Method and system for transmitting data between vehicle and data processing center in multi-channel wireless network

Abstract

FIELD: wireless communication.SUBSTANCE: method comprises: transmitting service and user packets via radio channels between a vehicle router and wireless communication nodes; relaying service and user packets to nodal switches; receiving packet copies by the nodal switches and selecting one of them; updating a table of correspondences between the L2 addresses of the vehicle router and the nodal switch on the nodal switches upon receiving the selected copy of the service packet; generating aggregated service packets comprising the addresses of the nodal switch and the vehicle router, and transmitting the aggregated service packets to a data processing centre (DPC) router; dynamically updating the switching table on the DPC router, the switching table establishes a correspondence between the L2 addresses of the vehicle router and the nodal switch from which the aggregated service packet was last received; transmitting user packets from the DPC router to the vehicle router via the nodal switch, the address of which corresponds to the address of the vehicle router in the switching table.EFFECT: reduction in delays and an increase in the stability of data transmission.16 cl, 4 dwg

Description

[0001] Technical field

[0002] The invention relates to the field of wireless communications and, in particular, to methods and systems for transmitting data between moving vehicles and stationary ground infrastructure. Specifically, the invention relates to communication systems designed to ensure high-speed data transmission while the vehicle is moving at high speed, including train-to-ground systems.

[0003] Technology Level

[0004] A wireless communication system for a vehicle with a terrestrial network is known, disclosed in U.S. Patent US 11304038 B2 (publication date: 02.09.2021, IPC H04W 4 / 00, H04W 76 / 10, H04W 16 / 28). The known system includes a vehicle containing several wireless modems and a plurality of wireless access points that are part of a fixed network. Each access point is equipped with a directional antenna system and is designed to exchange data with the vehicle's wireless modems via a millimeter-wave radio channel using steerable directional beams.

[0005] The vehicle's wireless modems are capable of establishing radio communication with access points. The vehicle generates and transmits service messages to the ground network containing information about the mapping of the wireless modems' MAC addresses to the vehicle identifier. These service messages are used by the access points to manage access scheduling to the radio interface at the channel access layer (MAC scheduling).

[0006] The access points are configured to exchange the specified service information with each other to coordinate MAC scheduling parameters and distribute radio resources when transmitting data between the vehicle and the ground network.

[0007] The disadvantage of the known solution is that when the vehicle moves, the transmission of user data is accompanied by an increase in delays and a decrease in communication stability due to the dependence of the data transmission process on the procedures for scheduling access to the radio interface and managing radio resources on the access point side.

[0008] The indicated drawback is due to the fact that in the known system, the transmission of user data is carried out within the framework of controlled access to the radio channel, in which access points perform data transmission planning at the MAC level taking into account service information about the state of radio lines, the parameters of directional beams and the activity of wireless modems of the vehicle.

[0009] When radio access conditions change due to vehicle movement, it is necessary to update service information and restructure MAC scheduling and radio resource allocation parameters, which results in additional delays and increases the system sensitivity to radio channel dynamics during high-speed movement.

[0010] A wireless communication system between a moving vehicle and a ground network is known, disclosed in U.S. Patent US 10236944 B2 (publication date: July 27, 2017, IPC H04B 7 / 26, H04W 4 / 02). The known system includes a vehicle with multiple transceivers and ground network base stations located along the vehicle's route. User data is transmitted via a radio channel established between a selected radio transceiver of the vehicle and a radio transceiver of the base station.

[0011] For the active radio transceiver, the radio channel parameters associated with the vehicle's current position relative to the base station are determined. As the vehicle moves, another radio transceiver within the base station's radio coverage area is identified and information about the radio channel parameters is transmitted to it in preparation for establishing or maintaining communication. The radio channel is used for data transmission based on these radio channel parameters.

[0012] The system provides for the exchange of service information related to radio channel parameters, vehicle movement and the location of radio transceivers, used to control the processes of establishing, maintaining and switching radio communication channels between the vehicle and the ground network.

[0013] The disadvantage of the known solution is that when the vehicle is moving, the transmission of user data is carried out with increased delays and is accompanied by the risk of reducing the stability of the communication channel, especially when changing the active radio transceiver when moving between radio coverage areas of base stations.

[0014] These shortcomings arise from the fact that in the known system, user data transmission is functionally tied to the established radio channel between the selected vehicle radio transceiver and the ground network radio transceiver. When the vehicle moves, a sequence of service operations is required, including determining the radio channel parameters, identifying the next radio transceiver, transmitting the radio channel parameters to it, and using these parameters to establish or maintain communication.

[0015] The execution of the specified operations takes time and depends on the quality of the radio communication and the correctness of the exchange of service information, as a result of which, during the process of switching the active radio transceiver, time intervals arise during which the transmission of user data is carried out with increased delays or with reduced stability, or with data loss at the network and / or transport layers.

[0016] A wireless communication system for a moving vehicle with a ground network is known, disclosed in U.S. Patent US 10194308 B2 (Publication date 04.10.2018, IPC H04W 8 / 02, H04W 12 / 06, H04W 76 / 10). The system includes a vehicle and a plurality of wireless access points located along the vehicle's route. The vehicle comprises at least two wireless bridge devices configured to establish radio communication with the access points. Said bridge devices are interconnected via a wired communication line and interact through an onboard switch.

[0017] The onboard switch is capable of duplicating user data packets and transmitting copies of these packets to various wireless bridge devices. Each bridge device transmits the received packet over its own radio channel to the corresponding access point, resulting in the same user traffic being transmitted over multiple wireless channels.

[0018] Heartbeat messages are exchanged between onboard bridge devices. These messages are used to exchange information about the state of radio channels and to coordinate the execution of roaming and handover procedures, including controlled switching of bridge devices between access points with the coordination of connection states.

[0019] When transmitting data in a terrestrial network, network identifiers are added to user packets. These identifiers are used by intermediate and aggregation network nodes to process the packets and determine their subsequent transmission direction. The terrestrial portion of the system includes a mechanism for eliminating duplicate user packets received over different wireless channels.

[0020] A drawback of the existing solution is that when a vehicle is moving, user data transmission is subject to increased latency, leading to the risk of communication channel instability when moving between the coverage areas of different access points. These drawbacks stem from the fact that maintaining continuous communication in the existing system relies on a roaming procedure, which requires time for service exchange and connection state processing, during which time user data transmission is delayed or temporarily degraded.

[0021] Further instability in data transmission is exacerbated by the fact that the direction of user packets in the terrestrial network is determined based on network identifiers processed by intermediate and aggregation network nodes. When the traffic entry point changes due to vehicle movement, the packet transmission direction must be adjusted, increasing the system's sensitivity to network processing delays and reducing the stability of the end-to-end connection during high-speed travel.

[0022] The technical problem that the claimed invention is aimed at solving is ensuring continuous and stable transmission of user data between a moving vehicle and a ground network with low delays and maintaining the quality of service when the vehicle moves between wireless communication nodes.

[0023] Disclosure of the essence of the invention

[0024] The technical result achieved by the claimed group of inventions consists in reducing delays and increasing the stability of the transmission of user data during high-speed movement of a vehicle in the coverage area of ​​a distributed network of wireless communication nodes.

[0025] The invention claims a method for transmitting data between a vehicle and a data processing center (DPC) in a multi-channel wireless network. The claimed method comprises the following steps:

[0026] - transmission of service and user packets over at least two radio channels between a vehicle router and at least two wireless communication nodes located along the vehicle route, wherein the vehicle router has a unique L2 address, and the service packets contain at least the specified address;

[0027] - retransmission of service and user packets received by wireless communication nodes to nodal switches connected to wireless communication nodes that carry out radio communication with the vehicle router;

[0028] - reception at each of the specified nodal switches of all copies of the same packet received from different wireless communication nodes, and selection of one of the received copies for further transmission;

[0029] - updating the correspondence table on each nodal switch based on the received service packets selected from the received copies, wherein the correspondence table establishes a correspondence between the L2 address of the vehicle router and the L2 address of this nodal switch upon receipt of the selected copy of the service packet;

[0030] - generation at each nodal switch receiving service packets from the vehicle router of aggregated service packets containing the L2 address of the specified nodal switch and the L2 address of the vehicle router associated with it, and transmission of the aggregated service packets to the data center router;

[0031] - dynamically updating the switching table on the data center router based on aggregated service packets, wherein the switching table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the node switch from which the aggregated service packet was last received; and

[0032] - transmitting user packets from the data center router to the vehicle router through the nodal switch whose L2 address matches the L2 address of the vehicle router in the switching table on the data center router.

[0033] The claimed method for transmitting data between a vehicle and a data center in a multi-channel wireless network can be implemented using the following particular embodiments of its implementation, clarifying or developing its essence.

[0034] In particular, service packets are transmitted periodically at a specified interval on each active radio channel between the vehicle router and the wireless communication nodes.

[0035] In particular, when receiving copies of service and user packets on a nodal switch, the first received copy of the same packet is selected, and subsequent copies of the same packet are deleted.

[0036] In particular, when the vehicle is moving, the radio communication of the vehicle router with at least one wireless communication node is terminated and radio communication is established with at least one subsequent wireless communication node located further along the route of the vehicle.

[0037] The specified subsequent wireless node may be associated with the same node switch as the specified wireless node with which radio communication was terminated.

[0038] The specified subsequent wireless communication node may be associated with a different nodal switch other than the nodal switch associated with the wireless communication node with which radio communication was terminated, while updating the correspondence tables in such a way that the L2 channel address of the vehicle router is excluded from the correspondence table of the specified nodal switch and added to the correspondence table of the specified other nodal switch.

[0039] When moving a vehicle, the termination of radio communication via one of the radio channels with a wireless communication node and the establishment of radio communication via the specified radio channel with a subsequent wireless communication node is carried out while maintaining radio communication via at least one other radio channel with at least one other wireless communication node.

[0040] In particular, the transmission of service and user packets between the vehicle router and wireless communication nodes, as well as the transmission of aggregated service packets and user packets between nodal switches and the data center router, are carried out over the L2 data link layer network.

[0041] The invention claims a system for transmitting data between a vehicle and a data center in a multi-channel wireless network. The claimed system comprises:

[0042] a vehicle router configured to transmit service and user packets over at least two radio channels, wherein the vehicle router has a unique L2 address, and the service packets contain at least the specified address;

[0043] at least two wireless communication nodes located along the route of the vehicle and configured to establish radio communication with the vehicle router and retransmit received service and user packets;

[0044] at least one node switch, each of which is connected to at least one wireless communication node and is configured to:

[0045] - receiving all copies of the same service or user packet received from different wireless communication nodes;

[0046] - selecting one of the received copies for further transmission;

[0047] - updates the mapping table based on the selected service packets, and the mapping table establishes a mapping between the L2 address of the vehicle router and the L2 address of this node switch;

[0048] - formation of aggregated service packets containing the L2 address of this node switch and the L2 address of the vehicle router;

[0049] a data center router connected to at least one node switch and configured to:

[0050] - receiving aggregated service packets from nodal switches;

[0051] - dynamically updating the switching table based on aggregated service packets, wherein the switching table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the nodal switch from which the aggregated service packet was last received;

[0052] - transmitting user packets from the data center router to the vehicle router through the nodal switch whose L2 address matches the L2 address of the vehicle router in the switching table of the data center router.

[0053] The claimed system for transmitting data between a vehicle and a data center in a multi-channel wireless network can be implemented using the following particular embodiments of its implementation, clarifying or developing its essence.

[0054] In particular, the vehicle router is designed as a border node that ensures interaction between the L2 data link layer domain used for communication with nodal switches and the L3 network layer domain, including at least one user device that uses L3 layer addressing to generate user packets.

[0055] In particular, the vehicle router is configured to simultaneously interact via various radio channels with wireless communication nodes associated with various nodal switches.

[0056] In particular, the vehicle router is connected to at least one radio module located in the head part of the vehicle and at least one radio module located in the tail part of the vehicle.

[0057] In particular, wireless communication nodes are placed along the vehicle's route with overlapping radio coverage areas.

[0058] In particular, at least two wireless communication nodes are combined into a segment associated with one nodal switch, wherein different network segments are formed by wireless communication nodes associated with different nodal switches.

[0059] In particular, the node switches are connected to each other via a virtual local area network (VLAN), which forms an end-to-end L2 data link layer domain.

[0060] In particular, the data center router is designed as an edge node that provides interaction between the L2 data link layer domain and the L3 network layer domain, which includes at least one server that uses L3 addressing to receive user packets.

[0061] It should be noted that the above particular features are not limited to the embodiments to which they are attributed in the claims. They may also be used in combination with other independent claims, as long as they are technically compatible with each other and are based on common design principles.

[0062] The prior art does not contain any technical solutions containing a set of essential features characterizing the claimed group of inventions, which indicates novelty.

[0063] At the same time, the prior art does not reveal any technical solutions whose features coincide with the set of distinctive features of the claimed group of inventions and at the same time ensure the achievement of a similar technical result, which confirms the presence of an inventive step.

[0064] The group of inventions can be implemented using available materials and technologies, does not require complex equipment, and is therefore industrially applicable.

[0065] All features disclosed in particular embodiments can be used in various combinations with each other, unless otherwise follows from their obvious structural or functional incompatibility.

[0066] Moreover, all technical means described for one of the variants of the invention can be implemented in a similar manner in other variants included in the claimed group, unless otherwise expressly stated.

[0067] Reducing delays and increasing the stability of user data transmission during vehicle movement is achieved through a data transmission architecture in which the vehicle router simultaneously transmits service and user packets over multiple radio channels to various wireless communication nodes, and the selection of the actual transmission path in the terrestrial network is performed at the data link layer without performing roaming and network forwarding procedures.

[0068] Transmitting user packets over multiple radio channels in parallel ensures the constant presence of at least one operational radio channel between the vehicle and the ground network while in motion. This eliminates the periods of communication loss typical of sequential channel switching and ensures uninterrupted user traffic flow to the ground network.

[0069] The generation and periodic transmission of service packets containing the vehicle router's data-link address ensures dynamic updates to the mapping tables on the node switches and the switching table on the data center router. This allows the vehicle router's data-link address (e.g., MAC address) to logically "move" between node switches as the radio access point changes, while user packets are transmitted without changing the addressing at the network layer (L3).

[0070] Since user traffic routing between the node switches and the data center router is performed at the L2 level, the need for network roaming, re-authentication, and connection state negotiation procedures typical of solutions based on controlled radio channel switching is eliminated. This significantly reduces latency associated with service exchange processing and improves data transmission stability during high-speed vehicle movement.

[0071] Furthermore, transmission resilience is enhanced by eliminating duplicate user packets arriving over different radio channels at the node switches or data center router level. This approach allows for the use of radio transmission redundancy without increasing the load on user applications or affecting their network addressing.

[0072] Taken together, the specified features ensure end-to-end logical continuity of data transmission between the vehicle and the ground network as the vehicle moves along the route, which makes it possible to ensure delay and transmission stability parameters comparable to those of a fixed connection.

[0073] Brief description of drawings

[0074] FIG. 1 shows a general diagram of a data transmission system between a vehicle and a ground network using wireless communication nodes located along the vehicle route.

[0075] FIG. 2 shows an example of a data transmission system including a vehicle router with multiple radio modules, wireless communication nodes, nodal switches, and a data center router.

[0076] FIG. 3 shows a block diagram of a method for transmitting data between a vehicle and a data processing center in a multi-channel wireless network.

[0077] FIG. 4 shows options for organizing segments of a distributed terrestrial network.

[0078] Description of embodiments of the invention

[0079] Below is a description of embodiments of the claimed group of inventions, presented as an example to better understand its essence and operating principles. The description is presented with reference to the accompanying drawings, which show various elements and embodiments of the system and data transmission method.

[0080] It should be understood that the presented embodiments do not limit the scope of legal protection for the claimed group of inventions, as defined by the claims. It is obvious to those skilled in the art that individual elements, features, and functional relationships disclosed in one embodiment may be implemented in other combinations and modifications without departing from the essence of the claimed technical solution.

[0081] The description uses the terms "comprises," "includes," and "is capable of," which do not exclude the presence of additional elements, components, or functions unless otherwise expressly stated.

[0082] The invention is based on a technology for organizing data transmission between a moving vehicle and a ground-based data transmission network, ensuring logical continuity of the network connection when the vehicle is moving in a distributed infrastructure of wireless communication nodes.

[0083] Transmitting user data between a moving vehicle and a ground network is a complex technical challenge, especially when the vehicle is moving at high speeds and maintaining a stable quality of service for user applications is necessary. Under these conditions, the vehicle successively enters the radio coverage areas of various wireless communication nodes located along its route.

[0084] As a vehicle moves along its route, its onboard network equipment sequentially interacts with various wireless communication nodes, resulting in changes in the entry points of user traffic into the ground-based data transmission network. Meanwhile, user devices located on the vehicle continue to generate and receive network traffic, requiring continuous delivery to the ground-based network, regardless of the vehicle's current position.

[0085] In traditional systems, maintaining communication under such conditions involves roaming and handover procedures, which involve establishing and terminating connections, coordinating network element states, and exchanging service messages between network participants. These procedures require a certain amount of time and involve processing protocol states, which, under high-speed conditions, leads to time intervals with increased data transmission delays and reduced network connection stability.

[0086] As a result of the above-mentioned features of traditional approaches, the quality of service for user applications that are sensitive to delays and interruptions in transmission deteriorates, and the dependence of the system's operation on the state of individual radio channels and the correctness of the switching procedures between wireless communication nodes increases.

[0087] The claimed invention aims to eliminate these limitations through a different principle for organizing network interactions between a moving vehicle and a terrestrial data network. Within this approach, user traffic transmission is organized at the network's data link layer in such a way that logical continuity of the connection is maintained regardless of changes in physical radio access points as the vehicle moves along its route.

[0088] FIG. 1 is a schematic diagram showing a data transmission system between a moving vehicle and a ground data transmission network.

[0089] A vehicle 101, such as a train, travels along a route along which wireless communication nodes 102 are located. The wireless communication nodes 102 are mounted on overhead contact line supports 103 or on other supporting structures located along the route of the vehicle 101. The placement of the wireless communication nodes 102 ensures the formation of radio coverage zones that successively cover the route of the vehicle 101 both in the direction of its travel and in the opposite direction. As a result, the vehicle 101 may simultaneously be within the radio coverage zones of several wireless communication nodes 102 while moving.

[0090] Each wireless communication node 102 is connected to at least one nodal switch 104. The nodal switches 104 form a distributed terrestrial data link layer network designed to transmit user data from the wireless communication nodes 102 to the data center router 105. The data center router 105 ensures the coupling of said distributed L2 data link layer network with the L3 network layer of the terrestrial infrastructure.

[0091] A head group of radio modules 106 is located in the head part of the vehicle 101, and a tail group of radio modules 107 is located in the tail part of the vehicle 101. Groups of radio modules 106 and 107 are connected to the on-board network of the vehicle 101 and are configured to establish wireless radio channels 108 between said on-board network and wireless communication nodes 102 located in the radio access zone of the vehicle 101.

[0092] The radio coverage areas formed by the wireless communication nodes 102 may have a different spatial configuration depending on the radio frequency ranges used, the antenna characteristics, the conditions of radio wave propagation and the features of the placement of the wireless communication nodes 102 along the route of the vehicle 101. In particular, the radio coverage areas may be formed in the form of an extended spatial region oriented along the route of the vehicle 101. In other embodiments, the radio coverage areas may have a more complex spatial shape determined by the parameters of the antennas used, as well as the conditions of radio wave propagation.

[0093] Radio channels 108 can be implemented using various radio frequency bands and wireless data transmission technologies. The radio frequency bands can be decimeter, centimeter, or millimeter wavelength ranges, including, but not limited to, V-Band, E-Band, W-Band, F-Band, and D-Band. Radio channels 108 can support full-duplex or half-duplex data transmission modes, frequency, time, or spatial channel division, and also use various modulation, coding, and transmission parameter control methods depending on radio wave propagation conditions and the speed of vehicle 101.

[0094] FIG. 2 shows a diagram of a data transmission system between a vehicle and a data processing center (DPC) in a multi-channel wireless network.

[0095] Each of the groups of radio modules 106, 107 includes at least one radio module, through which it is possible to establish a radio channel 108 with the wireless communication node 102. In the example shown, each of the groups 106, 107 includes at least two radio modules. Radio modules 201, 202 are installed in the head part of the vehicle 101, radio modules 203, 204 are installed in the tail part of the vehicle 101. Radio modules 201-204 are connected to the on-board network of the vehicle 101 via a router 205.

[0096] In accordance with FIG. 3, which shows a block diagram of a method for transmitting data between a vehicle and a data center in a multi-channel wireless network, a step 301 is performed by means of a router 205, in which service and user data packets are transmitted over at least two radio channels 108 established between the router 205 and at least two wireless communication nodes 102 located along the route of the vehicle 101.

[0097] The router 205 is designed as a border node that provides interaction between the L2 data link layer domain used to connect the vehicle 101 with the nodal switches 104 and the L3 network layer domain that includes at least one user device 206.

[0098] User devices 206 generate user packets using L3 network layer addressing and transmit said packets to router 205 via internal communication channel 207, which in various embodiments can be either wired or wireless.

[0099] The router 205 is configured to receive and aggregate user traffic coming from at least one user device 206, as well as to simultaneously interact via several radio channels 108 with various wireless communication nodes 102 via radio modules 201-204. Moreover, said wireless communication nodes 102 can be associated with either one or different nodal switches 104.

[0100] Router 205 has a unique L2 address, by which it is identified during information exchange in the L2 domain. Router 205 is configured to generate and transmit service packets containing at least its L2 address at a specified frequency.

[0101] When the vehicle 101 moves, the radio communication of the router 205 with at least one wireless communication node 102, which is outside the radio access zone of the vehicle 101, is terminated. At the same time, radio communication is established with at least one subsequent wireless communication node 102, located further along the route of the vehicle 101.

[0102] The antennas of the radio modules 201-204 of the vehicle 101 may be oriented in different directions depending on the system configuration. In one embodiment, the antennas of the radio modules 201, 202 are oriented primarily in the direction of travel of the vehicle 101, and the antennas of the radio modules 203, 204 are oriented primarily in the direction opposite to the direction of travel.

[0103] The antennas of the radio modules of the wireless communication nodes 102 may also be oriented in different directions. In particular, each wireless communication node 102 may comprise at least one radio module with an antenna oriented primarily in the direction of movement of the vehicle 101, and at least one radio module with an antenna oriented primarily in the opposite direction, which ensures the establishment and maintenance of wireless communication with the vehicle 101 both as it approaches the wireless communication node 102 and as it moves away from it.

[0104] The antennas of the radio modules of the vehicle 101 and the wireless communication nodes 102 can be made with a fixed or steerable radiation pattern and provide for the formation of radiation patterns in one or more directions, including lateral directions relative to the longitudinal axis of the vehicle 101.

[0105] At step 302, service and user packets received by wireless communication nodes 102 are relayed to nodal switches 104 associated with wireless communication nodes 102 that carry out radio communication with router 205.

[0106] Wireless communication nodes 102 are connected to at least one nodal switch 104, wherein different wireless communication nodes 102 may be connected to different nodal switches 104 or, in certain embodiments, may be temporarily not involved in transmitting user traffic. Nodal switches 104 form a distributed L2 data link network, within which user and service data packets are transmitted.

[0107] The nodal switches 104 are connected to each other and to the data center router 105 via logical connections, in particular virtual local area networks (VLANs) 210, which form an end-to-end L2 domain.

[0108] When the vehicle 101 moves, the router 205 can stop and establish radio communication with the wireless communication nodes 102, which can be connected to both the same nodal switch 104 and different nodal switches 104.

[0109] At step 303, copies of the same user packet received via different wireless communication channels are received at nodal switches 104, which are connected to wireless communication nodes 102 participating in radio communication with router 205. These switches 104 then select one of the received copies for further transmission.

[0110] In one embodiment, the nodal switch 104 selects the first received copy of a user packet and discards subsequent copies of the same packet.

[0111] In other embodiments, the selection of a copy of a user packet may be performed based on other criteria, including, but not limited to, the time of receipt of the copy of the packet or the identifier of the wireless node 102 from which the corresponding copy was received.

[0112] The selected copy of the user packet is transmitted by the nodal switch 104 towards the data center router 105 via the L2 data link layer network.

[0113] As vehicle 101 moves along the route, radio modules 201-204 sequentially enter and exit the radio coverage zones of various wireless communication nodes 102. Due to the spatial separation of radio modules 201-204 and the overlapping radio coverage zones, at least one wireless radio channel 108 between vehicle 101 and the ground network remains active at any given time. The establishment and termination of individual radio channels 108 occurs independently of one another and does not require controlled connection switching procedures. User traffic is transmitted simultaneously over all available radio channels 108.

[0114] Data center router 105 is designed as an edge node, providing interaction between the L2 data link domain and the L3 network domain. User packets are transmitted from the L2 domain to the L3 network domain via connection 210 to data center 211, which then routes user traffic to external network resources according to the recipient's L3 address.

[0115] FIG. 2 shows the boundaries of the L2 domain 212, which includes radio modules 201-204, wireless communication nodes 102 and nodal switches 104, as well as the L3 domain 213, which includes at least one user device 206 and a data processing center 211.

[0116] L3 network layer addresses (e.g., IP addresses) are used by user devices to logically identify endpoints and form end-to-end network connections. For example, a user device can generate packets with a source IP address of 10.0.1.25 and a destination IP address of 10.0.1.25, with these addresses remaining unchanged regardless of the movement of vehicle 101.

[0117] L2 data link layer addresses (e.g., MAC addresses) are used to deliver packets (frames) between directly communicating communication nodes within an L2 domain. A MAC address is an identifier of the entry point into the L2 domain and is used to select the physical path for packet transmission between radio modules 201-204, wireless communication nodes 102, and nodal switches 104.

[0118] Changing MAC addresses and physical entry points of traffic into the terrestrial network does not change IP addressing and does not require reestablishing network connections. The user IP packet maintains its identity throughout transmission, while changes to delivery paths occur exclusively at the L2 data link layer.

[0119] As an alternative to the MAC address, other physical or data link layer identifiers may be used, such as local port identifiers, VLAN identifiers, tunneling labels, or other means of identifying frames to ensure delivery of data within the L2 domain.

[0120] User packet processing using L3 network layer addressing is required exclusively on the user device 206 side and the data center side. User data transmission between the transport vehicle 101 and the node switches 104 occurs in the L2 data link layer domain, where packet processing is limited to frame switching operations, source and destination identification at the data link layer, and the removal of duplicate frames.

[0121] In systems where vehicle mobility is implemented at the L3 network layer, changing the connection point requires procedures related to route changes, addressing reconfiguration, connection state updates, or the use of additional encapsulation mechanisms. Such procedures inevitably involve overhead, computational processing, and time delays, which are particularly noticeable during high-speed vehicle movement.

[0122] In the claimed invention, changes to physical radio access points do not result in changes to network layer addressing and do not require user traffic routing procedures. All changes related to vehicle 101 mobility are processed at the data link layer, eliminating network-related delays and ensuring stable and uninterrupted user data transmission at high speeds.

[0123] To ensure the correct transmission of user packets and updating information about the binding of vehicle 101 to the elements of the ground network, the system uses service exchange carried out at the L2 level.

[0124] The service exchange includes the transmission by the router 205 of the vehicle 101 of periodic service packets containing at least a unique L2 address of the said router, on each active radio channel 108 between the router 205 and the wireless communication nodes 102.

[0125] The service packets received by the wireless communication nodes 102, as well as the user packets, are retransmitted to the corresponding nodal switches 104, each of which is configured to receive all copies of the same service packet received from different wireless communication nodes 102, and to select one of the received copies for further processing.

[0126] At step 304, the mapping table is updated on each node switch 104 based on the received service packets selected from the received copies. The mapping table establishes a mapping between the L2 address of router 205 and the L2 address of the given node switch 104 upon receipt of the selected copy of the service packet.

[0127] In one implementation example, service exchange is carried out in the form of regular distribution of heartbeat-type service packets, implemented in the form of GARP (Gratuitous ARP) frames. Router 205 of vehicle 101 periodically, for example, at intervals of approximately 5 ms, transmits GARP frames over each active radio channel 108. These frames contain the L2 link address of router 205, as well as associated network layer addressing parameters, including the IP address and network mask.

[0128] By regularly sending out the specified GARP frames and dynamically updating the mapping and switching tables at the L2 level, the channel address of the router 205 of the vehicle 101 is maintained as it moves along the route without using network layer routing protocols and without performing roaming or handover procedures.

[0129] The mapping table of the node switch 104 may contain entries of the following type: the L2 address of the router 205; the identifier of the port, VLAN, or logical interface through which the corresponding service packet was received; additional service parameters (for example, the time of the last update).

[0130] When the vehicle moves and radio communication is established between the router 205 and the subsequent wireless communication node 102, a situation may arise in which the subsequent wireless communication node 102 is connected to a different nodal switch 104 than the nodal switch 104 connected to the wireless communication node 102 with which radio communication was terminated. In such a case, the correspondence tables are updated such that the L2 address of the router 205 is excluded from the correspondence table of the said nodal switch 102 and added to the correspondence table of the said other nodal switch 102.

[0131] The L2 path selection for user packets is based on current entries in the mapping table. When the physical radio access point of router 205 changes, updating the corresponding entry in the mapping table automatically redirects user packets through the new interface.

[0132] At step 305, aggregated service packets are generated at each nodal switch 104 receiving service packets from router 205. The aggregated service packet is generated based on information contained in selected copies of the service packets, and it contains at least the L2 address of the specified nodal switch 104 and the L2 address of the router 205 associated with it.

[0133] The aggregated service packet may further contain one or more of the following service characteristics: an identifier of the wireless node 102 through which the selected copy of the service packet was received; an identifier of a port, VLAN, or logical interface of the nodal switch 104 associated with the specified wireless node; and a time of reception of the service packet.

[0134] Host switches 104 transmit aggregated service packets to data center router 105. Service packets, including aggregated service packets, are transmitted independently of user packets.

[0135] At step 306, the switching table on the data center router is dynamically updated based on the aggregated service packets.

[0136] The specified switching table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the node switch from which the aggregated service packet was last received.

[0137] Upon receiving each successive aggregated service packet, the data center router 105 updates the switching table entry in such a way that the traffic addressed to the L2 link address of the vehicle router 205 is redirected towards the nodal switch 104 that is currently associated with this L2 address.

[0138] When aggregated service packets are received from different node switches 104, the mapping in the switching table is updated dynamically based on the criterion of the last received aggregated service packet.

[0139] Using this mechanism, data center router 105 identifies router 205 of vehicle 101 as a regular, stationary L2 node, despite its physical movement along the route. The movement of vehicle 101 only changes the entry point of link traffic into the distributed network, but does not change network addressing or require rebuilding network-layer routes.

[0140] When vehicle router 205 simultaneously communicates via radio channels 108 with wireless communication nodes 102 connected to the same nodal switch 104, the processing of service and user packets occurs within a single segment of the distributed terrestrial network. In this case, all packet copies are received by said nodal switch 104, where they are deduplicated and aggregated service packets are formed. User packets are then transmitted toward data center router 105 via the L2 data link network.

[0141] When the vehicle 101 moves, a situation may arise in which the router 205 simultaneously establishes radio channels 108 with wireless communication nodes 102 belonging to different segments of the distributed terrestrial network and, accordingly, connected to different nodal switches 104. In this mode, the same service and user packets can be received and processed by several nodal switches 104, which requires coordinated operation for correct maintenance of the channel address of the router 205 and ensuring logical continuity of data transmission.

[0142] To explain the principles of segment organization of a distributed terrestrial network and interaction between segments, the example shown in FIG. 4 is further considered.

[0143] FIG. 4 shows an example of a segmented organization of a distributed terrestrial data transmission network, illustrating the operation of the system in a mode in which the vehicle 101 simultaneously interacts with wireless communication nodes 102 belonging to different network segments.

[0144] In the example shown, the distributed ground network is divided into at least two segments 401 and 402. Each segment 401, 402 includes a group of wireless communication nodes 102, sequentially located along the route of the vehicle 101, and at least one nodal switch 104, associated with the corresponding group of wireless communication nodes 102.

[0145] The nodal switches 104 of segments 401 and 402 are interconnected via a data link layer L2 network and are connected to the data center router 105, which ensures the transmission of user data towards the L3 network layer domain.

[0146] When the vehicle 101 moves along the route, a mode is possible in which various radio channels 108 of the router 205 of the vehicle 101 are simultaneously established with wireless communication nodes 102 belonging to different segments 401 and 402.

[0147] In this mode, copies of the same service and user packets transmitted by the router 205 of the vehicle 101 are received by the nodal switches 104 of different segments 401 and 402.

[0148] Each of the nodal switches 104 performs local processing of received packets, including selecting one copy of the packet and generating aggregated service packets containing information about the correspondence of the L2 address of the router of the vehicle 101 to this nodal switch 104.

[0149] By transmitting aggregated service packets from nodal switches 104 of segments 401 and 402 towards the data center router 105, the switching table on the data center router 105 is dynamically updated.

[0150] In this case, the L2 address of the vehicle router 101 is associated with the nodal switch 104 from which the aggregated service packet was received last.

[0151] At step 307, user data packets are transmitted from the router of the data center 105 to the router 205 of the vehicle 101 via the L2 data link layer network based on the switching table generated on the router of the data center 105.

[0152] According to the specified switching table, the data center router 105 selects the nodal switch 104 with which the L2 address of the router 205 is currently associated, and transmits user packets towards the selected nodal switch 104.

[0153] After receiving the user packet, the nodal switch 104 carries out further transmission of the said packet based on its own mapping table, in which the L2 address of the router 205 of the vehicle 101 is mapped to a specific port, VLAN or logical interface associated with the wireless communication node 102, which currently supports the wireless communication channel 108 with the router 205.

[0154] In this case, the mapping table of the nodal switch 104 determines the actual transmission path of the user packet from the nodal switch 104 to the router 205 via the corresponding wireless node 102 and the active radio channel 108.

[0155] As the vehicle 101 moves along the route and interacts with different wireless communication nodes 102 and, accordingly, with different nodal switches 104 at different times, the L2 address of the router 205 of the vehicle 101 is sequentially associated with different nodal switches 104 of the distributed ground network, which is reflected in the switching table of the router of the data center 105.

[0156] In one embodiment, the vehicle router 205 is currently interacting with wireless communication nodes 102 that belong to one segment 401 of a distributed terrestrial network.

[0157] In this case, the L2 address of the vehicle router 205 in the switching table of the data center router 105 is associated with the nodal switch 104 of the corresponding segment 401, as a result of which user packets are transmitted from the data center router 105 towards the specified nodal switch 104.

[0158] After receiving user packets, the nodal switch 104 transmits them based on its own correspondence table, which determines through which port, VLAN or logical interface the said packets should be sent to the wireless communication nodes 102 with which the radio channels 108 are currently established by the vehicle router 205. Then, the user packets are transmitted through the corresponding wireless communication nodes 102 via the radio channels 108 to the router 205.

[0159] In another embodiment, the router 205 simultaneously communicates with wireless nodes 102 belonging to different segments 401, 402.

[0160] In this case, user packets are transmitted from the data center router 105 through the nodal switch 104 of the segment that, in accordance with the switching table of the data center router 105, is currently associated with the L2 address of the vehicle router 205.

[0161] After receiving user packets, the nodal switch 104 of the specified segment carries out their further transmission based on its own correspondence table.

[0162] When the segment associated with the L2 address of the vehicle router 205 changes, the switching table of the data center router 105 is dynamically updated based on the aggregated service packets, and the corresponding correspondence tables of the nodal switches 104 ensure correct delivery of user packets to the current wireless communication nodes 102.

[0163] Thus, despite the movement of the vehicle 101 and the change in the ground network node through which its current connection is carried out, for the data center router 105, the vehicle 101 continues to be perceived as a logically single node of the L2 data link layer, while the change in the actual entry point to the distributed network is reflected exclusively in the update of the mapping tables on the nodal switches 104 and the switching table on the data center router 105. This ensures the transmission of response user packets towards the vehicle 101, excluding both packet loss and the need to change network addressing or perform network layer routing procedures.

Claims

1. A method for transmitting data between a vehicle and a data processing center (DPC) in a multi-channel wireless network, comprising the following steps: transmitting service and user packets over at least two radio channels between a vehicle router and at least two wireless communication nodes located along the vehicle's route, wherein the vehicle router has a unique L2 address, and the service packets contain at least the specified address; retransmission of service and user packets received by wireless communication nodes to nodal switches connected to wireless communication nodes that carry out radio communication with the vehicle router; receiving at each of the specified nodal switches all copies of the same packet received from different wireless communication nodes, and selecting one of the received copies for further transmission; updating a correspondence table at each nodal switch based on the received service packets selected from the received copies, wherein the correspondence table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the given nodal switch upon receipt of the selected copy of the service packet; generating, at each nodal switch receiving service packets from the vehicle router, aggregated service packets containing the L2 address of the said nodal switch and the L2 address of the vehicle router associated with it, and transmitting the aggregated service packets to the data center router; dynamically updating the switching table on the data center router based on aggregated service packets, wherein the switching table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the nodal switch from which the aggregated service packet was last received; and transmission of user packets from the data center router to the vehicle router via a nodal switch whose L2 address matches the L2 address of the vehicle router in the switching table on the data center router.

2. The method according to paragraph 1, characterized in that service packets are transmitted periodically at a specified interval over each active radio channel between the vehicle router and the wireless communication nodes.

3. The method according to paragraph 1, characterized in that when receiving copies of service and user packets at the nodal switch, the first received copy of the same packet is selected, and subsequent copies of the same packet are deleted.

4. The method according to paragraph 1, characterized in that when the vehicle is moving, radio communication between the vehicle router and at least one wireless communication node is terminated and radio communication is established with at least one subsequent wireless communication node located further along the vehicle’s route.

5. The method according to paragraph 4, characterized in that said subsequent wireless communication node is connected to the same nodal switch as said wireless communication node, radio communication with which was terminated.

6. The method according to paragraph 4, characterized in that said subsequent wireless communication node is connected to a different nodal switch, different from the nodal switch connected to the wireless communication node with which radio communication was terminated, while updating the correspondence tables in such a way that the L2 channel address of the vehicle router is excluded from the correspondence table of said nodal switch and is added to the correspondence table of said other nodal switch.

7. The method according to paragraph 4, characterized in that when the vehicle is moving, the termination of radio communication via one of the radio channels with the wireless communication node and the establishment of radio communication via the specified radio channel with the subsequent wireless communication node is carried out while maintaining radio communication via at least one other radio channel with at least one other wireless communication node.

8. The method according to paragraph 1, characterized in that the transmission of service and user packets between the vehicle router and the wireless communication nodes, as well as the transmission of aggregated service packets and user packets between the nodal switches and the data center router, is carried out over a L2 data link layer network.

9. A system for transmitting data between a vehicle and a data processing center (DPC) in a multi-channel wireless network, comprising: a vehicle router configured to transmit service and user packets over at least two radio channels, wherein the vehicle router has a unique L2 address, and the service packets contain at least the specified address; at least two wireless communication nodes located along the route of the vehicle and configured to establish radio communication with the vehicle router and retransmit received service and user packets; at least one nodal switch, each of which is connected to at least one wireless communication node and is configured to: – receiving all copies of the same service or user packet received from different wireless communication nodes; – selection of one of the received copies for further transmission; – updating the mapping table based on the selected service packets, whereby the mapping table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the given nodal switch; – formation of aggregated service packets containing the L2 address of the given nodal switch and the L2 address of the vehicle router; a data center router connected to at least one node switch and configured to: – receiving aggregated service packets from nodal switches; – dynamic updating of the switching table based on aggregated service packets, wherein the switching table establishes a correspondence between the L2 address of the vehicle router and the L2 address of the nodal switch from which the aggregated service packet was last received; – transmission of user packets from the data center router to the vehicle router via a nodal switch whose L2 address corresponds to the L2 address of the vehicle router in the switching table of the data center router.

10. The system according to claim 9, characterized in that the vehicle router is designed as a border node that ensures interaction between the L2 data link layer domain used for communication with nodal switches and the L3 network layer domain, which includes at least one user device using L3 layer addressing to generate user packets.

11. The system according to claim 9, characterized in that the vehicle router is designed with the ability to simultaneously interact via various radio channels with wireless communication nodes associated with various nodal switches.

12. The system according to claim 9, characterized in that the vehicle router is connected to at least one radio module located in the head of the vehicle and at least one radio module located in the tail of the vehicle.

13. The system according to claim 9, characterized in that the wireless communication nodes are located along the route of the vehicle with overlapping radio coverage areas.

14. The system according to claim 9, characterized in that at least two wireless communication nodes are combined into a segment connected to one nodal switch, wherein different network segments are formed by wireless communication nodes connected to different nodal switches.

15. The system according to claim 9, characterized in that the nodal switches are connected to each other via a virtual local area network (VLAN), which forms an end-to-end domain of the L2 data link layer.

16. The system according to claim 9, characterized in that the data center router is designed as a border node that ensures interaction between the L2 data link layer domain and the L3 network layer domain, including at least one server that uses L3 addressing to receive user packets.

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