LTE-M-based vehicle-mounted trunking communication host equipment, system and method

Abstract

This invention relates to an LTE-M-based vehicle-mounted trunking communication host device, system, and method. The device includes a computing processing unit, a panel interface and a status display unit connected to the computing processing unit, an LTE-M wireless communication unit, and a network switching unit. The host device connects to the vehicle-mounted PIS system and the vehicle-mounted operating terminal device via the panel interface. The network switching unit connects to the panel interface to achieve interconnection between devices. The LTE-M wireless communication unit is used for connection, registration, and network access, connects to the computing processing unit via a USB virtual serial port, and communicates with the scheduling system via the LTE-M network. This invention achieves low-cost, low-power, and highly reliable vehicle-mounted trunking scheduling communication.

Description

Technical Field

[0001] This invention relates to the field of rail transit communication technology, and in particular to an LTE-M-based vehicle trunking communication host device, system, and method. Background Technology

[0002] With the rapid development of urbanization, the construction of rail transit projects has also shown a booming growth trend. Newly constructed projects have adopted many innovative technologies. However, one of them, the dispatching trunking communication field, still relies on traditional technologies.

[0003] Wireless trunking communication is a communication system established through a wireless network to enable communication and data transmission between multiple devices within a limited geographical area. It organizes devices into a cluster or network, allowing them to communicate and collaborate. A wireless trunking communication system typically includes a cluster controller and multiple cluster members. The cluster controller manages and controls the communication and data transmission of the entire cluster, while cluster members participate in communication by establishing connections with the cluster controller. The development of trunking communication for rail transit dispatching has gone through three stages: analog trunking communication, TETRA digital trunking communication, and broadband trunking communication based on new communication technologies. Currently, broadband trunking communication based on new communication technologies is still very rare, while TETRA and analog trunking communication remain prevalent, both of which have significant drawbacks.

[0004] Analog trunking communication uses analog voice for communication and shares frequency resources by controlling channel selection through signaling. The implementation and control are relatively simple, but it also has problems such as rudimentary equipment, limited functions, poor call quality, and only being able to work in half-duplex mode. It cannot truly realize the full functions of wireless dispatching and is far from meeting the ever-growing needs of command and dispatch information transmission and integrated services.

[0005] TETRA digital trunking communication system is a professional mobile communication system based on digital time division multiple access (TDMA) technology. This system can provide multi-group scheduling functions, as well as short data message service, packet data service, and digital full-duplex mobile phone service. It makes up for the shortcomings of analog trunking communication and adds many digital communication features. However, its cost is also high, requiring dedicated high-power radio equipment, making miniaturization impossible. In addition, the interface definitions of different manufacturers are inconsistent, and the communication protocol is not open, resulting in poor interoperability. Furthermore, narrowband technology cannot support high-speed data services.

[0006] The above are currently widely used trunking communication technologies, which have problems such as high cost, poor interoperability, and limited support for data services. Summary of the Invention

[0007] The purpose of this invention is to overcome the defects of the prior art and provide an LTE-M-based vehicle trunking communication host device, system and method.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] As a first aspect of the present invention, an LTE-M-based vehicle trunking communication host device is provided, including a computing processing unit and a panel interface and status display unit connected to the computing processing unit, an LTE-M wireless communication unit and a network switching unit.

[0010] The host device is connected to the vehicle-mounted PIS system and the vehicle-mounted operation terminal device through a panel interface and a status display unit.

[0011] The network switching unit connects to the panel interface and the status display unit, and is used to achieve interconnection between devices through network switching;

[0012] The LTE-M wireless communication unit is connected to the computing processing unit via a USB virtual serial port for connection, registration and network access, and data communication with the scheduling system through the LTE-M network.

[0013] Furthermore, the panel interface of the host device and the panel interface of the status display unit include network, power and antenna interfaces;

[0014] The cluster communication host device connects to the vehicle-mounted switch and the vehicle-mounted PIS system through the network interface on the panel.

[0015] The cluster communication host device is connected to the vehicle-mounted operation terminal device through the data and power combination interface on the panel.

[0016] The cluster communication host device is connected to an antenna installed on the vehicle via an antenna interface on the panel.

[0017] Furthermore, the vehicle-mounted trunking communication host device also includes a power management unit. The host device is connected to the vehicle power supply through a power interface on the panel, and supplies power to each unit of the device after conversion by the power management unit.

[0018] Furthermore, the device also includes an RTC unit, which is connected to the computing processing unit via an I2C interface and stores the time in the hardware RTC after the device synchronizes the time over the network to provide the system time.

[0019] Furthermore, the LTE-M vehicle-mounted trunking communication host equipment is installed in the front of both ends of the train. The host equipment at both ends is connected to the vehicle-mounted switch. Both host equipment at both ends are working and send their status to the other end through the vehicle-mounted switch. When one end of the equipment fails, the other end of the equipment will immediately switch to a fully working state to achieve hot switching of primary and backup redundancy.

[0020] As a second aspect of the present invention, an LTE-M-based vehicular trunking communication system is provided, characterized in that the system comprises a terminal layer, an access layer, a core layer, and a service layer connected in sequence, each layer being interconnected with its adjacent layer but also independent, forming an LTE-M-based trunking communication network, wherein:

[0021] The terminal equipment at the terminal layer includes the LTE-M-based vehicle trunking communication host equipment and handheld operating terminals as described above.

[0022] The access layer includes base stations and antenna systems, which are used to achieve full coverage of the LTE-M network.

[0023] The core layer includes LTE-M core network equipment, which is used to implement transmission functions including connectivity, network management, and service carrying.

[0024] The business layer includes the scheduling subsystem.

[0025] Furthermore, the terminal equipment in the terminal layer also includes an in-vehicle PIS system and an in-vehicle operating terminal equipment connected to the host device.

[0026] As a third aspect of the present invention, a vehicle-mounted trunking communication method based on LTE-M is provided. The method is based on the LTE-M-based vehicle-mounted trunking communication host device described above, and specifically includes:

[0027] After the host device powers on, it retrieves and updates the current time from the RTC.

[0028] The host device sends AT commands via serial port to control the LTE-M wireless communication unit (5) to register and join the network;

[0029] After the host device successfully enters the network, it connects to the vehicle-mounted PIS and the cluster dispatch system via wired and wireless networks respectively, and enters normal working state;

[0030] The host device receives and sends voice and data messages from the PIS system and the cluster scheduling system.

[0031] Furthermore, if a disconnection or network drop occurs, the host device controls the LTE-M wireless communication unit (5) to reattach, ensuring that it is always online.

[0032] Furthermore, while the host device is in normal working condition, it maintains communication with each connected system and periodically checks, updates, and provides feedback on the host device status. When one of the host devices fails, the other host device will immediately switch to working condition to achieve redundant hot backup. When the failed device recovers, the system will return to its original working condition.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1) This invention provides an onboard host device for realizing onboard wireless trunking communication in rail transit based on LTE-M communication technology. Installed in a dedicated cabinet inside the carriage and connected to an antenna on the roof via a feeder cable, it receives wireless signals and achieves seamless access to the LTE-M core network. With the support of the LTE-M core network, the device can efficiently communicate with other dispatching equipment for voice and data. Simultaneously, the device connects to an in-vehicle switch via a network cable to communicate with the onboard PIS (Public Information System) equipment. This method and device achieve low-cost, low-power, and highly reliable onboard trunking dispatching communication.

[0035] 2) The LTE-M-based rail transit vehicle-mounted wireless trunking communication host equipment of this invention adopts a layered structure, consisting of a terminal layer, an access layer, a core layer, and a service layer. Each layer is connected to the next, and while interconnected, they also possess their own independence. This layered architecture offers high flexibility, allowing for upgrades and expansions at different levels to adapt to diverse needs; it is highly efficient, as the layered architecture distributes different functions to different levels, resulting in more efficient communication; it offers higher reliability, as the layered structure is suitable for redundancy, enhancing system reliability through redundancy techniques; and it provides good interoperability, facilitating system expansion and interconnection. Attached Figure Description

[0036] Figure 1 This is a diagram showing the unit composition of a rail transit vehicle-mounted wireless trunking communication host device based on LTE-M.

[0037] Figure 2 This is a schematic diagram of the basic system architecture of a rail transit vehicle-mounted wireless trunking communication method and host equipment based on LTE-M.

[0038] Figure 3 This is a schematic diagram illustrating the deployment of a rail transit vehicle-mounted wireless trunking communication host device based on LTE-M.

[0039] Figure 4 A flowchart illustrating the workflow of a rail transit vehicle-mounted wireless trunking communication host device based on LTE-M;

[0040] The numbers in the diagram indicate: 1. A7 core computing processing unit, 2. Panel interface and status display unit, 3. Storage unit, 4. Debugging unit, 5. LTE-M wireless communication unit, 6. RTC unit, 7. Network switching unit, 8. Power management unit. Detailed Implementation

[0041] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0042] Example 1

[0043] This invention primarily utilizes an onboard host device for wireless trunking communication in rail transit vehicles, employing a method based on LTE-M (LTE-Machine-to-Machine, an IoT technology evolved from LTE). Installed in a dedicated cabinet within the vehicle and connected to an antenna on the roof via a feeder, the device receives wireless signals and achieves seamless access to the LTE-M core network. With the support of the LTE-M core network, the device can efficiently communicate with other dispatching equipment for voice and data. Simultaneously, it connects to an in-vehicle switch via a network cable to communicate with the onboard PIS (Public Information System) equipment. This method and device achieve low-cost, low-power, and highly reliable onboard trunking dispatching communication.

[0044] like Figure 1 As shown, a rail transit vehicle-mounted wireless trunking communication host device based on LTE-M mainly consists of an A7 core computing and processing unit 1, a panel interface and status display unit 2, a storage unit 3, a debugging unit 4, an LTE-M wireless communication unit 5, an RTC unit 6, a network switching unit 7, and a power management unit 8.

[0045] The A7 core computing processing unit 1 is primarily responsible for calculating and processing data, running the ARM Linux system and dedicated software to implement application logic functions; it is the core of the entire device. The panel interface and status display unit 2 is connected to the A7 core computing processing unit 1. Its panel includes network, power, and antenna interfaces, serving as the device's external transmission path and medium. Its status display can be controlled via GPIO interface to control the flashing of lights according to system conditions. The storage unit 3 is responsible for storing all data and files, including programs, scripts, and logs. The debugging unit 4 is used for development and debugging; connecting to this unit via an RS232 serial port allows for convenient device debugging. The LTE-M wireless communication unit 5 is connected to the A7 core via a USB interface. The A7 core computing processing unit 1, which implements serial and network port functions via USB, can be controlled through its virtual network port and is a key unit for realizing LTE-M communication. The RTC unit 6 is connected to the A7 core computing processing unit 1 via an I2C interface. After the device synchronizes its time through the network, it stores the time in the hardware RTC to provide a relatively accurate system time. The network switching unit 7 connects the A7 core computing processing unit 1 and the network port on the panel, providing network switching functionality to facilitate interconnection between devices. The power management unit 8 connects to all other units, providing power to the overall system and performing power management.

[0046] As a second embodiment of the present invention, a system of LTE-M-based on-board wireless trunking communication host equipment and its communication method for rail transit is provided, the basic architecture of which is shown in the schematic diagram below. Figure 2As shown, a layered structure is adopted, comprising four main layers from bottom to top: terminal layer, access layer, core layer, and service layer. Each layer connects to the next, and while interconnected, each layer maintains its own independence. This layered architecture offers high flexibility, allowing upgrades and expansions at different levels to adapt to diverse needs; it is efficient, as the layered architecture distributes different functions across different layers, resulting in more efficient communication; it offers higher reliability, as the layered structure is suitable for redundancy, enhancing system reliability; and it provides good interoperability, facilitating system expansion and interconnection. Different layers implement different functions. The terminal layer includes various terminal devices, which can be fixed, vehicle-mounted, or mobile. The device described in this invention is a vehicle-mounted "LTE-M vehicle-mounted host device," installed in a cabinet within the train carriage. It establishes a connection with the LTE-M core network via a roof-mounted antenna, thereby accessing the entire dispatch system. The access layer includes base stations and antenna systems, utilizing omnidirectional antennas, directional antennas, leaky cables, and indoor distribution systems to achieve full-area coverage, enabling seamless terminal access and switching. The core layer consists of LTE-M core network equipment, responsible for core transmission functions such as connectivity, network management, and service delivery. Together with the access layer, it forms a bridge connecting the service layer and the terminal layer. The service layer contains various application implementation subsystems; the one relevant to the "LTE-M vehicle-mounted host equipment" of this invention is the scheduling subsystem.

[0047] Example 2

[0048] As one specific implementation example of the present invention, the LTE-M-based rail transit vehicle-mounted wireless trunking communication method and host equipment in this embodiment achieves communication transmission with the dispatching system by installing the LTE-M vehicle-mounted host equipment on a dedicated cabinet in the train carriage and connecting to the LTE-M core network through the antenna on the roof of the vehicle. The method and equipment realize low-cost, low-power, and highly reliable vehicle-mounted trunking dispatching communication.

[0049] like Figure 2 The diagram illustrates the basic system architecture of a rail transit vehicle-mounted wireless trunking communication method and host equipment based on LTE-M. This structure employs a flat, layered approach, comprising four layers: a terminal layer, an access layer, a core layer, and a service layer. Each layer is interconnected with its neighboring layers yet maintains independence, collectively forming an LTE-M-based trunking communication network. Closely related to dispatch communication are the LTE-M vehicle-mounted host equipment and handheld operating terminals located in the terminal layer, and the dispatch server and dispatch console located in the service layer. These components establish connections and communicate with each other through the LTE-M core network.

[0050] The specific device models used in each unit of this wireless trunking communication host equipment are as follows: A7 core computing processing unit 1: MCIMX6Y2CVM05AB; panel interface and status display unit 2: NUP2202W1T2G, WX384HKEY; storage unit 3: NT5CC256M16ER-EK, KLM8G1GETF; debugging unit 4: CP2102; LTE-M wireless communication unit 5: CX630x; RTC unit 6: DS1337S; network switching unit 7: KSZ8999I; power management unit 8: YHD100-110S13V8T-OF.

[0051] The power interface on the device's panel connects to the vehicle's AC 220V power supply, which, after conversion by the power management unit 8, powers each unit of the device. The 100Mbps Ethernet interface on the panel connects to the vehicle's switch and the vehicle's PIS system, while the data-power combination interface connects to the operating terminal device. The LTE-M wireless communication unit 5 connects to the A7 core computing processing unit 1 via a USB virtual serial port. The A7 core computing processing unit 1 sends specific AT commands to the LTE-M wireless unit to control its connection, registration, and network access. The LTE-M wireless unit then returns the execution results to the A7 core computing processing unit 1 via the virtual serial port. Upon receiving a successful network access message, it indicates that a data connection can be established, and scheduling data is then transmitted and received through the LTE-M wireless unit's network port. This device uses LTE-M for communication, offering superior call quality compared to analog and TRTRA technologies, a more compact form factor, lower cost, and more flexible expansion capabilities, achieving optimal performance while meeting specific requirements.

[0052] The deployment method of the LTE-M-based on-board wireless trunking communication host equipment on the train is as follows: Figure 3 As shown, this is a typical deployment configuration. The LTE-M onboard host equipment is installed on racks inside the TC1 and TC2 locomotives at both ends of the train, with one unit installed at each end. When the train turns around, the equipment at the other end can be used. Both ends are connected to the onboard switch, and both ends operate, sending their status information to the other end via the switch. If the TC1 end equipment fails, the TC2 end equipment immediately switches to full operational status, achieving hot-switching for redundancy and significantly improving system security. The equipment also connects to an omnidirectional antenna on the roof via an antenna interface on the panel. The antenna supports full-band signals such as 800MHz, 900MHz, 1800MHz, and 2100MHz, wirelessly accessing the LTE-M core network and establishing a connection with the dispatching system.

[0053] In this embodiment, the main working process of a rail transit vehicle-mounted wireless trunking communication host device based on LTE-M is as follows: Figure 4 As shown, the device runs an ARM Linux system and dedicated scheduling and communication software. After powering on, it first obtains the current time from the RTC and updates it to the system. Then, it sends AT commands via serial port to control the LTE-M wireless module to register and join the network. If a disconnection or network drop occurs, it controls the LTE-M wireless module to reattach, ensuring a constant online state. After successfully joining the network, it soft-connects to the vehicle-mounted PIS and the cluster dispatch system via wired and wireless networks respectively. At this point, it enters normal working state and can receive and send voice and data messages from the PIS system and the cluster dispatch system. Simultaneously, the device maintains communication with each connected system and periodically checks, updates, and reports its status. When a device at one end fails, the other end immediately switches to full working state, achieving redundant hot backup. When the failed device recovers, the system reverts to its original working state.

[0054] Compared with existing vehicle-mounted simulation and TETRA trunking communication equipment and technologies, the technical solution of this invention includes the following innovations and beneficial effects.

[0055] 1. Existing vehicle-mounted analog trunking communication equipment uses analog voice communication, which suffers from problems such as rudimentary equipment, limited functionality, and poor call quality. In contrast, this invention uses digital communication, offering richer functionality. Through encrypted transmission technology, it effectively improves data security and significantly increases system capacity, meeting more connection needs. Furthermore, this invention provides higher-quality full-duplex calls, offering a superior service for vehicle-mounted communication.

[0056] 2. While vehicle-mounted TETRA trunking communication equipment solves some problems of analog trunking communication, it also suffers from high costs, poor interoperability, and lack of support for high-speed data services. Compared to TETRA trunking communication equipment, this invention utilizes the latest LTE-M technology, resulting in a smaller communication module and consequently, a smaller vehicle-mounted host device with lower power consumption. Furthermore, this device offers excellent scalability and easy interoperability with other devices, while also being more cost-effective overall. Moreover, due to the characteristics of LTE-M technology, this device supports high-speed data services, such as video intercom and large data transmissions, meeting the ever-growing demands of command and dispatch information transmission and integrated services.

[0057] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A vehicle-mounted trunking communication host device based on LTE-M, characterized in that, It includes a computing processing unit (1) and a panel interface and status display unit (2) connected to the computing processing unit (1), an LTE-M wireless communication unit (5) and a network switching unit (7). The host device is connected to the vehicle-mounted PIS system and the vehicle-mounted operation terminal device through the panel interface and status display unit (2); the panel interface of the host device and the panel interface of the status display unit (2) include network, power and antenna interfaces. The trunking communication host device connects to the vehicle-mounted switch and the vehicle-mounted PIS system through the network interface on the panel; the trunking communication host device connects to the vehicle-mounted operating terminal device through the data and power combination interface on the panel; the trunking communication host device connects to the antenna installed on the vehicle through the antenna interface on the panel. The network switching unit (7) is connected to the panel interface and the status display unit (2) and is used to realize the interconnection between devices through network switching; The LTE-M wireless communication unit (5) is connected to the computing processing unit (1) via a USB virtual serial port for connection, registration and network access, and is connected to the scheduling system for data communication via the LTE-M network; The device also includes an RTC unit (6), which is connected to the computing processing unit (1) via an I2C interface and stores the time in the hardware RTC after the device synchronizes the time via the network to provide system time.

2. The LTE-M-based vehicle trunking communication host device according to claim 1, characterized in that, The vehicle-mounted trunking communication host device also includes a power management unit (8). The host device is connected to the vehicle power supply through the power interface on the panel, and supplies power to each unit of the device after conversion by the power management unit (8).

3. The LTE-M-based vehicle trunking communication host device according to claim 1, characterized in that, The LTE-M vehicle-mounted trunking communication host equipment is installed in the front of both ends of the train. The host equipment at both ends is connected to the vehicle-mounted switch. Both host equipment are working and send their status to the other end through the vehicle-mounted switch. When one end of the equipment fails, the other end of the equipment will immediately switch to a fully working state to achieve hot switching of primary and backup redundancy.

4. A vehicle-mounted trunking communication system based on LTE-M, characterized in that, The system comprises a terminal layer, an access layer, a core layer, and a service layer connected in sequence. Each layer is interconnected with its adjacent layers but also has independence, forming a trunking communication network based on LTE-M, wherein: The terminal equipment at the terminal layer includes the LTE-M-based vehicle trunking communication host equipment and the handheld operating terminal as described in any one of claims 1-3; The access layer includes base stations and antenna systems, which are used to achieve full coverage of the LTE-M network. The core layer includes LTE-M core network equipment, which is used to implement transmission functions including connectivity, network management, and service carrying. The business layer includes the scheduling subsystem.

5. A vehicle-mounted trunking communication system based on LTE-M according to claim 4, characterized in that, The terminal equipment in the terminal layer also includes an in-vehicle PIS system and an in-vehicle operation terminal equipment connected to the host device.

6. A vehicle-mounted trunking communication method based on LTE-M, characterized in that, The method is based on the LTE-M-based vehicle trunking communication host equipment as described in any one of claims 1-3, and the method specifically includes: After the host device powers on, it retrieves and updates the current time from the RTC. The host device sends AT commands via serial port to control the LTE-M wireless communication unit (5) to register and join the network; After the host device successfully enters the network, it connects to the vehicle-mounted PIS and the cluster dispatch system via wired and wireless networks respectively, and enters normal working state; The host device receives and sends voice and data messages from the PIS system and the cluster scheduling system.

7. A vehicle-mounted trunking communication method based on LTE-M according to claim 6, characterized in that, If a disconnection or network drop occurs, the host device controls the LTE-M wireless communication unit (5) to reattach, ensuring that it is always online.

8. A vehicle-mounted trunking communication method based on LTE-M according to claim 6, characterized in that, While the host device is in normal working condition, it maintains communication with each connected system and periodically checks, updates and provides feedback on the host device status. When one of the host devices fails, the other host device will immediately switch to working condition to achieve redundant hot backup. When the failed device recovers, the system will return to its original working condition.

Images