A method for forwarding train-ground communication data and a communication unit

Abstract

The present invention provides a method for forwarding vehicle-ground communication data and a communication unit. The forwarding method includes: acquiring the original data of vehicle-ground communication; copying the original data and using the copied original data as the forwarding data; obtaining the forwarding structure to be forwarded based on the forwarding data; and generating a forwarding data packet based on the forwarding structure to be forwarded. The present invention efficiently realizes the data forwarding in vehicle-ground communication.

Description

Technical Field

[0001] The present invention belongs to the field of communication technologies in rail transit train operation control systems, and particularly relates to a method for forwarding vehicle-ground communication data and a communication unit. Background Art

[0002] In a rail transit train operation control system (hereinafter referred to as a train control system), on-vehicle equipment realizes vehicle-ground communication through point-type balises laid on the ground or wireless networks (such as GSM-R / GPRS / LTE, etc.). The former is non-continuous communication, while the latter can achieve continuous vehicle-ground communication. The on-vehicle equipment relies on the necessary data obtained through vehicle-ground communication to achieve safe and efficient train operation. Therefore, the vehicle-ground communication function is one of the core important functions of on-vehicle equipment. However, due to the large overall software scale of on-vehicle equipment, concentrated equipment functions, and high hardware performance requirements, it poses great challenges for software maintenance, problem troubleshooting, and software changes. Summary of the Invention

[0003] In view of the above problems, the present invention provides a method for forwarding vehicle-ground communication data, and the forwarding method includes:

[0004] Obtain the original data of vehicle-ground communication;

[0005] Copy the original data, and use the copied original data as the forwarding data;

[0006] According to the forwarding data, obtain the forwarding structure to be forwarded;

[0007] Generate a forwarding data packet according to the forwarding structure to be forwarded.

[0008] Further, obtaining the forwarding structure to be forwarded according to the forwarding data includes:

[0009] Generate an initial forwarding structure according to the forwarding data;

[0010] Obtain the forwarding structure to be forwarded according to the initial forwarding structure.

[0011] Further, generating an initial forwarding structure according to the forwarding data includes:

[0012] Calculate the bit start offset of the forwarding data, and index to the byte where the end of the bit stream in the forwarding data is located;

[0013] Copy the content of the byte where the end of the bit stream is located from the forwarding data as a whole, and generate an initial forwarding structure.

[0014] Further, obtaining the forwarding structure to be forwarded according to the initial forwarding structure includes:

[0015] Push the initial forwarding structure into the forwarding queue;

[0016] Obtain the forwarding structure to be forwarded from the forwarding queue according to preset conditions.

[0017] Furthermore, when pushing the initial forwarding structure into the forwarding queue, calculate the checksum of the initial forwarding structure.

[0018] Furthermore, before obtaining the forwarding structure to be forwarded from the forwarding queue, check the checksum of the initial forwarding structure.

[0019] Furthermore, the information included in the initial forwarding structure includes an identifier, a sequence number, a bit offset, a bit length, a data buffer, and a checksum.

[0020] Furthermore, the information included in the forwarding data packet includes a data packet header and a data packet content.

[0021] Furthermore, the data packet header includes a header identifier field, a packet length field, a bit offset field, and a bit length field.

[0022] Furthermore, the packet length indicating the length of the entire data forwarding packet is an optional field.

[0023] Furthermore, the data packet content is a forwarding data buffer.

[0024] On the other hand, the present invention also provides a communication unit, including:

[0025] A raw data acquisition module for acquiring the raw data of vehicle-ground communication;

[0026] A copy module for copying the raw data and using the copied raw data as forwarding data;

[0027] A forwarding data acquisition module for obtaining the forwarding structure to be forwarded according to the forwarding data;

[0028] A forwarding data packet generation module for generating a forwarding data packet according to the forwarding structure to be forwarded.

[0029] Furthermore, obtaining the forwarding structure to be forwarded according to the forwarding data includes:

[0030] Generate an initial forwarding structure according to the forwarding data;

[0031] Obtain the forwarding structure to be forwarded according to the initial forwarding structure.

[0032] Furthermore, generating an initial forwarding structure according to the forwarding data includes:

[0033] Calculate the bit start offset of the forwarding data and index to the byte where the end of the bit stream in the forwarding data is located;

[0034] Overall copy the content of the byte where the end of the bitstream is located from the forwarded data, and generate an initial forwarding structure.

[0035] Further, according to the initial forwarding structure, obtaining the forwarding structure to be forwarded includes:

[0036] Push the initial forwarding structure into the forwarding queue;

[0037] According to preset conditions, obtain the forwarding structure to be forwarded from the forwarding queue.

[0038] The present invention provides a method and a communication unit for forwarding vehicle-ground communication data, which lay a foundation for separating the vehicle-ground communication function from the on-vehicle core device while meeting vehicle-ground secure communication, and provide support for reducing the maintenance difficulty of on-vehicle devices.

[0039] Other features and advantages of the present invention will be described in the following specification, and some of them will become obvious from the specification, or be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures pointed out in the specification, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0041] Figure 1 Shows a flowchart of the forwarding method according to an embodiment of the present invention.

[0042] Figure 2 Shows a schematic diagram of the generation of the forwarding structure according to an embodiment of the present invention.

[0043] Figure 3 Shows a schematic diagram of the forwarding structure according to an embodiment of the present invention.

[0044] Figure 4 Shows a schematic diagram of the vehicle-ground communication structure according to an embodiment of the present invention.

[0045] Figure 5 Shows a schematic diagram of the communication structure for implementing a common communication channel according to an embodiment of the present invention.

[0046] Figure 6 Shows a step diagram of the forwarding method according to an embodiment of the present invention.

[0047] Figure 7 Shows a schematic diagram of the current vehicle-ground communication system structure. Specific Embodiments

[0048] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] In a train control system, generally, while the core control part in on-vehicle equipment needs to complete logical functions, it also needs to be responsible for functions such as vehicle-ground communication session maintenance and data processing, resulting in a relatively large overall software scale and function integration, which poses certain difficulties for software maintenance and problem troubleshooting. With the continuous development of the train control system, as the ultimate "decision maker" of the entire system, on-vehicle equipment will surely undertake more and more complex function implementations. It is an inevitable trend to achieve function decentralization and distribution through data forwarding, which is also conducive to the implementation of new functions and reduces the impact brought by software coupling.

[0050] Therefore, as Figure 1 shown, the present invention provides a method for forwarding vehicle-ground communication data, and the forwarding method includes:

[0051] Obtain the original data of vehicle-ground communication;

[0052] Copy the original data, and use the copied original data as the forwarding data;

[0053] Obtain the forwarding structure to be forwarded according to the forwarding data;

[0054] Generate a forwarding data packet according to the forwarding structure to be forwarded.

[0055] The following is a detailed description:

[0056] The original data of vehicle-ground communication in this embodiment refers to the data sent by ground equipment or the data sent by on-vehicle equipment.

[0057] After obtaining the original data, first copy a copy of the original data, use the copied original data as the forwarding data, and do not process the original original data. Only process the copied forwarding data, and the processing steps are as follows:

[0058] Generate an initial forwarding structure according to the forwarding data, as Figure 2 shown, specifically:

[0059] Calculate the bit start offset of the forwarding data, and index to the byte where the end of the bit stream in the forwarding data is located;

[0060] Overall copy the content of the byte where the end of the bitstream is located (the part to be forwarded) from the forwarded data, generate an initial forwarding structure, and calculate the checksum of this forwarding structure;

[0061] According to the initial forwarding structure, obtain the forwarding structure to be forwarded. Specifically:

[0062] Push the initial forwarding structure after calculating the checksum into the forwarding queue and wait to be extracted. Among them, before pushing the initial forwarding structure after calculating the checksum into the forwarding queue, it is necessary to judge whether the forwarding queue is full. If it is full, error handling is performed (that is, record the failure of the forwarding queue being full and perform artificial failure handling). If it is not full, the initial forwarding structure after calculating the checksum is pushed into the forwarding queue.

[0063] According to the preset conditions (that is, according to the processing capacity and processing situation. For example, as a forwarding channel for data forwarding, there is a data size limit. For example, at most 500 bytes of data can pass through. Then, if the forwarding structure occupies 300 bytes and the other data to be forwarded together occupies more than 200 bytes, then the forwarding structure is not forwarded at this time. When the other data to be forwarded together occupies 200 bytes or less next time, the forwarding structure is forwarded), extract the initial forwarding structure.

[0064] Before extracting the initial forwarding structure, it is necessary to judge whether the forwarding queue is empty. If it is not empty, pop the initial forwarding structure and use this forwarding structure as the forwarding structure to be forwarded (if it is empty, the initial forwarding structure is not popped). Then check whether the checksum of the forwarding structure to be forwarded is correct. Among them, if the checksum of the forwarding structure to be forwarded is incorrect (such as by checking the checksum, it can be judged whether the data in the forwarding structure pushed into the queue has been modified), error handling is performed (that is, record the failure of the incorrect checksum of the forwarding structure to be forwarded and perform artificial failure handling). If it is correct, it is also necessary to judge whether the sequence number in the forwarding structure to be forwarded (the sequence number is described below) meets the expectation. If it does not meet, error handling is performed (that is, record the failure of the sequence number of the forwarding structure to be forwarded not meeting the expectation and perform artificial failure handling). If it meets, generate a forwarding data packet according to the forwarding structure to be forwarded and send it to the object to be forwarded.

[0065] After the initial forwarding structure is pushed into the forwarding queue, it waits to be extracted ( Figure 6) is equivalent to a storage process. The process of obtaining the forwarding structure to be forwarded is an acquisition process obtained according to requirements. Therefore, the entire data forwarding process is a typical "producer-consumer" model. During the whole process, only reading and copying operations are performed on the original data, and when it is not a periodic operation, security protection is carried out through checksums, avoiding accidental errors caused by memory corruption, etc., meeting the requirements of signal software security coding. And it directly copies the part to be forwarded from the "forwarding data" as a whole by bytes. The advantage of directly forwarding without parsing the content of the original data is to avoid possible "pollution" of security data, and only the final data receiver performs data parsing in the whole processing flow, reducing software complexity and reducing processing failure points.

[0066] The following is an explanation of the initial forwarding structure:

[0067] The high reliability of the train control system often requires not to adopt the latest hardware products. In order to make more effective use of the hardware performance, relevant domestic and foreign standards are more demanding in the design of communication protocols and formats, generally designed according to bits. In order to meet the complexity of vehicle-ground wireless communication messages, the forwarding structure is designed to operate based on bit streams. And considering the reliability of security data forwarding, no operation is performed on the existing data and CRC (Cyclic Redundancy Check) is calculated for verification. A basic forwarding structure can be defined as shown in Table 1 below:

[0068]

[0069] Table 1

[0070] It should be noted that the ranges of the identifier (nid), sequence number (seq), and bit length (bitLen) should be determined according to specific requirements, and the size of a similar data buffer (bitBuff) should also meet the forwarding requirements.

[0071] Without loss of generality, Figure 3 is an actual example of a forwarding structure. In the figure, the entire array buffer is the data buffer = 2 Byte, and the forwarding data starts from the bit offset = 6, with a bit length = 7 bit. This section of data is identified as 121 and is the 15th forwarding structure.

[0072] There are many calculation methods for checksums, such as parity check, CRC check, etc. They can be used as needed but must include all the information of the above forwarding structure to uniquely determine this forwarding structure.

[0073] For the forwarded data packet, the sequence number and checksum are only used internally within the communication unit, and other parts do not process them. Instead, they are handed over to the data receiver (such as ground equipment, vehicle-mounted equipment, or other equipment) for processing. The forwarded data packet should contain as much necessary information as possible. The information contained in the forwarded data packet includes the data packet header and the data packet content. The data packet header includes four fields: packet header identifier (NID_PACKET), packet length (L_PACKET), T-bit offset (BIT_OFFSE), and bit length (BIT_LEN). Among them, L_PACKET represents the length of the entire forwarded data packet and is an optional field used to skip this forwarded data packet during parsing. The content of the forwarded data packet is the copied forwarded data buffer, and the expression structure is as shown in Table 2 below (Table 2 is the protocol format table for the forwarded data packet):

[0074]

[0075] Table 2

[0076] The present invention also provides a communication unit, including:

[0077] An original data acquisition module for acquiring the original data of vehicle-ground communication;

[0078] A copy module for copying the original data and using the copied original data as the forwarded data;

[0079] A to-be-forwarded data acquisition module for acquiring the to-be-forwarded forwarding structure based on the forwarded data;

[0080] A forwarded data packet generation module for generating a forwarded data packet based on the to-be-forwarded forwarding structure.

[0081] Further, acquiring the to-be-forwarded forwarding structure based on the forwarded data includes:

[0082] Generating an initial forwarding structure based on the forwarded data;

[0083] Acquiring the to-be-forwarded forwarding structure based on the initial forwarding structure.

[0084] Further, generating an initial forwarding structure based on the forwarded data includes:

[0085] Calculating the bit start offset of the forwarded data and indexing to the byte where the end of the bit stream in the forwarded data is located;

[0086] Copying the content of the byte where the end of the bit stream is located from the forwarded data as a whole and generating an initial forwarding structure.

[0087] Further, acquiring the to-be-forwarded forwarding structure based on the initial forwarding structure includes:

[0088] Pushing the initial forwarding structure into the forwarding queue;

[0089] Obtain the forwarding structure to be forwarded from the forwarding queue according to preset conditions.

[0090] The forwarding object required by the forwarding method of the present invention is an on-vehicle device or a ground device. Without loss of generality, the implementation device for implementing the forwarding method of the present invention is referred to as a communication unit, such as Figure 4 As shown, it is a schematic structural diagram of data forwarding of the communication unit.

[0091] The communication unit splits the data received from the ground device (that is, calculates the bit start offset of the forwarded data, indexes to the byte where the end of the bit stream in the forwarded data is located, and copies the content of the byte where the end of the bit stream is located from the forwarded data as a whole), forms a general forwarding structure, and finally forwards it to the on-vehicle device for forwarding the data packet ( Figure 4 ). The communication unit can also forward the forwarding data packet to other devices, and the communication unit can be used as a common communication channel ( Figure 5 ).

[0092] Such as Figure 7 As shown, in the existing vehicle-ground communication, by parsing the data of the vehicle-ground communication, the parsed data is repackaged and sent to the corresponding device, or the original data is directly packaged and sent. In this way, either the forwarded data is invaded, or the necessary data cannot be flexibly forwarded. And if the vehicle-ground communication capability needs to be reused, only the code can be reused, and the structure and logic of the vehicle-ground communication cannot be simplified through data forwarding. In this embodiment, through the provided communication unit, the data forwarding in the vehicle-ground communication is realized.

[0093] Moreover, in this embodiment, the forwarding structure, forwarding mechanism, and byte stream can well adapt to the communication format characteristics of the train control system, support flexible and efficient bit stream forwarding, do not process the original data, and add a checksum, meeting the programming requirements of the signal safety software.

[0094] In addition, in the design of the format of the forwarding data packet, the user can embed the protocol format of the forwarding data packet in this embodiment into its own protocol, and the order, fields, and number of bits can all be processed and customized as needed.

[0095] In addition, other functions implemented by a communication unit of the present invention and the implementation manners are correspondingly consistent with the functions and implementation manners of other steps in a method for forwarding vehicle-ground communication data of the present invention. Therefore, they will not be elaborated here.

[0096] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments of equivalent changes within the scope of the technical solution of the present invention by using the technical content disclosed above. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for forwarding vehicle-ground communication data, characterized in that The forwarding method includes: In the train operation control system of rail transit, obtain the original data of vehicle-ground communication; Copy the original data, and use the copied original data as the forwarding data; According to the forwarding data, obtain the forwarding structure to be forwarded; Generate a forwarding data packet according to the forwarding structure to be forwarded; According to the forwarding data, obtaining the forwarding structure to be forwarded includes: Generate an initial forwarding structure according to the forwarding data; Obtain the forwarding structure to be forwarded according to the initial forwarding structure; Generating an initial forwarding structure according to the forwarding data includes: Calculate the bit start offset of the forwarding data, and index to the byte where the end of the bit stream in the forwarding data is located; Copy the content of the byte where the end of the bit stream is located from the forwarding data as a whole, and generate an initial forwarding structure; According to the initial forwarding structure, obtaining the forwarding structure to be forwarded includes: Push the initial forwarding structure into the forwarding queue; According to preset conditions, obtain the forwarding structure to be forwarded from the forwarding queue; When pushing the initial forwarding structure into the forwarding queue, calculate the checksum of the initial forwarding structure; Before obtaining the forwarding structure to be forwarded from the forwarding queue, check the checksum of the initial forwarding structure; The information included in the initial forwarding structure includes identification, sequence number, bit offset, bit length, data buffer, and checksum.

2. The forwarding method of in-vehicle and ground communication data according to claim 1, characterized in that The information included in the forwarding data packet includes a data packet header and a data packet content.

3. The forwarding method of in-vehicle and ground communication data according to claim 2, wherein The data packet header includes a header identification field, a packet length field, a bit offset field, and a bit length field.

4. The method for forwarding train-ground communication data according to claim 3, wherein The packet length represents the length of the entire data forwarding packet, and is an optional field.

5. A method for forwarding vehicle-ground communication data according to claim 3, characterized in that The data packet content is a forwarding data buffer.

6. A communication unit, characterized in that, Includes: An original data acquisition module, which is used to obtain the original data of vehicle-ground communication in the train operation control system of rail transit; A copy module, which is used to copy the original data and use the copied original data as the forwarding data; A module for obtaining data to be forwarded, which is used to obtain the forwarding structure to be forwarded according to the forwarding data; A forwarding data packet generation module, which is used to generate a forwarding data packet according to the forwarding structure to be forwarded; According to the forwarding data, obtaining the forwarding structure to be forwarded includes: Generate an initial forwarding structure according to the forwarding data; Obtain the forwarding structure to be forwarded according to the initial forwarding structure; Generating an initial forwarding structure according to the forwarding data includes: Calculate the bit start offset of the forwarding data, and index to the byte where the end of the bit stream in the forwarding data is located; Copy the content of the byte where the end of the bit stream is located from the forwarding data as a whole, and generate an initial forwarding structure; According to the initial forwarding structure, obtaining the forwarding structure to be forwarded includes: Push the initial forwarding structure into the forwarding queue; According to preset conditions, obtain the forwarding structure to be forwarded from the forwarding queue; When pushing the initial forwarding structure into the forwarding queue, calculate the checksum of the initial forwarding structure; Before obtaining the forwarding structure to be forwarded from the forwarding queue, check the checksum of the initial forwarding structure; The information included in the initial forwarding structure includes identification, sequence number, bit offset, bit length, data buffer, and checksum.

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