Method, device and system for applying induction communication to urban rail system

Abstract

The invention discloses a method, equipment and a system for applying induction communication to an urban rail system, belongs to the field of rail transit, and provides a low-cost, reliable and continuous train-ground and train-train wireless mode by taking existing metal conductors such as an overhead line system, a contact rail, a rail, a metal pipeline and a cable of an urban rail or a newly laid induction line as an induction communication transmission medium. The system can be used as a backup communication mode, meets communication requirements of train dispatching, train operation control and the like, supports data, voice and call transmission, can support two-way transmission, and can be used as an emergency transmission channel.

Description

Technical Field

[0001] This invention belongs to the field of rail transit. Most urban rail vehicle-to-ground communication uses AP hotspots, leaky cables, etc., which are expensive and lack backup continuous vehicle-to-ground communication methods. This invention proposes to use existing metal conductors such as contact networks, contact rails, and tracks along the urban rail line, or newly laid induction lines, as inductive communication transmission media to provide a low-cost and reliable continuous vehicle-to-ground wireless communication method and vehicle-to-vehicle wireless communication method. This can also serve as a backup communication method to meet the communication needs of train dispatching, train operation control, etc. Background Technology

[0002] Currently, the high cost of urban rail vehicle-to-ground communication leads to high construction and maintenance costs. Furthermore, the urban rail vehicle-to-ground communication system is singular and lacks backup continuous vehicle-to-ground communication. In the event of a vehicle-to-ground communication failure, train operation efficiency is low and safety is poor. Therefore, a low-cost, reliable, and continuous vehicle-to-ground communication method is needed to meet the vehicle-to-ground communication requirements of key systems such as dispatching and train operation control.

[0003] According to patent searches, the following patents are mainly related to this invention: Chinese invention patent application number CN201410611014.7, application date November 4, 2014, publication number CN104469801A, publication date March 25, 2015, entitled "A Method for Covering Vehicle-to-Ground Wireless Communication Signals in Urban Rail Transit CBTC," with Shanghai Houze Information Technology Co., Ltd. as the applicant, discloses a method for covering vehicle-to-ground wireless communication signals in urban rail transit CBTC. This method combines leaky cables and smart antennas to achieve vehicle-to-ground wireless communication signal coverage for the urban rail transit CBTC train signaling system. It overcomes the drawbacks of traditional methods based on 802.11x series technology and using radio frequency antennas or leaky waveguides for signal coverage. This invention essentially eliminates the need for active equipment within the track section. By overlapping and covering the base station signals of adjacent stations within the section, it ensures that even if the communication signal equipment of one station fails due to power outages or other reasons, the CBTC system's train-to-ground communication can continue to be maintained. This greatly improves the system's reliability, availability, and maintainability, providing a guarantee for the safe operation of subway trains.

[0004] Chinese utility model patent application number "CN201520442210.6", application date "2015.06.25", publication number "CN204775300U", publication date "2015.11.18", titled "A Vehicle-to-Ground Wireless Communication Radio for Metro CBTC Signaling System Based on 400MHz Frequency", with applicant "Shanghai Houze Information Technology Co., Ltd". This utility model discloses a vehicle-to-ground wireless communication radio for a metro CBTC signaling system based on 400MHz frequency. It includes an M12 type 100 / 1000 MHz adaptive network interface, two backup data transmission channels constructed by an Ethernet data exchange module and a McWiLL communication module respectively, a control center (MCU), a fault weakening logic circuit module, status indicator lights, and working status monitoring circuits, etc. Its working process is to establish a highly reliable bidirectional wireless communication link between the McWiLL network and the ground access equipment for transmitting CBTC data and the working status data of the vehicle-to-ground radio itself. The vehicle-mounted radio also incorporates fault-tolerant safety principles and fault mitigation design, further improving its reliability. This invention addresses the vulnerability to interference present in current vehicle-mounted radios operating under WLAN technology, providing a safe and reliable vehicle-mounted radio for dedicated frequency-based vehicle-to-ground wireless communication systems.

[0005] The aforementioned patents do not achieve a low-cost, reliable, and continuous vehicle-to-ground communication method. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the deficiencies in the existing technology by proposing to provide a low-cost and reliable continuous vehicle-to-ground and vehicle-to-vehicle wireless communication method by using existing metal conductors such as urban rail contact networks, contact rails, tracks, metal pipes, and cables, or by laying new induction lines, as the induction communication transmission medium. This method is used for low-bandwidth vehicle-to-ground and vehicle-to-vehicle wireless communication on the main line, can serve as a backup communication method, meets the communication needs of train dispatching and train operation control, supports data and voice transmission, supports two-way communication, and can serve as an emergency transmission channel.

[0007] Urban rail transit includes subways, trams, light rail, maglev, etc.

[0008] The mainline urban rail power supply has few external connection points for the contact network or contact rail, and each power supply arm is approximately several kilometers long. In contrast, the transmission distance of inductive communication can reach several kilometers. The ground-mounted stations for inductive communication can be set up according to the power supply interruption. The ground-mounted stations for inductive communication can be set up at fixed intervals (intermediate power segments use filtering equipment to achieve continuous transmission). Cross-coverage can be achieved by using different channels or frequency bands in adjacent communication channels, thereby improving reliability. Wires can be laid along the line as inductive lines, which can avoid the influence of the traction power grid or affect the traction power grid, and can be used on non-electrified line sections.

[0009] For areas such as depots, there are many bifurcations and breaks in the rails and overhead contact lines / rails, which cause interference and severe attenuation when using inductive communication. Meanwhile, areas such as depots are generally open ground, so wireless communication can be used for coverage. Wireless communication methods can include microwave radios such as 400MHz radios, or public / private network wireless communication.

[0010] Urban rail lines are equipped with fixed communication radios (referred to as fixed stations, which exchange data with ground control equipment) based on power supply interruption and effective transmission distance of inductive communication. Redundancy or cross-coverage methods can be used. Mobile communication radios (referred to as vehicle-mounted radios, which exchange data with vehicle control equipment) are installed at the front and rear of the train. The front and rear radios can have only the active end working or both ends working, and data exchange is achieved through communication between the front and rear of the train. Ground fixed communication stations can support the access of other terminal devices, such as handheld communication terminals and communication terminals installed on monitoring equipment, for communication needs in on-site operations and other scenarios.

[0011] The vehicle's location is sent to the ground control equipment by the vehicle-mounted positioning device, or the ground control equipment can directly track the vehicle's location. The ground control equipment controls the fixed stations near the vehicle to establish and communicate with the vehicle-mounted station. There is a need for the vehicle-mounted station and the communication terminal to switch between adjacent inductive communication channels. This can be done automatically by monitoring the signal strength or by using positioning (the vehicle-mounted station and the mobile terminal know the configuration of each inductive communication channel on the line).

[0012] The communication frequency band and channel configuration of the inductive communication fixed station can be set and saved in advance. It can be stored on the vehicle in advance or sent to the vehicle through other vehicle-to-ground communication methods (such as transponders). The vehicle control equipment can know the channel frequency band and channel of the ground fixed station based on the vehicle's positioning, and can establish communication faster and more stably. Mobile terminals or handheld radios can automatically search for nearby fixed radios or manually tune and match them based on the signal field strength.

[0013] Inductive communication can serve as an emergency communication channel. Ground control equipment can transmit emergency situations, such as stopping instructions, to all vehicles, a single vehicle, or a group of vehicles through each fixed station. Vehicles can transmit emergency situations to ground control equipment and adjacent vehicles through their onboard radios, and can also indirectly transmit them to other vehicles through ground fixed stations. Emergency situations have higher transmission priority than other communication frames.

[0014] When the fixed station fails, communication can be maintained between the vehicle-mounted stations / mobile terminals in this section, as well as between the vehicle-mounted stations and the mobile terminals.

[0015] Inductive communication can serve as a backup communication method for existing wireless communication. When existing wireless communication fails, it can be switched to inductive communication to realize vehicle-to-ground and vehicle-to-vehicle communication functions.

[0016] Inductive communication has functions such as voice communication, calling, and data transmission.

[0017] Inductive communication supports two-way calls and data transmission between vehicle-mounted radios, mobile communication terminals, and fixed stations, and supports all-call, group call, selective call, and emergency call functions. Inductive communication also supports one-way broadcasting, one-way group calling, and one-way selective calling (including one-way data transmission) from fixed stations to vehicle-mounted radios and communication terminals. Inductive communication also supports one-way calling or data transmission from vehicle-mounted radios / mobile terminals to fixed stations.

[0018] Supports relay communication and call functions.

[0019] The operating frequency is selected based on factors such as transmission distance and the range of available frequency bands, and can be referenced to the 400kHz frequency band used in railway train dispatching.

[0020] Narrowband digital modulation and demodulation techniques can be used for modulation and demodulation in inductive communication to improve spectrum utilization and system capacity.

[0021] The networking of inductive communication can meet the communication needs of urban rail mainline dispatching, train operation control between train and ground, between trains, and on-site construction.

[0022] The beneficial effects of this invention are as follows: This invention belongs to the field of transportation and proposes to use existing metal conductors such as urban rail contact networks, contact rails, tracks, metal pipes, and cables, or newly laid induction lines, as inductive communication transmission media to provide a low-cost and reliable continuous vehicle-to-ground and vehicle-to-vehicle communication method. It is used for low-bandwidth continuous vehicle-to-ground and vehicle-to-vehicle wireless communication on the main line and can serve as a backup communication method to meet the communication needs of train dispatching and train operation control. It supports data, voice, and call transmission, and can support one-way and two-way communication and calls. It can support group calls / group calls / selective calls, and can support broadcast, point-to-point, and point-to-multipoint communication methods. Attached Figure Description

[0023] Figure 1 A schematic diagram of the urban rail inductive communication structure with the fixed platform positioned in the middle of the power supply arm. Figure 2 A schematic diagram of the urban rail inductive communication structure set up for the fixed station based on the end of the power supply disconnection. Figure 3 A schematic diagram of an urban rail inductive communication structure set up for fixed platforms according to a fixed spacing length.

[0024] In the diagram: 1 - Induction line, 2 - Fixed antenna, 3 - Vehicle-mounted antenna, 4 - Induction communication mobile terminal, 5 - Filtering device. Implementation

[0025] The present invention will be further described below with reference to specific embodiments and accompanying drawings: The present invention relates to a method, device, and system for applying inductive communication to urban rail transit systems. Figures 1-3 As shown.

[0026] The following patent implementation method takes the power supply contact network as an example of inductive communication transmission medium. The inductive communication transmission medium can be contact rail, steel rail, newly laid wire, etc.

[0027] When using overhead contact lines or contact rails as the carrier for inductive communication, the overhead contact lines or contact rails for mainline urban rail power supply have few external connection points, and each power supply arm is approximately several kilometers long, while the transmission distance of inductive communication can reach several kilometers. A fixed platform can be set in the middle of each power supply arm. For longer power supply arms, effective coverage can be achieved by adding fixed platforms or relays, and the electrical disconnection can be used as the boundary point of the inductive communication section. When the length of the urban rail power supply arm is less than the effective communication distance of inductive communication, the power supply arm can be used as an inductive communication section, or filtering facilities such as high-voltage filter capacitors can be set at the electrical disconnection point to extend the coverage distance of inductive communication.

[0028] When using contact wire or contact rail as the sensing line, fixed stations can be set up on both sides of the power supply arm. Since the power supply arm is generally located near the station, it is convenient to set up fixed stations and cross-coverage of inductive communication. However, the channels are different, that is, adjacent fixed stations cannot interfere with each other. Vehicle-mounted stations / mobile stations are configured with communication channels according to vehicle positioning or personnel and equipment positioning.

[0029] When a single power supply arm is interrupted by a power outage, it is powered by an adjacent power supply arm. The original power segment is short-circuited. Since adjacent inductive communication zones use different frequency bands and channels, inductive communication is not affected.

[0030] Different channels and frequency bands are used in different inductive communication ranges.

[0031] Wave traps can be installed between the feeder and the contact wire / contact rail to reduce the attenuation and interference of the power supply feeder on the induced signal.

[0032] The fixed station and ground control equipment are configured using redundant communication or ring network communication, and fiber optic communication can be used.

[0033] Inductive communication can extend coverage distance and improve communication signal quality through relay functionality.

[0034] The communication frequency band and channel configuration of the ground station can be set and saved in advance. It can be stored on the vehicle or sent to the vehicle through other vehicle-to-ground communication methods (such as transponders). The vehicle control equipment can learn the channel frequency band and channel of the ground station based on the vehicle's positioning, and establish communication faster and more stably.

[0035] Ground-based fixed stations can upload information to the vehicle's onboard station, including train number / locomotive number, train / locomotive end number, route information, movement authorization, temporary speed limit, etc. The vehicle's onboard station can download information to the ground-based fixed station, including train number / locomotive number, train / locomotive end number, train integrity status, train position, train direction and speed, and the status of the train and train control onboard equipment, etc.

[0036] Mobile terminals or handheld radios can automatically search for nearby fixed radio stations based on signal strength or be manually tuned and matched.

[0037] The above embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the invention, which should be defined by the claims.

Claims

1. A method, device, and system for applying inductive communication to urban rail transit systems, characterized in that: By using existing metal conductors such as contact wires, contact rails, tracks, metal pipes, and cables in urban rail transit, or by laying new conductor induction lines along the tracks as inductive communication transmission media, continuous vehicle-to-ground and vehicle-to-vehicle wireless communication methods can be provided. This can serve as a backup communication method for existing wireless communication, meet the communication needs of train dispatching and train operation control, support data, voice, and call transmission, support one-way and two-way transmission, support group calls / group calls / selective calls, and support broadcast, point-to-point, and point-to-multipoint communication methods. The vehicle can be equipped with a radio at both ends. The radio at the beginning and end of the vehicle can have only the active end working or both ends working, and data can be exchanged through communication between the beginning and end of the train. Engineering vehicles and other equipment are equipped with vehicle-mounted radios for transmitting data, voice, and calls with ground control equipment.

2. A method, device, and system for applying inductive communication to urban rail transit systems, characterized in that: The existing metal conductors such as the contact network, contact rail, track, metal pipes, and cables of the urban rail transit system, or the newly laid conductor induction lines along the track, are used as induction communication transmission media to provide communication and call transmission functions between on-site induction communication mobile terminals or portable induction communication terminals and between them and ground fixed stations. Ground-based fixed communication stations can support the access of other terminal devices for communication and call transmission needs in on-site operations and other scenarios.

3. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: When using overhead contact lines or contact rails as the carrier for inductive communication, fixed stations are arranged according to the power supply interruption and the effective transmission distance of inductive communication. Fixed stations can be set at the middle position of each power supply arm. For longer power supply arms, effective coverage can be achieved by adding fixed stations to optimize the layout or by using relays. The power interruption is used as the boundary point of the inductive communication section. When the length of the urban rail power supply arm is less than the effective communication distance of inductive communication, the power supply arm can be used as an inductive communication section, or a filter device can be set at the power interruption point to extend the inductive communication coverage distance. Onboard stations can be configured with a fixed length, and a filter device can be set at the power interruption point to extend the inductive communication coverage distance. The arrangement of fixed stations can be roughly consistent with the block section. The fixed platform can be set on both sides of the power supply arm, which facilitates the setting of the fixed platform and the cross-coverage setting of inductive communication; The vehicle-mounted radio / mobile terminal matches the communication channel and frequency band based on the vehicle's location or the location of personnel and equipment. Different channels and frequency bands are used in different inductive communication zones, and redundancy or cross-coverage of inductive communication can be adopted; inductive communication can extend the coverage distance and improve the quality of communication signals through relay functions.

4. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: A break in the power supply arm due to other reasons can be bridged by a filter device, preventing low-frequency signals from passing through while allowing inductive communication signals to pass smoothly; a short circuit between adjacent power supply arms due to a fault does not affect communication; wave traps can be installed between the feeder and the contact wire / contact rail to reduce the attenuation and interference of the power supply feeder on the inductive signal; The induction line can be constructed by laying conductors along the line or by using rails or metal pipes. This avoids the influence of the traction power grid or affects the traction power grid, and can be used on non-electrified urban rail lines.

5. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: For depots and stations, there are many bifurcations and breaks in the rails, overhead contact lines / rails, etc. Wireless communication can be used to cover these areas, enabling communication and calling between the train and the ground, between trains, and between field equipment.

6. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: The communication frequency band and channel configuration of the ground station can be set and saved in advance. It can be stored on the vehicle or sent to the vehicle through other vehicle-to-ground communication methods. The vehicle control equipment can know the channel frequency band and channel of the ground station based on the vehicle's positioning, and establish communication faster and more stably. Mobile terminals or handheld radios can automatically search for nearby fixed radios or manually tune and match them based on the signal strength. The vehicle's location is sent from the on-board positioning device to the ground control equipment, or the ground control equipment can directly track the vehicle's location. The ground control equipment can control a fixed station near the vehicle to establish communication with the vehicle's on-board station. Vehicle-mounted radios and communication terminals need to switch between adjacent inductive communication channels. They can switch automatically by monitoring signal strength or by obtaining the inductive communication frequency band and channel through location.

7. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: Inductive communication can serve as an emergency communication channel. Ground control equipment can transmit emergency commands to all vehicles, or to a single vehicle or a group of vehicles, through each fixed station. Vehicles can transmit emergency commands or events to ground control equipment and adjacent vehicles through their onboard radios, and can also indirectly transmit them to other vehicles through ground fixed stations. Emergency transmissions have higher priority than other communication frames. When the fixed station fails, communication and call transmission can be maintained between the vehicle-mounted stations / mobile terminals in this section, as well as between the vehicle-mounted stations and the mobile terminals.

8. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: Inductive communication can serve as a backup communication and call transmission method for existing wireless communication. When existing wireless communication fails, it can switch to inductive communication to realize data, voice and call transmission functions between vehicles and the ground, between vehicles and each other, and between adjacent devices. Inductive communication has functions such as voice communication, calling, and data transmission, and supports relay communication and calling functions; Inductive communication supports two-way calling and two-way data transmission between vehicle-mounted radios, mobile communication terminals, and fixed stations, and supports all-call, group call, selective call, and emergency call functions; inductive communication supports one-way broadcasting, one-way group calling, and one-way selective calling functions from fixed stations to vehicle-mounted radios and communication terminals, as well as corresponding data transmission functions; inductive communication supports one-way calling or data transmission functions from vehicle-mounted radios / mobile terminals to fixed stations; The operating frequency is selected based on factors such as effective transmission distance and the range of selectable frequency bands, and can be referenced to the 400kHz frequency band used in railway train dispatching. Narrowband digital modulation and demodulation techniques can be used for modulation and demodulation in inductive communication to improve spectrum utilization and system capacity.

9. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: The fixed station and ground control equipment are configured using redundant communication or ring network communication, and fiber optic communication can be used. The networking of inductive communication can meet the communication needs of urban rail mainline dispatching, train operation control between train and ground, between trains, and on-site construction.

10. The method, apparatus, and system for applying inductive communication according to claims 1 and 2 to urban rail transit systems, characterized in that: Ground-based fixed stations can upload information to the vehicle's onboard station, including train number / locomotive number, train / locomotive end number, route information, movement authorization, temporary speed limit, etc. The vehicle's onboard station can download information to the ground-based fixed station, including train number / locomotive number, train / locomotive end number, train integrity status, train position, train direction and speed, and the status of the train and train control onboard equipment, etc.

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