JP3720326B2 - Communications system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a communication system, and more particularly, to a communication system constructed over a plurality of structures partitioned into an internal space and an external space.
[0002]
[Prior art]
As a technology in such a field, a communication system is known in which a LAN (Local Area Network) is constructed across a plurality of organized vehicles and information is transmitted and received between the vehicles (for example, Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-275211
[Problems to be solved by the invention]
However, in the communication system described above, since the connection line that connects the LAN built inside the vehicle to the LAN of another vehicle is exposed to the outside of the vehicle, information can be easily obtained by connecting a device to the connection line. Can be accessed. As described above, in a communication system in which communication networks provided in each of the plurality of structures are connected by connection lines, there is a problem in that the security of the connection lines exposed to the outside is low.
[0005]
Therefore, an object of the present invention is to provide a communication system constructed over a plurality of structures and having improved security.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a communication system according to the present invention includes a plurality of structures partitioned into an internal space and an external space, a communication network formed in each of the plurality of structures, and the communication network A connection line connected to the communication network and a first signal voltage level information transmitted and received in the communication network formed in the internal space of the structure is a second signal higher than the first signal voltage level. The voltage level information is converted into voltage level information and transmitted to the connection line, and the second signal voltage level information transmitted from the other structure via the connection line is converted to the first signal voltage level information. And a booster circuit for transmitting to a communication network formed in the internal space of the structure.
[0007]
According to such a configuration, since the information whose signal voltage level is increased by the booster circuit is sent to the connection lines connecting the communication networks formed in each structure, the connection lines exposed to the outside of the structure It is difficult to access information even if a device is connected. Therefore, this communication system has improved security.
[0008]
In the communication system according to the present invention, the plurality of structures may be a plurality of knitted vehicles, and the connection line may be a signal line that connects the vehicles to be connected. .
[0009]
According to such a configuration, since the signal voltage level of the information sent to the connection line connecting the communication network built in the vehicle to the communication network of another vehicle is increased, even if a device is connected to the connection line It is difficult to access information. Therefore, this communication system has high security. In addition to this, noise peculiar to the vehicle is added to the signal transmitted to the signal line of the vehicle. However, since the signal voltage level of the information transmitted to the signal line is increased, the influence of noise is reduced.
[0010]
The communication system of the present invention further includes an in-vehicle monitoring camera that is installed in the internal space of the vehicle and connected to the communication network formed in the internal space of the vehicle, and the in-vehicle monitoring camera is connected. The video information may be transmitted as the above information to a communication network.
[0011]
Since the video from the in-vehicle monitoring camera is related to privacy, security of the communication system is particularly required. Since the security of the communication system having such a configuration is improved, the communication system is suitable as a system for transmitting and receiving images from the vehicle surveillance camera. In addition, even if noise is added to the signal sent to the signal line of the vehicle, the signal voltage level of the information sent to the signal line is increased, so that the influence of noise is reduced, resulting in image disturbance or interruption. Such a phenomenon can be prevented.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A communication system 1 according to a first embodiment of the present invention will be described with reference to the accompanying drawings. In the following description of the embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings in order to facilitate understanding of the description.
[0013]
FIG. 1 is a diagram showing a configuration of a communication system 1 and shows an example in which the communication system 1 is constructed in a plurality of trains 10. The multi-set vehicle 10 includes four railway vehicles, vehicles 12, 14, 16, and 18. Vehicles 12, 14, 16, and 18 have cabins 20, 22, 24, and 26, respectively. The leading vehicle 12 and the rear vehicle 18 have cabs 28 and 30 adjacent to the respective cabins. In-vehicle LANs 32, 34, 36, and 38 are constructed in the vehicles 12, 14, 16, and 18, respectively.
[0014]
Each of the leading vehicle 12 and the rear vehicle 18 includes a hub 40, an in-vehicle monitoring camera 42, a controller 44, a display 46, a keypad 48, and a junction box (hereinafter referred to as “LJB”) 50. Are connected by an Ethernet (registered trademark of Fuji Xerox Co., Ltd.) cable such as a twisted pair cable, so that an in-vehicle LAN 32 and an in-vehicle LAN 38 are constructed. Each of the vehicles 14 and 16 includes a hub 40, an in-vehicle monitoring camera 42, and an LJB 50. The vehicle 14 further includes a recording device 52, and these devices are connected by an Ethernet cable so that the in-vehicle LAN 34, the in-vehicle A LAN 36 is constructed.
[0015]
Two in-vehicle monitoring cameras 42 are provided for each vehicle. The in-vehicle monitoring camera 42 is installed in front of and behind the passenger cabin in each vehicle, and is fixed above the wall portion constituting the passenger cabin. Then, the in-vehicle monitoring camera 42 captures an image in the cabin from the installed position. The in-vehicle monitoring camera 42 is connected to the Hub 40 via a cable and sends out the captured video.
[0016]
The controller 44, the display 46, and the keypad 48 are installed in the cab 28 of the leading vehicle 12 and the cab 30 of the rear vehicle 18, respectively. The controller 44 is connected to the Hub 40 via a cable and receives an image taken by the in-vehicle monitoring camera 42. In addition, a display 46 and a keypad 48 are connected to the controller 44 via a cable, and the controller 44 controls them. The keypad 48 is an operation panel that selects an image to be displayed on the display 46 from images captured by a plurality of in-vehicle monitoring cameras 42 installed in each vehicle.
[0017]
The recording device 52 is a hard disk that stores videos taken by a plurality of in-vehicle monitoring cameras 42 installed in each vehicle.
[0018]
Here, the Hub 40, the recording device 52, and the Ethernet cable for connecting the above-described devices are embedded in the wall or floor of the vehicle, so that these devices and cables cannot be easily accessed from within the cabin. ing.
[0019]
Next, with reference to FIG. 2, the connection line which connects Hub40, LJB50, and LAN of each vehicle mutually is demonstrated in detail. FIG. 2 is an enlarged view showing a partial configuration of the communication system 1. As shown in FIG. 2, the Hub 40 includes a Hub substrate portion 54 and a booster circuit 56.
[0020]
The Hub board unit 54 is a device that relays information via the in-vehicle LAN cable connected to the Hub 40. The booster circuit 56 is connected to the hub substrate portion 54 and the LJB 50. The booster circuit 56 raises the signal voltage level of information transmitted / received by the in-vehicle LAN and transmitted from the hub board portion 54 and transmits the information to the LJB 50. Further, the booster circuit 56 lowers the signal voltage level of the information sent from the LJB 50 and sends it to the hub board portion 54. The signal voltage level of information transmitted and received in the in-vehicle LAN is about 1 to 2 [V], and the signal voltage level of information supplied to the booster circuit is several times the signal voltage level of information transmitted and received in the in-vehicle LAN. And then sent to the LJB 50. The signal voltage level of information sent to the LJB 50 is set to a signal voltage level that is not affected by vehicle-specific noise. This signal voltage level is set to 10 [V], for example. Conversely, the information sent from the LJB 50 has its signal voltage level lowered by the booster circuit 56 to the above-mentioned signal voltage level transmitted and received in the in-vehicle LAN, and sent out to the in-vehicle LAN.
[0021]
The LJB 50 is a device that aggregates the wiring of vehicles. LJB50 is provided in the connection part of the vehicle. The wiring concentrated on the LJB 50 is connected to each of a plurality of jumper lines provided on the LJB 50, that is, a plurality of signal lines connecting the vehicles. The plurality of jumper wires are exposed outside the vehicle. The tip of the jumper wire provided in the LJB 50 is a butting terminal, and when connecting the vehicle to another vehicle, it is connected to the butting terminal of the jumper wire provided in the LJB 50 of the other vehicle. Some of the plurality of jumper lines are reserved lines 58. Information sent from the booster circuit 56 is sent to another connected vehicle via a jumper line. In the communication system 1 according to this embodiment, the information transmitted from the booster circuit 56 is transmitted via the spare line 58 among the jumper lines.
[0022]
Hereinafter, the operation and effect of the communication system 1 according to the present embodiment will be described. In the communication system 1, a video image in a passenger room captured by the in-vehicle monitoring camera 42 is displayed on the display 46 installed in the leading vehicle 12 and the rear vehicle 18 via the Hub 40, and the recording device installed in the vehicle 14. 52.
[0023]
When the image sent from the in-vehicle monitoring camera 42 installed in each vehicle is sent to the in-vehicle LAN of another vehicle, the signal voltage level is raised by the booster circuit 56 provided in the Hub 40, and the LJB 50 and the spare Sent out on line 58. In addition, the booster circuit 56 lowers the signal voltage level of the video transmitted from another vehicle and transmitted via the LJB 50 and the spare line 58. Then, the video whose signal voltage level is lowered is supplied from the booster circuit 56 to the in-vehicle LAN.
[0024]
As described above, the spare line 58 that connects the in-vehicle LANs of each vehicle is exposed to the outside of the vehicle, but the video transmitted to the spare line 58 has a higher signal voltage level, so it corresponds to the Ethernet standard. Even if a commercially available device is connected to the backup line 58, it is difficult to access the above video. Therefore, the communication system 1 has high security. In particular, since the video taken by the in-vehicle monitoring camera 42 is related to privacy, the high-security communication system 1 is suitable.
[0025]
Further, the communication system 1 uses a backup line 58 as a cable for connecting the LANs of the vehicle. That is, the communication system 1 is a suitable system that utilizes existing equipment of the vehicle.
[0026]
Further, when information on the normal signal voltage level in the LAN is sent to the spare line 58, noise peculiar to the vehicle is added to this information. However, in the communication system 1, the signal voltage level of the information sent to the spare line 58 is increased. Therefore, the influence of noise is reduced. As described above, the communication system 1 is a system that is suitable from the viewpoint of safety in in-vehicle monitoring because the influence of noise on the backup line 58 is reduced, so that the image captured by the in-vehicle monitoring camera 42 is not disturbed or interrupted. Has been.
[0027]
The communication system 1 according to the embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and various modifications can be made. First, information transmitted and received by the communication system according to the present invention is not limited to video. Examples of information transmitted and received by the communication system of the present invention include voice information and control information for controlling the vehicle. The connection line that connects the vehicle LANs is not limited to a spare line, and may be an Ethernet cable.
[0028]
The above embodiment relates to an example in which the communication system of the present invention is applied to a plurality of vehicles. The communication system according to the present invention includes a plurality of buildings partitioned into an internal space and an external space. For example, the present invention can be widely applied to an environment where a communication network formed in a structure and a communication network formed in another structure are connected by a connection line exposed to the outside of the structure.
[0029]
【The invention's effect】
As described above, according to the present invention, a communication system in which communication networks constructed in each of a plurality of structures are connected to each other by a connection line exposed to the outside, the security of which is improved. Is provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a communication system according to an embodiment.
FIG. 2 is an enlarged view of a partial configuration of a communication system according to an embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Communication system, 10 ... Multiple formation vehicle, 12, 14, 16, 18 ... Vehicle, 32, 34, 36, 38 ... In-vehicle LAN, 40 ... Hub, 42 ... In-vehicle monitoring camera, 44 ... Controller, 46 ... Display 48 ... Keypad, 50 ... LJB, 52 ... Recording device, 54 ... Hub substrate part, 56 ... Booster circuit, 58 ... Spare line.

Claims (3)

A plurality of structures partitioned into an internal space and an external space;
A communication network formed in each of the plurality of structures;
A connection line for connecting the communication network to the other communication network;
The first signal voltage level information transmitted / received in the communication network formed in the internal space of the structure is converted into second signal voltage level information higher than the first signal voltage level, and the connection The second signal voltage level information transmitted from the other structure through the connection line is converted into the first signal voltage level information and sent to the inside of the structure. A communication system comprising a booster circuit for transmitting to a communication network formed in a space. The plurality of structures are a plurality of knitted vehicles,
The communication system according to claim 1, wherein the connection line is a signal line that connects the connected vehicles. An in-vehicle monitoring camera installed in the interior space of the vehicle and connected to the communication network formed in the interior space of the vehicle;
The communication system according to claim 2, wherein the in-vehicle monitoring camera transmits video information as the information to a connected communication network.

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