate using ultra-wideband signals; and the data processing device comprises a data processing device, which is the device for positioning and monitoring trains described in Example 5. The target train is the train to be positioned.

[0147] As a specific example, refer to Figure 6 , the system includes a communication-connected positioning tag (ie Figure 6 "Data tags" shown), positioning base station (i.e. Figure 6 "Data acquisition" shown), data transmission unit (i.e. Figure 6 "Data transmission" shown) and the data processing unit (ie Figure 6 “Data processing” as shown).

[0148] Optionally, the positioning tag can communicate with the positioning base station in two directions, and the communication signal is an ultra-wideband signal.

[0149] Optionally, the positioning tag is set on the body of the train, so that the position of the train can be indirectly determined by identifying the position of the positioning tag.

[0150] Optionally, the positioning tag is an ultra-wideband tag, i.e., a UWB tag. The disclosed embodiments do not limit the type of UWB tag; for example, it can be a "vehicle / asset-specific" tag, which features include a large-capacity battery or external power supply, a strong magnetic suction cup design for easy fixation, and is suitable for vehicle-mounted or large equipment positioning.

[0151] Reference Figure 6 The positioning base station is used to forward the "space-time parameter set" to the data processing unit via the data transmission unit.

[0152] Optionally, the positioning base station is an ultra-wideband base station, that is, a UWB base station.

[0153] Optionally, the data processing unit is a data processing server (ie, Figure 6 The server may be configured with "positioning system software" which, when running, may execute the methods for positioning and monitoring a train as described in Examples 1 to 4, thereby achieving real-time positioning of the train.

[0154] Optionally, the system further includes a clock synchronization unit ( Figure 6 (not shown). The clock synchronization unit is communicatively connected to the positioning tag for correcting the time error of the positioning tag; the clock synchronization unit is communicatively connected to the positioning base station for correcting the time error of the positioning base station. It should be noted that clock synchronization error correction is an important part of improving the accuracy of the precise positioning system based on ultra-wideband technology. In practical applications, due to a certain deviation between the clocks of the UWB tag and the UWB base station, errors will be generated in the measured time of arrival (TOA) and time difference of arrival (TDOA), thereby affecting the accuracy of positioning. Therefore, it is necessary to adopt clock synchronization error correction technology to reduce this error. The basic idea of ​​clock synchronization error correction is to keep the clocks of the transmitting source and the receiving terminal highly consistent in some way, thereby reducing the impact of clock deviation on positioning. As an optional example, the clock synchronization unit can be an NTP network time protocol (NTP) server. Specifically, NTP is a protocol for time synchronization over a network. When there is a network connection, the UWB tag (as a transmitting source) and the UWB base station (as a receiving terminal) can obtain accurate time information through the NTP server and adjust the local clock. NTP synchronization typically provides millisecond-level accuracy, meeting the precision requirements for train positioning. Furthermore, NTP synchronization requires no additional hardware, making it low-cost and easy to implement.

[0155] Optionally, there are multiple positioning tags, and the multiple positioning tags are distributed along the length of the train on the body of the train. It is understandable that on a long and heavy-load train, UWB tags are installed at the front, rear and key carriages along the length of the vehicle to ensure the integrity and positioning accuracy of the train body. Each positioning tag is positioned through embodiments 1 to 4 of the present disclosure, and then the position information of each positioning tag is integrated to obtain the complete positioning parameters of the train.

[0156] Optionally, there are multiple positioning base stations, and the multiple positioning base stations are distributed along the target railway, so that the ultra-wideband signal sent by the positioning tag is received while the train is running on the target railway. It should be noted that the deployment position of the positioning base station along the target railway can be limited according to the effective receiving radius of the ultra-wideband signal sent by the positioning tag. For example, UWB base stations can be installed at specific locations along the target railway, so that these UWB base stations and the UWB tags set on the train form a positioning network for receiving the ultra-wideband signal emitted by the UWB tag. The specific locations may include but are not limited to tunnel entrances and exits, both ends of bridges, near station platforms, and beside the tracks at certain intervals.

[0157] Optionally, refer to Figure 6 The data transmission unit includes a convergence switch and multiple POE (Power over Ethernet) switches. It should be noted that a POE switch is a network device that transmits both data and power via Ethernet cables. This eliminates the need for independent power supplies for UWB base stations, significantly simplifying wiring costs. Its core functions include data transmission (supporting the network communication functions of traditional switches) and remote power supply (providing DC power to terminal devices via network cables, with power supply standards ranging from 15.4W to 100W).

[0158] Optionally, the number of the multiple POE switches matches the number of the positioning base stations. The signal input of each POE switch is communicatively connected to the signal output of the corresponding positioning base station, and the signal output of each POE switch is communicatively connected to the signal input of the aggregation switch. It is understood that setting a one-to-one mapping between POE switches and positioning base stations can enhance the stability of data transmission.

[0159] Optionally, the signal output end of the aggregation switch is used to communicate with the signal input end of the data processing unit. The aggregation switch is an intermediate-level device in the three-layer network architecture (access layer, aggregation layer, core layer). It is mainly responsible for connecting and managing multiple POE (access layer) switches, aggregating scattered data and forwarding it to the core layer, and then delivering it to the data processing unit. Its core goal is to reduce the data processing burden of the core layer, optimize network performance, and achieve strategic management (such as routing control, security filtering, etc.). It should be noted that communication between the UWB base station and the POE switch, between the POE switch and the aggregation switch, and between the aggregation switch and the data processing unit can all be achieved through wired connections, for example, through network optical fiber connections and networking.

[0160] As described above, the system for positioning and monitoring trains provided by the embodiments of the present disclosure, based on the powerful signal penetration and anti-multipath interference capabilities of ultra-wideband technology, can maintain stable signal transmission in GNSS-denied environments. Furthermore, by introducing a fusion positioning algorithm (i.e., the methods described in Embodiments 1 to 4 above) and an error correction unit, the positioning accuracy of the system can be greatly improved. Furthermore, since long, marshaled, and heavy-loaded trains require the positioning of each carriage, the system for positioning and monitoring trains provided by the embodiments of the present disclosure can locate the entire train with fewer positioning tags, thereby reducing costs to a certain extent.

[0161] Example 7:

[0162] In addition, an embodiment of the present disclosure also provides an electronic device, including: a memory for storing a computer program; a processor for executing the computer program stored in the memory, and when the computer program is executed, the method for positioning and monitoring a train described in any of the above embodiments of the present disclosure is implemented.

[0163] Figure 9 This is a schematic diagram of the structure of an application embodiment of the electronic device disclosed in the present invention. Figure 9 The electronic device according to the embodiment of the present disclosure is described. The electronic device may be either or both of the first device and the second device, or a standalone device independent of them, and the standalone device may communicate with the first device and the second device to receive collected input signals from them.

[0164] like Figure 9As shown, the electronic device includes one or more processors and a memory. The processor may be a central processing unit (CPU) or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. The memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory, etc. The non-volatile memory may, for example, include read-only memory (ROM), a hard disk, a flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor may execute the program instructions to implement the method for positioning monitoring of a train and / or other desired functions of the various embodiments of the present disclosure described above.

[0165] In one example, the electronic device may further include an input device and an output device, wherein these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown). Furthermore, the input device may include, for example, a keyboard, a mouse, and the like. The output device may output various information to the outside, including determined distance information, direction information, and the like. The output device may include, for example, a display, a speaker, a printer, a communication network, and remote output devices connected thereto.

[0166] Of course, to simplify, Figure 9 Only some of the components related to the present disclosure in the electronic device are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, the electronic device may further include any other appropriate components according to specific application scenarios.

[0167] In addition to the above-mentioned methods and devices, an embodiment of the present disclosure may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method for positioning monitoring of a train according to various embodiments of the present disclosure described in the above part of this specification.

[0168] The computer program product may be written in any combination of one or more programming languages ​​to implement the operations of the disclosed embodiments, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0169] In addition, an embodiment of the present disclosure may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, enable the processor to execute the steps of the method for positioning monitoring of a train according to various embodiments of the present disclosure described in the above part of this specification.

[0170] The computer-readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can, for example, include but is not limited to a system, device or component of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0171] Those skilled in the art will understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk, etc. Various media that can store program codes.

[0172] The basic principles of the present disclosure have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this disclosure are merely illustrative and not restrictive, and should not be construed as necessarily possessed by each embodiment of the present disclosure. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, rather than as limitations. These details do not limit the present disclosure to necessarily being implemented using these specific details.

[0173] Each embodiment in this specification is described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. References to the same or similar parts between the various embodiments are sufficient. For system embodiments, since they largely correspond to method embodiments, their description is relatively simple. For relevant parts, references to the description of the method embodiments are sufficient.

[0174] The block diagrams of the devices, devices, equipment, and systems involved in this disclosure are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0175] The methods and apparatus of the present disclosure may be implemented in many ways. For example, the methods and apparatus of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above unless otherwise specified. In addition, in some embodiments, the present disclosure may also be implemented as programs recorded in a recording medium, which include machine-readable instructions for implementing the methods according to the present disclosure. Thus, the present disclosure also covers recording media that store programs for executing the methods according to the present disclosure.

[0176] It should also be noted that in the apparatus, device, and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0177] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0178] The above description has been provided for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for positioning and monitoring a train, characterized in that: The method comprises: In response to receiving the space-time parameter sets sent by at least three positioning base stations, determining, using the space-time parameter sets, a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train; The spatiotemporal parameter set includes a two-way communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, and location information of each of the at least three positioning base stations; Wherein, the positioning base station is set along the railway line where the train runs; Wherein, the target train is a train that needs to be positioned; Determining the location information of the target train by a fusion positioning algorithm based on the location information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time; The fusion positioning algorithm is a positioning algorithm that integrates the signal arrival time positioning mechanism and the signal arrival time difference positioning mechanism; The location information of the target train is sent to the user terminal.

2. The method according to claim 1, characterized in that The two-way communication timestamp sequence includes timestamp T1, timestamp T2, timestamp T3 and timestamp T4; wherein, Timestamp T1 is the moment when the positioning base station sends the ultra-wideband signal to the positioning tag; Timestamp T2 is the moment when the positioning tag receives the ultra-wideband signal; Timestamp T3 is the time when the positioning tag sends a reply signal to the positioning base station; wherein the reply signal includes information representing the timestamps T2 and T3, and the reply signal is an ultra-wideband signal; Timestamp T4 is the time when the positioning base station receives the reply signal.

3. The method according to claim 2, characterized in that Determining a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train using the time-space parameter set includes: For any positioning base station among the at least three positioning base stations, determine a timestamp T1, a timestamp T2, a timestamp T3, and a timestamp T4 corresponding to the positioning base station from the time-space parameter set; Calculate the difference between timestamp T4 and timestamp T1, and record it as the first time; Calculate the difference between timestamp T3 and timestamp T2, and record it as the second time; The time difference between the first time and the second time is calculated and divided by two to obtain the one-way transmission time of the ultra-wideband signal between the corresponding positioning base station and the positioning tag installed on the target train.

4. The method according to claim 2, characterized in that Determining the position information of the target train by using a fusion positioning algorithm based on the position information of each of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time includes: Based on the location information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a ranging equation is constructed using a signal arrival time positioning mechanism; Based on the location information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a distance difference constraint equation is constructed using the signal arrival time difference positioning mechanism; Based on the ranging equation and the distance difference constraint equation corresponding to each positioning base station, constructing a target optimization function through weighted fusion; Solve the target optimization function to obtain the position coordinates of the positioning tag as the position information of the target train.

5. The method according to claim 4, characterized in that: Based on the location information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a ranging equation is constructed using the signal arrival time positioning mechanism, including: For each positioning base station, calculate the product of the ultra-wideband signal propagation speed and the ultra-wideband signal one-way transmission time corresponding to the positioning base station, and record it as the straight-line distance observation value of the positioning base station; wherein the ultra-wideband signal propagation speed is the speed of light; The distance measurement equation is constructed by using the position information of each positioning base station and the corresponding straight-line distance observation value and taking the unknown position coordinates of the positioning tag as the variable to be determined.

6. The method according to claim 4, characterized in that: Based on the location information of each positioning base station and the corresponding ultra-wideband signal one-way transmission time, a distance difference constraint equation is constructed using the signal arrival time difference positioning mechanism, including: Determine all base station groups among the at least three positioning base stations; wherein each of the base station groups includes two of the positioning base stations; For each base station group, determining a difference in one-way transmission time of ultra-wideband signals corresponding to two positioning base stations in the base station group, and recording the difference as a one-way transmission time difference; Calculating the product of the transmission speed of the ultra-wideband signal and the one-way transmission time difference corresponding to each base station group, and recording it as the one-way transmission distance difference; wherein the propagation speed of the ultra-wideband signal is the speed of light; The distance difference constraint equation is constructed by utilizing the position information of the positioning base station in each base station group and the corresponding one-way transmission distance difference and taking the unknown position coordinates of the positioning tag as the variable to be determined.

7. The method according to claim 6, characterized in that Based on the ranging equation and the distance difference constraint equation corresponding to each positioning base station, a target optimization function is constructed through weighted fusion, including: Based on the distance measurement equation corresponding to each positioning base station, construct a distance measurement equation error function of the positioning base station; Constructing an error function of the distance difference constraint equation of the base station group based on the distance difference constraint equation corresponding to each base station group; Based on matching the preset ranging equation weight and ranging equation error function of each positioning base station, matching the preset distance difference constraint weight and distance difference constraint equation error function of each base station group, a weighted least squares objective function is constructed as the target optimization function.

8. The method according to any one of claims 1 to 7, characterized in that: The timestamp T1 , timestamp T2 , timestamp T3 and timestamp T4 are all timestamps calibrated based on a time synchronization protocol.

9. A device for positioning and monitoring a train, characterized in that: The device comprises: a transmission time determination unit configured to: in response to receiving a space-time parameter set sent by at least three positioning base stations, determine, using the space-time parameter set, a one-way transmission time of an ultra-wideband signal between each of the at least three positioning base stations and a positioning tag installed on a target train; The spatiotemporal parameter set includes a two-way communication timestamp sequence between each of the at least three positioning base stations and the positioning tag, and location information of each of the at least three positioning base stations; Wherein, the positioning base station is set along the railway line where the train runs; Wherein, the target train is a train that needs to be positioned; A fusion positioning solution unit is configured to: determine the position information of the target train by a fusion positioning algorithm based on the position information of each positioning base station of the at least three positioning base stations and the corresponding ultra-wideband signal one-way transmission time; The fusion positioning algorithm is a positioning algorithm that integrates the signal arrival time positioning mechanism and the signal arrival time difference positioning mechanism; The positioning information pushing unit is configured to send the position information of the target train to the user terminal.

10. A system for positioning and monitoring a train, characterized in that: The system includes a positioning tag, a positioning base station and a data processing device; The positioning tag is set on a target train, wherein the target train is a train that needs to be positioned; The positioning base station is set along the railway line where the target train runs; The positioning tag communicates with the positioning base station based on ultra-wideband signals; The data processing equipment includes a data processing device, and the data processing device is the device for positioning monitoring of a train according to claim 9.

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