CN113676278A

CN113676278A - LKJ timing method and device based on NTP and satellite clock

Info

Publication number: CN113676278A
Application number: CN202110955573.XA
Authority: CN
Inventors: 胡嗣钦; 王业流; 吴笑馨; 罗浩; 欧盛芬; 周兰芳; 李奋勇
Original assignee: Hunan CRRC Times Signal and Communication Co Ltd
Current assignee: Hunan CRRC Times Signal and Communication Co Ltd
Priority date: 2021-08-19
Filing date: 2021-08-19
Publication date: 2021-11-19

Abstract

The invention relates to the technical field of railway science, in particular to an LKJ timing method and device based on NTP and a satellite clock. The method comprises the following steps: step S1, acquiring time from the NTP server and acquiring time from the satellite clock; step S2, comparing the time obtained from the NTP server with the time obtained from the satellite clock, if the comparison is consistent, entering step S3 as accurate time, otherwise entering step S1; and step S3, if the system clock error of the current LKJ is judged to exceed a certain range, timing the LKJ by using accurate time. The method can effectively overcome the defects of the existing method, provides reliable, accurate and continuous time information for LKJ, greatly reduces manual participation, realizes automatic timing operation, is convenient and meets the field operation conditions, has high reliability, improves the production efficiency and reduces the traffic safety risk.

Description

LKJ timing method and device based on NTP and satellite clock

Technical Field

The invention relates to the technical field of railway science, in particular to an LKJ time correction method and device based on NTP (network time protocol) and a satellite clock.

Background

The train operation monitoring device (LKJ for short) is a train speed control system independently developed in China, has the functions of preventing a train from falsely sending signals, running over speed, assisting a driver to improve the operation capability and the like, and is an important component and important driving equipment of a Chinese train operation control system.

The accurate system clock is the benchmark for the LKJ device to realize the control function and the event analysis. Therefore, each time the LKJ device is checked in and out of the warehouse, the system clock of the LKJ device needs to be detected, and when the system clock of the LKJ device has a large error, the system clock of the LKJ device needs to be calibrated.

The currently adopted time correction technology of the LKJ equipment comprises special time corrector time correction, manual time correction and BD/GPS time correction.

When the special time corrector is used for time correction, a standard time system master clock is installed on the ground at each warehouse-out point where satellite signals are good. The input end of the master clock of the standard time system is connected with a BD/GPS antenna, accurate time is obtained through the BD/GPS system, when an operator goes out of a warehouse of the locomotive, the operator corrects the time of the special time corrector through the master clock of the standard time system, then the operator holds the special time corrector, gets on the locomotive and corrects the time of the LKJ equipment by using the special time corrector. The method has the following defects:

1) when a mother clock of a standard time system is deployed on the ground, a place which is clear, free of blocking and good in satellite signal needs to be selected;

2) the time correction method needs manual participation, is complex in link, wastes time and labor and is easy to cause missed correction;

3) the timing can only be carried out when an operator carries out detection operation, the problem of time error caused by the failure of the LKJ equipment after timing cannot be solved, and the timing method has no real-time property.

When the manual timing method is adopted, an operator sets the time of the LKJ manually through an operation interface provided by a display of the LKJ when the locomotive is detected out of the warehouse. The method has the following defects:

1) the condition of large error is easy to occur without reference time;

2) the time correction method completely depends on manual participation, and correction omission is easy to occur;

When the BD/GPS time correction method is adopted, the vehicle-mounted terminal is formed by the vehicle-mounted antenna and the vehicle-mounted host. The method can reduce manual participation and solve the problem of missed correction, but the most prominent defect in the method is that the accuracy of the time in correction completely depends on the accuracy of the acquired BD/GPS time, the BD/GPS signal has large influence on weather, environment and the like, and error time information can be output possibly when the BD/GPS receives signal interference, data communication or calculation error, so that error occurs in the time correction of the LKJ.

Disclosure of Invention

The invention aims to provide an LKJ timing method and device based on NTP and a satellite clock, and solves the problems of low real-time performance, accuracy and reliability of LKJ timing in the prior art.

In order to achieve the purpose, the invention provides an LKJ timing method based on NTP and a satellite clock, which comprises the following steps:

step S1, acquiring time from the NTP server and acquiring time from the satellite clock;

step S2, comparing the time obtained from the NTP server with the time obtained from the satellite clock, if the comparison is consistent, entering step S3 as accurate time, otherwise entering step S1;

and step S3, if the system clock error of the current LKJ is judged to exceed a certain range, timing the LKJ by using accurate time.

In an embodiment, the step S1, obtaining the time from the NTP server, further includes:

and sequentially carrying out communication interaction with a plurality of NTP servers until the time is successfully acquired.

and performing communication interaction with the NTP server through a wireless communication network.

In one embodiment, the step S1 of obtaining the time from the satellite clock further includes:

the time is acquired from the clock of the BD/GPS.

In order to achieve the purpose, the invention provides an LKJ timing device based on NTP and a satellite clock, which comprises a vehicle-mounted timing device and a vehicle-mounted antenna:

the vehicle-mounted antenna is arranged outside the locomotive and used for receiving satellite signals and communication signals of the NTP server;

the vehicle-mounted timing device collects time information of satellite signals through satellite signals received by a vehicle-mounted antenna, collects time information of an NTP server through communication signals of an NTP server received by the vehicle-mounted antenna, compares the collected satellite clock time with the time obtained from the NTP server to obtain accurate time, and performs timing on the LKJ if the system clock error of the current LKJ is judged to exceed a certain range.

In an embodiment, the vehicle-mounted timing device sequentially performs communication interaction with a plurality of NTP servers until time is successfully acquired.

In one embodiment, the vehicle-mounted timing device is provided with a wireless communication module, and is in communication interaction with an NTP server.

In one embodiment, the vehicle-mounted timing device is provided with a BD/GPS module, demodulates received satellite signals and collects time information of the BD/GPS.

In one embodiment, the number of the vehicle-mounted timing devices is not less than 2, and time comparison is performed between the vehicle-mounted timing devices to realize redundant backup.

The LKJ timing method and device based on the NTP and the satellite clock can effectively overcome the defects of the existing method, provide reliable, accurate and continuous time information for LKJ, greatly reduce manual participation, realize automatic timing operation, facilitate meeting field operation conditions, have high reliability, improve production efficiency and reduce driving safety risks.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings in which like reference numerals denote like features throughout the several views, wherein:

figure 1 discloses a flow chart of a LKJ timing method based on NTP and a satellite clock according to an embodiment of the invention;

figure 2 discloses a NTP communication flow diagram according to an embodiment of the present invention;

FIG. 3 discloses a LKJ timing flow diagram according to an embodiment of the invention;

figure 4 discloses a schematic diagram of an LKJ timing device based on NTP and a satellite clock according to an embodiment of the invention;

fig. 5 discloses a structural diagram of the vehicle-mounted timing device according to an embodiment of the invention.

The meanings of the reference symbols in the figures are as follows:

410 a locomotive;

411 a vehicle antenna;

412 on-board timing equipment;

413 train operation monitoring means;

421 NTP server;

422 NTP server;

a 42n NTP server;

430 BD/GPS satellites;

440 a wireless communication network;

510 an application program;

520 an operating system;

530 a main processor;

541 BD/GPS module;

542 a wireless communication module;

543 a CAN interface;

544 an ethernet interface;

545 memory.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

With the development of a wireless communication technology and a BD/GPS satellite communication technology and the rapid application of the technology to a railway, the invention provides an LKJ time correction method and device based on NTP and a satellite clock, and relates to the technical field of wireless communication and BD/GPS satellite communication, wherein a mobile communication network (5G/4G/3G) is used for acquiring time from an NTP server and comparing the time with the time acquired from a BD/GPS satellite, so that the accuracy and reliability of time information are ensured, and the time correction of an LKJ device is realized by using a related communication technology, so that the accuracy of the time of the LKJ device is ensured.

Fig. 1 discloses a flowchart of an LKJ timing method based on NTP and a satellite clock according to an embodiment of the present invention, and the LKJ timing method based on NTP and a satellite clock according to the present invention shown in fig. 1 includes the following steps:

And further, sequentially carrying out communication interaction with a plurality of NTP servers until the time is successfully acquired.

Further, the NTP server is communicatively interfaced via a wireless communication network.

The wireless communication network includes a 5G/4G/3G (fifth/fourth/third generation mobile communication system) network.

Further, in the present embodiment, the time is acquired from the clock of the BD/GPS.

While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance with one or more embodiments, occur in different orders and/or concurrently with other acts from that shown and described herein or not shown and described herein, as would be understood by one skilled in the art.

Fig. 2 discloses a schematic diagram of an LKJ timing apparatus based on NTP and a satellite clock according to an embodiment of the present invention, and as shown in fig. 2, the LKJ timing apparatus based on NTP and a satellite clock according to the present invention includes an on-vehicle timing device 412 and an on-vehicle antenna 411:

the vehicle-mounted antenna 411 is installed outside the locomotive 410 and receives satellite signals and communication signals of the NTP server;

the vehicle-mounted timing device 412 collects time information of satellite signals through satellite signals received by the vehicle-mounted antenna 411, collects time information of an NTP server through communication signals of the NTP server received by the vehicle-mounted antenna 411, compares the collected satellite clock time with time obtained from the NTP server to obtain accurate time, and if the system clock error of the current LKJ train operation monitoring device 413 is judged to exceed a certain range, the LKJ train operation monitoring device 413 is calibrated by using the accurate time.

Further, a vehicle-mounted antenna 411 is installed on the roof of the locomotive 410 to receive satellite signals of the BD/GPS satellites 430 and 5G/4G/3G signals of the wireless communication network 440.

Fig. 3 is a block diagram of an on-board timing device according to an embodiment of the present invention, and as shown in fig. 2 and 3, the on-board timing device 412 is equipped with a BD/GPS module 541 which demodulates received satellite signals and collects time information of the BD/GPS satellites 430;

the vehicle-mounted timing device 412 is provided with a wireless communication module 542, has a 5G/4G/3G wireless communication function, and can be communicated and interacted with a ground NTP server after dialing networking so as to acquire accurate time from the NTP server.

The vehicle-mounted timing device 412 is provided with a main processor 530, and the main processor 530 is provided with an application program 510 and an operating system 520.

If the vehicle-mounted timing equipment 412 judges that the system clock error of the current LKJ train operation monitoring device 413 exceeds a certain range, timing is carried out on the LKJ through the CAN interface 543 or the Ethernet interface 544.

The LKJ train operation monitoring device 413 collects a timing request sent by the LKJ timing device 412 through the CAN interface 543 or the ethernet interface 544, modifies a local system clock, and records the event through the memory 545.

NTP (Network Time Protocol) service is a Protocol for synchronizing computer Time, which can synchronize a computer with its server or clock source (e.g., quartz clock, GPS, etc.), can provide highly accurate Time correction (the difference between the standard and the standard on LAN is less than 1 millisecond, and tens of milliseconds on WAN), and can prevent malicious Protocol attacks via encryption confirmation. Time is propagated on the level of the NTP server.

The ground NTP server can adopt a domestic common public NTP network time server, and the cost of deployment and later maintenance can be reduced.

The vehicle-mounted timing device 412 can communicate and interact with a plurality of NTP servers, such as NTP server 421, NTP server 422.

Furthermore, in order to improve the accuracy and reliability of time correction, the number of the vehicle-mounted time correction devices 412 is not less than 2, and time comparison is performed between the vehicle-mounted time correction devices 412 to realize redundant backup.

Optionally, the vehicle-mounted timing device 412 may adopt double redundancy, and the collected clock source is compared between the double redundancy, so that the accuracy of the clock source may be improved.

According to the LKJ timing device based on the NTP and the satellite clock, the service flow for realizing LKJ timing can be divided into an NTP communication flow and an LKJ timing flow.

Figure 4 discloses an NTP communication flow diagram according to an embodiment of the present invention, and as shown in figure 4, the NTP communication flow for obtaining time from an NTP server further includes the following steps:

step S101, selecting a first NTP server 421;

step S102, acquiring time from the NTP server, judging whether the acquisition is successful, if so, entering step S103, otherwise, entering step S104;

step S103, updating the system time of the vehicle-mounted timing device 412 by adopting the time acquired by the NTP server, wherein the NTP communication is successful and the process is finished;

and step S104, judging whether all the NTP servers finish communication, if not, selecting the next NTP server to enter step S102, and if so, failing the NTP communication and ending the process.

Fig. 5 is a timing flowchart of LKJ according to an embodiment of the present invention, and as shown in fig. 5, the timing flowchart of LKJ further includes the following steps:

step S201, judging whether effective time information is acquired from the BD/GPS satellite 430, if so, entering step S202, otherwise, entering step S302;

step S202, judging whether the time acquisition from the NTP server is successful, if so, entering step S203, otherwise, entering step S302;

step S203, judging whether the time of the slave BD/GPS is consistent with the system time of the vehicle-mounted timing device 412, if so, entering step S204, otherwise, entering step S302;

step S204, judging whether the current LKJ time error exceeds a certain range, if so, entering step S301, otherwise, entering step S302;

step S301, timing the LKJ;

and step S302, ending the process.

The LKJ timing method and device based on the NTP and the satellite clock have the following advantages:

1) by adopting an advanced wireless communication technology, the characteristics of wide coverage range, high speed and low time delay of a 5G/4G/3G network of an operator are fully exerted, and accurate clock information can be acquired from a public NTP server in real time through an NTP protocol;

2) the mode of mutual verification of the NTP clock and the BD/GPS clock is adopted, so that the accuracy and reliability of a clock source are ensured;

3) real-time and continuous clock information is acquired through the NTP and the BD/GPS, real-time correction can be carried out on the LKJ system clock, manual participation is not needed in the whole process, all automatic completion is achieved, and railway operation efficiency is improved.

Those of skill in the art would understand that information, signals, and data may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits (bits), symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The various illustrative logical modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software as a computer program product, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a web site, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk (disk) and disc (disc), as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks (disks) usually reproduce data magnetically, while discs (discs) reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

As used in this application and the appended claims, the terms "a," "an," "the," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.

The embodiments described above are provided to enable persons skilled in the art to make or use the invention and that modifications or variations can be made to the embodiments described above by persons skilled in the art without departing from the inventive concept of the present invention, so that the scope of protection of the present invention is not limited by the embodiments described above but should be accorded the widest scope consistent with the innovative features set forth in the claims.

Claims

1. An LKJ timing method based on NTP and a satellite clock is characterized by comprising the following steps:

2. The LKJ timing method based on NTP and a satellite clock according to claim 1, wherein the step S1 of obtaining time from an NTP server further includes:

3. The LKJ timing method based on NTP and a satellite clock according to claim 1, wherein the step S1 of obtaining time from an NTP server further includes:

4. The method for LKJ timing based on NTP and a satellite clock according to claim 1, wherein in step S1, obtaining the time from the satellite clock further includes:

the time is acquired from the clock of the BD/GPS.

5. The utility model provides a LKJ timing device based on NTP and satellite clock which characterized in that, includes on-vehicle timing equipment and on-vehicle antenna:

the vehicle-mounted timing device collects time information of satellite signals through satellite signals received by a vehicle-mounted antenna, collects time information of an NTP server through communication signals of an NTP server received by the vehicle-mounted antenna, compares the collected satellite clock time with the time obtained from the NTP server to obtain accurate time, and corrects the time of the LKJ by using the accurate time if the system clock error of the current LKJ is judged to exceed a certain range.

6. The NTP and satellite clock-based LKJ timing apparatus of claim 5, wherein the on-board timing device sequentially communicates with a plurality of NTP servers until time is successfully acquired.

7. An LKJ timing device based on NTP and a satellite clock as claimed in claim 5, wherein the vehicle-mounted timing equipment is provided with a wireless communication module and is in communication interaction with an NTP server.

8. An LKJ timing device based on NTP and a satellite clock according to claim 5, wherein the vehicle-mounted timing device is equipped with a BD/GPS module, demodulates received satellite signals, and collects time information of the BD/GPS.

9. The LKJ timing device based on the NTP and the satellite clock as claimed in claim 5, wherein the number of the vehicle-mounted timing devices is not less than 2, time comparison is conducted among the vehicle-mounted timing devices, and redundant backup is achieved.