CN116691784A - Real-time continuous positioning system and method for train - Google Patents

Abstract

The application discloses a real-time continuous positioning system and a real-time continuous positioning method for a train, wherein the system acquires a sensing signal of the train by arranging a fiber grating sensing optical cable on a railway track bed or in a railway plate of the train, and converts the continuous positioning problem of the train into a signal data extraction problem for carrying out data processing on the sensing signal; the process of acquiring the sensing signal of the array fiber bragg grating sensing optical cable is hardly interfered by the external environment, so that the method can effectively adapt to the condition of poor wireless signals and ensure the reliability of the basic data of the sensing signal; further, data acquisition is carried out by arranging at least two array fiber bragg grating sensing optical cables, so that the data redundancy is effectively improved, and the reliability of a train positioning result is improved.

Description

Real-time continuous positioning system and method for train

Technical Field

The application relates to the technical field of train information management, in particular to a train real-time continuous positioning system and method.

Background

In the railway signal field, the blocking means that after a train enters a section, stations at two ends of the section do not send out a train to the section any more so as to prevent the train from collision and rear-end collision. The real-time detection of the train position is the basis for realizing the blocking control and is the core of a train safe operation control system. The blocking method can be divided into three types according to whether there is a fixed partition in the train position detection: fixed occlusion, quasi-mobile occlusion, mobile occlusion.

Currently, railway transportation and urban rail transportation are currently mostly quasi-mobile occlusion systems. The technology for positioning and measuring the speed of the train is to measure the speed by a speed sensor arranged on the train, correct the position by a ground transponder and realize the position detection, speed detection and train running direction judgment of the train by train-ground wireless communication. When the ground transponder is used for acquiring the train positioning, more vehicle-mounted sensors and vehicle-mounted equipment are required to be installed on each train, a large number of trackside equipment are installed along the line, the requirement on the external environment is high, and the wireless communication of the train ground which is easily affected by electromagnetic interference is excessively relied on, so that the reliability of the positioning result is low.

Therefore, in the prior art, in the process of positioning the train in real time, the reliability of the positioning result is low due to the fact that the wireless signal is poor.

Disclosure of Invention

In view of the foregoing, it is necessary to provide a system and a method for real-time continuous positioning of a train, so as to solve the problem in the prior art that the reliability of the positioning result is low due to poor wireless signals in the process of positioning the train in real time.

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

At least two array fiber bragg grating sensing optical cables are paved on a railway track bed of a train or embedded in a track plate, and are used for acquiring at least two groups of sensing signals of the train;

the demodulation module is used for demodulating at least two groups of sensing signals to obtain at least two groups of sensing signal data sequences;

and the signal processing module is used for fusing at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

Further, the two array fiber bragg grating sensing optical cables at least comprise a main sensing optical cable and a standby sensing optical cable;

the demodulation module at least comprises a first sub-demodulation module and a second sub-demodulation module;

the signal processing module at least comprises a first sub-signal processing module and a second sub-signal processing module;

the main sensing optical cable and the standby sensing optical cable can be backed up mutually;

the first sub-demodulation module is used for demodulating a first sensing signal data sequence acquired by the main sensing optical cable and inputting the first sensing signal data sequence into the first sub-signal processing module;

the second sub-demodulation module is used for demodulating a second sensing signal data sequence acquired by the standby sensing optical cable and inputting the second sensing signal data sequence to the second sub-signal processing module.

Further, the device also comprises a narrow bandwidth laser, an electro-optical modulator, a fiber amplifier, a first circulator, a second circulator and a Michelson interferometer;

wherein the narrow bandwidth laser is used for generating an initial optical signal;

the electro-optical modulator is used for modulating the initial optical signal to obtain a pulse optical signal;

the optical fiber amplifier is used for amplifying the pulse optical signals to obtain amplified pulse optical signals, transmitting the amplified pulse optical signals to the array fiber grating sensing optical cable through the first circulator, and obtaining the optical fiber pulse optical signals through reflection and transmission of the array fiber grating sensing optical cable;

the optical fiber pulse optical signal is transmitted to the Michelson interferometer through the second circulator, and the second circulator outputs a first detection optical signal;

the Michelson interferometer is used for carrying out interference processing on the optical fiber pulse optical signals to obtain second detection optical signals.

Further, the Michelson interferometer comprises a coupler, a first Faraday mirror, a second Faraday mirror and a delay optical fiber, wherein the length of the delay optical fiber is the same as the interval of the array fiber grating;

the coupler is used for carrying out coupling treatment on the optical fiber pulse optical signals to obtain a first optical fiber pulse optical signal and a second optical fiber pulse optical signal;

The first optical fiber pulse optical signal passes through a first Faraday mirror and outputs a first interference detection optical signal;

and after the second optical fiber pulse optical signal passes through the delay optical fiber, outputting a second interference detection optical signal through a second Faraday mirror.

Further, the demodulation module comprises a first photoelectric detector, a second photoelectric detector, a first analog-to-digital converter, a second analog-to-digital converter, a first FPGA group and a second FPGA group;

the first photoelectric detector is used for performing photoelectric conversion on the first detection optical signal and the first interference detection optical signal to obtain a first original electric signal and a second original electric signal;

the second photoelectric detector is used for performing photoelectric conversion on the first detection optical signal, the first interference detection optical signal and the second interference detection optical signal, and performing split-into-two processing to obtain a first group of interference electric signals and a second group of interference electric signals;

the first FPGA group is used for carrying out analog-to-digital conversion on the first original electric signal and the first group of interference electric signals to obtain a first group of sensing signal data sequences;

the second FPGA group is used for carrying out analog-to-digital conversion on the second original electric signal and the second interference electric signal to obtain a second group of sensing signal data sequences;

Wherein the first set of interference electrical signals and the second set of interference electrical signals each comprise three paths;

the first photodetector and the second photodetector may be back-up with each other;

the first analog-to-digital converter and the second analog-to-digital converter can be mutually backed up;

the first FPGA group and the second FPGA group may be backup to each other.

In order to solve the above problems, the present application further provides a real-time continuous positioning method for a train, including:

acquiring at least two groups of sensing signals of a train based on at least two array fiber grating sensing optical cables;

demodulating at least two groups of sensing signals based on a demodulator to obtain at least two groups of sensing signal data sequences;

and based on the signal processing module, fusing at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

Further, sequence detection is performed on the fused sensing signal data sequence, including:

collecting the fused sensing signal data sequence in real time according to a preset time interval, and calculating the RMS value of each signal segment;

comparing the RMS value with a preset RMS threshold value, and judging whether vibration exists in a corresponding measuring area of each signal segment;

When the RMS value is larger than a preset RMS threshold value, judging that vibration exists in the detection area, marking the detection area as an occupied detection area, and marking the detection area as 1 on a fusion sensing signal data sequence corresponding to the detection area;

when the RMS value is not greater than the preset RMS threshold value, judging that vibration does not exist in the detection zone, marking the detection zone as an unoccupied detection zone, and marking the detection zone as 0 on a fusion sensing signal data sequence corresponding to the detection zone;

and determining a sequence detection result of the fused sensing signal data sequence according to the sequence labeling result.

Further, determining a sequence detection result of the fused sensing signal data sequence according to the sequence labeling result, including:

acquiring a sensing data 0-1 sequence corresponding to the real-time sensing data sequence of each area;

when the labeling value in any sensing data 0-1 sequence is converted, recording the converted data segment length;

presetting a data segment length threshold;

stopping recording when the converted data segment length is not less than the data segment length threshold;

and when the converted data segment length is smaller than the data segment length threshold value and the conversion occurs again, stopping recording and correcting the marked value corresponding to the converted data segment length to obtain a corrected sequence detection result.

Further, the train positioning information includes whether a running train, a train position and vehicle integrity information; sequence detection of the fused sensing signal data sequence to determine train positioning information, comprising:

determining whether an occupied area exists according to a sequence detection result;

when the occupied test is not existed, judging that no train is running;

when the occupied area exists, judging that a running train exists, and acquiring the occupied area position and the occupied total area number corresponding to the occupied area;

determining the position of the train according to the position of the occupied area;

presetting a standard number of areas;

and comparing the total occupied area number with the standard area number to determine the vehicle integrity information.

Further, the train positioning information also comprises a running direction and a running speed; sequence detection is carried out on the fused sensing signal data sequence to determine train positioning information, and the method further comprises the following steps:

acquiring a sequence detection result of a full line full area;

when the sequence detection result of a single zone is changed from 0 to 1/from 1 to 0, marking as occupation/unoccupied of the train to the zone;

acquiring a sequence detection conversion result of an adjacent region after the conversion time, and recording the length of an interval data sequence through which the conversion of a fusion sensing signal data sequence is completed;

Comparing the change trend of the sequence detection results of the adjacent areas, and determining the running direction;

acquiring the length of a measuring area and a sampling time interval;

determining the running speed according to the length of the measuring area, the sampling time interval and the interval data sequence length

The beneficial effects of the application are as follows: the application provides a real-time continuous positioning system and a real-time continuous positioning method for a train, wherein the system acquires a sensing signal of the train by arranging a fiber grating sensing optical cable on a railway track bed or in a railway plate of the train, and converts the continuous positioning problem of the train into a signal data extraction problem for carrying out data processing on the sensing signal; the process of acquiring the sensing signal of the array fiber bragg grating sensing optical cable is hardly interfered by the external environment, so that the method can effectively adapt to the condition of poor wireless signals and ensure the reliability of the basic data of the sensing signal; further, data acquisition is carried out by arranging at least two array fiber bragg grating sensing optical cables, so that the data redundancy is effectively improved, and the reliability of a train positioning result is improved.

Drawings

FIG. 1 is a schematic diagram of a first embodiment of a real-time continuous train positioning system according to the present application;

fig. 2 is a schematic structural diagram of a second embodiment of the train real-time continuous positioning system provided by the application;

Fig. 3 is a schematic structural diagram of an embodiment of a demodulation module according to the present application;

FIG. 4 is a schematic flow chart of an embodiment of a method for real-time continuous positioning of a train according to the present application;

FIG. 5 is a schematic flow chart of an embodiment of sequence detection for a fused sensing signal data sequence according to the present application;

FIG. 6 is a flowchart illustrating an embodiment of a modified sequence labeling result provided by the present application;

fig. 7 is a schematic flow chart of a first embodiment of determining train positioning information according to the present application;

fig. 8 is a schematic flow chart of a second embodiment of determining train positioning information according to the present application.

Detailed Description

The following detailed description of preferred embodiments of the application is made in connection with the accompanying drawings, which form a part hereof, and together with the description of the embodiments of the application, are used to explain the principles of the application and are not intended to limit the scope of the application.

In the railway signal field, the blocking means that after a train enters a section, stations at two ends of the section do not send out a train to the section any more so as to prevent the train from collision and rear-end collision. The real-time detection of the train position is the basis for realizing the blocking control and is the core of a train safe operation control system. The blocking method can be divided into three types according to whether there is a fixed partition in the train position detection: fixed occlusion, quasi-mobile occlusion, mobile occlusion.

The early railway is a fixed block, a track circuit technology is adopted to detect the zone where the train is located, the track circuit divides the zone between two stations into a plurality of block zones, and only one train is allowed to run in each block zone. The track circuit technology has long partition length (about several kilometers to tens kilometers) for train positioning, and the train passing efficiency is low, so that the requirement of urban track traffic development is not met.

Currently, railway transportation and urban rail transportation are currently mostly quasi-mobile occlusion systems. The technology for positioning and measuring the speed of the train is to measure the speed through a speed sensor arranged on the train, correct the position by utilizing a ground transponder, and realize the position detection, the speed detection and the train running direction judgment of the train through train-ground wireless communication, and has the following defects: (1) The ground transponder still only detects the occupation region of the train, the specific position of the train in the region is indirectly obtained through calculation of a train velocimeter, and the positioning error is larger; (2) The vehicle integrity detection capability is not achieved, and a special axle counting device is required to be installed beside a track to assist in completing the vehicle integrity detection; (3) The system is complex, more vehicle-mounted sensors and vehicle-mounted equipment are required to be installed on each train, a large number of trackside equipment is required to be installed along the line, and the wireless communication of the train ground which is easily affected by electromagnetic interference is excessively depended on, so that when the key equipment and the communication link are failed, the system is degraded into automatic inter-station blocking, only one train is allowed to run between two adjacent stations, and the influence on the transportation capability is great.

Therefore, in the prior art, in the process of acquiring train operation data in real time, the problem of low accuracy of the train operation data caused by poor wireless signals exists.

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

As shown in fig. 1, fig. 1 is a schematic structural diagram of a first embodiment of a real-time continuous train positioning system provided by the present application, where the real-time continuous train positioning system includes:

the system comprises at least two array fiber bragg grating sensing optical cables (11 and 12), wherein the array fiber bragg grating sensing optical cables (11 and 12) are paved on a railway bed or in a railway plate of a train and are used for acquiring at least two groups of sensing signals of the train;

the demodulation module 20 is configured to demodulate at least two groups of sensing signals to obtain at least two groups of sensing signal data sequences;

the signal processing module 30 is configured to fuse at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and perform sequence detection on the fused sensing signal data sequence to determine train positioning information.

In the embodiment, at least two groups of sensing signals of a train can be obtained in real time by arranging at least two array fiber grating sensing optical cables (11 and 12) on a railway track bed or in a track plate of the train; demodulating at least two groups of sensing signals in real time based on the demodulation module 20 to obtain at least two groups of sensing signal data sequences; finally, the signal processing module 30 fuses at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence with higher reliability, and sequence detection is performed on the fused sensing signal data sequence to determine train positioning information.

In the embodiment, the continuous positioning problem of the train is converted into the signal data extraction problem of carrying out data processing on the sensing signals of the array fiber grating sensing optical cables (11 and 12) paved on the track bed of the train or embedded in the track plate, and the process of acquiring the sensing signals of the array fiber grating sensing optical cables (11 and 12) is hardly interfered by the external environment, so that the wireless signal poor condition can be effectively adapted, and the reliability of the basic data of the sensing signals is ensured; further, as the condition that the stress on two sides of the train is uneven in the running process, the sensor signals of the train are obtained by arranging at least two array fiber bragg grating sensor optical cables (11 and 12), and the reliability of the train positioning result is improved by improving the redundancy of the train positioning data.

As a preferred embodiment, the at least two array fiber bragg grating sensing optical cables (11 and 12) at least comprise a main sensing optical cable and a standby sensing optical cable, wherein the main sensing optical cable and the standby sensing optical cable can independently realize real-time sensing of the running state of the train, and the main sensing optical cable and the standby sensing optical cable can be mutually backed up.

In order to improve the comprehensiveness of the acquired data, the main sensing optical cable and the standby sensing optical cable are respectively arranged on track beds or in track plates on the left side and the right side of the train, so that sensing signals on the left side of the train can be monitored, sensing signals on the right side of the train can be monitored, and nuances among the sensing signals can be amplified as much as possible.

In a specific embodiment, in order to improve the reliability of the array fiber bragg grating sensing optical cable, the array fiber bragg grating sensing optical cable is prevented from being damaged due to the change of external environment in the use process, and when the track slab is poured, the array fiber bragg grating sensing optical cable is buried on a track bed of a train or is buried in a reserved groove of the track slab. In addition, the sensing signal includes a vibration signal or a strain signal.

In other embodiments, the position of the arrayed fiber grating sensor cable may be set in other ways. The sensing signal may also exist in other forms of signal.

Further, the demodulation module at least comprises a first sub-demodulation module and a second sub-demodulation module, and the signal processing module at least comprises a first sub-signal processing module and a second sub-signal processing module;

the first sub-demodulation module is used for demodulating a first sensing signal data sequence acquired by the main sensing optical cable and inputting the first sensing signal data sequence into the first sub-signal processing module; the second sub-demodulation module is used for demodulating a second sensing signal data sequence acquired by the standby sensing optical cable and inputting the second sensing signal data sequence to the second sub-signal processing module.

In this embodiment, by respectively configuring the demodulation module and the signal processing module for the main sensing optical cable and the standby sensing optical cable, which are independent of each other, it is realized that any array fiber grating sensing optical cable can be used as the main and standby optical cables. The redundancy of data processing is effectively improved by processing multiple groups of data corresponding to the multiple array fiber bragg grating sensing optical cables of the train, so that the subtle parts can be amplified, problems can be found in time, the reliability of the data is improved, and the reliability of a positioning result is further improved.

In one embodiment, if one of the array fiber grating sensor cables is determined to be the primary sensor cable during one communication cycle, the remaining array fiber grating sensor cables are automatically determined to be the backup sensor cable to increase system redundancy. It should be noted that, the main and standby sensing optical cables can realize real-time switching, that is, all the array fiber bragg grating sensing optical cable channels are mutually backed up.

In a specific embodiment, on the basis of the two array fiber bragg grating sensing optical cables (11 and 12), a third array fiber bragg grating sensing optical cable or even more array fiber bragg grating sensing optical cables are arranged to acquire the sensing signals of the train, so that the reliability of the positioning result is improved.

In a specific embodiment, because the train running time interval is relatively stable, in order to improve the reliability of the main sensing optical cable, the communication time between the main sensing optical cable and the signal processing module 30 is also controlled, when the signal processing module 30 does not receive the sensing signal data of the main sensing optical cable within the timeout time threshold, the main sensing optical cable is judged to be invalid, the main sensing optical cable is replaced in real time, and the main sensing optical cable is switched to the standby sensing optical cable for data analysis processing.

As a preferred embodiment, in order to describe in detail the process of acquiring the sensing signal of the train based on the train real-time continuous positioning system, as shown in fig. 2, fig. 2 is a schematic structural diagram of a second embodiment of the train real-time continuous positioning system provided by the present application, the train real-time continuous positioning system 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;

the first circulator comprises a first port a, a second port b and a third port c, and the second circulator comprises a fourth port d, a fifth port e and a sixth port f;

a first port a is connected with the optical fiber amplifier 60, a second port b is connected with the array fiber grating sensing optical cable, a third port c is connected with a fourth port d, and a fifth port e is connected with the Michelson interferometer 90;

A narrow bandwidth laser 40 is used to generate the initial optical signal;

the electro-optical modulator 50 is used for modulating the initial optical signal to obtain a pulse optical signal;

the optical fiber amplifier 60 is used for amplifying the pulse optical signal to obtain an amplified pulse optical signal, transmitting the amplified pulse optical signal to the array fiber grating sensing optical cable through the first circulator 70, and obtaining an optical fiber pulse optical signal through reflection and transmission of the array fiber grating sensing optical cable;

the amplified pulse optical signal enters from the first port a, exits from the second port b and enters the array fiber grating sensing optical cable; the optical fiber pulse optical signals are obtained through reflection and transmission of the array fiber bragg grating sensing optical cable, enter from the second port b, exit from the third port c and enter into the second circulator 80;

the optical fiber pulse optical signal enters from the fourth port d and exits from the sixth port f to obtain a first detection optical signal; the optical fiber pulse optical signal enters from the fourth port d, exits from the fifth port e and enters the Michelson interferometer 90;

the michelson interferometer 90 is configured to perform interference processing on the optical fiber pulse optical signal to obtain a second detection optical signal.

In this embodiment, the optical fiber pulse optical signal is split into two parts by the second circulator 80, so that not only the first detection optical signal is obtained as a comparison standard, but also the second detection optical signal is obtained by performing interference processing on the optical fiber pulse optical signal by the michelson interferometer 90, so that the determination of the sensing signal of the train by the first detection optical signal and the second detection optical signal is realized, and the reliability of the sensing signal is ensured.

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 fiber 94, and the length of the delay fiber 94 is the same as the pitch of the arrayed fiber gratings;

wherein the second detection light signal comprises a first interference detection light signal and a second interference detection light signal;

the coupler 91 includes seventh ports g, eighth ports h and i;

and the seventh port g is connected to the fifth port e.

In the process of processing the second detection optical signal, the coupler 91 performs coupling processing on the optical fiber pulse optical signal to obtain a first optical fiber pulse optical signal and a second optical fiber pulse optical signal;

the first optical fiber pulse optical signal passes through the first faraday mirror 92 and the first interference detection optical signal is output by the eighth port h;

the second optical fiber pulse optical signal passes through the delay optical fiber 94, then passes through the second faraday mirror 93, and the second interference detection optical signal is output by i.

In this embodiment, the second detection optical signal is split into two parts by the coupler 91, and is processed by the first faraday mirror 92, the second faraday mirror 93 and the delay optical fiber 94 respectively, so as to obtain the first interference detection optical signal and the second interference detection optical signal, increase the number of interference optical signals, and improve the redundancy and reliability of data.

As a preferred embodiment, in order to demodulate the sensing signal, as shown in fig. 3, fig. 3 is a schematic structural diagram of an embodiment of a demodulation module provided by the present application, where 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;

wherein the first photodetector 21 is connected to the sixth port f and the eighth port h, respectively;

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

the first analog-to-digital converter 23 is respectively connected with the first photoelectric detector 21 and the first FPGA group 25;

the second analog-to-digital converter 24 is connected to the second photodetector 22 and the second FPGA group 26, respectively.

The first photodetector 21 is configured to photoelectrically convert the first detection optical signal and the first interference detection optical signal to obtain a first original electrical signal and a second original electrical signal;

the second photodetector 22 is configured to photoelectrically convert the first detection optical signal, the first interference detection optical signal, and the second interference detection optical signal, and perform a bisection process to obtain a first set of interference electrical signals and a second set of interference electrical signals;

the first FPGA group 25 is configured to perform analog-to-digital conversion on the first original electrical signal and the first set of interference electrical signals, to obtain a first set of sensing signal data sequences;

The second FPGA group 26 is configured to perform analog-to-digital conversion on the second original electrical signal and the second set of interference electrical signals to obtain a second set of sensing signal data sequences;

wherein the first set of interference electrical signals and the second set of interference electrical signals each comprise three paths;

the first photodetector 21 and the second photodetector 22 may be back-up with each other;

the first analog-to-digital converter 23 and the second analog-to-digital converter 24 may be back-up to each other;

the first FPGA group 25 and the second FPGA group 26 may be backups to each other.

In the embodiment, the first detection optical signal and the first interference detection optical signal are used as the signal group to perform photoelectric conversion, and finally a first group of sensing signal data sequences are obtained as reference standards, so that the influence of the circulator and the coupler on the final sensing signal data sequences is eliminated; the second photodetector 22 performs the one-to-two processing, so that the one-to-two output is realized, the redundancy of the data is improved, and the reliability of the data is improved by comparing and fusing the signals output by the one-to-two processing.

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 normally operate, the sensing signal of the train can still be obtained, and the whole system still includes a complete loop.

That is, when an extreme condition exists, the first photodetector 21 and the second photodetector 22 may be backed up, and only one of the photodetectors may be operated normally, the photoelectric signal conversion may still be implemented 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 may be back-up to each other; the first FPGA group 25 corresponds to the first analog-to-digital converter 23, and can implement analog-to-digital conversion to obtain a first group of sensing signal data sequences; the second FPGA group 26 corresponds to the second analog-to-digital converter 24 and is capable of performing analog-to-digital conversion to obtain a second set of sensing signal data sequences.

That is, as long as there are a photodetector, an analog-to-digital converter and a corresponding FPGA group that can operate normally, the acquisition of the sensing signal of the train can be realized.

In order to solve the above-mentioned problems, the present application further provides a real-time continuous positioning method for a train, as shown in fig. 4, fig. 4 is a schematic flow chart of an embodiment of the real-time continuous positioning method for a train provided by the present application, including:

step S101: acquiring at least two groups of sensing signals of a train based on at least two array fiber grating sensing optical cables;

step S102: demodulating the at least two groups of sensing signals based on a demodulator to obtain at least two groups of sensing signal data sequences;

Step S103: and based on a signal processing module, fusing the at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

In the embodiment, first, at least two groups of sensing signals of a train are obtained based on at least two array fiber grating sensing optical cables; demodulating the at least two groups of sensing signals based on a demodulator to obtain at least two groups of sensing signal data sequences; and finally, fusing the at least two groups of sensing signal data sequences based on a signal processing module to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

In the embodiment, the sensing signal of the train is obtained by arranging the fiber grating sensing optical cable on the railway bed or in the railway plate of the train, and the continuous positioning problem of the train is converted into the signal data extraction problem of data processing of the sensing signal; the process of acquiring the sensing signal of the array fiber bragg grating sensing optical cable is hardly interfered by the external environment, so that the method can effectively adapt to the condition of poor wireless signals and ensure the reliability of the basic data of the sensing signal; further, data acquisition is carried out by arranging at least two array fiber bragg grating sensing optical cables, so that the data redundancy is effectively improved, and the reliability of a train positioning result is improved.

As a preferred embodiment, in step S103, in order to perform sequence detection on the fused sensing signal data sequence, as shown in fig. 5, fig. 5 is a flow chart of an embodiment of performing sequence detection on the fused sensing signal data sequence according to the present invention, which includes:

step S131: collecting the fused sensing signal data sequence in real time according to a preset time interval, and calculating the RMS value of each signal segment;

step S132: comparing the RMS value with a preset RMS threshold value, and judging whether vibration exists in a corresponding measuring area of each signal segment;

step S133: when the RMS value is larger than a preset RMS threshold value, judging that vibration exists in the detection area, marking the detection area as an occupied detection area, and marking the detection area as 1 on a fusion sensing signal data sequence corresponding to the detection area;

step S134: when the RMS value is not greater than the preset RMS threshold value, judging that vibration does not exist in the detection zone, marking the detection zone as an unoccupied detection zone, and marking the detection zone as 0 on a fusion sensing signal data sequence corresponding to the detection zone;

step S135: and determining a sequence detection result of the fused sensing signal data sequence according to the sequence labeling result.

In this embodiment, firstly, the acquired fused sensing 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 a preset RMS threshold value, carrying out refined judgment on the RMS value of each signal segment to determine the train running state corresponding to each preset time interval; whether vibration exists or not is judged through the RMS value of the signal section, and whether data with larger fluctuation exists in the fused sensing signal data sequence or not can be judged well, so that the reliability of a vibration judgment result is ensured; in addition, because the preset time interval is very short, the corresponding measuring area distance is also very short, and the length of the train is also relatively long, the positioning of the train can be determined in real time.

Further, since only the wheel tracks are in contact with the ground track during the running of the train to generate vibration signals, the carriage part between the two groups of wheel tracks is not in direct contact with the fiber bragg grating when entering the zone, so that the vibration signals are not recorded by the sensor. In order to further make the sequence detection result close to the train operation practice, and improve the accuracy and reliability of the sequence detection result, in step S135, after the sequence labeling result is obtained, the sequence labeling result needs to be corrected to determine the sequence detection result, as shown in fig. 6, fig. 6 is a flow chart of an embodiment of the corrected sequence labeling result provided by the invention, which includes:

step S1351: acquiring a sensing data 0-1 sequence corresponding to the real-time sensing data sequence of each area;

step S1352: when the labeling value in any sensing data 0-1 sequence is converted, recording the converted data segment length;

step S1353: presetting a data segment length threshold;

step S1354: stopping recording when the converted data segment length is not less than the data segment length threshold;

step S1355: and when the converted data segment length is smaller than the data segment length threshold value and the conversion occurs again, stopping recording and correcting the marked value corresponding to the converted data segment length to obtain a corrected sequence detection result.

In the implementation, in order to avoid subsequent positioning errors caused by the fact that no effective vibration signal is generated at the carriage part of the wheelless track, invalid vibration data is timely screened out and a sequence marking result which is converted is corrected by setting a data segment length threshold after the sensing data sequence output by each measuring area in real time is read.

As a preferred embodiment, the train positioning information includes information about whether a train is running or not, a train position and a train integrity, and in order to perform sequence detection on the fused sensing signal data sequence to determine the train positioning information, as shown in fig. 7, fig. 7 is a schematic flow chart of a first embodiment of determining the train positioning information provided by the present invention, including:

step S231: determining whether an occupied area exists according to a sequence detection result;

step S232: when the occupied test is not existed, judging that no train is running;

step S233: when the occupied area exists, judging that a running train exists, and acquiring the occupied area position and the occupied total area number corresponding to the occupied area;

step S234: determining the position of the train according to the position of the occupied area;

step S235: presetting a standard number of areas;

step S236: and comparing the total occupied area number with the standard area number to determine the vehicle integrity information.

It should be noted that, in step S231, the sequence detection result is in the form of "00011..1100" which only includes the numbers "0" and "1", where the number "0" represents that there is no effective vibration in its corresponding zone, and the number "1" represents that there is effective vibration in its corresponding zone, that is, there is a running train in the zone.

In this embodiment, since each sequence detection result "0" or "1" has its corresponding zone, and the location of the zone is a known quantity, it is possible to quickly determine that there is no running train on the zone and the train position based on the sequence detection result; because each sequence detection result of "0" or "1" corresponds to one of the zones, and the length of each zone is the same, the number of zones in which effective vibration exists can be quickly determined based on the sequence detection result, and whether the length of the current train meets the requirements, that is, whether the vehicle remains intact, can be determined based on the standard number of zones.

As a preferred embodiment, the train positioning information further includes a running direction and a running speed, and in order to perform sequence detection on the fused sensing signal data sequence to determine the train positioning information, as shown in fig. 8, fig. 8 is a schematic flow chart of a second embodiment of determining the train positioning information provided by the present invention, which includes:

Step S331: acquiring a sequence detection result of a full line full area;

step S332: when the sequence detection result of a single zone is changed from 0 to 1/from 1 to 0, marking as occupation/unoccupied of the train to the zone;

step S333: acquiring a sequence detection conversion result of an adjacent region after the conversion time, and recording the length of an interval data sequence through which the conversion of a fusion sensing signal data sequence is completed;

step S334: comparing the change trend of the sequence detection results of the adjacent areas, and determining the running direction;

step S335: acquiring the length of a measuring area and a sampling time interval;

step S336: and determining the running speed according to the length of the measuring area, the sampling time interval and the interval data sequence length.

In this embodiment, when a single zone sequence transitions from 0 to 1/1 to 0, it indicates that the current train occupies or unoccupied the zone, based on which, in order to determine the running direction of the train, the trend of the sequence detection results of adjacent zones is compared, and when the sequence detection result transitions from "0011..10000" to "0000011..10", it indicates that the current train is moving in a direction away from the first circulator, and conversely, in a direction approaching the first circulator.

Further, according to the principle that the sampling time interval of each section of data sequence is unchanged and the length of the measuring area is unchanged, after the length of the interval data sequence which is converted in the sampling time interval is obtained, the running speed is determined according to the length of the measuring area, the sampling time interval and the length of the interval data sequence.

In the embodiment, the real-time estimation calculation of the train speed and the running direction under the space-time range is realized by reading the real-time sensing data sequence of the full-line area and fusing the real-time sensing data sequence matrix of the full-line area, so that the problems that the continuous calculation update cannot be realized and the blind area and the communication interference exist under the non-transponder communication environment only by relying on the vehicle-mounted speed sensor to send the information of data, position and the like regularly by the vehicle-mounted communication system in the prior art are avoided.

According to the technical scheme, the sensing signal of the train is obtained by arranging the fiber grating sensing optical cable on the railway bed or in the railway plate of the train, and the continuous positioning problem of the train is converted into the signal data extraction problem of data processing of the sensing signal; the process of acquiring the sensing signal of the array fiber bragg grating sensing optical cable is hardly interfered by the external environment, so that the method can effectively adapt to the condition of poor wireless signals and ensure the reliability of the basic data of the sensing signal; further, data acquisition is carried out by arranging at least two array fiber bragg grating sensing optical cables, so that the data redundancy is effectively improved, and the reliability of a train positioning result is improved.

The vibration of the train is perceived through the fiber bragg grating sensing optical cable, and the vibration sensor is a direct and single type sensor and has a highly consistent positioning mode, so that the mode of the combined estimation positioning of the speed sensor and the transponder for the positioning of the existing train is innovated; in addition, the vibration signal of the train is obtained by arranging the fiber grating sensing optical cable, so that the method is a wired communication method, and the problems of various communication interferences existing in the train-ground wireless communication in the prior art, particularly unstable wireless communication in the lightning meteorological environment, are avoided; further, since the time interval for acquiring the sensing signal of the train through the fiber grating sensing optical cable is very short, the positioning information of the train can be continuously acquired in real time.

The present invention is not limited to the above-mentioned embodiments, and any changes or substitutions that can be easily understood by those skilled in the art within the technical scope of the present invention are intended to be included in the scope of the present invention.

Claims (10)

1. A real-time continuous positioning system for a train, comprising:

the at least two array fiber bragg grating sensing optical cables are paved on a railway bed of a train or embedded in a track plate and are used for acquiring at least two groups of sensing signals of the train;

The demodulation module is used for demodulating the at least two groups of sensing signals to obtain at least two groups of sensing signal data sequences;

and the signal processing module is used for fusing the at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

2. The real-time continuous positioning system of a train of claim 1, wherein the two arrayed fiber grating sensor cables comprise at least a primary sensor cable and a back-up sensor cable;

the demodulation module at least comprises a first sub-demodulation module and a second sub-demodulation module;

the signal processing module at least comprises a first sub-signal processing module and a second sub-signal processing module;

wherein the main sensing optical cable and the standby sensing optical cable can be backed up each other;

the first sub-demodulation module is used for demodulating a first sensing signal data sequence acquired by the main sensing optical cable and inputting the first sensing signal data sequence into the first sub-signal processing module;

the second sub-demodulation module is used for demodulating a second sensing signal data sequence acquired by the standby sensing optical cable and inputting the second sensing signal data sequence into the second sub-signal processing module.

3. The real-time continuous positioning system of a train of claim 1, further comprising 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 configured to generate an initial optical signal;

the electro-optical modulator is used for modulating the initial optical signal to obtain a pulse optical signal;

the optical fiber amplifier is used for amplifying the pulse optical signal to obtain an amplified pulse optical signal, transmitting the amplified pulse optical signal to the array fiber grating sensing optical cable through the first circulator, and obtaining an optical fiber pulse optical signal through reflection and transmission of the array fiber grating sensing optical cable;

the optical fiber pulse optical signal is transmitted to the Michelson interferometer through the second circulator, and a first detection optical signal is output by the second circulator;

the Michelson interferometer is used for carrying out interference processing on the optical fiber pulse optical signals to obtain second detection optical signals.

4. The real-time continuous train positioning system according to claim 3, wherein the michelson interferometer comprises a coupler, a first faraday mirror, a second faraday mirror and a delay fiber, and the length of the delay fiber is the same as the pitch of the array fiber grating;

The coupler carries out coupling treatment on the optical fiber pulse optical signals to obtain a first optical fiber pulse optical signal and a second optical fiber pulse optical signal;

the first optical fiber pulse optical signal passes through the first Faraday mirror and outputs the first interference detection optical signal;

and after the second optical fiber pulse optical signal passes through the delay optical fiber, the second interference detection optical signal is output through the second Faraday mirror.

5. The real-time continuous positioning system of a train of claim 4, wherein the demodulation module comprises a first photodetector, a second photodetector, a first analog-to-digital converter, a second analog-to-digital converter, a first FPGA group, a second FPGA group;

the first photoelectric detector is used for performing photoelectric conversion on the first detection optical signal and the first interference detection optical signal to obtain a first original electric signal and a second original electric signal;

the second photoelectric detector is used for performing photoelectric conversion on the first detection optical signal, the first interference detection optical signal and the second interference detection optical signal, and performing one-to-two processing to obtain a first group of interference electric signals and a second group of interference electric signals;

The first FPGA group is used for carrying out analog-to-digital conversion on the first original electric signal and the first group of interference electric signals to obtain a first group of sensing signal data sequences;

the second FPGA group is used for carrying out analog-to-digital conversion on the second original electric signal and the second group of interference electric signals to obtain a second group of sensing signal data sequences;

wherein the first set of interference electrical signals and the second set of interference electrical signals comprise three paths of the first photoelectric detector and the second photoelectric detector which can be mutually backed up;

the first analog-to-digital converter and the second analog-to-digital converter may be back-up to each other;

the first FPGA group and the second FPGA group may be backups of each other.

6. A real-time continuous train positioning method, which is applied to the real-time continuous train positioning system of any one of claims 1 to 5, and comprises the following steps:

acquiring at least two groups of sensing signals of a train based on at least two array fiber grating sensing optical cables;

demodulating the at least two groups of sensing signals based on a demodulator to obtain at least two groups of sensing signal data sequences;

and based on a signal processing module, fusing the at least two groups of sensing signal data sequences to obtain a fused sensing signal data sequence, and performing sequence detection on the fused sensing signal data sequence to determine train positioning information.

7. The method for real-time continuous positioning of a train according to claim 6, wherein the sequence detection of the fused sensor signal data sequence comprises:

the fusion sensing signal data sequence is acquired in real time according to 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 judging whether vibration exists in a corresponding detection area of each signal segment;

when the RMS value is larger than the preset RMS threshold value, judging that vibration exists in the detection area, marking the detection area as an occupied detection area, and marking the detection area as 1 on the fusion sensing signal data sequence corresponding to the detection area;

when the RMS value is not greater than the preset RMS threshold value, judging that vibration does not exist in the detection zone, marking the detection zone as an unoccupied detection zone, and marking the detection zone as 0 on the fusion sensing signal data sequence corresponding to the detection zone;

and determining a sequence detection result of the fusion sensing signal data sequence according to the sequence labeling result.

8. The method for real-time continuous positioning of a train according to claim 7, wherein determining the sequence detection result of the fused sensor signal data sequence according to the sequence labeling result comprises:

Acquiring a sensing data 0-1 sequence corresponding to the real-time sensing data sequence of each measuring area;

when any labeling value in the sensing data 0-1 sequence is converted, recording the converted data segment length;

presetting a data segment length threshold;

stopping recording when the converted data segment length is not less than the data segment length threshold;

and stopping recording and correcting the marked value corresponding to the converted data segment length when the converted data segment length is smaller than the data segment length threshold value and the conversion occurs again, so as to obtain a corrected sequence detection result.

9. The method for real-time continuous positioning of a train according to claim 7, wherein the train positioning information includes whether there is an operating train, a train position, and vehicle integrity information; performing sequence detection on the fused sensing signal data sequence to determine train positioning information, including:

determining whether the occupied area exists according to the sequence detection result;

when the occupied test is not present, judging that no train is running;

when the occupied area exists, judging that a running train exists, and acquiring the occupied area position and the occupied total area number corresponding to the occupied area;

Determining the train position according to the occupied area position;

presetting a standard number of areas;

and comparing the total occupied area number with the standard area number to determine the vehicle integrity information.

10. The method for real-time continuous positioning of a train according to claim 7, wherein the train positioning information further comprises a running direction and a running speed; performing sequence detection on the fused sensing signal data sequence to determine train positioning information, and further comprising:

acquiring the sequence detection result of a full line full area;

marking as the occupation/de-occupation of the train by the single detection zone when the sequence detection result of the detection zone changes from 0 to 1/from 1 to 0;

acquiring a sequence detection conversion result of an adjacent region after the conversion time, and recording the length of an interval data sequence through which the conversion of the fusion sensing signal data sequence is completed;

comparing the change trend of the sequence detection results of the adjacent areas, and determining the running direction;

acquiring the length of a measuring area and a sampling time interval;

and determining the running speed according to the length of the measuring area, the sampling time interval and the interval data sequence length.