JP2011078006A - Communication system and communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system and a communication method that can automatically change setting by radio communication among apparatuses and can achieve easier maintenance when system configurations are changed in communication among a plurality of communication apparatuses that transmit and receive information for traffic control. <P>SOLUTION: In communication among a plurality of communication apparatuses in a radio communication system by time division multiplex communication, each communication apparatus stores route information showing routes of transmission and reception and allocation information that shows the allocation of time slots according to connection configurations among communication apparatuses. When the connection configuration is changed, the communication apparatus in the main station receives route information corresponding to a new connection configuration. When receiving a change notice in time slot from the main apparatus, the other communication apparatus which is a slave station changes allocation to the connection configuration corresponding to that specified by the route information to reset the system and resume transmission and reception. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a communication system including a plurality of communication apparatuses that are installed on a traffic facility on a road or in the vicinity of the traffic facility and perform wireless communication by time division multiplex communication. In particular, the present invention relates to a communication system and a communication method capable of automating communication settings by wireless communication between apparatuses and facilitating maintenance when the system configuration is changed.

  Traffic signal control is planarly controlled by traffic lights on a plurality of intersections. It is necessary to send and receive traffic signal control information between the signal controllers of each traffic light, between the vehicle detectors, and the central device of the control center. Conventionally, the signal controller, the vehicle detector, and the control center are configured to transmit and receive information by wire. FIG. 11 is an upper perspective view of a road showing an example in which traffic signal control information is transmitted and received between devices installed in the vicinity of traffic facilities on the road.

  In FIG. 11, 91 is a communication device installed in the vicinity of the signal controller, and 92 is a communication device installed in the vehicle detector. A sensing result obtained by the vehicle sensor is transmitted from the communication device 92 to another communication device 91. In order to perform signal control in cooperation with the signal controller, information on the detection result is transmitted from the vehicle detector to the communication device 91 from the communication device 92 and further to a device for determining signal control parameters or a traffic control center. . At this time, conventionally, as shown by the broken line in FIG. 11, the communication devices 91 and 92 and other devices are connected by the communication line 90, and the information from the communication device 92 installed in the vehicle detector is the communication device. 91, and information such as signal control parameters is transmitted and received between the communication devices 91.

  On the other hand, for the purpose of reducing the cost of installation work and facilitating maintenance, the communication between devices for traffic control is shifting to be performed wirelessly instead of wired (Patent Documents 1 and 2). Maintenance is relatively easy because wireless communication is possible between devices.

JP 2006-0667462 A JP 2008-205765 A Japanese Patent No. 3450196

  When performing wireless communication between communication devices by time division multiplex communication, each communication device in the same network needs to be able to recognize its own transmission / reception timing. For this purpose, setting of system configuration information such as the number of devices included in the system and a transmission / reception route has been manually performed.

  However, communication devices installed in the vicinity of traffic facilities such as vehicle detectors and signal controllers or in the vicinity thereof usually cover a wide range of several tens to several hundreds meters apart even when adjacent to each other. It is very cumbersome to manually set configuration information for all communication devices belonging to the same network. When a limited number of workers make settings manually for each of a wide range of communication devices, it takes a considerable amount of time, and the system function is stopped during that time. Information transmitted and received between devices for traffic control is information for traffic signal control. If this information cannot be transmitted and received, optimal traffic control cannot be performed, for example, information for signal control from the traffic control center is not sent. Thereby, even if the period when a function stops is about several to several tens of minutes, for example, there is a problem that traffic congestion is caused and traffic is hindered.

  Patent Document 3 discloses an invention in which a base station allocates line resources in response to a request from a terminal station included in the system. However, the present invention is configured to set an assignment to a terminal station that has already been assigned a transmission / reception time slot and can transmit an assignment request to the base station. It is not considered to change the assignment when a new communication device to which transmission / reception timing has not yet been given is added. Therefore, after all, it becomes necessary to make settings corresponding to the addition of a new communication device to each communication device, and the complexity cannot be eliminated.

  The present invention has been made in view of such circumstances, and when the system configuration is changed due to the addition of a new communication device or the like when information for traffic control is transmitted and received wirelessly by time division multiplex communication. Another object of the present invention is to provide a communication system and a communication method capable of automating setting changes by wireless communication between apparatuses and further facilitating maintenance.

  The communication system according to the first aspect of the present invention includes a traffic facility provided at a plurality of points on the road or a plurality of communication devices installed in the vicinity of the traffic facility, and each communication device is between each communication device. A communication system configured to perform time division multiplex communication in which communication is performed in a time slot allocated to itself among a plurality of time slots allocated to communication, wherein each communication device is connected to the plurality of communication devices. Means for storing route information for specifying a transmission / reception route by information for identifying a communication device as a transmission source, a communication device as a transmission destination, and a communication device between the transmission source and the transmission destination according to the configuration; And means for storing allocation information indicating allocation of time slots for communication between the communication devices corresponding to the connection configuration and the path information, wherein the one communication device has the changed connection configuration A means for accepting input of route information for specifying a new transmission / reception route, a means for transmitting a route change notification to another communication device together with the accepted new route information, and a time slot corresponding to itself after transmission. Means for changing the allocation setting, and the other communication device changes the allocation setting of the time slot corresponding to itself based on the allocation information corresponding to the new path information transmitted together with the path change notification. Means are provided.

  In a communication system according to a second invention, in the first invention, the one communication device stops an operation based on the setting before the change and issues a reset command to start the operation based on the setting after the change to the other device. Means for transmitting, and the other communication device is configured to receive the reset command, and to change the assignment setting when the reset command is received, and to execute the reset. .

  The communication system according to a third aspect of the present invention is the communication system according to the second aspect, wherein the other communication device includes means for transmitting a response to a route change notification transmitted from the one communication device, and the one communication device includes: Means for receiving responses from the other communication devices, means for determining whether or not all responses from the other communication devices have been received, and when determining that the responses have been received, A reset command is transmitted.

  A communication method according to a fourth aspect of the present invention includes a plurality of communication devices at or near a traffic facility provided at a plurality of points on the road, and each communication device is assigned to a communication between the communication devices. A communication method for performing time-division multiplex communication in which communication is performed in a time slot assigned to itself among a plurality of time slots, wherein each communication device has a transmission source according to a connection configuration between the plurality of communication devices. Storing path information for specifying a transmission / reception path by information for identifying a communication apparatus, a communication apparatus of a transmission destination, and a communication apparatus between the transmission source and the transmission destination, and further, the connection configuration and the path information The allocation information indicating the allocation of the time slot to the communication between the communication devices corresponding to each of the communication devices is stored, and when one connection device is changed, a new communication device according to the changed connection configuration is changed. Sending Accepts input of route information that identifies the communication route, sends a route change notification to other communication devices together with the new route information accepted, changes the setting of the time slot allocation corresponding to itself after transmission, etc. The communication device is characterized in that the setting of the time slot assignment corresponding to itself is changed based on the assignment information corresponding to the new route information transmitted together with the route change notification.

In the first invention and the fourth invention, traffic equipment including a signal controller, a vehicle detector, a signal controller, etc. provided at each point or a plurality of communication devices fixedly installed in the vicinity thereof are time-division multiplexed communications. To communicate information on traffic signal control wirelessly. Each communication device has route information for specifying a data transmission / reception route corresponding to the current connection configuration of the communication device, and time slot allocation information for communication of each communication device corresponding to the connection configuration and the transmission / reception route. Remember. The plurality of communication devices include a communication device serving as one master station and one or more other slave station communication devices, and the connection configuration is changed by adding a new slave communication device. In this case, route information for specifying a transmission / reception route corresponding to the new connection configuration is input to the communication device of the main station. When a new route information is input, the main station communication device recognizes that the connection configuration changes, such as adding a new communication device, and notifies the change of the connection configuration and the change of the route accompanying this. Is transmitted to the slave communication device, and the slave communication device recognizes the addition of a new communication device based on the notification, and changes the allocation of the time slot based on the routing information received together with the allocation information.
Even if a new communication device is installed, in a system in which each communication device performs wireless communication by time division multiplexing, a new communication device to which a time slot has not yet been assigned is added to itself. Cannot inform the device. On the other hand, in the first invention and the fourth invention, the main station communication device notifies each communication device of the change by causing the main station communication device to input the path information in order to recognize the addition only, In each communication device, the setting is changed to time slot allocation corresponding to communication by a newly added communication device.

In the second invention, the communication device of the master station that has transmitted the change notification to the communication device of the slave station further transmits a reset command to the other communication device of the slave station, and the communication device of the slave station changes after receiving the reset command. Change the allocation setting corresponding to the notification, and execute the reset on your own.
After executing the reset, the slave station communication device receives the synchronization signal transmitted from the master station communication device, which is a communication timing reference in time division multiplex communication, and then performs time division multiplex communication according to the changed assignment. Do. The communication device of the main station can safely change the allocation to the communication time slot in each communication device with a simple configuration of transmitting a reset command after transmitting the change notification.

In the third invention, the slave station communication device transmits a response when receiving the change notification. The master station communication device transmits a reset notification to each device only after receiving responses from all slave station communication devices.
As a result, when some slave station communication devices cannot respond to the change notification, other master stations and slave station communication devices have already changed the time slot assignments to cause a fatal problem. Can be avoided. Changing the time slot assignment due to the connection configuration change affects the entire communication device included in the system. If even a portion of the time slot cannot be changed, stop the assignment change as a whole. Therefore, it is possible to avoid a situation in which a malfunction occurs.

  According to the present invention, in communication between communication devices that transmit and receive information for traffic control, if only one communication device that is a main station is set, the allocation of time slots between communication devices that constitute the communication system is changed. Is performed automatically. Therefore, setting to other communication devices is unnecessary.

  Even in the case where they are adjacent to each other, the communication devices that are installed in the traffic facility or in the vicinity thereof and transmit and receive information relating to traffic signal control may be several tens to hundreds of meters or several hundred meters apart. According to the present invention, when a system configuration is changed, such as when a new communication device is added to the system, time slot allocation in time division multiplex communication is performed by registering settings only in the communication device that is the main station. Can be automated. Therefore, it is not necessary to manually set all communication devices over a wide range, and the maintainability is improved. Further, since the setting is automatically changed, the maintenance work can be speeded up. Therefore, it is possible to prevent troubles such as traffic congestion that may occur due to the suspension of functions due to system changes.

It is an upper perspective view which shows typically the traffic signal control system in this Embodiment. It is a block diagram which shows the internal structure of the communication apparatus which comprises the traffic signal control system in this Embodiment. It is explanatory drawing which shows typically the time slot of the time division multiplex communication by a communication apparatus. It is explanatory drawing which shows the example of the content of the path | route information memorize | stored in each communication apparatus in this Embodiment. It is explanatory drawing which shows the example of the time slot previously allocated to each communication apparatus which is the main station of the existing structure in this Embodiment, the slave station 1, and the slave station 2. FIG. It is a flowchart which shows an example of the process which each communication apparatus of the main station of the existing structure in this Embodiment, the slave station 1, and the slave station 2 performs. It is explanatory drawing which shows the example of addition of the route information in case the communication apparatus of the slave station 3 is newly added to the traffic signal control system in this Embodiment. It is explanatory drawing which shows the example of the change of the allocation of the time slot by the communication apparatus of the slave station 3 being newly added to the traffic signal control system in this Embodiment. It is explanatory drawing which shows the other addition example of route information in case the communication apparatus of the slave station 3 is newly added to the traffic signal control system in this Embodiment. It is explanatory drawing which shows the other example of the change of the allocation of the time slot by the communication apparatus of the slave station 3 being newly added to the traffic signal control system in this Embodiment. It is an upper perspective view of a road showing an example in which traffic signal control information is transmitted and received between devices installed in the vicinity of traffic equipment on a road.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. In the following embodiments, an example in which the communication system according to the present invention is applied to communication between devices related to traffic signal control will be described.

  FIG. 1 is an upper perspective view schematically showing the traffic signal control system in the present embodiment. The traffic signal control system in the present embodiment is installed in the vicinity of a signal controller on the road, and communicates with a communication device 1 and a communication device 2 that transmit and receive signal control information used by the signal controller, and vehicle sensing such as an optical beacon. And a communication device 3 that transmits and receives information used for signal control including a sensing result. The communication device 1 and the communication device 2 at a short distance communicate with each other, and the communication device 2 and the communication device 3 communicate with each other wirelessly.

  Information transmitted / received between the communication devices 1, 2, 3 includes signal control execution information indicating a history of operation of each signal controller, and signal control command information which is an instruction regarding display of a signal lamp color transmitted from the traffic control center. and so on. In addition, there are vehicle information transmitted from the vehicle detector to the traffic control center, VICS information provided from the traffic control center to the vehicle via an optical beacon, and the like. In addition, information on the vehicle number read by the vehicle number reader may be transmitted / received by any one of the communication devices 1, 2, 3 or other similar communication device (not shown).

  In this embodiment, the communication device 1 operates as a master station, the communication device 2 operates as a slave station 1, the communication device 3 operates as a slave station 2, and the communication device 2 (slave station 1) basically operates as the communication device 1 ( A description will be given assuming that the device relays transmission / reception of information between the master station) and the communication device 3 (slave station 2).

  The wireless communication between the communication apparatuses 1, 2 and 3 uses a 2.4 GHz band called an ISM band (Industrial Scientific Medical Band). Use the same frequency band as the frequency for wireless LAN devices based on IEEE802.11b / g (2.4 GHz band: 2.4000 to 2.4835 HGz), and use any of the communication frequency channels divided into 13 or 14 channels. Do it. Here, a device conforming to “ARIB STD-T66 (second generation low power data communication system / wireless LAN system standard)” is also used for 13 channels of the frequency band, “RCR STD-33 (low power data communication system / wireless). A device conforming to the “LAN system standard”) can also use the 14-channel frequency of the frequency band.

  FIG. 2 is a block diagram showing an internal configuration of the communication devices 1, 2, and 3 constituting the traffic signal control system in the present embodiment. The communication devices 1, 2, and 3 have basically the same internal configuration. The communication devices 2 and 3 are denoted by reference numerals corresponding to those of the communication device 1 and detailed description of the internal configuration is omitted.

  The communication device 1 includes a control unit 10, a storage unit 11, and a wireless communication unit 12. At least the communication device 1 also includes an input unit 13. The input unit 13 may not be included in the communication devices 2 and 3.

  The control unit 10 uses a CPU (Central Processing Unit). The control unit 10 is configured to execute various communication control processes described below based on the computer program stored in the storage unit 11. The storage unit 11 uses an EEPROM (Electrically Erasable and Programmable Read Only Memory), a flash memory, or the like, and stores information used for control by the control unit 10 in addition to a computer program executed by the control unit 10. .

  In the present embodiment, the storage units 11, 21, 31 of the communication devices 1, 2, 3 transmit routes for transmitting / receiving information for traffic signal control between the communication devices 1, 2, 3, respectively. Route information that specifies the source, destination, and relay device, and assignment information that is a time slot assignment pattern according to the connection configuration between the communication devices 1, 2, and 3 are stored in advance. Details of the route information and the allocation information will be described later.

  The wireless communication unit 12 includes a frequency channel selection circuit in addition to an antenna, a transmission / reception circuit, a modulation / demodulation circuit, and a modulation / spreading / encoding processing circuit for transmitting and receiving time division multiplex communication radio waves (none of which are shown). ). The wireless communication unit 12 selects any channel from 1CH to 14CH in the frequency band for wireless LAN and realizes communication with other communication devices.

  The input unit 13 is an interface that receives input of information from an operator. Specifically, the connection of the storage medium storing the path information to be added to the storage unit 11 is received and notified to the control unit 10, and the control unit 10 sends the storage unit 11 to the storage unit 11 via the input unit 13. The route information to be added can be read. Note that the input unit 13 may be a switch, a button, or the like indicating numerical information for accepting an operation input, and the control unit 10 may be configured to accept input of route information to be added by a combination of numerical value input operations in the input unit 13.

  As described above, the communication devices 1, 2, and 3 are used for traffic signal control by hardware such as FPGA, ASIC, DPU, etc., in addition to the configuration in which the CPU executes the computer program to realize each function in software. A configuration for realizing wireless communication of information may be employed.

  The communication devices 1, 2, and 3 transmit and receive information used for signal control acquired from traffic equipment such as a signal controller or a vehicle detector based on route information by time division multiplex communication. Specifically, the communication devices 1, 2, and 3 perform transmission and reception at the time slot allocated for each route indicated by the route information between the devices according to the connection configuration.

  FIG. 3 is an explanatory diagram schematically showing a time slot of time division multiplex communication by the communication devices 1, 2, 3. The communication devices 1, 2, and 3 transmit and receive information in units of time slots of 4 milliseconds, for example. A plurality of time slots form one frame. In the present embodiment, each frame includes a “maintenance slot” at the beginning of each frame, and each of the communication devices 1, 2, 3 communicates information indicating a communication frequency channel used for communication in the “maintenance slot” and a response to the instruction. Send and receive maintenance information for. Note that the first “maintenance slot” includes a synchronization signal for frame synchronization. In the first “maintenance slot” for synchronization, the control unit 10 of the communication device 1 that is the master station starts transmission, and the communication devices 2 and 3 that are the slave station 1 or the slave station 2 The head of the frame is recognized by the synchronization signal of “maintenance slot”.

  As shown in FIG. 3, after the “maintenance slot”, a time slot is assigned to each communication from the master station to the slave station 1, the slave station 2, or from the slave station 1, the slave station 2 to the master station. Communicates in the time slot assigned to itself. The allocation of time slots according to the existing connection configuration is set in advance in each of the communication devices 1, 2, and 3. Specifically, among the allocation information indicating a number of allocation patterns stored in the storage unit 11 or the like, allocation according to the connection configuration is selected and set in advance, and the control unit 10 refers to itself The communication timing can be determined.

  The route information stored in the storage units 11, 21, 31 will be described. FIG. 4 is an explanatory diagram showing an example of the contents of route information stored in each of the communication devices 1, 2, and 3 in the present embodiment. The upper part of FIG. 4 schematically shows the connection configuration of the communication apparatuses 1, 2, 3 which are the existing master station and slave stations 1, 2. Note that the solid lines connecting the blocks of the communication devices 1, 2 and 3 of the master station and the slave stations 1 and 2 in FIG. Since 2 and 3 communicate by wireless communication, they are not connected as shown in the figure.

  In FIG. 4, the node numbers of the communication devices 1, 2, 3 are shown below the blocks of the communication devices 1, 2, 3. The master station is “0”, the slave station 1 is “1”, and the slave station 2 is “2”. The route information indicates a route number for identification for each route, and a node number indicating a transmission source, a destination, and a relay device when information is transmitted and received on each route. Further, as shown in FIG. 4, each route information can be stored in association with information as remarks.

  In the example shown in FIG. 4, the route with the route number “1” has the transmission source node “0”, that is, the master station communication device 1, and the destination node “2”, that is, the slave station 2 communication device 3. Is shown. In the route having the route number “1”, the communication device 2 of the slave station 1 of the node “1” is relayed when data is transmitted / received from the communication device 1 of the node “0” to the communication device 3 of the node “2”. . On the contrary, in the transmission / reception of data from the communication device 3 of the node “2” to the communication device 1 of the node “0”, the transmission source and destination of the route having the route number “1” may be reversed.

  In association with the connection configuration as shown in FIG. 4, the storage units 11, 21, 31 store allocation information indicating allocation of time slots for transmission / reception between the communication devices corresponding to the connection configuration. ing. That is, in the present embodiment, in the case of the connection configuration as shown in FIG. 4, the communication devices 1, 2, and 3 transmit and receive information according to the time slot assignment as shown in FIG.

  FIG. 5 is an explanatory diagram showing an example of time slots allocated in advance to each of the communication apparatuses 1, 2, and 3 that are the master station, the slave station 1, and the slave station 2 in the present embodiment. This corresponds to the connection configuration shown in FIG. 4 which is an initial existing configuration. Each rectangle in FIG. 5 represents a time slot, and represents a “maintenance slot” in which maintenance information is transmitted and received by hatching. FIG. 5 shows which of the master station, the slave station 1 and the slave station 2 is a sender and a receiver below each slot. In FIG. 5, “S” means transmission by the corresponding device, and “R” means reception by the corresponding device. Two numbers after “S” or “R” indicate a source node number and a destination node number, and indicate which of the routes indicated by the route information is data transmission / reception. Specifically, “S01” indicates that the transmission source is the communication device 1 having the node number “0” and the destination is the communication device 2 having the node number “1”.

  In the example shown in FIG. 5, the first time slot of frame k is assigned as a “maintenance slot”, and the communication device 1 that is the master station transmits (S) in the time slot, and the communication device that is the slave station. 2 and 3 receive (R).

  As shown in FIG. 5, one frame (frame k) includes a “maintenance slot” from the master station to the slave station 1, a time slot for uplink and downlink for each information path, and the slave station 1 to the slave station 2. The “maintenance slot” and the time slot for uplink and downlink for each information path. The “maintenance slot” is configured to switch between upstream (from the slave station to the master station) and downstream (from the master station to the slave station) for each frame, and in the “maintenance slot” of the k + 1th frame, from the slave station 2 Maintenance information is transmitted to the slave station 1 and from the slave station 1 to the master station. The number of “maintenance slots” in one frame is not limited. Therefore, a configuration may be adopted in which four “maintenance slots” are included so that transmission / reception of maintenance information between the master station, slave station 1 and slave station 2 is completed within one frame.

  Also, as shown in FIG. 5, after the “maintenance slot”, first, the time slot “3” has the transmission source as the node “0”, the destination as the node “1”, and the signal controller in the vicinity of the communication device 1. Is assigned to transmission from the communication device 1 of the master station to the communication device 2 of the slave station 1 such as status information indicating the control status in FIG. In the next time slot “4”, the information that the source is the node “0” and the destination is the node “2” is assigned to the transmission for relay from the communication device 1 of the master station to the communication device 2 of the slave station 1. ing. The time slot “5” is assigned to relaying information with the transmission source node “0” and the destination node “2” by the communication device 2 of the slave station 1, that is, transmission to the communication device 3 of the slave station 2. In the subsequent time slots “6” to “8”, information such as the state information indicating the control state of the signal controllers in the vicinity of the communication devices 2 and 3 and the sensing results are transmitted from the slave stations 1 and 2 to the master station. Assigned to be.

  The communication apparatuses 1, 2, and 3 having the existing connection configuration as shown in FIG. 2 and FIG. 4 perform wireless communication based on the assigned time slots as shown in FIG. However, a new communication device may be added to the configuration of the signal control system. In order to add a new communication device to the system and perform communication by time division multiplex communication, conventionally, each communication device can be assigned with a time slot allocation as shown in FIG. It was set manually.

  On the other hand, in the signal control system according to the present embodiment, the communication devices 1, 2, and 3 of the master station and the slave stations 1 and 2 perform processing as shown in the following flowchart. Thereby, additional installation work becomes easy.

  FIG. 6 is a flowchart showing an example of processing performed by each communication device 1, 2, 3 of the master station, slave station 1, and slave station 2 of the existing configuration in the present embodiment. Each communication device 1, 2 and 3 repeatedly executes the processing procedure shown below.

  Both the communication device 1 of the master station and the communication devices 2 and 3 which are the slave station 1 and the slave station 2 execute communication in the existing configuration shown in FIG. 2 and FIG. 4 according to the time slot assignment shown in FIG. (Steps S101 and S102).

  Here, an operator who intends to add a new communication device to the signal control system installs the newly added communication device at or near a predetermined traffic facility. The newly added communication device has the same configuration as the communication devices 2 and 3, and stores route information and allocation information in the storage unit. The worker causes a new communication device to start wireless communication by time division multiplex communication in accordance with the route and time slot assignment according to the added system configuration (connection configuration). Then, the worker causes the new communication device to input the same information as the route information and the allocation information stored in correspondence with the added system configuration from the input unit 13 of the main station communication device 1. . With the input from the input unit 13 as a trigger, the following processing is executed in the communication devices 1, 2, and 3.

  The communication apparatus 1 of the main station determines whether or not the route information newly added is received by the control unit 10 via the input unit 13 (step S103). If the communication device 1 determines that it does not accept newly added route information (S103: NO), it returns the process to step S101 and continues communication in the existing configuration.

  When determining that the newly added route information has been received via the input unit 13 (S103: YES), the main station communication device 1 identifies the allocation information corresponding to the added route information (step S104). ). Specifically, the connection configuration is specified by the transmission source, the destination, and the node number of the relay device included in the route information, and the allocation information corresponding to the specified connection configuration is specified. A specific example will be described later.

  The communication device 1 of the master station sends a change notification indicating that the connection configuration has been changed, such as adding a device, based on the added route information, to the communication devices of the slave stations 1 and 2 by the wireless communication unit 12. 2 and 3 (step S105). At this time, the communication device 1 also transmits the added route information together with the change notification (S105). The transmission timing is a “maintenance slot” for maintenance information from the communication apparatus 1 in the existing configuration. At this time, the data may be transmitted to each of the slave stations 1 and 2 using “maintenance slots” in different frames over a plurality of frames.

  Whether or not the communication devices 2 and 3 of the slave stations 1 and 2 have received a route change notification from the master station in the “maintenance slot” during the communication in the existing configuration (S102). Is determined (step S106). If the communication devices 2 and 3 determine that the route change notification has not been received (S106: NO), the processing returns to step S102, and communication with the existing configuration is continued.

  When the communication devices 2 and 3 of the slave stations 1 and 2 determine that the route change notification has been received (S106: YES), the wireless communication units 22 and 32 use the "maintenance slot" to the communication device 1 of the master station. A response is transmitted (step S107). The response may be transmitted in a “maintenance slot” of a frame different from the frame including the “maintenance slot” in which the route change notification is transmitted.

  At this time, in the communication devices 2 and 3 of the slave stations 1 and 2, whether or not the allocation information corresponding to the new route information is stored in the storage units 21 and 31, and whether or not the allocation of the time slot can be changed Based on such determination, it may be configured to transmit a response after determining whether or not it is possible to cope with the change of the route. At this time, the communication devices 2 and 3 transmit a response to the communication device 1 of the main station only when it is determined that the change of the route can be handled.

  After transmitting the route change notification (S105), the master station communication device 1 determines whether or not responses have been received from all the slave station communication devices 2 and 3 included in the existing configuration (step S108). ). If the communication device 1 determines that it has not received responses from all slave stations (S108: NO), it returns the process to step S108 and waits until it determines that all responses have been received.

  If a certain upper limit period has elapsed without receiving responses from all slave stations in the existing configuration in step S108, the communication device 1 responds to a change in connection configuration accompanying the addition of a new communication device. If it is not possible, notification may be made using a display unit, a voice output unit, or the like. The operator can recognize that the change in the connection configuration cannot be automatically handled based on the display content on the display unit or the output audio content.

  If the communication device 1 of the master station determines that it has received responses from all the communication devices 2 and 3 of the slave stations in step S108 (S108: YES), a reset command for commanding reset execution to the slave stations 1 and 2 (Step S109), and reset itself (step S110). Then, the communication apparatus 1 of the main station changes the allocation based on the allocation information specified in step S105 (step S111) and ends the process.

  Specifically, in step S111, the communication device 1 reads the specified allocation information and sets to perform communication according to the time slot allocation indicated in the allocation information specified in step S105. That is, it recognizes the timing of its own transmission / reception time slot. Thereafter, the changed connection configuration becomes the existing configuration, and execution is started from the process of step S101.

  On the other hand, the communication devices 2 and 3 of the slave stations 1 and 2 transmit a response in step S107 and specify the allocation information corresponding to the route information transmitted from the master station from the storage units 21 and 31 (step S112). . Specifically, as described above, the communication devices 2 and 3 identify the connection configuration based on the transmission source, destination, and node number indicating the relay device included in the transmitted route information, and associate them with the identified connection configuration. The assigned information is read from the storage units 21 and 31. Note that step S112 may be a procedure before transmission of the response in step S107.

  The communication devices 2 and 3 of the slave stations 1 and 2 specify the allocation information of the allocation of the time slot corresponding to the route after the change, and do not change the allocation yet, but by the wireless communication units 22 and 32 Then, it is determined whether or not a reset command is received from the main station communication device 1 (step S113). If the communication devices 2 and 3 determine that the reset command has not been received (S113: NO), the process returns to step S113 and waits until the reset command is received.

  Here, when the communication devices 2 and 3 wait for a certain upper limit period without receiving the reset command from the communication device 1 of the main station, the time required for the change of the connection configuration and the communication associated therewith is changed. A configuration may be adopted in which it is determined that the change of the slot assignment has been stopped, and the communication returns to step S101 to continue the communication in the existing configuration. As described above, when some of the slave stations cannot cope with the change of the route, the change of the allocation of the time slot in the frame cannot be executed, and the communication is returned to the existing configuration.

  If it is determined that the reset command is received in step S113 (S113: YES), the communication devices 2 and 3 execute the reset (step S114), and change the allocation based on the allocation information specified in step S112. (Step S115), the process ends. Thereafter, the connection configuration after the change of the route becomes the existing configuration, and the execution is started from the process of step S102.

  An example in which the time slot assignment is automatically changed when a new communication device is added and the connection configuration is changed by the processing procedure shown in the flowchart of FIG. 6 will be described with a specific example. .

  FIG. 7 is an explanatory diagram showing an example of adding route information when a communication device of the slave station 3 is newly added to the traffic signal control system according to the present embodiment. The configuration of the explanatory diagram of FIG. 7 is the same as that of FIG.

  As shown in FIG. 7, the newly added communication device of the slave station 3 is connected to the communication device 3 of the slave station 2 so that the master station and the slave stations 1 to 3 are in series. In response to this, the route information of the route number “3” surrounded by the thick ruled line in FIG. 7 is input to the communication device 1 of the main station. The communication device 1 of the master station accepts new route information (S103: YES), and in addition to the existing nodes “0”, “1”, “2”, based on the destination node number “3” in the route information. Recognize that new equipment will be added. Then, the communication device 1 communicates with the added destination node number “3” from the communication device 1 itself with the source node number “0” based on the route information of the newly added route number “3”. Since the route to the device passes through the communication devices 2 and 3 with the node numbers “1” and “2” as relay devices, the connection configuration of the node from the main station is “0” → “1” → “2” → It can be specified that the serial configuration is “3”. The communication device 1 identifies allocation information associated with a connection configuration in which the identified four nodes are connected in series (S104).

  As shown in FIG. 7, the route information includes remark information. The communication device 1 may recognize that the route has been added based on the remark information. If the node number of the relay device is changed even if the source and destination node numbers are the same due to the change in the connection configuration, information such as “change” is added to the remarks information of the corresponding route information. Include it. As a result, the communication device 1 can quickly recognize without any mistake that the route has been changed although there is no slave station to be added.

  FIG. 8 is an explanatory diagram showing an example of changing the allocation of time slots due to the addition of the communication device of the slave station 3 to the traffic signal control system according to the present embodiment. The configuration of the explanatory diagram of FIG. 8 is the same as that of FIG. 5, and shows that the time slot allocation shown in FIG. 5 is changed to the time slot allocation shown in FIG. Yes.

  The changed time slot assignment shown in FIG. 8 corresponds to the connection configuration shown in FIG. In the example shown in FIG. 8, the number of information time slots in one frame is increased corresponding to the addition of the communication device of the slave station 3 as in the connection configuration shown in FIG. Specifically, in an arbitrary k′-th frame after the change, the “maintenance slot” from the master station to the slave station is incremented by one for the slave station 3, and the time slots “1” to “3” are “maintenance”. "Slot".

  Further, as shown in FIG. 8, in the third time slot for information, that is, in the time slot “6”, the communication device 1 with the node number “0” as the main station, the communication device with the node number “3”, It is shown that a transmission / reception time slot corresponding to the transmission / reception route of the route number “3” is inserted. In the connection configuration after the change, the communication device 2 of the slave station 1 with the node number “1” is used as a relay device between the communication device 1 with the node number “0” and the communication device of the node “3” as the slave station 3. And the communication device of the slave station 2 with the node number “2” exists. Therefore, transmission / reception time slots including a relay corresponding to the transmission / reception route of the route number “3” are inserted into the time slots “6”, “8”, “9”, “10”, “12”, and “15”.

  FIG. 9 is an explanatory diagram showing another example of route information when a communication device of the slave station 3 is newly added to the traffic signal control system according to the present embodiment. The configuration of the explanatory diagram of FIG. 9 is the same as that of FIG. 4 and FIG.

  In the example shown in FIG. 9, the newly added communication device of the slave station 3 is directly connected to the master station. In response to this, the route information of the route number “3” surrounded by the thick ruled line in FIG. 9 is input to the communication device 1 of the main station. The communication device 1 of the master station accepts new route information (S103: YES), and in addition to the existing nodes “0”, “1”, “2”, based on the destination node number “3” in the route information. Recognize that new equipment will be added. Then, the communication device 1 communicates with the added destination node number “3” from the communication device 1 itself with the source node number “0” based on the route information of the newly added route number “3”. Since there is no relay device in the route to the device (“0”), the node connection configuration from the main station is “0” → “1” → “2” and “0” → “3”. The connection configuration can be specified. The communication device 1 identifies allocation information associated with the identified connection configuration (S104).

  FIG. 10 is an explanatory diagram showing another example of changing the allocation of time slots due to the addition of the communication device of the slave station 3 to the traffic signal control system according to the present embodiment. The configuration of the explanatory diagram of FIG. 10 is the same as the explanatory diagram of FIG. 5, and shows that the time slot allocation shown in FIG. 5 is changed to the time slot allocation shown in FIG. Yes.

  The changed time slot allocation shown in FIG. 10 corresponds to the connection configuration shown in FIG. In the example shown in FIG. 10, the number of information time slots in one frame is increased corresponding to the addition of the communication device of the slave station 3 as in the connection configuration shown in FIG. Specifically, in an arbitrary k ″ th frame after the change, the “maintenance slot” from the master station to the slave station is increased by one for the slave station 3, and the time slots “1” to “3” are “maintenance”. "Slot".

  Further, as shown in FIG. 10, in the fourth time slot for information, that is, in the time slot “7”, the communication device 1 having the node number “0” and the communication device having the new node number “3” as the main station. It is shown that a transmission / reception time slot corresponding to the transmission / reception route with the path number “3” between and is inserted. In the connection configuration after the change, since the communication device 1 with the node number “0” and the communication device with the node “3” as the slave station 3 are directly connected, the time slots “7” and “8” A direct transmission / reception time slot corresponding to the transmission / reception route of the route number “3” is inserted.

  As described above, in this embodiment, when there is a change in the system in communication between communication devices that transmit and receive traffic control information, the time slot allocation is changed by setting route information only to the main device. Is automatically performed, and setting to other slave devices is unnecessary. Thereby, it is not necessary to individually perform setting change operations in the communication devices 1, 2, and 3 separated by several tens to hundreds of tens of meters and several hundreds of meters, and the maintainability is improved. Automation enables changes more quickly than when people move and work, and can prevent troubles such as traffic congestion that may occur due to the suspension of functions when the system is changed.

  In addition, since the communication apparatus 1 of the master station changes the allocation of the time slot only when there is a response from all the slave stations in response to the setting change, the assignment cannot be changed by the slave station even in part. Nevertheless, avoid forcibly changing it. Eventually, the possibility of having to change the setting in all communication devices can be reduced.

  The disclosed embodiments should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1, 2, 3 Communication device 11, 21, 31 Storage unit 12, 22, 32 Wireless communication unit 13 Input unit

Claims (4)

Including a plurality of communication devices installed at or near the traffic facilities provided at a plurality of points on the road, and each communication device has a plurality of time slots allocated to communication between the communication devices. A communication system adapted to perform time division multiplex communication in which communication is performed in a time slot assigned to itself,
Each communication device
A path for specifying a transmission / reception path by information for identifying a communication apparatus of a transmission source, a communication apparatus of a transmission destination, and a communication apparatus between the transmission source and the transmission destination according to a connection configuration between the plurality of communication apparatuses Means for storing information;
Means for storing allocation information indicating allocation of time slots for communication between the communication devices corresponding to the connection configuration and the path information;
One communication device is
Means for accepting input of route information for identifying a new transmission / reception route according to the changed connection configuration;
Means for transmitting a route change notification to another communication device together with the received new route information;
And a means for changing the time slot assignment setting corresponding to itself after transmission,
Another communication apparatus includes means for changing the setting of time slot allocation corresponding to itself based on allocation information corresponding to new path information transmitted together with a path change notification. The one communication device includes means for stopping the operation based on the setting before the change and transmitting a reset command to start the operation based on the setting after the change to the other device,
The other communication device is:
Means for receiving the reset command;
The communication system according to claim 1, wherein when the reset command is received, the assignment setting is changed and the reset is executed. The other communication device includes means for transmitting a response to the route change notification transmitted from the one communication device,
The one communication device is:
Means for receiving responses from the other communication devices, respectively;
Means for determining whether or not all responses from the other communication devices have been received;
The communication system according to claim 2, wherein the reset command is transmitted to the other communication device when it is determined that it has been received. A traffic facility provided at a plurality of points on the road or a plurality of communication devices in the vicinity of the traffic facility, and each communication device is itself in a plurality of time slots allocated for communication between the communication devices. A communication method for performing time division multiplex communication in which communication is performed in a time slot assigned to
Each communication device
A path for specifying a transmission / reception path by information for identifying a communication apparatus of a transmission source, a communication apparatus of a transmission destination, and a communication apparatus between the transmission source and the transmission destination according to a connection configuration between the plurality of communication apparatuses Remember the information, and
Storing allocation information indicating allocation of time slots for communication between the communication devices corresponding to the connection configuration and the path information;
One communication device is
When the connection configuration is changed, it accepts input of route information that identifies a new transmission / reception route according to the changed connection configuration,
Along with the received new route information, send a route change notification to other communication devices,
Change the time slot assignment setting corresponding to you after sending,
The other communication device changes the setting of the time slot assignment corresponding to itself based on the assignment information corresponding to the new route information transmitted together with the route change notification.

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