Seamless roaming communication system for mining auxiliary transport vehicle

Abstract

The utility model relates to the technical field of coal mine communication, in particular to a seamless roaming communication system for a mining auxiliary transport vehicle, which comprises a vehicle-mounted network terminal device arranged on a mining trackless rubber-tyred vehicle, and an IAPM fast switching WiFi module is arranged in the vehicle-mounted network terminal device; and the ground network server is connected with the IAPM fast switching WiFi module through a ring network. 802.11 k / v / r network transmission protocols are loaded in the vehicle-mounted network terminal equipment and the base stations, the base station which is closest to the IAPM fast switching WiFi module and has the best signal strength in the base stations is defined as a main connection base station, the next base station is defined as a standby connection base station, the IAPM fast switching WiFi module can be continuously switched to be connected with different main connection base stations when the mining trackless rubber-tyred vehicle travels, and the IAPM fast switching WiFi module can be continuously switched to be connected with the different standby connection base stations when the mining trackless rubber-tyred vehicle travels. And keeping communication with a ground network server. Through the active station switching function of the IAPM fast switching WiFi module and the real-time monitoring and auxiliary control station switching functions of the roaming control service of the server side, data and video uploading in the driving process do not lose packets, and communication is not interrupted.

Description

Technical Field

[0001] This application relates to the technical field of coal mine communication, and in particular to a seamless roaming communication system for mine auxiliary transportation vehicles. Background Art

[0002] The improvement of the intelligence and informatization of auxiliary transportation vehicles is an important direction for accelerating the intelligent development of coal mines. The trackless rubber-tyred vehicle among auxiliary transportation vehicles has the characteristics of being flexible, adaptable, safe, efficient, and having a wide application range due to no track restrictions. It is a relatively advanced auxiliary transportation vehicle for transporting materials, equipment, and personnel. Currently, major coal mines require trackless rubber-tyred vehicles to be equipped with in-vehicle communication terminals that can connect to wireless networks, with functions such as uploading working condition data, monitoring and uploading driving videos, and in-vehicle voice communication, to achieve digital information integration and facilitate the intelligent and informatized management and control of auxiliary transportation vehicles.

[0003] Existing in-vehicle communication terminals for trackless rubber-tyred vehicles, their supporting wireless base stations and network management systems already have basic communication functions. The in-vehicle communication terminals of different manufacturers have different focuses. Generally, they include functions such as uploading vehicle condition data, monitoring and uploading driving videos, and in-vehicle voice communication. Some manufacturers only have one of these functions, while some manufacturers have multiple of these functions; but none of them have the ability of network seamless roaming.

[0004] When a trackless rubber-tyred vehicle is operating underground, it continuously moves between the coverage ranges of different base station networks, and network handover is frequent. If there is no seamless roaming solution, when the vehicle moves from one base station to near the next base station, the signal of the previous base station is very weak but still not disconnected, and it cannot be switched to the nearby base station with a stronger signal in time. Even if it can be switched to a nearby base station for connection, there will be a relatively long reconnection process, resulting in a relatively large and frequent proportion of network disconnections.

[0005] The in-vehicle communication terminal equipment carried by the trackless rubber-tyred vehicle has video transmission and call functions. In the case of frequent network disconnections, it will cause problems such as partial loss of vehicle condition data uploaded, discontinuous driving video upload, and easy interruption during calls, seriously affecting the user experience. Summary of the Utility Model

[0006] The technical problem to be solved by this utility model is that the existing communication system for trackless rubber-tyred vehicles does not have the function of seamless roaming. When operating underground, it is easy to interrupt the signal with the ground terminal, resulting in problems such as discontinuous data transmission and call interruption.

[0007] Therefore, this utility model provides a seamless roaming communication system for mine auxiliary transportation vehicles.

[0008] The technical solution adopted by this utility model to solve its technical problem is:

[0009] A seamless roaming communication system for mine auxiliary transportation vehicles, comprising

[0010] An on-vehicle network terminal device, which is arranged on a mine trackless rubber-tyred vehicle, and an IAPM fast-switching WiFi module is arranged in the on-vehicle network terminal device;

[0011] A ring network, which includes multiple base stations;

[0012] A ground network server, which is connected to the IAPM fast-switching WiFi module through the ring network;

[0013] The IAPM fast-switching WiFi module is alternately connected to multiple base stations in the ring network in sequence.

[0014] Further, the base station in the ring network that is closest to the IAPM fast-switching WiFi module and has the best signal strength is defined as the main connection base station, and the next base station is the standby connection base station. When the mine trackless rubber-tyred vehicle is moving, the IAPM fast-switching WiFi module can continuously switch to maintain connection with different main connection base stations and communicate with the ground network server.

[0015] Further, the IAPM fast-switching WiFi module is connected to one base station at the same time period.

[0016] Further, the IAPM fast-switching WiFi module and the base station adopt the 802.11k / v / r network transmission protocol.

[0017] Further, the service set identifiers of the base stations in the ring network are all the same.

[0018] Further, a data video receiving and storing service module, a SIP call service module, and a roaming control service module are arranged in the ground network server.

[0019] Further, the data video receiving and storing service module

[0020] Further, the SIP call service module is used to realize calls between vehicles and calls between vehicles and the ground dispatching desk.

[0021] Further, the roaming control service module is used to monitor the connection information of the terminal devices hung under the base station in real time.

[0022] The beneficial effects of the present utility model are as follows. In this application, an IAPM fast-switching WiFi module is provided. The IAPM fast-switching WiFi module alternately switches and connects with the base stations in the ring network. Thanks to the active station-switching function of the fast-switching WiFi module of the terminal device, seamless roaming and real-time monitoring of the roaming control service on the server side and the auxiliary control station-switching function are achieved, ensuring that data and video uploads are not packet-lost and calls are not interrupted during driving. Brief Description of the Drawings

[0023] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0024] Figure 1 It is a schematic structural diagram of the seamless roaming communication system for mine auxiliary transportation vehicles in the present utility model.

[0025] In the figure: 1, mine trackless rubber-tyred vehicle; 2, vehicle-mounted network terminal device; 3, IAPM fast-switching WiFi module; 4, main connection base station; 5, standby connection base station; 6, base station N; 7, ring network; 8, ground network server; 9, data video receiving and storage service module; 10, SIP call service module; 11, roaming control service module. Detailed Description of the Specific Embodiment

[0026] Now, the present utility model will be further described in detail in conjunction with the drawings. These drawings are all simplified schematic diagrams, only showing the basic structure of the present utility model in a schematic manner, so they only show the components related to the present utility model.

[0027] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0028] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "linkage" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0029] A seamless roaming communication system for mine auxiliary transportation vehicles includes an on-vehicle network terminal device 2, an underground network base station device, and a ground network server 8.

[0030] The on-vehicle network terminal device 2 is provided with a network connection module supporting seamless roaming (IAPM fast-switching WiFi module 3); the underground network base station device is used to provide a WiFi local area network underground; the ground network server 8 is provided with a data and video receiving service module 9, a voice call service module 10, and a network roaming control service module 11.

[0031] When the mine trackless rubber-tyred vehicle 1 travels underground, the on-vehicle network terminal device 2 searches for and connects to the base station with a stronger signal in real time, uploads the vehicle working condition data and driving video to the ground network server 8, and at the same time registers for voice call service through the SIP protocol. When the vehicle moves to the next base station, it seamlessly switches to the current base station with a stronger signal through the network roaming mechanism and continues to maintain the network connection and voice call service connection.

[0032] Specifically, the on-vehicle network terminal device 2 is installed in the cab of the mine trackless rubber-tyred vehicle 1 and is an on-vehicle communication device for the mine trackless rubber-tyred vehicle 1, used to collect the vehicle working condition data and driving video; the on-vehicle network terminal device 2 integrates the IAPM fast-switching WiFi module 3, which is used to connect to the network provided by the base station. The IAPM fast-switching WiFi module supports multiple modes such as router, bridge, and client. In this project, it is set as the client mode when used as a terminal, supports multiple SSID setting functions, supports the WPA2 authentication function, supports fast roaming, the roaming switching time is less than 50 ms, and supports convenient and fast setting of the roaming switching threshold.

[0033] The underground network base station device is an AP device providing a WiFi environment for the underground local area network, and has functions such as setting the transmission power, channel, encryption method, etc. The underground network base station device includes multiple base stations, and the multiple base stations form a ring network 7. The ring network 7 is connected to the ground network server 8 and is uniformly controlled by the ground network server 8.

[0034] The ground network server 8 is provided with a data video receiving and storing service module 9, a SIP call service module 10, and a roaming control service module 11. Among them, the data video receiving and storing service module 9 is used to obtain vehicle data and driving videos from in-vehicle devices and store them in the server hard disk for retrieving historical data and viewing videos; the SIP call service module 10 is used for in-vehicle calls. After the terminal device is normally connected to the network, it actively requests and registers the SIP service with the server to enable calls between vehicles and between vehicles and the ground dispatching desk; the network roaming control service module 11 is used to monitor the connection information of the terminal devices connected to the base station in real time. Generally, the terminal device actively switches the base station according to the current signal strength and handover station threshold. When the signal strength is weak and reaches the handover threshold condition but the terminal does not actively switch the station, the roaming control service module 11 actively controls the base station to disconnect the terminal from the base station with poor signal and reconnect the terminal to the base station with stronger signal.

[0035] It should be noted that both the IAPM fast-switching WiFi module 3 and the base station are provided with the 802.11k / v / r network transmission protocol. Among them, the 802.11k protocol helps the device discover the access point with the best signal; the 802.11v protocol provides reports on network status information, which helps the device select the best access point during roaming; and the 802.11r protocol is responsible for quickly and securely switching access points, reducing the delay during roaming, thereby optimizing the signal strength, signal sensitivity, and signal quality of the main connection base station 4 and the standby connection base station 5, achieving the effect of switching in an extremely short time and avoiding frequent back-and-forth switching.

[0036] The in-vehicle network terminal device 2 establishes a connection with the nearest main connection base station 4 with the best signal strength through the fast-switching WiFi module 3, uploads the vehicle working condition data and driving videos to the ground network server 8, and at the same time uses the data video receiving and storing service module 9 on the server side to process the data and store the videos; after the in-vehicle network terminal device 2 establishes a connection with the main connection base station 4 through the fast-switching WiFi module 3, it also performs SIP voice registration of the SIP call service module 10 and provides a call link, through which the driver can communicate with the ground.

[0037] It should be noted that the number of base stations in the ring network 7 is N. Define the base station n (n is a positive integer less than N) as the main connection base station 4, and the base station n + 1 as the standby connection base station 5. When the vehicle-mounted network device 2 travels with the trackless rubber-tired vehicle to a position far from the main connection base station 4 (base station n) and close to the standby connection base station 5 (base station n + 1), it switches the base station to reconnect to the standby connection base station 5 (base station n + 1) according to the threshold QRSSI. Since the IAPM fast-switching WiFi module 3 can complete the switching within an extremely short time of 50 ms, it can meet the requirement of seamless switching, avoiding data video upload and call interruption. After the station switch, the original standby connection base station 5 (base station n + 1) rises to the main connection base station 4, and the next base station n + 2 becomes the standby connection base station 5, and so on until the base station N becomes the standby connection base station 5.

[0038] The roaming control service module 11 monitors the connection status between the vehicle-mounted network terminal device 2 and the base station in real time. The roaming control service module 11 monitors the interaction information of the vehicle-mounted network terminal device 2 in a timely manner. When it is determined that the vehicle-mounted network terminal device 2 meets the station-switching condition but the station-switching has not been completed, the roaming control service module 11 actively controls the base station with weak signal to disconnect the connection and enables the base station with strong signal to establish a connection with the terminal device.

[0039] The implementation principle of this application is as follows:

[0040] First, determine the station-switching threshold of the vehicle-mounted network terminal device 2 according to the signal strength value required for stable video upload and call of the vehicle-mounted network terminal device 2 and the signal coverage radius of the base station.

[0041] According to the characteristics of the base station, set the channel. The base station channels are selected and set to channels 1, 6, and 11 according to the principle of reducing mutual interference (the relatively general principle of wireless), and set for automatic switching. Set the same SSID (Service Set Identifier) for all base stations, set a unified encryption method, and set the vehicle-mounted network terminal device 2 to be synchronized with the base station.

[0042] According to the signal coverage range of the base station and the signal reception range of the vehicle-mounted network terminal device 2 (hereinafter referred to as the terminal or terminal device), calculate the layout distance, theoretical radius, and the overlapping area of the signal coverage of two base stations.

[0043] Specifically, since the maximum distance at which the signal strength of the base station and the receiving sensitivity of the terminal can be connected and not disconnected is S, and the maximum distance for the terminal device to normally transmit video and audio is S 0 , at this time there is S 0 < S, so the effective coverage range of the base station is S 0 ;

[0044] To ensure that the terminal device has sufficient handover preparation distance when moving between two base stations, there should be an overlapping coverage area. This distance needs to be adjusted according to the actual usage effect. Assume the distance radius between the two base stations is R, and R < S 0 , the distance between the midpoint of the two base stations and the effective coverage range point is RS 0 , the mine-free rubber-tyred vehicle 1 completes the handover of the base station within RS 0 .

[0045] For example, the effective coverage range of the base station is an area with a radius of S. The signal strength A within this area is -80 dBm, and the distance here is S; while the terminal device can effectively transmit only when the signal strength is -75 dBm or less, and the effective transmission signal strength B is -75 dBm, that is, the distance at which the signal strength of the base station's effective coverage range is -75 dBm is S 0 , when the signal strength is -70 dBm and the terminal is moving, it starts to search for a standby base station with relatively better effect. Denote the signal strength for searching the standby connection base station as C, C = -70 dBm, that is, the distance at which the signal strength of the base station's effective coverage range is -70 dBm is R, and the handover should be completed between RS 0 . If the handover is not completed by the time the distance reaches S, the roaming management service module 11 actively disconnects the main connection base station 4 from the terminal device to facilitate the terminal device to immediately switch to the standby connection base station 5. At this time, the standby connection base station 5 has become the main connection base station 4

[0046] According to the signal strength value required for the terminal device to upload videos and make calls stably, that is, the effective transmission signal strength B is -75 dBm. To avoid frequent handovers, the handover threshold QRSSI should be set as C ≤ QRSSI ≤ B, and the threshold QRSSI is between -70 dBm and -75 dBm

[0047] Thus, when the terminal device, i.e., the mine trackless rubber-tyred vehicle 1, actively establishes a roaming relationship with the base station through the IAPM fast-switching WiFi module 3 during travel, the terminal device continuously maintains network connection and voice call service connection through the network roaming seamless switching mechanism. By establishing a roaming seamless switching mechanism through the IAPM fast-switching WiFi module, on the basis that both the terminal device and the base station device have the roaming basic protocol, a seamless switching mechanism is added. The terminal device constantly searches for the signal strengths of two base stations, connects one of the base stations as the main connection channel, and the other as the backup, and reports the received signal strength situation in real time. When the received signal strength is less than QRSSI, the terminal device actively switches to connect to the backup connection base station 5; the network roaming control service module 11 collects the terminal devices connected to each base station. When the dynamic signal strength of a certain terminal device during movement is between QRSSI and -80 dBm and the station switching has not been completed yet, the main connection base station 4 is immediately disconnected from the terminal device to facilitate the terminal device to immediately switch to the backup connection base station 5. At this time, the backup connection base station 5 has become the main connection base station 4, and so on, to achieve seamless connection between the in-vehicle terminal and the network.

[0048] In summary, this application benefits from the active station-switching function of the IAPM fast-switching WiFi module 3 of the terminal device and the real-time monitoring and auxiliary control station-switching function of the roaming control service on the server side, ensuring that data and video uploads are packet-loss-free and calls are not interrupted during driving.

[0049] Inspired by the ideal embodiments of the present invention described above, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A seamless roaming communication system for mining auxiliary transport vehicles, characterized in that: include, An on-board network terminal device (2), the on-board network terminal device (2) being arranged on a mining trackless rubber-wheeled vehicle (1), and the on-board network terminal device (2) being provided with an IAPM quick-cut WiFi module (3); A ring network (7), the ring network (7) comprising a plurality of base stations; A ground network server (8), wherein the ground network server (8) is connected to the IAPM quick-cut WiFi module (3) via a ring network (7); The IAPM quick-cut WiFi module (3) is connected to a plurality of base stations in the ring network (7) in sequence and alternately.

2. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 1 is characterized in that: A base station in the ring network (7) that is closest to the IAPM quick-cut WiFi module (3) and has the best signal strength is defined as a main connection base station (4), and the next base station is a backup connection base station (5). When the mining trackless rubber-wheeled vehicle (1) is moving, the IAPM quick-cut WiFi module (3) can continuously switch to maintain connection with different main connection base stations (4) and maintain communication with the ground network server (8).

3. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 1 is characterized in that: The IAPM quick-cut WiFi module (3) is connected to a base station at the same time period.

4. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 1, characterized in that: The IAPM quick-cut WiFi module (3) and the base station adopt the 802.11k / v / r network transmission protocol.

5. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 1, characterized in that: The service set identifiers of the base stations in the ring network (7) are all the same.

6. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 1, characterized in that: The ground network server (8) is provided with a data and video receiving and storage service module (9), a SIP call service module (10), and a roaming control service module (11).

7. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 6, characterized in that: The data video receiving and storage service module (9) is used to obtain and store vehicle data and driving video of the mining trackless rubber-tyred vehicle (1).

8. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 6, characterized in that: The SIP call service module (10) is used to realize calls between vehicles and calls between vehicles and ground dispatching stations.

9. The seamless roaming communication system for mining auxiliary transport vehicles according to claim 6, characterized in that: The roaming control service module (11) is used to monitor the connection information of the terminal equipment connected to the base station in real time.

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