A train real-time continuous positioning system and method

Abstract

The present application discloses a real-time continuous positioning system and method for a train. The system obtains the sensor signal of the train by setting a fiber optic Bragg grating sensor cable on the track bed or in the track plate of the train, and converts the problem of continuous positioning of the train into the problem of signal data extraction for data processing of the sensor signal. Since the process of obtaining the sensor signal of the array fiber optic Bragg grating sensor cable is almost not interfered by the external environment, it can effectively adapt to the situation of poor wireless signal and ensure the reliability of the basic data of the sensor signal. Furthermore, by setting at least two array fiber optic Bragg grating sensor cables for data collection, the data redundancy is effectively improved, and the reliability of the train positioning result is improved.

Description

Technical Field

[0001] The present application relates to the technical field of train information management, and in particular to a real-time continuous positioning system and method for a train. Background Art

[0002] In the field of railway signaling, blocking means that after a train enters a section, the stations at both ends of the section will no longer send trains to this section to prevent train collisions and rear-end collisions. Real-time detection of train positions is the basis for achieving blocking control and the core of the train safety operation control system. Blocking methods can be divided into three types according to whether there are fixed block sections when detecting train positions: fixed blocking, quasi-mobile blocking, and mobile blocking.

[0003] At present, most railway transportation and urban rail transit are quasi-mobile block systems. The technology for train positioning and speed measurement is to measure the speed through the speed sensor installed on the train, and use the ground transponder to correct the position, and then use the ground-to-train wireless communication to detect the train position, speed, and train running direction. Because when obtaining the train positioning through the ground transponder, it is necessary not only to install more on-board sensors and on-board equipment on each train, but also to install a large number of trackside equipment along the line, and the requirements for the external environment are high, and it is overly dependent on the ground-to-train wireless communication that is susceptible to electromagnetic interference, resulting in low reliability of positioning results.

[0004] Therefore, in the prior art, in the process of real-time positioning of trains, there is a problem of low reliability of positioning results due to poor wireless signals. Summary of the invention

[0005] In view of this, it is necessary to provide a real-time continuous positioning system and method for a train to solve the problem of low reliability of positioning results due to poor wireless signals in the process of real-time positioning of trains in the prior art.

[0006] In order to solve the above problems, the present application provides a train real-time continuous positioning system, comprising:

[0007] At least two array fiber grating sensor cables, both of which are laid on the train track bed or buried in the track plate, and are used to obtain at least two sets of sensor signals of the train;

[0008] A demodulation module, used for demodulating at least two groups of sensor signals to obtain at least two groups of sensor signal data sequences;

[0009] The signal processing module is used to fuse at least two groups of sensor signal data sequences to obtain a fused sensor signal data sequence, and perform sequence detection on the fused sensor signal data sequence to determine the train positioning information.

[0010] Further, the two array fiber grating sensing optical cables at least include a main sensing optical cable and a spare sensing optical cable;

[0011] The demodulation module at least includes a first sub-demodulation module and a second sub-demodulation module;

[0012] The signal processing module at least includes a first sub-signal processing module and a second sub-signal processing module;

[0013] Among them, the main sensing optical cable and the backup sensing optical cable can back up each other;

[0014] The first sub-demodulation module is used to demodulate the first sensing signal data sequence acquired by the main sensing optical cable and input it to the first sub-signal processing module;

[0015] The second sub-demodulation module is used to demodulate the second sensing signal data sequence acquired by the spare sensing optical cable and input the data sequence to the second sub-signal processing module.

[0016] Further, it also includes a narrow bandwidth laser, an electro-optic modulator, a fiber amplifier, a first circulator, a second circulator and a Michelson interferometer;

[0017] Wherein, a narrow bandwidth laser is used to generate an initial optical signal;

[0018] The electro-optic modulator is used to modulate the initial optical signal to obtain a pulse optical signal;

[0019] The optical fiber amplifier is used to amplify the pulse light signal to obtain an amplified pulse light signal, and transmit the amplified pulse light signal to the array fiber grating sensor cable through the first circulator, and obtain the optical fiber pulse light signal after reflection and transmission by the array fiber grating sensor cable;

[0020] The optical fiber pulse light signal is transmitted to the Michelson interferometer via the second circulator, and the second circulator also outputs the first detection light signal;

[0021] The Michelson interferometer is used to perform interference processing on the optical fiber pulse light signal to obtain a second detection light signal.

[0022] Further, the Michelson interferometer includes a coupler, a first Faraday mirror, a second Faraday mirror and a delay optical fiber, and the length of the delay optical fiber is the same as the spacing of the array fiber grating;

[0023] The coupler couples the optical fiber pulse light signal to obtain a first optical fiber pulse light signal and a second optical fiber pulse light signal;

[0024] The first fiber optic pulse light signal passes through the first Faraday mirror to output a first interference detection light signal;

[0025] The second optical fiber pulse light signal passes through the delay optical fiber and then passes through the second Faraday mirror to output a second interference detection light signal.

[0026] Further, the demodulation module includes a first photodetector, a second photodetector, a first analog-to-digital converter, a second analog-to-digital converter, a first FPGA group, and a second FPGA group;

[0027] The first photodetector is used to perform photoelectric conversion on the first detection light signal and the first interference detection light signal to obtain a first original electrical signal and a second original electrical signal;

[0028] The second photoelectric detector is used to perform photoelectric conversion on the first detection light signal, the first interference detection light signal and the second interference detection light signal, and split them into two to obtain a first group of interference electrical signals and a second group of interference electrical signals;

[0029] The first FPGA group is used to perform analog-to-digital conversion on the first original electrical signal and the first group of interference electrical signals to obtain a first group of sensor signal data sequences;

[0030] The second FPGA group is used to perform analog-to-digital conversion on the second original electrical signal and the second group of interference electrical signals to obtain a second group of sensor signal data sequences;

[0031] Wherein, the first group of interference electrical signals and the second group of interference electrical signals each include three paths;

[0032] The first photodetector and the second photodetector may serve as backup for each other;

[0033] The first analog-to-digital converter and the second analog-to-digital converter may serve as backup for each other;

[0034] The first FPGA group and the second FPGA group can back up each other.

[0035] In order to solve the above problems, the present application also provides a method for real-time continuous positioning of a train, comprising:

[0036] Acquiring at least two sets of sensor signals of the train based on at least two array fiber grating sensor cables;

[0037] Demodulating at least two groups of sensor signals based on a demodulator to obtain at least two groups of sensor signal data sequences;

[0038] Based on the signal processing module, at least two groups of sensor signal data sequences are fused to obtain a fused sensor signal data sequence, and sequence detection is performed on the fused sensor signal data sequence to determine the train positioning information.

[0039] Furthermore, sequence detection is performed on the fused sensor signal data sequence, including:

[0040] The fused sensor signal data sequence is collected in real time at a preset time interval, and the RMS value of each signal segment is calculated;

[0041] Compare the RMS value with the preset RMS threshold to determine whether there is vibration in the measurement area corresponding to each signal segment;

[0042] When the RMS value is greater than the preset RMS threshold, it is determined that there is vibration in the measurement area, the measurement area is marked as an occupied measurement area, and a 1 is marked on the fusion sensor signal data sequence corresponding to the measurement area;

[0043] When the RMS value is not greater than the preset RMS threshold, it is determined that there is no vibration in the measurement area, the measurement area is marked as an unoccupied measurement area, and the fused sensor signal data sequence corresponding to the measurement area is marked as 0;

[0044] According to the sequence labeling result, the sequence detection result of the fused sensor signal data sequence is determined.

[0045] Further, according to the sequence labeling result, the sequence detection result of the fused sensor signal data sequence is determined, including:

[0046] Obtain the sensor data 0-1 sequence corresponding to the real-time sensor data sequence of each measurement area;

[0047] When the marked value in any sensor data 0-1 sequence changes, start recording the length of the data segment after the change;

[0048] Pre-set data segment length threshold;

[0049] When the length of the converted data segment is not less than the data segment length threshold, stop recording;

[0050] When the length of the transformed data segment is less than the data segment length threshold and transformation occurs again, the recording is stopped and the annotation value corresponding to the length of the transformed data segment is corrected to obtain a corrected sequence detection result.

[0051] Furthermore, the train positioning information includes whether there is a running train, the train position and vehicle integrity information; performing sequence detection on the fused sensor signal data sequence to determine the train positioning information includes:

[0052] According to the sequence detection result, determine whether there is an occupied measurement area;

[0053] When there is no occupied measurement area, it is determined that there is no running train;

[0054] When there is an occupied measurement area, it is determined that there is a running train, and the occupied measurement area position and the total number of occupied measurement areas corresponding to the occupied measurement area are obtained;

[0055] Determine the train position based on the occupied measurement area position;

[0056] Pre-set the number of standard measurement areas;

[0057] Compare the total number of occupied measurement areas with the number of standard measurement areas to determine the vehicle integrity information.

[0058] Furthermore, the train positioning information also includes the running direction and the running speed; performing sequence detection on the fused sensor signal data sequence to determine the train positioning information also includes:

[0059] Obtain the sequence test results of the entire line and the entire test area;

[0060] When the sequence detection result of a single measurement area changes from 0 to 1 / from 1 to 0, it is marked as the train occupying / releasing the measurement area;

[0061] Obtain the sequence detection transformation result of the adjacent measurement area after the transformation moment, and record the interval data sequence length after which the fusion sensor signal data sequence transformation is completed;

[0062] Compare the changing trends of the sequence test results of adjacent measurement areas to determine the running direction;

[0063] Get the measurement area length and sampling time interval;

[0064] Determine the running speed based on the measurement area length, sampling time interval and interval data sequence length

[0065] The beneficial effects of the present application are as follows: the present application provides a real-time continuous positioning system and method for a train, which obtains the sensor signal of the train by setting a fiber optic Bragg grating sensor cable on the train track bed or in the track plate, and converts the problem of continuous positioning of the train into a signal data extraction problem for data processing of the sensor signal; since the process of obtaining the sensor signal of the array fiber optic Bragg grating sensor cable is almost not affected by the external environment, it can effectively adapt to the situation of poor wireless signal and ensure the reliability of the basic data of the sensor signal; further, by setting at least two array fiber optic Bragg grating sensor cables for data collection, the data redundancy is effectively improved, and the reliability of the train positioning result is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 A schematic diagram of the structure of the first embodiment of the real-time continuous positioning system for trains provided in this application;

[0067] Figure 2 A schematic diagram of the structure of the second embodiment of the real-time continuous positioning system for trains provided in this application;

[0068] Figure 3 A schematic diagram of the structure of an embodiment of a demodulation module provided by the present application;

[0069] Figure 4A schematic diagram of a flow chart of an embodiment of a method for real-time continuous positioning of a train provided by the present invention;

[0070] Figure 5 A schematic diagram of a flow chart of an embodiment of performing sequence detection on a fused sensor signal data sequence provided by the present invention;

[0071] Figure 6 A schematic diagram of a flow chart of an embodiment of correcting sequence annotation results provided by the present invention;

[0072] Figure 7 A schematic diagram of a flow chart of a first embodiment of determining train location information provided by the present invention;

[0073] Figure 8 A schematic diagram of the flow chart of the second embodiment of determining train location information provided by the present invention. DETAILED DESCRIPTION

[0074] The preferred embodiments of the present application are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present application and are used together with the embodiments of the present application to illustrate the principles of the present application, and are not used to limit the scope of the present application.

[0075] In the field of railway signaling, blocking means that after a train enters a section, the stations at both ends of the section will no longer send trains to this section to prevent train collisions and rear-end collisions. Real-time detection of train positions is the basis for achieving blocking control and the core of the train safety operation control system. Blocking methods can be divided into three types according to whether there are fixed block sections when detecting train positions: fixed blocking, quasi-mobile blocking, and mobile blocking.

[0076] In the early days, fixed block railways were used, and track circuit technology was used to detect the section where the train was located. The track circuit divided the section between two stations into several block sections, and only one train was allowed to run in each block section. The track circuit technology has a long section length for train positioning (about several kilometers to tens of kilometers), and the train travel efficiency is low, which now does not meet the requirements of urban rail transit development.

[0077] At present, most railway transportation and urban rail transit are quasi-mobile block systems. The technology for train positioning and speed measurement is to measure the speed through the speed sensor installed on the train, and use the ground transponder to perform position correction, and then realize the train position detection, speed detection, and train running direction determination through the train-ground wireless communication. It has the following shortcomings: (1) The ground transponder still only detects the train's occupied interval. The specific position of the train in this interval is indirectly obtained by calculating the train speedometer, and the positioning error is large; (2) It does not have the ability to detect vehicle integrity, and it is necessary to install a special axle counting device on the trackside to assist in completing the vehicle integrity detection; (3) The system is complex, not only requiring the installation of more on-board sensors and on-board equipment on each train, but also requiring the installation of a large number of trackside equipment along the line, and over-reliance on the train-ground wireless communication that is susceptible to electromagnetic interference. Therefore, when the key equipment and communication links fail, the system is downgraded to automatic station-to-station blocking, and only one train is allowed to run between two adjacent stations, which has a great impact on transportation capacity.

[0078] Therefore, in the prior art, in the process of acquiring train operation data in real time, there is a problem that the accuracy of the train operation data is not high due to poor wireless signals.

[0079] In order to solve the above problems, the present application provides a train real-time continuous positioning system and method, which are described in detail below.

[0080] like Figure 1 As shown, Figure 1 This is a schematic diagram of the structure of the first embodiment of the real-time continuous positioning system for trains provided in the present application. The real-time continuous positioning system for trains includes:

[0081] At least two array fiber grating sensor cables (11 and 12), both of which are laid on the train track bed or in the track plate, and are used to obtain at least two sets of sensor signals of the train;

[0082] A demodulation module 20, used to demodulate at least two groups of sensor signals to obtain at least two groups of sensor signal data sequences;

[0083] The signal processing module 30 is used to fuse at least two sets of sensor signal data sequences to obtain a fused sensor signal data sequence, and perform sequence detection on the fused sensor signal data sequence to determine the train positioning information.

[0084] In this embodiment, by setting at least two array fiber grating sensor cables (11 and 12) on the train track bed or in the track plate, at least two groups of sensor signals of the train can be acquired in real time; based on the demodulation module 20, at least two groups of sensor signals are demodulated in real time to obtain at least two groups of sensor signal data sequences; finally, the signal processing module 30 fuses the at least two groups of sensor signal data sequences to obtain a fused sensor signal data sequence with higher reliability, and the train positioning information is determined by performing sequence detection on the fused sensor signal data sequence.

[0085] In this embodiment, the continuous positioning problem of the train is converted into a signal data extraction problem for processing the sensor signals of the array fiber grating sensor cables (11 and 12) laid on the train track bed or buried in the track plate. Since the process of obtaining the sensor signals of the array fiber grating sensor cables (11 and 12) is almost not affected by the external environment, it can effectively adapt to the situation of poor wireless signals and ensure the reliability of the basic data of the sensor signals. Furthermore, since the force on both sides of the train is uneven during operation, at least two array fiber grating sensor cables (11 and 12) are provided to obtain the sensor signals of the train, so as to improve the reliability of the train positioning results by improving the redundancy of the train positioning data.

[0086] As a preferred embodiment, at least two array fiber grating sensor cables (11 and 12) include at least a main sensor cable and a backup sensor cable. Both the main sensor cable and the backup sensor cable can independently realize real-time perception of the train running status, and the main sensor cable and the backup sensor cable can back up each other.

[0087] Among them, in order to improve the comprehensiveness of the acquired data, the main sensor optical cable and the backup sensor optical cable are respectively arranged on the track bed or in the track plate on the left and right sides of the train, so as to realize the monitoring of the sensor signals on the left side of the train and the right side of the train, and to amplify the subtle differences between the sensor signals as much as possible.

[0088] In a specific embodiment, in order to improve the reliability of the array fiber Bragg grating sensor cable and avoid damage to the array fiber Bragg grating sensor cable due to changes in the external environment during use, the array fiber Bragg grating sensor cable is buried on the train track bed when the track plate is cast, or the array fiber Bragg grating sensor cable is buried in a reserved groove of the track plate. In addition, the sensing signal includes a vibration signal or a strain signal.

[0089] In other embodiments, the position of the array fiber grating sensor cable may be set in other ways. The sensor signal may also exist in other forms of signals.

[0090] Further, the demodulation module at least includes a first sub-demodulation module and a second sub-demodulation module, and the signal processing module at least includes a first sub-signal processing module and a second sub-signal processing module;

[0091] Among them, the first sub-demodulation module is used to demodulate the first sensor signal data sequence obtained by the main sensor optical cable and input it to the first sub-signal processing module; the second sub-demodulation module is used to demodulate the second sensor signal data sequence obtained by the backup sensor optical cable and input it to the second sub-signal processing module.

[0092] In this embodiment, by configuring the main sensing optical cable and the backup sensing optical cable with independent demodulation modules and signal processing modules, any array fiber Bragg grating sensing optical cable can be used as the main and backup optical cables. By processing multiple sets of data corresponding to multiple array fiber Bragg grating sensing optical cables of the train, the redundancy of data processing is effectively improved, so that the subtle details can be magnified to facilitate timely detection of problems, and the reliability of data is improved, thereby improving the reliability of positioning results.

[0093] In a specific embodiment, within a communication cycle, if one array fiber grating sensor cable is determined as the main sensor cable, the remaining array fiber grating sensor cables are automatically determined as backup sensor cables to improve system redundancy. It should be noted that the main and backup sensor cables can be switched in real time, that is, all array fiber grating sensor cable channels are backups for each other.

[0094] In a specific embodiment, on the basis of setting up two array fiber grating sensor cables (11 and 12), a third array fiber grating sensor cable or even more array fiber grating sensor cables can be set to obtain the sensor signal of the train to improve the reliability of the positioning result.

[0095] In a specific embodiment, since the train operation time interval is relatively stable, in order to improve the reliability of the main sensor optical cable, the communication time between the main sensor optical cable and the signal processing module 30 is also controlled. When the signal processing module 30 does not receive the sensor signal data of the main sensor optical cable within the timeout threshold, it is determined that the main sensor optical cable has failed, and the main sensor optical cable is replaced in real time, switching to the spare sensor optical cable for data analysis and processing.

[0096] As a preferred embodiment, in order to explain in detail the process of obtaining the sensor signal of the train based on the real-time continuous positioning system of the train, as shown in FIG. Figure 2 As shown, Figure 2 This is a schematic diagram of the structure of the second embodiment of the real-time continuous positioning system for trains provided in the present application. The real-time continuous positioning system for trains further includes a narrow bandwidth laser 40, an electro-optic modulator 50, an optical fiber amplifier 60, a first circulator 70, a second circulator 80 and a Michelson interferometer 90;

[0097] Wherein, the first circulator includes a first port a, a second port b and a third port c, and the second circulator includes a fourth port d, a fifth port e and a sixth port f;

[0098] The first port a is connected to the optical fiber amplifier 60, the second port b is connected to the array fiber grating sensor cable, the third port c is connected to the fourth port d, and the fifth port e is connected to the Michelson interferometer 90;

[0099] The narrow bandwidth laser 40 is used to generate an initial optical signal;

[0100] The electro-optic modulator 50 is used to modulate the initial optical signal to obtain a pulse optical signal;

[0101] The optical fiber amplifier 60 is used to amplify the pulse light signal to obtain an amplified pulse light signal, and transmit the amplified pulse light signal to the array fiber grating sensor cable through the first circulator 70, and obtain the optical fiber pulse light signal after reflection and transmission of the array fiber grating sensor cable;

[0102] It should be noted that the amplified pulse light signal enters from the first port a, exits from the second port b, and enters the array fiber grating sensor cable; after reflection and transmission by the array fiber grating sensor cable, a fiber pulse light signal is obtained, and the fiber pulse light signal enters from the second port b, exits from the third port c, and enters the second circulator 80;

[0103] The fiber optic pulse light signal enters from the fourth port d and exits from the sixth port f to obtain a first detection light signal; the fiber optic pulse light signal enters from the fourth port d and exits from the fifth port e to enter the Michelson interferometer 90;

[0104] The Michelson interferometer 90 is used to perform interference processing on the optical fiber pulse light signal to obtain a second detection light signal.

[0105] In this embodiment, the fiber optic pulse light signal is split into two by the second circulator 80, not only obtaining the first detection light signal as a comparison standard, but also performing interference processing on the fiber optic pulse light signal by the Michelson interferometer 90 to obtain the second detection light signal, thereby realizing the determination of the train's sensor signal by the first detection light signal and the second detection light signal, thereby ensuring the reliability of the sensor signal.

[0106] As a preferred embodiment, the Michelson interferometer 90 includes a coupler 91, a first Faraday mirror 92, a second Faraday mirror 93 and a delay optical fiber 94, and the length of the delay optical fiber 94 is the same as the spacing of the array fiber grating;

[0107] Wherein, the second detection light signal includes a first interference detection light signal and a second interference detection light signal;

[0108] The coupler 91 includes a seventh port g, an eighth port h and i;

[0109] And the seventh port g is connected to the fifth port e.

[0110] In the process of processing the second detection light signal, the coupler 91 couples the optical fiber pulse light signal to obtain the first optical fiber pulse light signal and the second optical fiber pulse light signal;

[0111] The first fiber pulse light signal passes through the first Faraday mirror 92, and outputs a first interference detection light signal from the eighth port h;

[0112] The second fiber optic pulse light signal passes through the delay fiber 94 and then passes through the second Faraday mirror 93, and then outputs the second interference detection light signal from i.

[0113] In this embodiment, the second detection light signal is split into two by a coupler 91, and is processed by a first Faraday mirror 92, a second Faraday mirror 93 and a delay optical fiber 94 respectively, to obtain a first interference detection light signal and a second interference detection light signal, thereby increasing the number of interference light signals and improving data redundancy and reliability.

[0114] As a preferred embodiment, in order to demodulate the sensing signal, Figure 3 As shown, Figure 3 This is a schematic diagram of the structure of an embodiment of a demodulation module provided in the present application. The demodulation module 20 includes a first photodetector 21, a second photodetector 22, a first analog-to-digital converter 23, a second analog-to-digital converter 24, a first FPGA group 25, and a second FPGA group 26;

[0115] Wherein, the first photodetector 21 is connected to the sixth port f and the eighth port h respectively;

[0116] The second photodetector 22 is connected to the sixth port f, the eighth port h and i respectively;

[0117] The first analog-to-digital converter 23 is connected to the first photodetector 21 and the first FPGA group 25 respectively;

[0118] The second analog-to-digital converter 24 is connected to the second photodetector 22 and the second FPGA group 26 respectively.

[0119] The first photodetector 21 is used to perform photoelectric conversion on the first detection light signal and the first interference detection light signal to obtain a first original electrical signal and a second original electrical signal;

[0120] The second photodetector 22 is used to perform photoelectric conversion on the first detection light signal, the first interference detection light signal and the second interference detection light signal, and perform two-way processing to obtain a first group of interference electrical signals and a second group of interference electrical signals;

[0121] The first FPGA group 25 is used to perform analog-to-digital conversion on the first original electrical signal and the first group of interference electrical signals to obtain a first group of sensor signal data sequences;

[0122] The second FPGA group 26 is used to perform analog-to-digital conversion on the second original electrical signal and the second group of interference electrical signals to obtain a second group of sensor signal data sequence;

[0123] Wherein, the first group of interference electrical signals and the second group of interference electrical signals each include three paths;

[0124] The first photodetector 21 and the second photodetector 22 can serve as backup for each other;

[0125] The first analog-to-digital converter 23 and the second analog-to-digital converter 24 can serve as backup for each other;

[0126] The first FPGA group 25 and the second FPGA group 26 can back up each other.

[0127] In this embodiment, the first detection light signal and the first interference detection light signal are used as a signal group for photoelectric conversion, and finally a first group of sensor signal data sequences are obtained as a reference standard, thereby eliminating the influence of the circulator and the coupler itself on the final sensor signal data sequence; the second photodetector 22 is used to perform one-to-two processing to achieve one-to-two output, thereby improving data redundancy, and by comparing and fusing the one-to-two output signals, the reliability of the data is improved.

[0128] It should be noted that, in this embodiment, when only the first photodetector 21, the first analog-to-digital converter 23 and the first FPGA group 25 can operate normally, the sensor signal of the train can still be obtained, and the entire system still includes a complete loop.

[0129] That is, when extreme situations occur, the first photodetector 21 and the second photodetector 22 can back up each other. When only one of the photodetectors can operate normally, the photoelectric signal conversion can still be realized and transmitted to the first analog-to-digital converter 23 and the second analog-to-digital converter 24; the first analog-to-digital converter 23 and the second analog-to-digital converter 24 can back up each other; the first FPGA group 25 corresponds to the first analog-to-digital converter 23, and can realize analog-to-digital conversion to obtain a first group of sensor signal data sequences; the second FPGA group 26 corresponds to the second analog-to-digital converter 24, and can realize analog-to-digital conversion to obtain a second group of sensor signal data sequences.

[0130] In other words, as long as there are photoelectric detectors, analog-to-digital converters and their corresponding FPGA groups that can operate normally, it is possible to obtain the sensor signals of the train.

[0131] In order to solve the above problems, the present application also provides a method for real-time continuous positioning of trains, such as Figure 4 As shown, Figure 4 A flow chart of an embodiment of a method for real-time continuous positioning of a train provided by the present invention includes:

[0132] Step S101: acquiring at least two groups of sensor signals of a train based on at least two array fiber grating sensor cables;

[0133] Step S102: demodulating the at least two groups of sensor signals based on a demodulator to obtain at least two groups of sensor signal data sequences;

[0134] Step S103: Based on the signal processing module, the at least two groups of sensor signal data sequences are fused to obtain a fused sensor signal data sequence, and sequence detection is performed on the fused sensor signal data sequence to determine the train positioning information.

[0135] In this embodiment, first, at least two groups of sensor signals of the train are acquired based on at least two array fiber grating sensor cables; next, the at least two groups of sensor signals are demodulated based on a demodulator to obtain at least two groups of sensor signal data sequences; finally, the at least two groups of sensor signal data sequences are fused based on a signal processing module to obtain a fused sensor signal data sequence, and sequence detection is performed on the fused sensor signal data sequence to determine the train positioning information.

[0136] In this embodiment, the sensor signal of the train is obtained by setting a fiber optic Bragg grating sensor cable on the train track bed or in the track plate, and the continuous positioning problem of the train is converted into a signal data extraction problem for data processing of the sensor signal; since the process of obtaining the sensor signal of the array fiber optic Bragg grating sensor cable is almost not affected by the external environment, it can effectively adapt to the situation of poor wireless signal and ensure the reliability of the basic data of the sensor signal; further, by setting at least two array fiber optic Bragg grating sensor cables for data collection, the data redundancy is effectively improved, and the reliability of the train positioning result is improved.

[0137] As a preferred embodiment, in step S103, in order to perform sequence detection on the fused sensor signal data sequence, as Figure 5 As shown, Figure 5 The schematic diagram of a flow chart of an embodiment of performing sequence detection on a fused sensor signal data sequence provided by the present invention includes:

[0138] Step S131: collecting the fused sensor signal data sequence in real time at a preset time interval, and calculating the RMS value of each signal segment;

[0139] Step S132: comparing the RMS value with a preset RMS threshold value to determine whether vibration exists in the measurement area corresponding to each signal segment;

[0140] Step S133: when the RMS value is greater than the preset RMS threshold, it is determined that there is vibration in the measurement area, the measurement area is marked as an occupied measurement area, and a 1 is marked on the fused sensor signal data sequence corresponding to the measurement area;

[0141] Step S134: when the RMS value is not greater than the preset RMS threshold, it is determined that there is no vibration in the measurement area, the measurement area is marked as an unoccupied measurement area, and a 0 is marked on the fused sensor signal data sequence corresponding to the measurement area;

[0142] Step S135: Determine the sequence detection result of the fused sensor signal data sequence according to the sequence labeling result.

[0143] In this embodiment, first, the acquired fusion sensor signal data sequence is collected in real time according to a preset time interval to determine the RMS value of each corresponding signal segment; then, based on the preset RMS threshold, the RMS value of each signal segment is refined to determine the train operation status corresponding to each preset time interval; judging whether there is vibration by the RMS value of the signal segment can better judge whether there is data with large changes in the fusion sensor signal data sequence, thereby ensuring the reliability of the vibration judgment result; in addition, since the preset time interval is very short, the corresponding measurement area distance is also very short, and the length of the train itself is relatively long, it is possible to achieve real-time determination of the train positioning.

[0144] Furthermore, since only the wheel-rail contacts the ground track during the train's movement to generate vibration signals, the carriage part between the two sets of wheel-rails does not directly contact the fiber Bragg grating when entering the measurement area, so no vibration signal will be recorded by the sensor. In order to further make the sequence detection results close to the actual train operation and improve the accuracy and reliability of the sequence detection results, in step S135, after obtaining the sequence labeling results, it is necessary to correct the sequence labeling results to determine the sequence detection results, such as Figure 6 As shown, Figure 6 A schematic diagram of a process for correcting sequence annotation results according to an embodiment of the present invention includes:

[0145] Step S1351: Acquire the sensor data 0-1 sequence corresponding to the real-time sensor data sequence of each measurement area;

[0146] Step S1352: when the marked value in any sensor data 0-1 sequence changes, start recording the length of the data segment after the change;

[0147] Step S1353: pre-set a data segment length threshold;

[0148] Step S1354: when the length of the converted data segment is not less than the data segment length threshold, stop recording;

[0149] Step S1355: When the length of the transformed data segment is less than the data segment length threshold and transformation occurs again, stop recording and correct the annotation value corresponding to the length of the transformed data segment to obtain a corrected sequence detection result.

[0150] In this implementation, in order to avoid the subsequent positioning errors caused by the failure of the wheel-less rail carriage to generate effective vibration signals, after reading the sensor data sequence output in real time from each measurement area, the data segment length threshold is set to timely filter out invalid vibration data and correct the sequence annotation results that have changed.

[0151] As a preferred embodiment, the train positioning information includes whether there is a running train, the train position and the vehicle integrity information. In order to perform sequence detection on the fused sensor signal data sequence to determine the train positioning information, such as Figure 7 As shown, Figure 7 A schematic diagram of a flow chart of a first embodiment of determining train location information provided by the present invention includes:

[0152] Step S231: Determine whether there is an occupied measurement area according to the sequence detection result;

[0153] Step S232: when there is no occupied measurement area, it is determined that there is no running train;

[0154] Step S233: when there is an occupied measurement area, it is determined that there is a running train, and the occupied measurement area position and the total number of occupied measurement areas corresponding to the occupied measurement area are obtained;

[0155] Step S234: determining the train position according to the occupied measurement area position;

[0156] Step S235: presetting the number of standard measurement areas;

[0157] Step S236: Compare the total number of measurement areas occupied with the number of standard measurement areas to determine vehicle integrity information.

[0158] It should be noted that, in step S231, the sequence detection result is in the form of "00011...1100" which only contains the numbers "0" and "1", wherein the number "0" represents that there is no effective vibration in the corresponding measurement area, and the number "1" represents that there is effective vibration in the corresponding measurement area, that is, there is a running train in the measurement area.

[0159] In this embodiment, since each sequence detection result "0" or "1" has its corresponding measurement area, and the location of the measurement area is a known quantity, it is possible to quickly determine whether there is no running train in the measurement area and the train position based on the sequence detection result; and because each sequence detection result "0" or "1" corresponds to a measurement area, and the length of each measurement area is the same, it is possible to quickly determine the number of measurement areas with effective vibration based on the sequence detection result, and determine whether the length of the current train meets the requirements based on the standard number of measurement areas, that is, determine whether the vehicle remains intact.

[0160] As a preferred embodiment, the train positioning information also includes the running direction and the running speed. In order to perform sequence detection on the fused sensor signal data sequence to determine the train positioning information, such as Figure 8 As shown, Figure 8 A schematic diagram of a flow chart of a second embodiment of determining train location information provided by the present invention includes:

[0161] Step S331: Obtaining sequence detection results for the entire line and the entire test area;

[0162] Step S332: when the sequence detection result of a single measurement area changes from 0 to 1 / from 1 to 0, it is marked as the train occupying / releasing the occupation of the measurement area;

[0163] Step S333: obtaining the sequence detection transformation result of the adjacent measurement area after the transformation moment, and recording the length of the interval data sequence after which the fused sensing signal data sequence transformation is completed;

[0164] Step S334: comparing the change trends of the sequence detection results of adjacent measurement areas to determine the running direction;

[0165] Step S335: Obtain the measurement area length and sampling time interval;

[0166] Step S336: Determine the running speed according to the measurement area length, sampling time interval and interval data sequence length.

[0167] In this embodiment, when a single measurement area sequence changes from 0 to 1 / from 1 to 0, it indicates that the current train occupies or releases the measurement area. Based on this, in order to determine the running direction of the train, the change trends of the sequence detection results of adjacent measurement areas are compared. When the sequence detection result changes from "0011...10000" to "0000011...10", it indicates that the current train is moving away from the first circulator, otherwise, it is moving towards the first circulator.

[0168] Furthermore, based on the principle that the sampling time interval of each data sequence remains unchanged and the measurement area length remains unchanged, after obtaining the length of the interval data sequence that changes within the sampling time interval, the running speed is determined according to the measurement area length, the sampling time interval and the interval data sequence length.

[0169] In this embodiment, by reading the real-time sensor data sequence of the entire measurement area and integrating the real-time sensor data sequence matrix of the entire measurement area, real-time estimation and calculation of the train speed and running direction are realized in the time and space range, avoiding the problem that the existing technology only relies on the on-board speed sensor and the on-board communication system to periodically send data, position and other information and cannot realize continuous calculation and update, and there are blind spots and communication interference in the communication environment without a transponder.

[0170] Through the above technical scheme, the sensor signal of the train is obtained by setting a fiber optic Bragg grating sensor cable on the train track bed or in the track plate, and the continuous positioning problem of the train is converted into a signal data extraction problem for data processing of the sensor signal; because the process of obtaining the sensor signal of the array fiber optic Bragg grating sensor cable is almost not affected by the external environment, it can effectively adapt to the situation of poor wireless signal and ensure the reliability of the basic data of the sensor signal; further, by setting at least two array fiber optic Bragg grating sensor cables for data collection, the data redundancy is effectively improved, and the reliability of the train positioning result is improved.

[0171] The vibration of the train is sensed by setting a fiber optic Bragg grating sensor cable, which is a direct, single-type sensor with a highly consistent positioning mode, which innovates the existing train positioning mode of jointly estimating the positioning through a speed sensor and a transponder; and, the vibration signal of the train is obtained by setting a fiber optic Bragg grating sensor cable, which is a wired communication method, avoiding various communication interferences existing in the train-to-ground wireless communication in the prior art, especially the instability of wireless communication under thunderstorm weather conditions; further, since the time interval for obtaining the sensor signal of the train through the fiber optic Bragg grating sensor cable is very short, it is possible to obtain the positioning information of the train in real time and continuously.

[0172] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A real-time continuous train positioning system, characterized in that: include: At least two array fiber grating sensor cables, which are laid on the train track bed or buried in the track plate and are used to obtain at least two sets of sensor signals of the train; A demodulation module, used for demodulating the at least two groups of sensor signals to obtain at least two groups of sensor signal data sequences; A signal processing module, used for fusing the at least two sets of sensor signal data sequences to obtain a fused sensor signal data sequence, and performing sequence detection on the fused sensor signal data sequence to determine train positioning information; A narrow bandwidth laser, an electro-optic modulator, a fiber amplifier, a first circulator, a second circulator, and a Michelson interferometer; Wherein, the narrow bandwidth laser is used to generate an initial optical signal; The electro-optic modulator is used to modulate the initial optical signal to obtain a pulse optical signal; The optical fiber amplifier is used to amplify the pulse light signal to obtain an amplified pulse light signal, and transmit the amplified pulse light signal to the array fiber grating sensor cable via the first circulator, and obtain an optical fiber pulse light signal after reflection and transmission by the array fiber grating sensor cable; The optical fiber pulse light signal is transmitted to the Michelson interferometer via the second circulator, and the second circulator also outputs a first detection light signal; The Michelson interferometer is used to perform interference processing on the optical fiber pulse light signal to obtain a second detection light signal; Specifically, the Michelson interferometer includes a coupler, a first Faraday mirror, a second Faraday mirror and a delay optical fiber, and the length of the delay optical fiber is the same as the spacing of the array fiber grating; The coupler couples the optical fiber pulse light signal to obtain a first optical fiber pulse light signal and a second optical fiber pulse light signal; The first optical fiber pulse light signal passes through the first Faraday mirror to output a first interference detection light signal; After the second optical fiber pulse light signal passes through the delay optical fiber, it passes through the second Faraday mirror to output a second interference detection light signal; In addition, the demodulation module includes a first photodetector, a second photodetector, a first analog-to-digital converter, a second analog-to-digital converter, a first FPGA group, and a second FPGA group; The first photodetector is used to perform photoelectric conversion on the first detection light signal and the first interference detection light signal to obtain a first original electrical signal and a second original electrical signal; The second photodetector is used to perform photoelectric conversion on the first detection light signal, the first interference detection light signal and the second interference detection light signal, and split them into two to obtain a first group of interference electrical signals and a second group of interference electrical signals; The first FPGA group is used to perform analog-to-digital conversion on the first original electrical signal and the first group of interference electrical signals to obtain a first group of sensor signal data sequences; The second FPGA group is used to perform analog-to-digital conversion on the second original electrical signal and the second group of interference electrical signals to obtain a second group of sensor signal data sequences.

2. The train real-time continuous positioning system according to claim 1, characterized in that: The two array fiber grating sensing optical cables at least include a main sensing optical cable and a spare sensing optical cable; The demodulation module at least includes a first sub-demodulation module and a second sub-demodulation module; The signal processing module at least includes a first sub-signal processing module and a second sub-signal processing module; Wherein, the main sensing optical cable and the backup sensing optical cable can serve as backup for each other; The first sub-demodulation module is used to demodulate the first sensing signal data sequence acquired by the main sensing optical cable and input it to the first sub-signal processing module; The second sub-demodulation module is used to demodulate the second sensing signal data sequence acquired by the spare sensing optical cable and input the data sequence to the second sub-signal processing module.

3. The train real-time continuous positioning system according to claim 1, characterized in that: The first group of interference electrical signals and the second group of interference electrical signals each include three paths The first photodetector and the second photodetector may serve as backup for each other; The first analog-to-digital converter and the second analog-to-digital converter may serve as backup for each other; The first FPGA group and the second FPGA group can back up each other.

4. A method for real-time continuous positioning of a train, characterized in that: The method is applied to the train real-time continuous positioning system according to any one of claims 1 to 3, and the method comprises: Acquiring at least two sets of sensor signals of the train based on at least two array fiber grating sensor cables; Demodulating the at least two groups of sensor signals based on a demodulator to obtain at least two groups of sensor signal data sequences; Based on the signal processing module, the at least two groups of sensor signal data sequences are fused to obtain a fused sensor signal data sequence, and sequence detection is performed on the fused sensor signal data sequence to determine the train positioning information; The step of performing sequence detection on the fused sensor signal data sequence includes: The fused sensor signal data sequence is collected in real time at a preset time interval, and the RMS value of each signal segment is calculated; Comparing the RMS value with a preset RMS threshold value, and determining whether there is vibration in the measurement area corresponding to each of the signal segments; When the RMS value is greater than the preset RMS threshold, it is determined that vibration exists in the measurement area, the measurement area is marked as an occupied measurement area, and a 1 is marked on the fused sensor signal data sequence corresponding to the measurement area; When the RMS value is not greater than the preset RMS threshold, it is determined that there is no vibration in the measurement area, the measurement area is marked as an unoccupied measurement area, and a 0 is marked on the fused sensor signal data sequence corresponding to the measurement area; Determining a sequence detection result of the fused sensor signal data sequence according to the sequence labeling result; The train positioning information includes whether there is a running train, the train position and vehicle integrity information; performing sequence detection on the fused sensor signal data sequence to determine the train positioning information includes: Determining whether the occupied measurement area exists according to the sequence detection result; When the occupied measurement area does not exist, it is determined that there is no running train; When the occupied measurement area exists, it is determined that there is a running train, and the occupied measurement area position and the total number of occupied measurement areas corresponding to the occupied measurement area are obtained; Determining the train position according to the occupied measurement area position; Pre-set the number of standard measurement areas; The total number of occupied measurement areas is compared with the standard number of measurement areas to determine the vehicle integrity information.

5. The method for real-time continuous positioning of a train according to claim 4, characterized in that: The step of determining the sequence detection result of the fused sensor signal data sequence according to the sequence labeling result includes: Acquire a sensor data 0-1 sequence corresponding to the real-time sensor data sequence of each measurement area; When any of the labeled values ​​in the sensor data 0-1 sequence changes, start recording the length of the data segment after the change; Pre-set data segment length threshold; When the length of the converted data segment is not less than the data segment length threshold, stop recording; When the length of the transformed data segment is less than the data segment length threshold and transformation occurs again, the recording is stopped and the marked value corresponding to the length of the transformed data segment is corrected to obtain a corrected sequence detection result.

6. The method for real-time continuous positioning of a train according to claim 4, characterized in that: The train positioning information also includes the running direction and the running speed; performing sequence detection on the fused sensor signal data sequence to determine the train positioning information also includes: Obtain the sequence detection results of the entire line and the entire test area; When the sequence detection result of a single measurement area changes from 0 to 1 / from 1 to 0, it is marked as the train occupying / releasing the measurement area; Obtaining sequence detection transformation results of adjacent measurement areas after the transformation occurs, and recording the length of the interval data sequence through which the transformation of the fused sensor signal data sequence is completed; Comparing the change trends of the sequence detection results of the adjacent measurement areas to determine the running direction; Get the measurement area length and sampling time interval; The running speed is determined according to the measuring area length, the sampling time interval and the interval data sequence length.

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