Query-response type distance measurement method and device for rail transit application and medium

Abstract

The invention relates to the technical field of train control, and provides a rail transit application-oriented inquiry-response type distance measurement method and device and a medium, and an inquiry machine and a response machine are respectively arranged at a vehicle-mounted radar terminal and a trackside radar terminal; the method comprises the following steps: an interrogator and a responder calculate respective signal processing fixed time delays; the interrogator transmits an interrogation signal to the responder; the responder receives the inquiry signal and generates and transmits a response signal after the first correlation peak is detected; a responder signal processing fixed time delay and a random delay time delay are added into the response signal; and the interrogator receives the response signal, and after a second correlation peak is detected, the measurement distance is calculated based on the moment corresponding to the correlation peak of the response signal, the interrogator signal processing fixed time delay, the responder signal processing fixed time delay and the random response time delay. According to the invention, continuous, real-time and high-precision distance measurement can be realized, the distance measurement is not influenced by the environment, the driving safety capability of the train is improved, and the accident occurrence probability is reduced.

Description

Technical Field

[0001] The present invention relates to the field of train control technology, and in particular to a query-response ranging method, device, and medium for rail transit applications. Background Art

[0002] Increasing train speeds is a key goal in railway technology development, and the safety valve for achieving this goal is the train control system (TCS). The TCS prevents trains from exceeding the permitted speeds specified on the line, manages block areas between tracks, and prevents rear-end collisions. However, the frequent occurrence of rear-end collisions in the past two years demonstrates the current lack of comprehensive monitoring methods during train operation and a lack of reliable measures for monitoring the distance between preceding and following vehicles.

[0003] Specifically, traditional train control systems using satellite positioning technology face positioning issues in areas with low satellite visibility (such as tunnels), areas with severe multipath reflections (such as urban areas with tall buildings), and areas with significant electromagnetic interference. This, combined with the inherent large positioning errors of satellite positioning technology, makes it inadequate for train collision avoidance. Therefore, a precise and stable ranging technology is needed to monitor the positions of trains in real time and provide early warnings to drivers. Summary of the Invention

[0004] The present invention aims to provide a query-response ranging method, device and medium for rail transit applications to solve the problems of traditional train control systems such as poor satellite signal reception, inability to measure distance, and insufficient ranging accuracy.

[0005] In a first aspect, the present invention provides an interrogation-response ranging method for rail transit applications, wherein an interrogator and a transponder are respectively provided at a vehicle-mounted radar terminal and a trackside radar terminal; the interrogation-response ranging method comprises:

[0006] The interrogator and transponder calculate their respective fixed signal processing delays;

[0007] The interrogator transmits an interrogation signal to the transponder;

[0008] The transponder receives the interrogation signal and, after detecting the first correlation peak, generates and transmits a response signal; the response signal is added with a fixed delay for transponder signal processing and a random delay;

[0009] The interrogator receives the response signal and, after detecting the second correlation peak, calculates the measured distance based on the time corresponding to the response signal correlation peak, the interrogator signal processing fixed delay, the transponder signal processing fixed delay and the random response delay.

[0010] In some embodiments, in step S100, the interrogator and the transponder calculate their respective signal processing fixed delays by sending a self-test signal.

[0011] In some embodiments, step S200 includes the following sub-steps:

[0012] S201, the interrogator generates an interrogation ranging sequence G1 according to a set period;

[0013] S202, modulating the interrogation ranging sequence G1 with a first pseudo-random code to generate an interrogation signal;

[0014] S203: Transmit the inquiry signal and trigger the timer to start timing.

[0015] In some embodiments, step S300 includes the following sub-steps:

[0016] S301: The transponder receives the interrogation signal and performs first correlation peak detection through cross-correlation calculation to obtain an interrogation signal correlation peak.

[0017] S302: After detecting the interrogation signal correlation peak, generate a response ranging sequence G2 according to a set period, modulate the response ranging sequence G2 with a second pseudo-random code to generate a response signal; and add a fixed transponder signal processing delay and a random delay to the response signal for the interrogator to calculate the propagation path delay.

[0018] S303: After waiting for a random delay time, the transponder sends the response signal.

[0019] In some embodiments, step S301 specifically includes: after the transponder receives the interrogation signal and demodulates the interrogation signal, decorrelating the interrogation ranging sequence G1, performing cross-correlation calculation between the transponder local code and the interrogation ranging sequence G1 to obtain a first correlation peak value; if the calculated correlation peak value exceeds a first set threshold value, it is the detected interrogation signal correlation peak.

[0020] In some embodiments, step S400 includes the following sub-steps:

[0021] S401: The interrogator completes second correlation peak detection through cross-correlation calculation to obtain the response signal correlation peak, and triggers a timer to stop timing to obtain the time corresponding to the response signal correlation peak.

[0022] S402: The interrogator calculates the measured distance based on the time corresponding to the response signal correlation peak, the interrogator signal processing fixed delay, the response signal processing fixed delay, and the random response delay.

[0023] In some embodiments, step S401 specifically includes: after the interrogator receives the response signal and demodulates the response signal, decorrelating the response ranging sequence G2, generating a pseudocode sequence identical to the second pseudorandom code, and performing a cross-correlation calculation on the pseudocode sequence and the response ranging sequence G2 to obtain a second correlation peak value. If the calculated correlation peak value exceeds a second set threshold, it is a detected response signal correlation peak.

[0024] In some embodiments, the measured distance is expressed as:

[0025]

[0026] Where L is the measured distance, T is the time corresponding to the correlation peak of the reply signal, T1 is the fixed delay of the interrogator signal processing, T2 is the fixed delay of the transponder signal processing, T3 is the random reply delay, and c is the speed of light.

[0027] In a second aspect, the present invention provides an electronic device, comprising:

[0028] at least one processor; and a memory communicatively coupled to the at least one processor;

[0029] The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the above method by executing the instructions stored in the memory.

[0030] In a third aspect, the present invention provides a computer-readable storage medium for storing instructions, which implement the above method when the instructions are executed.

[0031] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0032] By rationally deploying interrogators and transponders at vehicle-mounted radar terminals and trackside radar terminals, the present invention can achieve continuous, real-time, and high-precision ranging, and is unaffected by environments such as areas with low satellite visibility (such as tunnels), areas with severe multipath reflections (such as urban high-rise buildings), and areas with severe electromagnetic interference. This helps improve the driving safety of trains and reduce the probability of accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a flow chart of a query-response ranging method for rail transit applications proposed in an embodiment of the present invention.

[0034] Figure 2 This is a schematic diagram of a query-response ranging method for rail transit applications proposed in an embodiment of the present invention.

[0035] Figure 3 This is a schematic structural diagram of an electronic device proposed in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0038] Traditional train control systems suffer from issues such as poor satellite signal reception, inability to measure distance, and insufficient ranging accuracy. The interrogation-response ranging method measures the distance between the interrogator and the transponder by timing the delay between the interrogator's interrogation signal and the transponder's response. This method's ranging accuracy is determined by timing precision and is not limited by distance, thus achieving highly accurate and reliable ranging regardless of distance.

[0039] Based on this, the embodiment of the present invention proposes an inquiry-response ranging method for rail transit applications. By properly deploying interrogators and transponders, it can achieve continuous, real-time, high-precision ranging, and is not affected by environments such as areas with low satellite visibility (such as tunnels), areas with severe multipath reflections (such as urban high-rise buildings), and areas with severe electromagnetic interference. Figure 1 As shown, the interrogator and the transponder are respectively provided at the vehicle-mounted radar terminal and the trackside radar terminal. The interrogation-response ranging method for rail transit applications includes the following steps:

[0040] S100: The interrogator and the transponder calculate their respective fixed signal processing delays.

[0041] In some embodiments, before starting ranging, the interrogator and transponder send a self-test signal to calculate and record their respective fixed signal processing delays for subsequent ranging value calculations. The interrogator's fixed signal processing delay is recorded as T1, and the transponder's fixed signal processing delay is recorded as T2. The self-test signal is specifically generated for use in calculating the fixed signal processing delays.

[0042] S200: The interrogator transmits an interrogation signal to the transponder.

[0043] In some embodiments, step S200 includes the following sub-steps:

[0044] S201, the interrogator generates an interrogation ranging sequence G1 according to a set period;

[0045] S202, modulating the interrogation ranging sequence G1 with a first pseudo-random code to generate an interrogation signal;

[0046] S203: The transmitting unit transmits the inquiry signal to the target within the coverage of the antenna beam, and simultaneously triggers a timer to start timing.

[0047] S300, the transponder receives the inquiry signal, and after detecting the first correlation peak, generates and transmits a response signal; the response signal is added with a transponder signal processing fixed delay and a random delay.

[0048] In some embodiments, step S300 includes the following sub-steps:

[0049] In step S301, a transponder receives an interrogation signal and performs a cross-correlation calculation to detect a first correlation peak, thereby obtaining an interrogation signal correlation peak. Specifically, after receiving and demodulating the interrogation signal, the transponder decorrelates the interrogation ranging sequence G1 and cross-correlates the transponder local code with the interrogation ranging sequence G1 to obtain a first correlation peak. If the calculated correlation peak exceeds a first set threshold, it is considered the detected interrogation signal correlation peak.

[0050] S302: After detecting the correlation peak of the interrogation signal, generate a response ranging sequence G2 according to a set period, modulate the response ranging sequence G2 with a second pseudo-random code to generate a response signal; and add a fixed delay for transponder signal processing and a random delay to the response signal for the interrogator to calculate the propagation path delay.

[0051] S303: After waiting for a random delay time, the transponder sends the response signal.

[0052] S400: The interrogator receives the response signal and calculates the measured distance.

[0053] In some embodiments, step S400 includes the following sub-steps:

[0054] In step S401, the interrogator detects the response signal correlation peak and triggers a timer to stop timing to obtain the time corresponding to the response signal correlation peak. Specifically, after receiving and demodulating the response signal, the interrogator decorrelates the response ranging sequence G2. The interrogator generates a pseudo-code sequence identical to the second pseudo-random code. The correlation peak between the pseudo-code sequence and the response ranging sequence G2 is the response signal correlation peak. Specifically, the pseudo-code sequence is cross-correlated with the response ranging sequence G2 to obtain a second correlation peak. If the calculated correlation peak exceeds a second predetermined threshold, it is considered the detected response signal correlation peak. The timer is triggered to stop timing to obtain the time corresponding to the response signal correlation peak. The timer can then be used to measure the propagation delay from the interrogator to the transponder.

[0055] S402: The interrogator calculates the measured distance based on the time corresponding to the response signal correlation peak, the interrogator signal processing fixed delay, the response signal processing fixed delay, and the random response delay.

[0056] The distance between the vehicle-mounted radar terminal and the trackside radar terminal can be measured by time calculation to obtain the ranging signal transmission time. The ranging accuracy is mainly determined by the time corresponding to the peak of the response signal. Figure 2 As shown, the measured distance is expressed as:

[0057]

[0058] Where L is the measured distance, T is the time corresponding to the correlation peak of the reply signal, T1 is the fixed delay of the interrogator signal processing, T2 is the fixed delay of the transponder signal processing, T3 is the random reply delay, and c is the speed of light.

[0059] Based on the same technical concept, an embodiment of the present invention further provides an electronic device that can implement the query-response ranging method process for rail transit applications provided in the above embodiment of the present invention. In one embodiment, the electronic device can be a server, or a terminal device or other electronic device. Figure 3 As shown, the electronic device may include:

[0060] At least one processor, and a memory connected to the at least one processor. The embodiment of the present invention does not limit the specific connection medium between the processor and the memory. Figure 3 The example in this article is that the processor and memory are connected via a bus. Figure 3 The connections between the other components are shown in bold lines, which are only for illustration and not intended to be limiting. The bus can be divided into address bus, data bus, control bus, etc. Figure 3The processor is represented by a single thick line, but this does not mean that there is only one bus or only one type of bus. Alternatively, the processor can also be called a controller, without any limitation on the name.

[0061] In an embodiment of the present invention, the memory stores instructions that can be executed by at least one processor. By executing the instructions stored in the memory, the at least one processor can execute the query-response ranging method for rail transit applications discussed above.

[0062] Among them, the processor is the control center of the device, which can use various interfaces and lines to connect the various parts of the entire control device, and monitor the device as a whole by running or executing instructions stored in the memory and calling data stored in the memory, the various functions of the device and processing data.

[0063] In an optional design, the processor may include one or more processing units, and the processor may integrate an application processor and a modem processor, wherein the application processor primarily processes the operating system, user interface, and application programs, and the modem processor primarily processes wireless communications. It is understood that the modem processor may not be integrated into the processor. In some embodiments, the processor and memory may be implemented on the same chip, or in some embodiments, they may be implemented on separate chips.

[0064] The processor can be a general-purpose processor, such as a CPU, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. A general-purpose processor can be a microprocessor or any conventional processor. The steps of the query-response ranging method for rail transit applications disclosed in the embodiments of the present invention can be directly implemented as a hardware processor, or can be implemented using a combination of hardware and software modules in the processor.

[0065] As a non-volatile computer-readable storage medium, memory can be used to store non-volatile software programs, non-volatile computer executable programs and modules. Memory can include at least one type of storage medium, for example, can include flash memory, hard disk, multimedia card, card-type memory, random access memory (Random Access Memory, RAM), static random access memory (Static Random Access Memory, SRAM), programmable read-only memory (Programmable Read Only Memory, PROM), read-only memory (Read Only Memory, ROM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), magnetic memory, disk, optical disk, etc. Memory is any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present invention can also be a circuit or any other device that can realize a storage function, for storing program instructions and / or data.

[0066] By designing and programming a processor, the code corresponding to the interrogation-response ranging method for rail transit applications described in the aforementioned embodiment can be embedded in the chip, enabling the chip to execute the steps of the method described in the aforementioned embodiment during operation. Designing and programming a processor is well known to those skilled in the art and will not be further described here.

[0067] Based on the same inventive concept, an embodiment of the present invention further provides a storage medium storing computer instructions. When the computer instructions are executed on a computer, the computer executes the query-response ranging method for rail transit applications discussed above.

[0068] In some optional embodiments, the present invention also provides various aspects of a query-response ranging method for rail transit applications, which can also be implemented in the form of a program product, which includes program code. When the program product is run on an apparatus, the program code is used to enable the control device to execute the steps of a query-response ranging method for rail transit applications according to various exemplary embodiments of the present invention described above in this specification.

[0069] It should be noted that although several units or subunits of the device are mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to an embodiment of the present invention, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of a unit described above can be further divided into multiple units to be embodied. In addition, although the operations of the method of the present invention are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. Additionally or alternatively, certain steps can be omitted, multiple steps can be combined into one step, and / or one step can be decomposed into multiple steps.

[0070] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0071] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a server, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the process in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0072] Program code for performing the operations of the present invention may be written using any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's device, as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0073] Where a remote computing device is involved, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0074] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0075] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0076] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A query-response ranging method for rail transit applications, characterized in that: The interrogator and the transponder are respectively arranged at the vehicle-mounted radar terminal and the trackside radar terminal; the interrogation-response ranging method includes: The interrogator and transponder calculate their respective fixed signal processing delays; The interrogator transmits an interrogation signal to the transponder; The transponder receives the interrogation signal and, after detecting the first correlation peak, generates and transmits a response signal; the response signal is added with a fixed delay for transponder signal processing and a random delay; The interrogator receives the response signal and, after detecting the second correlation peak, calculates the measured distance based on the time corresponding to the response signal correlation peak, the interrogator signal processing fixed delay, the transponder signal processing fixed delay and the random response delay.

2. The inquiry-response ranging method for rail transit applications according to claim 1, characterized in that: In step S100, the interrogator and the transponder calculate their respective signal processing fixed delays by sending a self-test signal.

3. The inquiry-response ranging method for rail transit applications according to claim 1, characterized in that: Step S200 includes the following sub-steps: S201, the interrogator generates an interrogation ranging sequence G1 according to a set period; S202, modulating the interrogation ranging sequence G1 with a first pseudo-random code to generate an interrogation signal; S203: Transmit the inquiry signal and trigger the timer to start timing.

4. The inquiry-response ranging method for rail transit applications according to claim 3, characterized in that: Step S300 includes the following sub-steps: S301: The transponder receives the interrogation signal and performs first correlation peak detection through cross-correlation calculation to obtain an interrogation signal correlation peak. S302: After detecting the interrogation signal correlation peak, generate a response ranging sequence G2 according to a set period, modulate the response ranging sequence G2 with a second pseudo-random code to generate a response signal; and add a fixed transponder signal processing delay and a random delay to the response signal for the interrogator to calculate the propagation path delay. S303: After waiting for a random delay time, the transponder sends the response signal.

5. The inquiry-response ranging method for rail transit applications according to claim 4, characterized in that: Step S301 specifically includes: after receiving and demodulating the interrogation signal, the transponder decorrelates the interrogation ranging sequence G1, and cross-correlates the transponder local code with the interrogation ranging sequence G1 to obtain a first correlation peak value. If the calculated correlation peak value exceeds a first set threshold, it is determined to be a detected interrogation signal correlation peak.

6. The inquiry-response ranging method for rail transit applications according to claim 4, characterized in that: Step S400 includes the following sub-steps: S401: The interrogator completes second correlation peak detection through cross-correlation calculation to obtain the response signal correlation peak, and triggers a timer to stop timing to obtain the time corresponding to the response signal correlation peak. S402: The interrogator calculates the measured distance based on the time corresponding to the response signal correlation peak, the interrogator signal processing fixed delay, the response signal processing fixed delay, and the random response delay.

7. The inquiry-response ranging method for rail transit applications according to claim 6, characterized in that: Step S401 specifically includes: after receiving the response signal and demodulating the response signal, the interrogator decorrelates the response ranging sequence G2, generates a pseudo-code sequence identical to the second pseudo-random code, and performs cross-correlation calculation on the pseudo-code sequence and the response ranging sequence G2 to obtain a second correlation peak value. If the calculated correlation peak value exceeds a second set threshold, it is determined to be a detected response signal correlation peak.

8. The inquiry-response ranging method for rail transit applications according to claim 1, characterized in that: The measured distance is expressed as: Where L is the measured distance, T is the time corresponding to the correlation peak of the reply signal, T1 is the fixed delay of the interrogator signal processing, T2 is the fixed delay of the transponder signal processing, T3 is the random reply delay, and c is the speed of light.

9. An electronic device, characterized in that: include: at least one processor; and a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the method according to any one of claims 1 to 8 by executing the instructions stored in the memory.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium is used to store instructions, and when the instructions are executed, the method according to any one of claims 1 to 8 is implemented.

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