A positioning method, system, device and storage medium based on track transponder

Abstract

The present disclosure belongs to the field of train control, and proposes a positioning method, system, device and storage medium based on a track transponder, the method comprising: determining the differential correction data of the satellite signal at the first moment according to the satellite observation data at the first moment and the position information provided by the transponder; determining the real-time train positioning at the second moment according to the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment. On the one hand, the present disclosure can effectively improve the train positioning accuracy between adjacent transponders, and on the other hand, it combines the known and high-precision position information of the transponder on the train track with the satellite observation data collected by the corresponding GNSS receiver module to realize the function of the base station in the RTK positioning technology, effectively saving the construction and maintenance costs of the base station, and realizing continuous high-precision positioning of the train without building the base station in the RTK positioning technology.

Description

Technical Field

[0001] The present invention relates to the field of train control, and in particular to a positioning method, system, device and storage medium based on a track transponder. Background Art

[0002] In the train positioning system, the transponder plays a vital role. The precise position information stored in the ground transponder is read by the on-board query device to achieve accurate correction of the train position, effectively eliminating the accumulated position deviation caused by sensor errors, wheel wear and other factors. GNSS (Global Navigation Satellite System) is widely used in train positioning systems due to its advantages of global all-weather, high positioning accuracy, and no accumulation of position errors over time. In the application scenario of high-precision train positioning, RTK (Real-Time Kinematic) positioning technology plays an important role. The core idea of ​​RTK positioning technology is to use the known precise position of the base station and GNSS observation value information (pseudorange, carrier), and calculate and transmit the differential correction data of the satellite signal in real time to the mobile station through the wireless communication network. The mobile station combines the satellite signals observed by itself with the received differential correction data to achieve fusion positioning, eliminate or greatly reduce various error sources such as satellite orbit errors and ionospheric delays, and achieve centimeter-level or even higher precision position information. However, RTK technology requires the construction and maintenance of base stations, and its effective range is usually no more than 20 kilometers. Given the extensive coverage of the railway network, this will undoubtedly greatly increase the construction and maintenance costs of the base stations. Summary of the invention

[0003] In view of the above problems, the present disclosure proposes a positioning method based on a track transponder, the method comprising:

[0004] Determining differential correction data of the satellite signal at the first moment according to the satellite observation data at the first moment and the position information provided by the transponder;

[0005] The real-time train positioning at the second moment is determined based on the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment.

[0006] Furthermore, the train position information at the first moment is pseudo reference station position information, and the pseudo reference station position information is determined by the position information provided by the transponder at the first moment.

[0007] Furthermore, the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment both include pseudorange and carrier phase observation data.

[0008] Further, determining the real-time train positioning at the second moment according to the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment includes:

[0009] Constructing a single-difference observation model according to pseudo-range and carrier phase observation data at the first moment and the second moment;

[0010] Determine the reference satellite, and construct a double-difference observation model based on the reference satellite and the single-difference observation model;

[0011] The real-time train position coordinates and ambiguity floating-point solution at the second moment are determined based on the double-difference observation model.

[0012] The present disclosure also provides a positioning system based on a track transponder, the system comprising: a transponder information receiving module, a satellite signal receiving module, a pseudo reference station module and a train control system.

[0013] A satellite signal receiving module, used for receiving satellite observation data at a first moment and a second moment;

[0014] A transponder information receiving module, used for receiving location information provided by the transponder;

[0015] The train control system is used to receive the position information provided by the transponder and transmit it to the pseudo reference station module;

[0016] The pseudo reference station module is used to determine the differential correction data of the satellite signal at the first moment based on the satellite observation data at the first moment and the position information provided by the transponder, and is also used to determine the real-time train positioning at the second moment based on the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment.

[0017] Furthermore, the train position information at the first moment is pseudo reference station position information, and the pseudo reference station position information is determined by the position information provided by the transponder at the first moment.

[0018] Furthermore, the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment both include pseudorange and carrier phase observation data.

[0019] Furthermore, the pseudo reference station module includes a first submodule, a second submodule and a third submodule.

[0020] The first submodule is used to construct a single-difference observation model according to the pseudo-range and carrier phase observation data at the first moment and the second moment;

[0021] The second submodule is used to determine the reference satellite and construct a double difference observation model based on the reference satellite and the single difference observation model;

[0022] The third submodule is used to determine the real-time train position coordinates and ambiguity floating-point solution at the second moment according to the double-difference observation model.

[0023] The present disclosure also provides an electronic device, the electronic device comprising at least one processor and at least one memory, the memory being data-connected to the processor, wherein:

[0024] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the positioning method based on the track transponder described in the present disclosure.

[0025] The present disclosure also provides a computer storage medium storing one or more instructions, which, when executed by one or more computers, enable the one or more computers to implement the track transponder-based positioning method described in the present disclosure.

[0026] The positioning method, system, device and storage medium based on track transponders disclosed in the present invention can, on the one hand, effectively improve the train positioning accuracy between adjacent transponders, and on the other hand, realize the function of the base station in the RTK positioning technology by combining the known and high-precision position information of the transponder on the train track and the satellite observation data collected by the corresponding GNSS receiver module, effectively saving the construction and maintenance costs of the base station, and realizing continuous high-precision positioning of the train without building the base station in the RTK positioning technology. In an open environment, the satellite signal differential correction data at time K calculated by the pseudo-base station has a certain timeliness, which can realize high-precision positioning of trains within a certain distance, and reduce the laying density of transponders to the greatest extent, saving the cost of transponder construction and maintenance, reducing equipment construction and maintenance costs, and greatly saving system construction and maintenance costs; at the same time, because the GNSS receiver module and the transponder information receiving module can establish a reliable and stable communication mechanism with the train control system, there is no need to use a wireless network to establish a relationship between a base station and a mobile station like traditional RTK positioning technology, which significantly reduces communication delays and simplifies system equipment.

[0027] Other features and advantages of the present disclosure will be described in the following description, and partly become apparent from the description, or be understood by implementing the present disclosure. The purpose and other advantages of the present disclosure can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the flow of a positioning method based on a track transponder in an embodiment of the present disclosure is shown;

[0030] Figure 2 A schematic diagram of a positioning system based on a track transponder in an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0032] RTK technology requires the construction and maintenance of base stations, and the effective range is usually no more than 20 kilometers. In view of the wide coverage of the railway network, the construction and maintenance costs of the base stations are undoubtedly greatly increased. This disclosure proposes a positioning method based on a track transponder, which specifically relates to an asynchronous RTK positioning system. Figure 1 The figure shows a schematic flow chart of a positioning method based on a track transponder in an embodiment of the present disclosure. Figure 1 The method includes determining the differential correction data of the satellite signal at the first moment based on the satellite observation data at the first moment and the position information provided by the transponder; and determining the real-time train positioning at the second moment based on the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment.

[0033] In the embodiment of the present disclosure, the moment when the train passes a certain transponder in the running direction is defined as the first moment, and any moment between the next transponder in the running direction is defined as the second moment. The expressions of the first moment and the second moment are only for distinction and have no other meaning that affects the technical solution of the present disclosure.

[0034] Specifically, in the embodiment of the present disclosure, the position information provided by the transponder at the first moment is used as the known precise position of the reference station (the pseudo reference station module of the present disclosure), that is, the train position information at the first moment is the pseudo reference station position information, and the pseudo reference station position information is determined by the position information provided by the transponder at the first moment.

[0035] Specifically, in the embodiments of the present invention, the GNSS differential positioning methods mainly include pseudorange differential positioning and carrier phase differential, among which the pseudorange differential method can generally only achieve nanometer-level positioning accuracy and is difficult to apply in precise positioning; while the carrier phase has a short wavelength and is less affected by noise, and the differential (single difference and double difference) form can eliminate the satellite and receiver clock errors and atmospheric delay errors, and can achieve centimeter-level positioning accuracy by successfully fixing the ambiguity. Based on this, the differential correction data of the pseudo-reference station (the reference station in the asynchronous RTK positioning system) at the first moment and the pseudo-reference station (the mobile station in the asynchronous RTK positioning system) at the second moment, and the satellite observation data all include pseudorange and carrier phase observation data, and the asynchronous RTK positioning of the present invention is described together by the two phase observation data.

[0036] Specifically, in the present disclosure, determining the real-time train positioning at the second moment according to the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment includes:

[0037] Constructing a single-difference observation model according to pseudo-range and carrier phase observation data at the first moment and the second moment;

[0038] Determine the reference satellite, and construct a double-difference observation model based on the reference satellite and the single-difference observation model;

[0039] The real-time train position coordinates and ambiguity floating-point solution at the second moment are determined based on the double-difference observation model.

[0040] In the present disclosure, the specific contents of the track transponder positioning method of the present disclosure are described in detail through specific embodiments:

[0041] In the present disclosure, the GNSS pseudorange observation equation and the carrier phase observation equation can be expressed as follows:

[0042] (1)

[0043] in, and They represent the GNSS pseudorange and carrier phase observations at time k, represents the actual distance between the satellite and the receiver at time k; Represents the speed of light propagation; and represent the errors of receiver and satellite clocks respectively; and They represent the ionospheric error and tropospheric delay error of the satellite signal propagating in the atmosphere at time k respectively; Indicates the phase wavelength of the carrier; represents the integer ambiguity in weeks; and They represent the observation noise of pseudorange and carrier vector respectively.

[0044] The carrier phase single difference positioning principle is a method in which the base station receiver and the mobile station receiver perform differential elimination of intermediate errors on the observations of the same satellite. This disclosure takes the carrier phase differential relative positioning as an example to describe in detail the satellite differential correction number and the differential positioning working method:

[0045] In the present disclosure, the carrier phase equation of the reference station b (pseudo reference station at time k / first time) is expressed as:

[0046] (2)

[0047] In formula (2), q represents any first satellite; represents the carrier phase observation of GNSS at time k (i.e., the first time), i.e., the differential correction data of the satellite signal at the first time; Indicates satellite q The actual distance to the base station b receiver at time k; Represents the speed of light propagation; and represent the base station b receiver and satellite q Clock error; and Satellite q Ionospheric error and tropospheric delay error at time k when the signal propagates in the atmosphere; Indicates the phase wavelength of the carrier; represents the integer ambiguity of the reference station b in weeks; It should be noted that the carrier phase equation of the reference station b is also the carrier phase equation of the pseudo reference station k at the transponder at the first moment in the present disclosure. The distance between the pseudo reference station and the satellite at the first moment is Represents the location of the train's known balises.

[0048] The carrier phase equation of the mobile station r (pseudo reference station at time k+i / second time) is expressed as:

[0049] (3)

[0050] In formula (3), q represents any first satellite; represents the carrier phase observation of GNSS at time k+i (i.e. the second time); Indicates satellite q The actual distance to the receiver of mobile station r at time k+i; Represents the speed of light propagation; and represent the mobile station r receiver and satellite q Clock error; and Satellite q Ionospheric error and tropospheric delay error at time k+i when the signal propagates in the atmosphere; Indicates the phase wavelength of the carrier; represents the integer ambiguity of mobile station r in weeks; represents the observation noise of the carrier vector of mobile station r. It should be noted that the carrier phase equation of mobile station r is also the satellite observation data received by the pseudo reference station at time k+i (second time) in the present disclosure.

[0051] Subtracting (2) and (3) to achieve carrier single difference can eliminate the satellite clock error dt^((q)) and obtain the single difference model:

[0052] (4)

[0053] In formula (4), Represents the difference symbol, such as = - In the embodiment of the present disclosure, for a short baseline within 20 km, the tropospheric delay and ionospheric delay of the reference station and the mobile station are generally not much different, so it can be approximately considered that , , the atmospheric delay error term can be eliminated by difference, so equation (4) can be transformed into:

[0054] (5)

[0055] In the embodiment of the present disclosure, on the basis of the single difference of the carrier phase, in order to further eliminate the receiver clock error and eliminate the atmospheric delay error, it is considered to perform differential in the form of double difference of the carrier phase, that is, the receiver of the reference station b (pseudo reference station at time k) and the receiver of the mobile station r (pseudo reference station at time k+i) perform another inter-satellite differential on another reference satellite on the basis of the single difference. Assuming that satellite s is the reference satellite, the single difference of the reference station b and the mobile station r relative to the satellite s is similar to equation (5):

[0056] (6)

[0057] Differentiate equation (5) from equation (6) to eliminate the receiver clock error ,get:

[0058] (7)

[0059] In the formula, ∇Δ represents the double difference form, such as = - The receiver clock error is eliminated, which is conducive to the realization of RTK precise navigation and positioning.

[0060] In the embodiment of the present disclosure, the RTK precise positioning process can be described as follows: first read the pseudo-range and carrier phase observations of the base station and the mobile station. If the number of satellites is not less than 4, the basic single-point positioning is achieved by calculating the satellite position as the initial approximate position of the mobile station. The base station and the mobile station construct a single-difference observation model, select a satellite as a reference star, construct a double-difference observation, use the least squares method to solve the ambiguity floating-point solution, fix the ambiguity by the ambiguity fixing method, and finally correct the baseline to achieve RTK precise relative positioning. The following is a description of the specific process of solving the ambiguity floating-point solution, fixing the ambiguity by the ambiguity fixing method, and finally correcting the baseline to achieve RTK precise relative positioning in the present disclosure:

[0061] In the embodiment of the present disclosure, assuming that satellite s is used as a reference satellite, the calculation method of the ambiguity floating point solution is as follows:

[0062] (8)

[0063] In the formula, H represents the number of observed satellites; It represents the pseudorange double difference of the first satellite. In the embodiment of the present disclosure, the solution of the pseudorange double difference is the same as the solution of the carrier phase double difference, which will not be repeated here. represents the double difference of the carrier phase of the first satellite, Represents the three-dimensional direction vector from the reference station b (pseudo reference station at time k) to the reference satellite s; is the distance from the base station b (the pseudo base station at time k) to the satellite The three-dimensional direction vector of represents the three-dimensional position of the mobile station r (the pseudo reference station at time k+i) relative to the reference station b (the pseudo reference station at time k), represents the phase ambiguity.

[0064] In the embodiment of the present disclosure, the position coordinates at time k+i are directly calculated by the least squares algorithm for equation (9): and ambiguity float solution :

[0065] (9)

[0066] In formula (9), -1 The inverse matrix of the direction matrix in expression (8) is: -1 represents the system state covariance matrix, and are the pseudorange and carrier phase observation matrices in equation (8) respectively.

[0067] In the embodiment of the present disclosure, the corresponding covariance matrix is ​​also obtained by calculation:

[0068] (10)

[0069] In the formula, express The covariance matrix of yes The covariance matrix of , and the other parameters are the correlation relationship matrices between them.

[0070] In an embodiment of the present disclosure, a positioning system based on a track transponder is also provided, the system comprising: a transponder information receiving module, a satellite signal receiving module, a pseudo reference station module and a train control system.

[0071] A satellite signal receiving module, used for receiving satellite observation data at a first moment and a second moment;

[0072] A transponder information receiving module, used for receiving location information provided by the transponder;

[0073] The train control system is used to receive the position information provided by the transponder and transmit it to the pseudo reference station module;

[0074] The pseudo reference station module is used to determine the differential correction data of the satellite signal at the first moment based on the satellite observation data at the first moment and the position information provided by the transponder, and is also used to determine the real-time train positioning at the second moment based on the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment.

[0075] Figure 2 A schematic diagram of a positioning system based on a track transponder in an embodiment of the present disclosure is shown. Specifically, Figure 2 The system mainly includes the GNSS positioning module (satellite signal receiving module), pseudo reference station module, transponder module, transponder information receiving module and train control system carried by the train. The position and other information provided by the transponder are transmitted to the train control system through the transponder receiving module. The position and other information provided by the transponder are transmitted to the train control system through the transponder receiving module. At the same time, the GNSS receiver observes the satellite data. When the pseudo reference station module obtains the GNSS observation data at time k and the position information provided by the transponder, the differential correction data of the satellite signal at time k is calculated. , and the position data provided by the transponder at time K is used as the train position information. Realize RTK positioning with the GNSS observation data at time k+i, solve the position information of the train at time k+i, and realize high-precision positioning of the train from time k to time M. Repeat the above rules.

[0076] In the disclosed embodiment, when the interrogator on the train approaches the ground transponder, the transponder's coupling coil will sense the magnetic field of a specific frequency emitted by the interrogator. This magnetic field energy is converted into electrical energy by the energy receiving circuit in the transponder, thereby establishing the power supply required for the transponder to work. Once the power supply is established, the transponder starts to work, and determines whether it needs to send data through its internal control module. If the transponder receives a valid data request from the interrogator, it will send this data to the transponder information receiving module.

[0077] The transponder information receiving module establishes a close connection with the train control system by accurately capturing and decoding the data message sent by the ground transponder. Once the transponder signal is sensed, the position information and other key data in the transponder are received and processed. These data are transmitted to the train control system through the internal high-speed communication interface. According to the received position information, the safe speed curve of the train is calculated in real time, the train operation status is monitored, and the control strategy is adjusted to ensure that the train runs safely according to the predetermined path and speed. This process realizes the seamless connection between the transponder position information and the train control system, providing accurate and reliable positioning support for train operation.

[0078] The working principle of the GNSS receiver module is based on receiving signals from multiple satellites, calculating the signal propagation time, and using triangulation to calculate the three-dimensional position of the receiver, and finally transmitting it to the train control system through the network interface.

[0079] The function of the pseudo base station module is to receive the GNSS observation data and the position information provided by the transponder at a certain moment, and calculate the satellite signal differential correction data at that moment to prepare for the RTK positioning of the GNSS receiver module at a subsequent moment.

[0080] The main function of the train control system is to ensure the safe and efficient operation of trains on railway lines. The system integrates multiple modules, such as GNSS receiver module and transponder data receiving module, to achieve comprehensive monitoring and control of train operation.

[0081] Specifically, the pseudo reference station module includes a first submodule, a second submodule and a third submodule.

[0082] The first submodule is used to construct a single-difference observation model according to the pseudo-range and carrier phase observation data at the first moment and the second moment;

[0083] The second submodule is used to determine the reference satellite and construct a double difference observation model based on the reference satellite and the single difference observation model;

[0084] The third submodule is used to determine the real-time train position coordinates and ambiguity floating-point solution at the second moment according to the double-difference observation model.

[0085] The present disclosure also provides an electronic device, the electronic device comprising at least one processor and at least one memory, the memory being data-connected to the processor, wherein:

[0086] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the positioning method based on the track transponder described in the present disclosure.

[0087] The present disclosure also provides a computer storage medium storing one or more instructions, which, when executed by one or more computers, enable the one or more computers to implement the track transponder-based positioning method described in the present disclosure.

[0088] The positioning method, system, device and storage medium based on track transponders disclosed in the present invention can, on the one hand, effectively improve the train positioning accuracy between adjacent transponders, and on the other hand, realize the function of the base station in the RTK positioning technology by combining the known and high-precision position information of the transponder on the train track and the satellite observation data collected by the corresponding GNSS receiver module, effectively saving the construction and maintenance costs of the base station, and realizing continuous high-precision positioning of the train without building the base station in the RTK positioning technology. In an open environment, the satellite signal differential correction data at time K calculated by the pseudo-base station has a certain timeliness, which can realize high-precision positioning of trains within a certain distance, and reduce the laying density of transponders to the greatest extent, saving the cost of transponder construction and maintenance, reducing equipment construction and maintenance costs, and greatly saving system construction and maintenance costs; at the same time, because the GNSS receiver module and the transponder information receiving module can establish a reliable and stable communication mechanism with the train control system, there is no need to use a wireless network to establish a relationship between a base station and a mobile station like traditional RTK positioning technology, which significantly reduces communication delays and simplifies system equipment.

[0089] Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A positioning method based on a track transponder, characterized in that: The method comprises: Determining differential correction data of the satellite signal at the first moment according to the satellite observation data at the first moment and the position information provided by the transponder; Determining the real-time train positioning at the second moment according to the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment includes: constructing a single-difference observation model according to the pseudo-range and carrier phase observation data at the first moment and the second moment; determining a reference satellite, and constructing a double-difference observation model according to the reference satellite and the single-difference observation model; determining the real-time train position coordinates and ambiguity floating-point solution at the second moment according to the double-difference observation model; The train position information at the first moment is pseudo reference station position information, which is determined by the position information provided by the transponder at the first moment; the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment both include pseudo range and carrier phase observation data.

2. A positioning system based on a track transponder, characterized in that: The system includes: a transponder information receiving module, a satellite signal receiving module, a pseudo reference station module and a train control system. A satellite signal receiving module, used for receiving satellite observation data at a first moment and a second moment; A transponder information receiving module, used for receiving location information provided by the transponder; The train control system is used to receive the position information provided by the transponder and transmit it to the pseudo reference station module; A pseudo reference station module, used to determine the differential correction data of the satellite signal at the first moment according to the satellite observation data at the first moment and the position information provided by the transponder, and also used to determine the real-time train positioning at the second moment according to the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment; The train position information at the first moment is pseudo reference station position information, and the pseudo reference station position information is determined by the position information provided by the transponder at the first moment; the differential correction data of the satellite signal at the first moment and the satellite observation data at the second moment both include pseudo range and carrier phase observation data; The pseudo-reference station module includes a first submodule, a second submodule and a third submodule. The first submodule is used to construct a single-difference observation model based on pseudo-range and carrier phase observation data at the first moment and the second moment; the second submodule is used to determine a reference satellite and construct a double-difference observation model based on the reference satellite and the single-difference observation model; the third submodule is used to determine the real-time train position coordinates and ambiguity floating-point solution at the second moment based on the double-difference observation model.

3. An electronic device, comprising at least one processor and at least one memory, wherein the memory is data-connected to the processor, wherein: The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method of claim 1.

4. A computer storage medium, characterized in that: The computer storage medium stores one or more instructions that, when executed by one or more computers, cause the one or more computers to implement the method of claim 1 .

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