Method and system for providing high speed communication on high speed railways

Abstract

The invention relates to the field of communications, and more particularly to a method and system for providing high speed communications on a high speed railway. The technical result is a better quality communications channel provided by a "train-to-ground" type radio relay link. The claimed system for providing high speed communications on a high speed railway includes an internal and an external data exchange network. The internal network combines a tail radio frequency module (mounted at the rear of the train and equipped with a narrow directional antenna), a head radio frequency module (mounted at the front of the train and equipped with a narrow directional antenna), and a switching device (capable of processing signals from the modules and providing access to the external data exchange network to network devices associated with the device). The external data exchange network combines base stations with narrow directional antennas, which are capable of establishing communications with the tail and head radio frequency modules in the train, and are installed along the train route near the railway gauges. The base stations and the antennas of the radio frequency modules in the train are configured to emit radio waves in the short millimeter wave range.

Description

Technical Field

[0001] This invention relates to the field of communications, specifically to methods and systems for providing high-speed communication on high-speed railways. This invention can be applied to "vehicle-to-ground" computer networks. Background Technology

[0002] The paper "High-speed and handover-free communications for high-speed trains using switched WDM fiber-wireless system" (Dat, Pham Tien, et al. 2018 Optical Fiber Communications Conference and Exposition (OFC). IEEE, 2018.) discloses a known communication system for high-speed rail transportation. The known system includes multiple remote antenna elements connected to a base station, which receive signals transmitted via an optical fiber communication path generated in a centralized transceiver node and modulated by radio frequency signals. These signals on the antenna elements are then transmitted to a millimeter frequency range and to a receiver mounted on the moving train. To switch antennas between cells (where the train terminates during its movement), a fast-tunable laser is introduced into the system to change the signal wavelength. In the described example, two lasers are used: the first laser changes the signal wavelength to switch between the first and third cells in the train path, and the second laser changes the signal wavelength to switch between the second and fourth cells. The signal routing designed for transmission to the train receiver is achieved using a seamless channel spectrum multiplexing technique.

[0003] US Patent No. 10292058B2 (published May 14, 2019, titled "Radio over fiber antenna extender systems and methods for high-speed trains") discloses a system for providing broadband internet access in railway transportation. The known system includes multiple antennas installed outside the train carriages, multiple wireless access points installed inside the train carriages, and a control system. The antennas are capable of exchanging data with a cellular communication network. The antennas and access points are interconnected and connected to a control unit via an optical fiber communication path. The control system is capable of establishing a communication channel with a base station, collecting data on train speed and the signal reception and transmission times between the train antennas and the base station. Based on this data, the control system can adapt a data processing program.

[0004] US Patent Application No. 20160249233A1 (publication date: August 25, 2016, title: "Providing broadband service to trains") discloses a method for providing connectivity to a network gateway installed in a vehicle. Known methods assume that the network gateway is configured to provide cellular radio communications to mobile devices of users within the vehicle. To this end, the method provides cellular coverage along the vehicle's route. In this case, each network cell is designed to communicate with the gateway, and all cell sets are configured to provide communication between the vehicle gateway and the core cellular radio network.

[0005] However, although the known invention provides the execution of program instructions designed to compensate for communication loss between the user and the base station due to the high speed of the train, errors may occur in the data transmission from the base station to the train.

[0006] Furthermore, calculating a model to compensate for noise in transmitted data requires train timetables, train speeds throughout the journey, and consideration of weather conditions. Such a model is extremely difficult to implement and hard to apply to computer networks providing internet access to passenger train users.

[0007] Furthermore, the availability of base stations is generally necessary to provide connectivity, which is not always possible along passenger train routes and is therefore unprofitable due to the lack of frequent users on these routes. As is known, trains mostly travel through uninhabited or sparsely populated areas.

[0008] Finally, using LTE, it is currently impossible to provide data transmission rates up to 10Gbps because the implementation of this technology lacks the necessary frequency bands in which data exchange at such rates is possible. A channel with this capacity between the base station and the mobile train is possible as long as data is exchanged within the millimeter-scale radio frequency range. However, to guarantee data transmission rates up to 10Gbps, it is necessary to adhere to the condition of providing direct visibility between the base station and the mobile train. This is a practical technical problem because there are numerous natural obstacles to propagation waves in the areas where trains travel.

[0009] For the use of Wi-Fi-based technology, these technologies currently have significant limitations in providing internet access on high-speed trains. Wi-Fi signals are very sensitive to Doppler shift. In practice, this means that data rates decrease as train speed increases. Furthermore, Wi-Fi signals weaken rapidly as the train moves from one access point to another. Providing broadband connectivity on high-speed trains using inexpensive Wi-Fi technology becomes extremely expensive because it requires short distances between base stations along the train line.

[0010] PCT international patent application (publication date: July 26, 2012, priority filed on January 18, 2011, under CN2011100205309A, English title: "High-speed railway microwave communication network") discloses a high-speed railway wireless relay communication system. Known systems include multiple radio relay transceivers placed along the railway track, and radio relay transceivers mounted on moving vehicles, with the transceivers forming a coverage area. At least one transceiver mounted on the vehicle relays radio signals between equipment mounted along the railway track (including within the coverage area in the vehicle direction) and the vehicle's internal network. The frequency range of the radio signals corresponds to the 4 GHz to 42 GHz range. Summary of the Invention

[0011] The technical problem of this invention is to provide a broadband connection between a moving train and ground equipment at an information transmission rate of 2-10Gbps via a "vehicle-to-ground" type wireless relay communication line, so as to facilitate data exchange using the OSI / ISO network model.

[0012] The technical result achieved in this invention is to improve the quality of the communication channel provided by vehicle-to-ground wireless relay communication lines.

[0013] The first aspect of the invention discloses a method for providing high-speed communication on a high-speed railway, wherein a base station connected to an external data transmission network is installed along the train route; the base station is equipped with a highly directional antenna capable of communicating with head and tail radio frequency modules installed on the train, and also equipped with a narrow-directional antenna and integrated into an internal data transmission network; the position of the base station relative to the railway clearance provides direct visibility between the base station antenna and the radio relay module antenna installed on the train, and the method includes the following steps:

[0014] - Transmit radio waves in the short millimeter wave range on the antennas of the base station and radio frequency module of the mobile train;

[0015] - Establish communication channels between the first head module and the nearest base station in front of it, and between the first tail module and the base station closest to it behind it;

[0016] - Before passing the base station located ahead, establish a communication channel between the second head module and the next base station closest to the train;

[0017] - After the train passes the base station located in front of the train, a communication channel is established between the second tail module and the base station.

[0018] Furthermore, radio signals exchanged through established communication channels are processed on switching equipment associated with the radio frequency module, providing network equipment on the train with access to external data exchange networks.

[0019] Additional advantages and essential features of the present invention may be presented in the following specific embodiments.

[0020] Specifically, the antennas of the first and second head modules face the base station located in front of the moving train, and the antennas of the first and second tail modules face the base station located behind the train.

[0021] Specifically, the radio relay antenna of the base station is configured to transmit a beamwidth of narrow.

[0022] Specifically, the communication channel between the railway train base station transceiver and the wireless relay module transceiver is set to full-duplex mode, and the channel is divided by frequency and polarization.

[0023] Specifically, the transmitted radio waves are located in one of the radio frequency bands selected from the V-band, E-band, W-band, F-band, and D-band groups.

[0024] A second aspect of the invention discloses a method for providing high-speed communication on a high-speed railway, wherein a base station connected to an external data transmission network is installed along the train's route; the base station is equipped with a highly directional antenna capable of communicating with head and tail radio frequency modules installed on the train, and also equipped with a narrow-directional antenna and integrated into an internal data transmission network; the location of the base station relative to the railway clearance provides direct visibility between the base station antenna and the radio relay module antenna installed on the train; and the method includes the following steps:

[0025] - Transmit radio waves in the short millimeter wave range on the antennas of the base station and radio frequency module of the mobile train;

[0026] - Establish a communication channel between the first head module, the first tail module and the base station closest to them located behind them, and at the same time establish a communication channel between the second head module and the nearest module located in front of the base station.

[0027] - Before passing the base station located ahead, a communication channel is established between the second tail module and the base station;

[0028] Furthermore, radio signals exchanged through established communication channels are processed on switching equipment associated with the radio frequency module, providing network equipment on the train with access to external data exchange networks.

[0029] The second invention solves the technical problem that the first invention also solved. A particular embodiment of the second invention assumes that the antennas of the first head and first tail modules face a base station located behind the moving train, and the antennas of the second head and second tail modules face a base station located in front of the train.

[0030] A third aspect of the invention discloses a system for providing high-speed communication on high-speed railways, the system comprising internal and external data exchange networks, and simultaneously:

[0031] - The internal network consists of a tail radio frequency module (equipped with a narrow directional antenna) installed at the rear of the train, a head radio frequency module (equipped with a narrow directional antenna) installed at the front of the train, and switching equipment (capable of processing signals from the modules and providing access to external data exchange networks to network devices associated with the equipment).

[0032] - An external data exchange network combines a base station with a narrow-direction antenna, and the base station is able to establish communication with the rear and front radio frequency modules of the train and is installed along the train route so that the location of the base station relative to the railway clearance provides direct visibility between the base station antenna and the radio relay module antenna installed on the train;

[0033] In addition, the antennas of the base station and the radio frequency module installed on the train are configured to transmit radio waves in the short millimeter wave range.

[0034] Additional advantages and essential features of the present invention may be presented in the following specific embodiments.

[0035] Specifically, the antennas of the first and second head modules can be directed toward a base station located in front of the moving train, and the antennas of the first and second tail modules can be directed toward a base station located behind the train.

[0036] Specifically, the antennas of the first head module and the first tail module can be directed toward the base station located in front of the moving train, and the antennas of the second head module and the second tail module can be directed toward the base station located behind the train.

[0037] Specifically, the base station is located on the railway overhead contact line support.

[0038] Specifically, the base station is located on a support between the railway clearance boundary and the railway catenary support closest to that boundary.

[0039] Specifically, the base station is connected to the network via fiber optic communication.

[0040] Specifically, each base station and each radio frequency module installed on the train consists of several devices that provide switching, routing, receiving, and transmitting of wireless signals.

[0041] Analysis of patents and scientific and technological literature shows that the prior art does not know all the features of the present invention. Therefore, there is reason to believe that the present invention meets the "novelty" condition for patentability.

[0042] Furthermore, no patents or other sources of information were found to disclose the impact of the invention’s distinguishing features on the technical results it provides; that is, it is not obvious to an expert. Therefore, there is reason to believe that the invention meets the “inventive step” requirement for patentability.

[0043] Based on well-known and promising technologies and objective physical laws, this invention can be put into practice, which shows that the invention meets the "applicability" condition for patentability.

[0044] In this specification, the term "radio frequency module" primarily refers to equipment installed on the train. It should be understood that nodes such as radio frequency modules are also used in the construction of base stations. To eliminate potential discrepancies, the specification provides a separate direct indication that the radio frequency module specifically refers to a base station. Where no indication is given, the radio frequency module should be considered part of the train data network equipment. The term "radio frequency module" does not represent a complete, standalone communication device, but rather a collection of transceivers, routers, and switching nodes, functionally combined as part of a single radio frequency module.

[0045] Additionally, the text will further indicate that the radio frequency module includes a radio frequency transceiver. In this context, it should be understood that the term "radio frequency transceiver," which indicates its ability to operate at radio wave frequencies, refers to the component of the rear or front radio frequency module installed on the train, i.e., the base station installed on the overhead contact line support.

[0046] The term "railway clearance" refers to the lateral limits perpendicular to the profile axis of the railway track, excluding parts with no structure or device other than railway locomotives and rolling stock, as well as materials, spare parts, and equipment located near the railway track, and device parts that directly interact with railway locomotives and rolling stock (contact lines with fasteners, hydraulic columns for water collection, etc.); provided that these devices are located in the internal space connected to the corresponding components of the railway locomotives and rolling stock, and that they do not cause contact with other components of the railway locomotives and rolling stock (International Standard GOST 9238-2013 Railway Locomotive and Rolling Stock Clearance and Building Proximity Clearance).

[0047] The term "V-band" refers to the range of radio waves with frequencies from 40 to 75 GHz.

[0048] The term "E-band" refers to the range of radio waves with frequencies of 71–76 GHz and 81–86 GHz.

[0049] The term "W-band" refers to the range of radio waves with frequencies from 75 to 110 GHz.

[0050] The term "F-band" refers to the range of radio waves with frequencies from 90 to 140 GHz.

[0051] The term "D-band" refers to the range of radio waves with frequencies from 110 to 170 GHz.

[0052] The term "IQ signal" refers to a digital or analog signal presented in the form of in-phase (I) and quadrature (Q) components.

[0053] The term "PLL" refers to phase automatic frequency fine-tuning.

[0054] The term "PoE" refers to the standardized Power over Ethernet technology, which allows a device to transmit power and data to another device via a standard twisted-pair cable over an Ethernet network.

[0055] The term "OSI network model" refers to the standardized network model of the OSI / ISO network protocol stack. This model allows various network devices to interact with each other. The model defines different layers of system interaction. Each layer (represented by the prefix L and the numbers in the model) performs certain functions in this interaction.

[0056] The terms "head" and "tail" used for radio frequency modules conditionally reflect their spatial location on the train, and the use of these terms depends solely on the direction of train movement. When the train moves in the opposite direction, the term "head module" can refer to a module that was previously located at the tail of the train, and vice versa, without changing the technical nature of the node.

[0057] Further explanations of the invention, its features, and the technical problems it solves are disclosed in more detail in the detailed description of embodiments of its implementation, with reference to the accompanying drawings. Attached Figure Description

[0058] Figure 1a and Figure 1b Obstacles in the vehicle-to-ground communication channel are shown.

[0059] Figure 1c A schematic diagram of the organization of the vehicle-to-ground communication channel is shown;

[0060] Figure 2 and Figure 3 The functional flowcharts of the RF head module, RF tail module, and base station RF transceiver and routing module are shown.

[0061] Figure 4a and Figure 4b A flowchart illustrating a method for providing high-speed communication on high-speed railways is shown;

[0062] Figure 5a The image shows the placement of the base station on the overhead contact line support.

[0063] Figure 5b , Figure 5c , Figure 5d A graph showing the calculation of the first Fresnel zone as radio waves propagate along a railway track is displayed;

[0064] Figure 6 The diagram shows the received signal strength of the receiver installed on the train. Detailed Implementation

[0065] The description of the embodiments of the present invention can serve as an example for a better understanding of its nature, and is illustrated with reference to the accompanying drawings. However, the following details are not intended to limit the scope of the invention, but only to make it clearer.

[0066] This invention is based on a technology that provides wireless relay communication, allowing for long-distance data transmission while increasing the capacity of established communication channels. To improve data transmission capacity, this invention introduces a base station located on the train track close to the railway clearance. According to railway regulations, space within the railway clearance is always free. This base station arrangement allows for direct visibility between its antenna and the antenna of the radio relay module mounted on the train.

[0067] Since the required information transmission rate of around 10 Gbps necessitates the availability of a free band on the order of several GHz, technically, this can only be achieved in the millimeter-wave range. Simultaneously, due to the nature of wave propagation in the millimeter-wave range, maintaining direct visibility is essential. Furthermore, the requirement to provide a free zone within the first Fresnel zone during radio wave propagation is crucial. The first Fresnel zone in space occupies the volume of a rotating ellipse, where all useful transmission information is concentrated. Figure 1a The illustration shows a base station 102 mounted on a single mast along the route of train 101. When the wave propagates into the volume corresponding to the first Fresnel zone, obstacles 103 of a natural (landscape, forest vegetation) or man-made (buildings, railway infrastructure, bridges, tunnels) nature will inevitably appear. In this case, even without a significant obstacle 103 in the wave propagation path, the line of sight of the base station 102, located beyond the distance of the support pillar 104 of the high-voltage power infrastructure along the railway track, will be limited by the support pillar 104 of that infrastructure itself. Figure 1b The effect of blocking the line of sight from standalone base station 102 to moving train 101 is shown. The greater the distance the train 101 travels from base station 102, the smaller the viewing angle from base station 102 to the railway track. In this case, a row of pillars 104 of the high-voltage infrastructure visually merges into a solid barrier in the perspective view.

[0068] Base station 102 employs an antenna capable of transmitting radio waves within a millimeter range. As is known, millimeter waves fall within the radio wave range of 10 mm to 1 mm wavelength, corresponding to frequencies from 30 GHz to 300 GHz. Compared to lower frequency bands, millimeter-wave radio waves have shorter wavelengths. This allows for improved radio communication range and quality over long distances when operating within corridors formed by pillars 104 of infrastructure suspended by high-voltage power lines, as the volume occupied by the first Fresnel zone becomes more compact with decreasing wavelength. Eliminating contact between radio waves and obstacles 103 present in their propagation path significantly reduces the probability of lost signal payload. In this sense, the shortest possible wavelength is appropriate. However, the fact that weather conditions can be an obstacle to the propagation of short radio waves should be considered. As is known, millimeter-wave radio waves penetrate fog well, therefore shorter radio waves (such as visible light) that attenuate effectively in fog are impractical. In this respect, the ideal approach is to use the operating frequency ranges of V-band, E-band, W-band, F-band, and D-band. On the one hand, commercial solutions have already been developed, and on the other hand, waves within these ranges can pass through fog without obstruction.

[0069] Furthermore, the antennas used in base station 102 have narrow beam patterns. All antennas are either oriented in the direction of movement of train 101 or in the opposite direction: at its head or tail. This invention does not use antennas capable of radiating radio waves in directions outside the train path (as is typically the case with LTE or WiFi technologies). The narrow radiation pattern of the antennas used provides significant radiation concentration in a given direction. Due to the narrow beamwidth focused in that direction, long distances can be achieved, at which radio communication can be efficiently established. The narrow beamwidth allows for more precise radiation of radio signals in the direction of train 101. A radiation pattern is a graphical representation of the relative field strength transmitted or received by the antenna. Furthermore, the location of the base station near the railway clearance ensures that the narrow beam propagation will not contact or interfere with railway infrastructure.

[0070] Another significant difference in this invention is the use of radio frequency modules located at the rear and front of the train. This is necessary to ensure the quality of network connectivity between user equipment and external data networks. Therefore, there is a possibility that the communication channel between the head module and the base station may be interrupted, or that the communication channel between the tail module and the base station may be interrupted. However, the simultaneous interruption of two communication channels involving different radio frequency modules is extremely unlikely, if not almost impossible.

[0071] A distance of 2km between base stations is recommended, at which a permanent communication channel with a nominal speed of 10Gbps is more likely to be provided. However, as mentioned earlier, this is a more efficient alternative than establishing a communication channel between a moving train and a base station supporting LTE or Wi-Fi technologies. For example, in the case of using Wi-Fi, the distance between base stations would be tens of meters to provide a reliable communication channel. The cost of a wireless relay device exceeds that of a Wi-Fi access point, but at the same time, the use of wireless relay technology becomes more cost-effective, requires less maintenance, and is more reliable over longer distances. It is worth noting that the cost of installing equipment along railways is quite high in all cases. Meanwhile, technologies that allow the use of a smaller number of devices (especially base stations) to solve the problem of providing high-speed communication become more cost-effective.

[0072] It is worth noting that the proposed method and system do not require the construction of complex and large-scale infrastructure. A characteristic of railway track design is the installation of overhead contact line supports along long sections, which bear the load of cables extending along the railway and are equipped with special switching devices. The claimed invention uses this feature and relates to placing radio relay base stations on these overhead contact line supports.

[0073] This invention enables data transmission over a wide range at speeds up to 10Gbps (but not limited to) on straight, high-speed railway sections. This represents a promising direction for the development of railway communications in Russia and is being actively implemented in Europe, Japan, China, and many other countries around the world. It is noteworthy that trains operating on such railways can reach speeds of 300–400 km / h, making communication with trains using LTE and WiFi technologies more challenging.

[0074] according to Figure 1c Train 101 is traveling on a high-speed section of the railway. Contact wire supports 104 are placed along the route of train 101. Radio relay base stations 102 can be installed on each or some of the supports 104. The distance between base stations 102 is selected based on the terrain, typical weather conditions of the area, and the presence of natural barriers. For example, base stations 102 can be placed every 1 km, 2 km, or 3 km, but are not limited to these approximate distances. Preferably, the distance between base stations is selected in such a way that a line-of-sight condition is met when establishing communication between them and the radio frequency module of train 101, i.e., obstacles of various types cannot appear within the first Fresnel zone. The base stations 102 are approximately the same distance from each other, or different distances are selected from the exemplary distance group described above.

[0075] Each base station 102 includes one or more radio modules. A radio module consists of a radio frequency transceiver with a narrow-beam antenna and possibly a routing module. If base station 102 includes multiple radio modules, these modules can be included in a computer network and served by a common routing module, which can be an integral part or an external part of such radio modules, including part of another radio module that is part of the same base station. Base station 102 uses switches 105 connected via fiber optic communication paths to provide network connectivity to the backbone infrastructure of telecommunications operator 106. Preferably, the switches are selected to support the maximum data rate supported by the radio. In certain cases, each switch's network interface (port) supports a nominal data exchange bandwidth of 10 Gbps, or the switch supports increasing its bandwidth by a factor of the load from the transceivers of the radio modules. The connections of all nodes 102, 105, and 106 form an external data network.

[0076] At least two head radio frequency modules 107 are mounted at the head of train 101, and at least two tail radio frequency modules 108 are mounted at the rear of train 101. Modules 107 and 108 are connected to the internal data transmission network of train 101. This network also includes network switching equipment installed in the carriages of train 101, capable of processing, converting, and exchanging data with modules 107 and 108. The equipment provides wireless or wired access points for connecting user equipment or service network equipment, such as surveillance cameras, to passengers of train 101. When traveling along the route, train 101 is always positioned between two base stations 102 directly in front of and behind train 101. In one embodiment, head module 107 establishes a communication channel 109 with its nearest forward base station 102, and tail module 108 establishes a communication channel 109 with its nearest rear base station 102. However, some embodiments may be implemented in which radio frequency modules 107 and 108 are configured to connect simultaneously or alternately to base stations 102 located in front of and behind train 101.

[0077] Vehicle-to-ground aggregation communication channels can solve the following business and service network traffic transmission problems:

[0078] – Provides high-speed internet connectivity;

[0079] – Provides access to audiovisual media content stored in a remote network, including information on attractions along Train 101;

[0080] –Provide passengers with the opportunity to upload video and graphic materials created on the road to social networks.

[0081] In addition, the vehicle-to-ground communication channel allows the following advantages of the transmission service network traffic:

[0082] – Provides remote centralized video monitoring of the vehicle interior and detects events (such as fires);

[0083] – Provides real-time transmission of train control system parameters to the railway central control system, and provides feedback, such as responding to events by invoking the remote emergency braking function.

[0084] according to Figure 2 The tail and head radio frequency modules and base station include a radio frequency transceiver 200. The radio frequency transceiver 200 includes a transmission path implemented on the transmitter chip, with an IQ signal corrector 201 and an IQ signal to millimeter-range converter 202 soldered onto this transmission path. A receive path is connected to a duplexer 203. The duplexer 203 is connected to a receive path implemented on the receiver chip, with a millimeter-range IQ signal converter 204 and an IQ signal amplifier 205 soldered onto this receive path. The duplexer 203 interconnects the transmission and receive paths.

[0085] One of the inputs of amplifier 202 is connected to the output of frequency synthesizer 206 via a PLL that transmits the local oscillator signal through the transmission path. One of the inputs of converter 204 is connected to the output of frequency synthesizer 207 via a PLL that receives the local oscillator signal through the receiving path. The inputs of frequency synthesizers 206 and 207 are connected to the output of frequency synthesizer 208, which is associated with reference crystal oscillator 209.

[0086] Frequency synthesizers 206 and 207 can tune their operating frequencies according to commands from control unit 210. Power filtering unit 211 provides filtered power to transceiver unit.

[0087] The transceiver chip is preferably an Analog Devices surface mount chip with waveguide inputs and outputs, without the need for a waveguide slat adapter.

[0088] The digital input of the radio frequency transceiver 200 receives the in-phase and quadrature components of the information radio signal. In the corrector 201, the parameters of the signal components are aligned to compensate for inconsistencies in their paths. The signal enters the transmission path, where the information signal is transmitted to the E-band RF range at converter 202. A duplexer 203 connects the transmission and reception paths to the antenna input / output while electrically decoupling them from each other. In the reception path, the E-band RF signal is converted into the in-phase and quadrature components of the information signal at converter 204. Amplifier 205 increases the level of the signal components for subsequent transmission to the modem.

[0089] Independent tuning of each I / I' / Q / Q' channel allows for the generation of a high-quality output spectrum without leakage of the local oscillator to the transmitter output. Radio repeater bridges can be used over extremely long and short distances by digitally adjusting the transmitter output power and receiver gain coefficients.

[0090] The transceiver 200's frequency control allows operation across the entire allocated frequency bands of 71GHz–76GHz and 81GHz–86GHz. Its high level of integration allows it to be housed as a complete device in a small package, equipped with IQ data, power, and SPI control interfaces, all housed in a single connector. The bandwidth of the transmitted signal is adjustable from 64.5MHz to 2GHz. The low phase noise of the local oscillator allows the use of the following modulation types: BPSK, QPSK, 16QAM, 32QAM, 64QAM, 128QAM, and 256QAM. The output power is at least 22dBm. The receiver noise figure does not exceed 5dB. When used in conjunction with a 10GbE baseband modem, the transceiver 200 provides a point-to-point wireless relay link with an information transmission rate of up to 10Gbps.

[0091] according to Figure 3 The tail and head radio frequency modules and base station may include a routing module 300. The routing module 300 includes a serially connected modem unit 301, a host controller 302, and a switch unit 303. The switch unit is connected to a data interface (10GbE SFP+ optical interface 304) and a 1GbE PHY node 305. Each node 305 is connected to a node of a copper interface 306. The switch unit 303 is also connected to DDR3 memory 307 and NAND flash memory 312. The modem unit 301 and the switch unit 303 are also connected to a PLL digital node 309. The routing module is powered by a power supply unit 310. The power supply unit 310 supports PoE and is connected to a PoE node 311. Although... Figure 3 While there is no explicit indication of the connection between the power supply unit 310 and other units and nodes of the device, it should be understood that, apart from the PoE node 311, the power supply unit provides power to all units and nodes that require it. In various embodiments, the power supply unit 310 may power other devices and nodes that are not part of the routing module. Meanwhile, the power supply unit 310, modem unit 301, and switch unit 303 are mounted on a common board. This ensures the compactness of the device and the possibility of implementation in a single hermetically sealed housing.

[0092] The modem unit 301 is based on the SoCMaxLinear digital signal processor, which allows for a comprehensive list of digital processing functions to ensure signal exchange with the RF transceiver. Since the radio repeater module using the routing module is intended for outdoor use (e.g., on a building rooftop), choosing such a versatile processor is reasonable to reduce maintenance requirements and component replacement cycles.

[0093] In order to enable the use of the routing module in a radio relay link, the program instructions of modem unit 301 can implement one or more of the following options:

[0094] - An algorithm to compensate for transmission path predistortion nonlinearity allows for high output power of the transceiver under high modulation (128-QAM);

[0095] - Error correction algorithms in FEC signals improve receiver sensitivity index at certain BER levels;

[0096] - Adaptive modulation and ACMB band algorithms allow for automatic adjustment of radio operating modes based on weather conditions, thereby improving the availability of radio relay links.

[0097] The host controller 2 has software instructions for managing the software installed in the modem and switch units, providing a microclimate within the module housing, recording module software activity, and providing a graphical management interface.

[0098] Switch unit 303 is implemented on a network processor with an internal bus capable of processing data at speeds up to 120 Gbps. An example of such a processor is the Marvell carrier-level processor. Without this data processing capability, using a routing module would be difficult or nearly impossible when used for radio relay links. Switch unit 303 has software instructions supporting protocols above Layer 2 of the OSI network model. In some embodiments, the modem unit is capable of supporting the implementation of Layer 2+ protocols of the OSI model, i.e., Layer 2 and above functionality: supporting the switching and routing of packets for Virtual Local Area Networks (VLANs) and Quality of Service (QoS). In other embodiments, the processor is capable of executing software instructions to support Layer 3-L4 protocols. This makes the module scalable and flexibly configurable.

[0099] The head-end, tail-end RF modules, and base station are manufactured within a single hermetically sealed housing of the radio repeater module, which contains the RF transceiver 200 and the routing module 300. Both devices may be manufactured on the same board. In addition to the aforementioned devices, the RF module may include additional group nodes required for its operation. The ability to operate via PoE eliminates the need for power cables to be connected to the module. The structural components can be powered via Ethernet cables (twisted pairs). This simplifies and reduces the cost of installation and configuration of the structure.

[0100] according to Figure 4a The method for providing high-speed communication on high-speed railways is as follows.

[0101] In step 401, radio waves in the short millimeter-wave range are transmitted on the antenna of base station 104 and on the radio frequency modules 107 and 108 of the moving train 101. The radio relay antenna of base station 102 is configured to radiate narrow-beamwidth waves. Simultaneously, the antenna is characterized by a narrow radiation pattern. Although step 401 is listed first in the sequence of actions of this method, it should be understood that the radio wave radiation from the antennas of the equipment of train 101 and base station 102 is continuous, regardless of whether train 101 is within the coverage area provided by base station 102, and is substantially simultaneous with the remaining actions of the method. Radio wave radiation from the antennas of modules 107 and 108 can be performed to search for the nearest base station 102 and exchange radio signals with the payload.

[0102] In step 402, at least one communication channel is established between the head module 107 and its nearest preceding base station 102, and at least one communication channel is established between the tail module 108 and its nearest following base station 102. The number of communication channels established depends on the number of tail and head radio frequency modules 107, 108 and radio modules in base station 102. Multiple communication channels can be installed, particularly for redundancy, so that network traffic can be transmitted to a backup channel or the data transmission rate can be doubled in the event that one communication channel is interrupted. The communication channels between base station 102 and modules 107, 108 operate in full-duplex mode, with frequency division channels using the frequency division duplex (FDD) method.

[0103] To ensure continuity of connection when passing through each subsequent base station, a seamless roaming method is used, which is continuously implemented in steps 403 and 404 of this invention.

[0104] In step 403, shortly before the train passes base station 102, at least one communication channel 109 is established between head module 107 and the next nearest base station 102.

[0105] In step 404, after the train (i.e., its rear) passes the preceding base station, at least one communication channel 109 is established between the rear module 108 and the base station 102. In one embodiment, the antenna of each head module is oriented forward in substantially the same direction as the train's movement, and the antenna of each rear module is oriented backward. In this embodiment, when switching communication channels 109, one of the head modules 107 (backup) begins operating with the next nearest base station 102, and one of the head modules 107 (primary) continues operating with the nearest base station until the front of the train 101 passes it. Similarly, communication channels can be switched between the rear modules 108 and the base station 102. Thus, one of the rear modules 108 (backup) begins operating with the base station 102 after passing the preceding station, and one of the rear modules 108 (primary) continues operating with the previous base station 102.

[0106] The frequency planning is designed so that adjacent distance segments between base stations 102 have different frequencies and / or polarizations: even-numbered segments have one frequency plan and / or polarization, and odd-numbered segments have another. The backup and primary radio modules (head 107 and tail 108) are also divided by frequency and polarization. This ensures that the primary and backup modules operate simultaneously without interfering with each other in the vicinity of base station 102, albeit briefly. Head module 107 and tail module 108 operate alternately, in one frequency plan and polarization, in an even-numbered distance segment, and then in another, in an odd-numbered distance segment. The backup and primary modules 107 and 108 can only operate simultaneously shortly before the train approaches base station 102. Traffic routing for switching from one base station to the next occurs essentially instantaneously, as a communication channel with the next base station has been established and is ready to transmit traffic before the train has passed the current base station 102.

[0107] Consider an example of handover between base station 102 and modules 107 and 108. On a certain section of railway, train 101 is located between the first and second base stations 102, close to the train. Since the head and tail of train 101 do not pass the second base station simultaneously, but with some delay, communication will be provided through the communication channel between the tail module 108 and the first base station 104 during the short period of handover from the head module 107 to the third base station 102. Then, once communication has been established between the head module 107 and the third base station 102, the moment for the tail module 108 to handover to the second base station 102 will arrive. Therefore, during the main time the train travels between the base stations, both channels are involved, and traffic is aggregated. Only during the short and non-simultaneous handover time of the head module 107 or the tail module 108 is one communication channel involved, i.e., the tail or the head.

[0108] Repeat steps 403 and 404 until the last base station 102 that can be connected to by the train 101 along the route of the train 101 via modules 107 and 108.

[0109] according to Figure 4b In another embodiment, the antennas of the first head module 107 and the first tail module 108 are rearward, substantially in the same direction of train movement. The antennas of the paired second radio modules 107 and 108 are oriented forward. In step 405, after step 401, a communication channel is established between the first head module and the base station located behind the train 101 and the first tail module 108, and the same base station 102. Simultaneously, a communication channel is established between the second head module 107 and the nearest base station 102 located in front of the train 101. Before the first handover, the first modules 107 and 108 are connected to the same base station 102 located behind the train 101, and the second head module 107 is connected to the base station located in front. When approaching the base station 102, the second head module 107 sends a signal to the second tail module 108 and requests a connection to the same base station 102 shortly before the second tail module 108 passes the head of the train. As train 101 passes the preceding base station, the first head module 107, with its antenna pointing backward, establishes a communication channel with it; the first tail module 108, whose antenna is also pointing backward, continues to work with the preceding base station until a communication channel can be established with the next base station 102, which will occur after the rear of train 101 has passed. The second tail module 108, after the rear of the train has passed the base station 104 with which it has a communication channel, continues to wait for a request to connect to the next base station 102. In this embodiment, the distance between the first and second modules 107, 108 and the base station is less than the distance in the above embodiments.

[0110] Before the second switch, the first head module 107 and the first tail module 108 with their antennas pointing backward repeat step 405 and operate together with the base station 102 located behind the train; the second head module 107 with its antenna pointing forward repeats step 406 and operates together with its nearest base station 102. Shortly before the second tail module 108 passes the head of the train, the second tail module 108 with its antenna also pointing forward repeats step 407 and connects to the base station with which the second head module 107 has already operated.

[0111] Before each subsequent switch, modules 107 and 108 repeat steps 405, 406, and 407 until train 101 passes the last base station 102, at least one of the modules can be connected to the base station along the path of train 101.

[0112] In step 408, the signals from modules 107 and 108 are processed on the switching equipment of the internal data network of train 101, and access to the external data network is provided to the user equipment. It should be noted that step 408 is not the next step after step 404, but is executed in parallel with steps 402, 403, and 404 according to the flowchart shown in Figure 4a. Figure 4b In the flowchart shown, step 408 is also executed in parallel with steps 405, 406, and 407.

[0113] Figure 5a The location of base station 102 is shown. Base station 102 is installed on a support 104 of high-voltage infrastructure, at a certain distance from the railway clearance center axis 501. The case where the distance between base station 102 and axis 501 varies is considered.

[0114] Figure 5b , Figure 5c , Figure 5d The diagram illustrates a graphical representation of the first Fresnel zone during radio wave propagation along a railway track. The distance between the radio transmitter and receiver is marked on the horizontal axis, and the distance between the center of the railway track and the overhead contact line support is marked on the vertical axis. The central axis 501 of the railway track is located on the vertical axis 0. A line 502 passing through the -3.3m value indicates the position of the overhead contact line support relative to axis 501. The beam direction from the receiver (a point on the right vertical boundary of the diagram) to the transceiver (a point on the left vertical boundary of the diagram) corresponds to line 502. The first Fresnel zone is an ellipse bounded by line 504 on the diagram. Optimal signal stability and transmission quality are achieved when there are no obstructions within the first Fresnel zone; that is, the boundary 504 of this zone should not touch or cross line 502, which passes through the -3.3m value of the overhead contact line support.

[0115] Figure 5b The calculation for the first Fresnel zone is shown, where the base station antenna is positioned as close as possible to the railway clearance, 5011.8m from the central axis. This ensures maximum communication range without interfering with high-voltage infrastructure supports. As can be seen from the graph, the range is approximately 4.5km, which is the line-of-sight distance between the receiver and transceiver.

[0116] Figure 5c The calculation for the first Fresnel zone is shown, where the base station antenna is placed at a distance of 5012.6m from the central axis. Meanwhile, the distance between the receiver and transceiver (at which point the first Fresnel zone is as close as possible to the infrastructure support) corresponds to 2km.

[0117] Figure 5dThe calculation for the first Fresnel zone is shown, where the base station antenna is as close as possible to the infrastructure support, at a distance of 5013.0m from the central axis. The maximum free distance for the first Fresnel zone is approximately 500m.

[0118] When selecting the distance between base stations along the train line, the calculated Fresnel zone values ​​mentioned above can be used.

[0119] Figure 6 The graph shows the received signal strength of the train's radio frequency module. The vertical axis corresponds to the received signal level (dBm), and the horizontal axis corresponds to the distance between base stations (km). Line 601 on the graph reflects the signal strength between the rear module 108 and the base station behind the train 101. Line 602 on the graph reflects the signal strength between the front module 107 and the base station in front of the train 101.

[0120] As train 101 moves past base station 102, line 601 indicates a gradual decrease in signal strength. As the train approaches base station 102, line 602 indicates a gradual increase in signal strength. The sinusoidal characteristic may be due to the superposition of the main signal and the signal reflected from the ground. The graph properties correspond to theoretical calculations.

[0121] The above embodiments are intended to illustrate solutions to the following specific technical problems:

[0122] - By using radio waves in the short millimeter wave range, a "vehicle-to-ground" communication channel with a nominal speed of 10Gbps is provided;

[0123] - Comply with the line-of-sight conditions between the base station on the train line and the radio frequency module installed on the train to ensure that it operates within a short millimeter range;

[0124] - By installing base stations near railway clearance, compliance with regulatory requirements regarding the prohibition of installing third-party equipment within railway clearance is achieved in railway infrastructure construction.

[0125] - By reducing the first Fresnel zone, obstacles are eliminated during the propagation of millimeter waves along railway infrastructure;

[0126] - By using appropriate component base stations and radio frequency modules, ensure operation in commercially developed bands such as V-band, E-band, W-band, F-band, and D-band.

[0127] It should be understood that the above embodiments of the present invention are merely illustrative and should not be construed as restrictive. The present invention may be supplemented with other details, features, and modifications without altering its essential content, as set forth in the independent claims and specified in the dependent claims.

Claims

1. A method for providing high-speed communication on a high-speed railway, wherein a base station connected to an external data transmission network is installed along the train route; the base station is equipped with a narrow-directional antenna capable of communicating with a head radio frequency module and a tail radio frequency module installed on the train, the head radio frequency module and the tail radio frequency module being equipped with narrow-directional antennas and integrated into an internal data transmission network, the base station being positioned along the train route to allow direct visibility between the base station antenna and the antenna of a radio relay module installed on the train, the method comprising the following steps: - Transmit radio waves in the short millimeter wave range on the antennas of the base station and the mobile train radio frequency module; - Establish a communication channel between the first head module and the nearest base station in front of it, and establish a communication channel between the first tail module and the base station closest to it behind it; - Before the train passes the base station located ahead, a communication channel is established between the second head module and the next base station closest to the train; - After the rear of the train passes the base station that was originally located at the front of the train, a communication channel is established between the second rear module and the base station. Furthermore, radio signals exchanged through established communication channels are processed on switching equipment associated with the radio frequency module, providing network equipment on the train with access to external data exchange networks.

2. The method according to claim 1, wherein the antennas of the first and second head modules face the base station located in front of the moving train, and the antennas of the first and second tail modules face the base station located behind the train.

3. The method according to claim 1, wherein the base station antenna is configured to transmit a beamwidth of narrow.

4. The method according to claim 1, wherein the communication channel between the base station and the module installed on the railway train is configured in full-duplex mode, and the channel is divided into frequency and polarization.

5. The method of claim 1, wherein the transmitted radio waves are located in one radio frequency band selected from the group consisting of V-band, E-band, W-band, F-band and D-band.

6. A method for providing high-speed communication on a high-speed railway, wherein a base station connected to an external data transmission network is installed along the train route; the base station is equipped with a narrow-directional antenna capable of communicating with a head radio frequency module and a tail radio frequency module installed on the train, the head radio frequency module and the tail radio frequency module being equipped with narrow-directional antennas and integrated into an internal data transmission network, the base station being positioned along the train route to allow direct visibility between the narrow-directional antenna of the base station and the narrow-directional antenna of a radio relay module installed on the train, the method comprising the steps of: - Transmit radio waves in the short millimeter wave range at frequencies above 40 GHz on the narrow-directional antenna of the base station and mobile train radio frequency module; - Establish a communication channel between the first head module, the first tail module and the base station closest to them located behind them, and at the same time establish a communication channel between the second head module and the nearest base station located in front of it; - Before the front of the vehicle passes the base station located in front, a communication channel is established between the second rear module and the base station located in front of the rear of the vehicle, wherein the second head module has previously communicated with the base station. Furthermore, radio signals exchanged through established communication channels are processed on switching equipment associated with the radio frequency module, providing network equipment on the train with access to external data exchange networks.

7. The method according to claim 6, wherein the narrow-direction antennas of the first head module and the first tail module are oriented toward a base station located behind the moving train, and the narrow-direction antennas of the second head module and the second tail module are oriented toward a base station located in front of the train.

8. A system for providing high-speed communication on a high-speed railway, the system comprising internal and external data exchange networks, wherein, Internal data exchange network integration: The rear radio frequency module, installed at the rear of the train, is equipped with a narrow-directional antenna; A head radio frequency module installed at the front of the train is equipped with a narrow-directional antenna; and A switching device that can process signals from the module and provide access to an external data switching network to network devices associated with the device; External data exchange network combined with base station and narrow-directional antenna, The base station is capable of establishing communication with the rear radio frequency module and the front radio frequency module of the train, and is installed along the train route. Its location allows for direct visibility between the base station antenna and the radio relay module antenna installed on the train. The antennas of the base station and the radio frequency module installed on the train are configured to transmit radio waves in the short millimeter wave range; The first head module is configured to establish a first communication channel with the nearest base station in front of it, and the first tail module is configured to establish a second communication channel with the nearest base station behind it. The second head module and the next base station located ahead of the train are configured to establish a third communication channel before the train passes the base station closest to the first head module. The second tail module and the base station located at the front of the train are configured to establish a fourth communication channel after the train passes the base station at the rear.

9. The system according to claim 8, wherein the antennas of the first head module and the second head module are oriented toward a base station located in front of the moving train, and the antennas of the first tail module and the second tail module are oriented toward a base station located behind the train.

10. The system according to claim 8, wherein the antennas of the first head module and the first tail module are oriented toward a base station located in front of the moving train, and the antennas of the second head module and the second tail module are oriented toward a base station located behind the train.

11. The system of claim 8, wherein the base station is located on a railway catenary support.

12. The system of claim 8, wherein the base station is located on a support between the railway clearance boundary and the railway catenary support closest to the boundary.

13. The system according to claim 8, wherein the base station is connected to the network via an optical fiber communication path.

14. The system of claim 8, wherein each base station and each radio frequency module installed on the train comprises several devices that provide switching, routing, receiving and transmitting of wireless signals.

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