JP6951530B2 - Server device and its control method, and program - Google Patents

Description

The present invention relates to a server device that provides a dynamic map for automatic driving of a vehicle by utilizing edge computing, a control method thereof, and a program.

A dynamic map (high-precision three-dimensional map) is being studied as an elemental technology for realizing automatic driving at a level that does not require a driver's driving operation in a vehicle such as a passenger car. In addition, consideration is being given to using Multi-access Edge Computing (MEC), which is being standardized by ETSI (European Telecommunications Standards Institute), to provide dynamic maps to moving vehicles. ing. When using MEC, server devices (MEC servers) distributed near the edge of the mobile network (for example, between the base station and the core network) are placed in the cell of the base station connected to the server device. Provides a dynamic map of the narrow area for the vehicle. This is expected to reduce, for example, the network load associated with communication between a cloud server that provides a wider dynamic map and a vehicle.

In the transmission of the dynamic map between the vehicle and the MEC server, large-sized data is transmitted and data with a short update frequency is transmitted. In order to realize automatic traveling of the vehicle using such a dynamic map, it is necessary to prevent deterioration of communication quality in the wireless transmission section between the base station and the vehicle. Non-Patent Document 1 proposes a technique for reducing communication errors in vehicle-to-vehicle communication and road-to-vehicle communication. Specifically, each vehicle transmits the communication success rate in each geographical area divided into meshes to the server device, acquires the heat map information of the communication success rate generated by the server device from the server device, and communicates. Carry out vehicle-to-vehicle communication and road-to-vehicle communication in areas with a high success rate. Communication errors are reduced by performing communication in an area (mesh) where the communication success rate is high in this way.

“Reception success rate calculation algorithm based on received signal in V2V communication,” IEICE General Conference, B-17-12, March 2017

However, in the above-mentioned conventional technique, when a large number of vehicles communicate with the MEC server at the same time in a region where the communication success rate is high, the load on the network may be locally increased due to the increased traffic. As a result, congestion and communication delays occur in the network, which can lead to communication errors in communication between the vehicle and the MEC server.

The present invention has been made in view of the above-mentioned problems. An object of the present invention is to provide a technique capable of leveling a network load associated with communication between a server device that provides a dynamic map and a vehicle by using edge computing.

The server device according to one aspect of the present invention is a server device connected between a plurality of base stations and a core network, and is a communication indicating a communication status in each of a plurality of cells corresponding to the plurality of base stations. An acquisition means for acquiring status information, and a generation means for generating heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the communication status information acquired by the acquisition means. Among the vehicles traveling in the plurality of cells, one or more vehicles that transmit data used for updating the dynamic map provided for automatic traveling of the vehicles in the plurality of cells are generated. It is characterized in that the one or more vehicles determined based on the heat map information generated by the means are provided with requesting means for requesting the transmission of the data to the server device.
The server device according to another aspect of the present invention is a server device connected between a plurality of base stations and a core network, and determines the communication status in each of the plurality of cells corresponding to the plurality of base stations. Generation that generates heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the acquisition means for acquiring the indicated communication status information and the communication status information acquired by the acquisition means. Means and one or more of the vehicles traveling in the plurality of cells that transmit data used to update the dynamic map provided for automatic travel of the vehicles in the plurality of cells. It is characterized in that it is determined based on the heat map information generated by the generation means, and is provided with a requesting means for requesting a vehicle other than the determined vehicle to stop transmitting the data to the server device. ..

According to the present invention, it is possible to level the network load associated with the communication between the server device that provides the dynamic map and the vehicle by using edge computing.

The figure which shows the network configuration including the MEC server which concerns on one Embodiment. The figure which shows the example of the structure and contents of the dynamic map which concerns on one Embodiment. The conceptual diagram which shows the example of the heat map information generated in the MEC server which concerns on one Embodiment. The block diagram which shows the hardware configuration example of the MEC server which concerns on one Embodiment. The block diagram which shows the functional structure example of the MEC server which concerns on one Embodiment. The figure which shows an example of the situation in the cell of each eNB which concerns on one Embodiment. The figure which shows the example of the usage state of the communication resource (communication band) which concerns on one Embodiment. The sequence diagram of the communication between the vehicle and the MEC server which concerns on one Embodiment. The sequence diagram of the communication between the vehicle and the MEC server which concerns on one Embodiment. The figure which shows the example of the communication status information which concerns on one Embodiment. The figure which shows an example of the situation in the cell of each eNB which concerns on one Embodiment.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In each of the following figures, components that are not necessary for the description of the embodiment will be omitted from the drawings.

In the embodiments described below, an LTE (LTE / LTE-Advanced) network is assumed as an example of a mobile network to which the present invention is applied. The present invention may be applied to mobile networks other than LTE networks. For example, the present invention may be applied to a 5th generation (5G) mobile network whose standardization is being promoted in the 3rd generation partnership project (3GPP).

<Network configuration>
FIG. 1 is a diagram showing an example of a network configuration including a MEC server 10 which is a server device according to an embodiment of the present invention. The LTE network assumed in the present embodiment is composed of an E-UTRAN (Evolved Universal Terrestrial Radio Network) which is a radio access network and an EPC (Evolved Packet Core) which is a core network. Each E-UTRAN is composed of a large number of base stations (base station devices) connected to the EPC via the S1 interface. In LTE, a base station is referred to as an eNodeB (evolved NodeB) (hereinafter, "eNodeB" is referred to as "eNB").

The MEC server 10 is a server device for edge computing (MEC in this embodiment). As shown in FIG. 1, the MEC server 10 (each of the MEC servers 10a and 10b) is connected between a plurality of base stations (eNB) and a core network (EPC) 20. The MEC server 10 manages a plurality of cells (corresponding to the plurality of eNBs) within the communication range of each of the plurality of connected eNBs, and the MEC server 10 is used for automatic driving of the vehicle in the plurality of cells. Provides a dynamic map of. In addition, each vehicle traveling in the cell is equipped with an automatic traveling system for performing automatic traveling using a dynamic map.

<Dynamic map>
FIG. 2A is a diagram showing an example of the configuration of the dynamic map, and FIG. 2B is a diagram showing an example of the details of the data of each item constituting the dynamic map. The dynamic map is composed of data of a plurality of items having different contents, and the data of each item is updated at an update frequency according to the contents. In the present embodiment, as shown in FIG. 2A, the dynamic map is composed of static information (point cloud data), quasi-static information, quasi-dynamic information, and dynamic information.

The point cloud data included in the dynamic map is data indicating the three-dimensional coordinates of the object (indicating the three-dimensional coordinates of the points on the surface of the object), and is updated at a monthly update frequency. For updating the point cloud data in the MEC server 10, the point cloud data acquired by the vehicle provided (uploaded) from the moving vehicle (automatic traveling system) can be used. In the present embodiment, the MEC server 10 requests the vehicle traveling in the cell managed by the MEC server 10 to transmit the point cloud data used for updating the dynamic map held for provision to the vehicle. do. The automatic traveling system of a moving vehicle acquires point cloud data related to objects around the vehicle by measurement using a laser scanner, and acquires the acquired point cloud data in response to a transmission request from the MEC server 10. Send to MEC server 10.

The quasi-static information, quasi-dynamic information, and dynamic information included in the dynamic map are examples of specific information regarding the road conditions around the vehicle, and are updated with a short update frequency of hours, minutes, or seconds. As shown in FIG. 2B, the quasi-static information and the quasi-dynamic information include at least information on traffic regulation and traffic congestion around the vehicle, and the dynamic information includes vehicles, pedestrians and pedestrians around the vehicle. Contains at least signal information. Quasi-static information, quasi-dynamic information and dynamic information need to continue to be provided to the vehicle at relatively short time intervals while the vehicle is running in order to realize automatic driving.

The MEC server 10 may individually provide the data of each item shown in FIG. 2 to the vehicle, or may collectively provide the data of all the items to the vehicle. Further, at least a part of the dynamic map is provided to the vehicle from the cloud server located in the external network (for example, packet data network (PDN) or the Internet) higher than the EPC20 via the EPC20 and any of the eNBs. May be good. For example, the MEC server 10 may provide a dynamic map for a boundary area covered by a plurality of cells managed by the MEC server 10, and the cloud server may provide a dynamic map for a wider area.

<Outline of processing by MEC server>
As described above, the MEC server 10 provides a dynamic map (quasi-static information, quasi-dynamic information, dynamic information, etc.) to the vehicle traveling in the cell of each connected eNB, and is also dynamic. It is necessary to acquire point cloud data from each vehicle in order to update the map. Since the point cloud data has a large data size, if the point cloud data is transmitted from a large number of vehicles at the same time, the network load may increase. In addition, when point cloud data is transmitted from a vehicle in a cell with few free communication resources (that is, communication resources are tight), the communication resources are further tight and the network load is locally large. Can be.

Therefore, the MEC server 10 of the present embodiment appropriately determines one or more vehicles for transmitting point cloud data to the MEC server 10 based on the communication status in a plurality of cells to be managed, and points to the determined vehicle. Request the transmission of point cloud data.

Specifically, the MEC server 10 acquires communication status information indicating the communication status in each of the plurality of managed cells. As described later with reference to FIG. 10, the communication status information includes, for example, information indicating the usage status of communication resources (radio resources) in each cell, information on vehicles communicating in each cell, and throughput for each vehicle. Information indicating communication quality such as is included. The RNIS (Radio Network Information Services) function of the MEC server 10 is used to acquire the communication status information. RNIS is a service for acquiring network-related information such as communication quality in mobile networks, which is defined in the MEC standard specifications that are being standardized by ETSI. From the acquired communication status information, the MEC server 10 generates heat map information regarding the usage status of the communication resource, which is associated with the plurality of cells to be managed and the usage status of the communication resource in each cell.

Here, FIG. 3 is a diagram showing an example of heat map information generated by the MEC server 10. In FIG. 3, each cell is shown as a hexagonal cell as a simple example, but this is not the case. In this example, the MEC server 10 manages seven cells of cells # 1 to # 7, and shows the percentage of communication resources (communication band in this embodiment) being used as the usage status of communication resources. The usage rate B _r is used. Specifically, the usage rate B _r is defined as the ratio of the communication band B _{s in} use to the total communication band B _{a in the corresponding cell (Br} = B _s / B _a). As shown in FIG. 3, the MEC server 10 generates heat map information in which cells # 1 to # 7 and communication resource usage rates B _{r1 to} B _{r7 in each cell are associated with each other.}

The MEC server 10 is one or more vehicles that transmit point cloud data used for updating the dynamic map in the MEC server 10 among the vehicles traveling in a plurality of managed cells (cells # 1 to # 7). Is determined based on the generated heat map information. Further, the MEC server 10 requests the determined one or more vehicles to transmit the point cloud data to the MEC server 10. Specifically, MEC server 10 than vehicle running in the cell usage rate B _r higher communication resources (communication band), with priority vehicles traveling the utilization in low cell, point group Determine which vehicle will send the data. This is equivalent to determining the vehicle that transmits the point cloud data by giving priority to the vehicle traveling in the cell with many free communication resources over the vehicle traveling in the cell with few free communication resources. Is.

By the above-mentioned processing, the MEC server 10 makes effective use of the free communication resources while avoiding requesting the vehicle traveling in the cell having a small margin of communication resources to transmit the point cloud data. Communication for acquiring point cloud data from the vehicle becomes possible. As a result, it is possible to prevent the communication resources from becoming tight due to the communication between the vehicle and the MEC server 10 in some cells and increasing the network load. Therefore, it is possible to level the network load associated with the communication between the MEC server 10 that provides the dynamic map and each vehicle between cells (between eNBs).

Each MEC server 10 can communicate with other MEC servers and can share heat map information with other MEC servers. For example, in FIG. 1, the MEC server 10a can share heat map information with a nearby MEC server 10b. In that case, the MEC server 10a may determine one or more vehicles to transmit the point cloud data based on the heat map information generated by the MEC server 10a and the heat map information generated by the MEC server 10b. This makes it possible to achieve network load leveling over a wider geographical area.

Hereinafter, a specific example of the configuration and operation of the MEC server for realizing the above-mentioned processing, and a specific example of communication performed between the MEC server and each vehicle will be described.

<MEC server configuration>
FIG. 4 is a block diagram showing a hardware configuration example of the MEC server 10 according to the present embodiment. The MEC server 10 has a CPU 41, a ROM 42, a RAM 43, an external storage device 44 (HDD or the like), and a communication device 45 (communication interface).

In the MEC server 10, for example, a program stored in any one of the ROM 42, the RAM 43, and the external storage device 44, which realizes each function of the MEC server 10, is executed by the CPU 41. The CPU 41 may be replaced by one or more processors such as an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), and a DSP (digital signal processor).

Under the control of the CPU 41, the communication device 45 transfers (receives and transmits) packets transmitted between the node in the EPC 20 and each eNB connected to the MEC server 10, and communicates with each eNB (reception and transmission). Communication with the vehicle via each eNB) can be performed. Further, the communication device 45 can communicate with another adjacent MEC server under the control of the CPU 41. The MEC server 10 may have a plurality of communication devices 45 having different connection destinations.

The MEC server 10 may be provided with dedicated hardware for executing each function, or a part of the MEC server 10 may be executed by the hardware and the other part may be executed by a computer running the program. Also, all functions may be performed by a computer and a program.

FIG. 5 is a block diagram showing a functional configuration example of the MEC server 10 according to the present embodiment. Each function of the MEC server 10 is a logical function realized by the hardware of FIG. 4, for example, and can be realized by the CPU 41 executing a program stored in the ROM 42 or the like. In the present embodiment, the MEC server 10 has a communication information acquisition unit 51, a communication information collection unit 52, a communication information management unit 53, a communication information providing unit 54, and a dynamic map application (DMAP) 55.

The communication information acquisition unit 51 has a function of analyzing the contents of the packet transmitted between each eNB and the EPC 20. The communication information acquisition unit 51 has an RNIS function for acquiring network-related information such as communication quality in a mobile network based on the analysis result of such a packet, and the API of the RNIS function is transmitted to the communication information collection unit 52. offer. The communication information acquisition unit 51 acquires communication status information indicating the communication status in each of the plurality of cells (managed) corresponding to the plurality of eNBs connected to the MEC server 10 by this RNIS function.

The communication information collection unit 52 periodically collects communication status information using the communication information acquisition unit 51 (RNIS function), and transmits the collected communication status information to the communication information management unit 53. Each time the communication information management unit 53 receives the communication status information, the communication information management unit 53 manages the heat map information by generating the heat map information as described above from the communication status information and storing the heat map information in the RAM 43 or the external storage device 44. .. The communication information providing unit 54 periodically acquires the heat map information managed by the communication information management unit 53 and provides it to the DMAP 55.

DMAP 55 is an application for providing a dynamic map to a vehicle traveling in a plurality of managed cells. In the present embodiment, not only the dynamic map (for example, point cloud data, quasi-static information, quasi-dynamic information and dynamic information) is provided to the vehicle's automatic driving system, but also the information is acquired by the vehicle's automatic driving system. Obtain point cloud data from the vehicle. Specifically, the DMAP 55 is used for updating the dynamic map on the MEC server 10 among the vehicles traveling in the plurality of managed cells based on the heat map information provided by the communication information providing unit 54. Determine one or more vehicles to transmit point cloud data. Further, the DMAP 55 requests the determined one or more vehicles to transmit the point cloud data to the MEC server 10.

<Specific processing procedure of MEC server>
Next, a specific processing procedure executed by the MEC server 10 will be described using the network configuration shown in FIG. 6 as an example. In the example of FIG. 6, eNB # 1 and eNB # 2 are connected to the MEC server 10, and a group of vehicles travels on a road passing through adjacent cells # 1 and # 2 formed by eNB # 1 and eNB # 2. A and B are running. The vehicle group A is composed of three vehicles including the vehicle # 1 running in the cell # 1 (cell ID = 1) corresponding to the eNB # 1. The vehicle group B is composed of 12 vehicles including the vehicle # 2 running in the cell # 2 (cell ID = 2) corresponding to the eNB # 2. Each vehicle of the vehicle groups A and B is traveling in the direction indicated by the arrow in FIG.

In the following, in a state where the vehicle groups A and B do not transmit the point cloud data to the MEC server 10, the MEC server 10 bases the point cloud data on the vehicle # 1 included in the vehicle group A based on the heat map information. An example of requesting the transmission of is described. In the following description, the vehicle # 1 will be focused on among the vehicles included in the vehicle group A, but the same applies to the other vehicles included in the vehicle group A. Further, although the vehicle # 2 is focused on among the vehicles included in the vehicle group B, the same applies to the other vehicles included in the vehicle group B.

Here, FIG. 7 is a diagram showing an example of the usage status of the communication resource (communication band) before and after the start of transmission of the point cloud data from the vehicle # 1 in the cells # 1 and # 2 of FIG. Is. In FIG. 7, before the start of transmission of the point cloud data from the vehicle # 1, the cell # 2 to which the vehicle # 1 is moved has a free communication resource than the cell # 1 in which the vehicle # 1 is traveling. (Free bandwidth) is small (that is, the communication bandwidth usage rate _Br is high), indicating that communication resources are tight. In such a case, the DMAP 55 of the MEC server 10 requests the vehicle # 1 to transmit the point cloud data in the cell # 1 instead of the cell # 2. When the vehicle # 1 starts transmitting the point cloud data to the MEC server 10 in response to this request, the communication band B _s1 in use in the cell # 1 increases as shown in FIG. 7, and the communication band is used. The rate B _r1 (= B _s1 / B _a ) increases. In this way, DMAP55 is, by leveling the utilization B _r of the communication band in the cell # 1 and # 2 are leveled among the cells of the network load caused by communication between the vehicle and the MEC server 10 ..

In DMAP55, the cell # 2 to which the vehicle # 1 is moved has more free bandwidth than the cell # 1 in which the vehicle # 1 is traveling (that is, the communication band usage rate _Br is lower). In that case, the process opposite to the above-mentioned process is performed. That is, the DMAP 55 requests the vehicle # 1 to transmit the point cloud data in the cell # 2 instead of the cell # 1, so that the network load associated with the communication between the vehicle and the MEC server 10 is leveled between the cells. To become.

Next, FIGS. 8 and 9 are sequence diagrams of communication between the vehicle and the MEC server 10, and as described with reference to FIGS. 6 and 7, the vehicle # 1 traveling in the cell # 1 The processing procedure of the MEC server 10 when requesting the transmission of the point cloud data is shown.

As shown in FIG. 8, first, in S1, the vehicle # 1 in the cell # 1 performs wireless connection processing (attach processing) to the eNB # 1, and the vehicle # 2 in the cell # 2 wirelessly connects to the eNB # 2. Perform connection processing (attach processing). The wireless connection process to each eNB may be a handover process associated with the movement of the vehicle between cells. After that, in S2, the vehicle # 1 accesses the MEC server 10 and starts communication for acquiring the quasi-static information, the quasi-dynamic information, and the dynamic information included in the dynamic map from the DMAP 55. Further, the vehicle # 2 accesses the MEC server 10 and starts communication for acquiring the quasi-static information, the quasi-dynamic information, and the dynamic information included in the dynamic map from the DMAP 55. The quasi-static information, the quasi-dynamic information, and the dynamic information are information necessary for the automatic traveling of the vehicles # 1 and # 2. Therefore, the vehicles # 1 and # 2 are traveling while acquiring the quasi-static information, the quasi-dynamic information, and the dynamic information from the MEC server 10 according to the update frequency of each information (FIG. 2B). Run regularly.

Next, in S3, the communication information collecting unit 52 calls the communication information acquisition unit 51 (RNIS function) and requests the communication status information corresponding to the cells # 1 and # 2. In accordance with the request, in S4, the communication information acquisition unit 51 acquires the communication status information by the RNIS function, and returns a response including the acquired communication status information to the communication information collection unit 52. FIG. 10 is a diagram showing an example of communication status information acquired by the communication information acquisition unit 51. As shown in FIG. 10A, the communication status information includes information on vehicles communicating in each cell and information indicating communication quality (throughput) for each vehicle. Further, as shown in FIG. 10B, the communication status information further includes information indicating the usage status of the communication resource (radio resource) in each cell.

When the communication information collecting unit 52 receives the response from the communication information acquisition unit 51, the communication information collecting unit 52 transmits the communication status information included in the response to the communication information management unit 53 in S5. In S6, the communication information management unit 53 generates and stores the above-mentioned heat map information from the received communication status information in response to the reception of the communication status information. The above processes (81) of S3 to S6 are repeatedly executed at predetermined time intervals (for example, 5 second intervals). As a result, the heat map information is continuously updated at predetermined time intervals. The communication information management unit 53 is obtained from the communication status information, obtains a time average of the utilization B _r of the communication resources of each cell, may generate heat map information based on the average the time. This makes it possible to achieve network load leveling without being affected by the instantaneous increase in traffic.

Next, in S7, the communication information providing unit 54 requests the communication information management unit 53 for heat map information. In accordance with the request, in S8, the communication information management unit 53 returns a response including the stored heat map information to the communication information providing unit 54. Upon receiving the response, in S9, the communication information providing unit 54 notifies the DMAP 55 of the heat map information included in the response.

In S10, the DMAP 55 determines one or more vehicles to transmit the point cloud data to the MEC server 10 each time the notification of the heat map information is received. For example, in DMAP55, among cells # 1 and cell # 2, in the cell (cell # 1 in this example) in _{which the communication resource usage rate B r is low, the usage rate B r} is the threshold value B _th (for example, 0.7). ) Is not exceeded ( _Br ≤ B _th ), the vehicle # 1 traveling in the cell # 1 is requested to transmit the point cloud data to the MEC server 10. When the usage rate B _r1 exceeds the predetermined threshold value B _th (B _r1 > B _th ), the DMAP 55 points to the vehicle # 1 traveling in the cell # 1 to the MEC server 10. Does not require transmission of point cloud data.

Further, in S10, the DMAP 55 predicts the staying time of each vehicle in the cells # 1 and # 2, and when the staying time becomes long, the vehicle is prioritized and determined as the vehicle for transmitting the point cloud data, and the point cloud is determined. You may request the transmission of data. In this case, the DMAP 55 identifies and identifies the position and traveling direction of each vehicle in cells # 1 and # 2 based on, for example, quasi-static information, quasi-dynamic information, and dynamic information corresponding to each vehicle. Predict the staying time of each vehicle in the cell based on the position and the direction of travel. Thereby, it is possible to improve the temporal utilization efficiency of the communication resource used for the communication between the vehicle and the MEC server 10 in one cell.

For example, in the example of FIG. 11A _{, in cell # 1 where the communication resource usage rate B r1} is equal to or less than the threshold value B _th , based on the positions and traveling directions of vehicles # 11 and # 12, the communication resource usage rate B r1 is higher than that of vehicle # 12. It is predicted that vehicle # 11 will stay longer. Therefore, the DMAP 55 may request the vehicle # 11 to transmit the point cloud data in the cell # 1. The example of FIG. 11B shows a case where the communication resource usage rate B _r2 becomes equal to or less than the threshold value B _{th after the vehicles # 11 and # 12 move to the cell # 2.} In this case, the DMAP 55 may request the vehicle # 11 to transmit the point cloud data in the cell # 2 as a result of predicting the staying time of the vehicles # 11 and # 12 in the cell # 2.

Further, in S10, the vehicle for transmitting the point cloud data may be determined based on the communication quality (throughput) included in the communication status information. For example, a vehicle having a high throughput may be prioritized and determined as a vehicle for transmitting point cloud data. As a result, the point cloud data can be transmitted from the vehicle to the MEC server 10 in a shorter time, and the usage time of the communication resource for the transmission can be shortened.

The above processes (82) of S7 to S10 are repeatedly executed at predetermined time intervals (for example, 10 second intervals). According to the result of the above determination in S10, in S11 the DMAP 55 requests the vehicle # 1 to transmit the point cloud data. The DMAP 55 may be designated as data to be transmitted even for data other than the point cloud data. Further, when the DMAP 55 determines as a result of the determination in S10 that a plurality of vehicles including the vehicle # 1 included in the vehicle group A are vehicles for transmitting the point cloud data, the DMAP 55 simultaneously refers to the plurality of vehicles. You may send a request.

In response to the transmission request in S11, the vehicle # 1 starts transmitting the point cloud data to the MEC server 10 in S12. As a result, the vehicle # 1 receives the quasi-static information, the quasi-dynamic information, and the dynamic information (specific information) from the MEC server 10 at predetermined time intervals among the information constituting the dynamic map, and in S11. The point cloud data is transmitted to the MEC server 10 in response to the transmission request.

Next, FIG. 9 shows a processing procedure of the MEC server 10 when the vehicle # 1 moves from the cell # 1 to the cell # 2 in S21 after the processing shown in FIG. In this case, in S22, the vehicle # 1 performs a handover process for switching the connection destination from the eNB # 1 to the eNB # 2. When the handover process is completed, the vehicle # 1 communicates with the MEC server 10 via the eNB # 2 (that is, receives quasi-static information, quasi-dynamic information and dynamic information, and transmits point cloud data). Will continue. Meanwhile, in the MEC server 10, the above-mentioned processes 81 and 82 are periodically repeated, respectively.

In the determination of the vehicle for transmitting the point cloud data to the MEC server 10 in the process 82 (S10), in the DMAP 55, the communication resource usage rate B _r2 in the cell # 2 exceeds the threshold B _{th (B r2} > B). _th ), vehicle # 1 will be excluded from the vehicle transmitting the point cloud data. According to this decision, in S23, the DMAP 55 requests the vehicle # 1 to stop transmitting the point cloud data. Note that the DMAP 55 may be able to specify data other than the point cloud data as data for which transmission should be stopped.

In response to the stop request in S23, vehicle # 1 stops transmitting point cloud data to the MEC server 10 in S24. As a result, vehicle # 1 is in a state of receiving quasi-static information, quasi-dynamic information, and dynamic information (specific information) from the MEC server 10 at predetermined time intervals without transmitting point cloud data. ..

As described above, in the present embodiment, the MEC server 10 generates heat map information regarding the usage status of communication resources from the communication status information obtained by using the RNIS function. Further, the MEC server 10 transmits point cloud data to the MEC server 10 among vehicles traveling in a plurality of cells managed by the MEC server 10 based on the generated heat map information. Determine the vehicle and request the transmission of point cloud data. This makes it possible to level the network load associated with communication between the MEC server 10 that provides the dynamic map and the vehicle. In order to generate heat map information by the MEC server 10, it is not necessary to introduce additional functions such as a communication quality information transmission function into the automatic driving system provided in the vehicle, which reduces the labor of kitting the automatic driving system. can.

The MEC server (server device) according to the present embodiment can be realized by a computer program for making a computer function as a MEC server. The computer program is stored in a computer-readable storage medium and can be distributed, or can be distributed via a network.

10 (10a, 10b): MEC server (server device), 20: core network 41: CPU, 42: ROM, 43: RAM, 44: external storage device, 45: communication device 51: communication information acquisition unit (RNIS function) , 52: Communication information collection unit, 53: Communication information management department, 54: Communication information provision department, 55: Dynamic map application (DMAP)

Claims (16)

A server device connected between multiple base stations and a core network.
An acquisition means for acquiring communication status information indicating the communication status in each of the plurality of cells corresponding to the plurality of base stations, and
A generation means for generating heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the communication status information acquired by the acquisition means.
Among the vehicles traveling in the plurality of cells, one or more vehicles that transmit data used for updating the dynamic map provided for automatic traveling of the vehicles in the plurality of cells are generated by the generation means. A requesting means for requesting the one or more vehicles determined based on the heat map information generated by the above to transmit the data to the server device.
A server device characterized by comprising. A server device connected between multiple base stations and a core network.
An acquisition means for acquiring communication status information indicating the communication status in each of the plurality of cells corresponding to the plurality of base stations, and
A generation means for generating heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the communication status information acquired by the acquisition means.
Among the vehicles traveling in the plurality of cells, one or more vehicles that transmit data used for updating the dynamic map provided for automatic traveling of the vehicles in the plurality of cells are generated by the generation means. A requesting means for requesting a vehicle other than the determined vehicle to stop transmitting the data to the server device, which is determined based on the heat map information generated by the server device.
A server device characterized by comprising. The requesting means is characterized in that a vehicle traveling in a cell having a large number of free communication resources is prioritized over a vehicle traveling in a cell having a small number of free communication resources to determine a vehicle for transmitting the data. The server device according to claim 1 or 2. The requesting means transmits the data by giving priority to a vehicle traveling in the cell having a low usage rate over a vehicle traveling in a cell having a high usage rate indicating the percentage of the communication resource in use. The server device according to any one of claims 1 to 3, wherein the vehicle is determined. The requesting means does not determine a vehicle traveling in a cell in which the usage rate indicating the percentage of the communication resource in use exceeds a predetermined threshold value as a vehicle for transmitting the data, and the usage rate is the said. The server device according to any one of claims 1 to 4, wherein among the vehicles traveling in the cell that does not exceed the threshold value, the vehicle that transmits the data to the server device is determined. .. If the usage rate of the second cell to which the first vehicle is moved is higher than that of the first cell in which the first vehicle is traveling among the plurality of cells, the requesting means is said to be the first. The server device according to claim 4 or 5, wherein the determination is made for the first vehicle so that the data is transmitted in the first cell instead of the second cell. If the usage rate of the second cell to which the first vehicle is moved is lower than that of the first cell in which the first vehicle is traveling among the plurality of cells, the requesting means is said to be the first. The server device according to claim 4 or 5, wherein the determination is made for the first vehicle so that the data is transmitted in the second cell instead of the first cell. For each of the plurality of cells, a prediction means for specifying the position and traveling direction of each vehicle in the cell and predicting the staying time of each vehicle in the cell based on the specified position and traveling direction is further provided. ,
Claims 1 to 7, wherein the requesting means determines, for each of the plurality of cells, a vehicle having a longer staying time in the cell as a vehicle for transmitting the data. The server device according to any one item. The server device transmits, among the information constituting the dynamic map, specific information regarding the road condition around the vehicle to each vehicle in the plurality of cells at predetermined time intervals, and the server. The server device according to any one of claims 1 to 8, wherein the data transmitted from each vehicle is received in response to a transmission request by the device. The specific information includes quasi-static information and quasi-dynamic information including at least information on traffic regulations and traffic congestion in the vicinity, and dynamic information including at least information on vehicles, pedestrians and signals in the vicinity. 9. The server device according to claim 9. The acquisition means acquires the communication status information at predetermined time intervals, and obtains the communication status information.
The server device according to any one of claims 1 to 10, wherein the generation means generates the heat map information each time the communication status information is acquired. The generation means generates the heat map information based on the time average of the usage rate indicating the percentage of communication resources in use in each cell, which is obtained from the communication status information acquired by the acquisition means. The server device according to any one of claims 1 to 11. The server device can communicate with other adjacent server devices and can communicate with each other.
The generation means shares the generated heat map information and the heat map information generated in the other server device with the other server device.
The requesting means determines one or more vehicles to transmit the data based on the heat map information generated by the generating means and the heat map information generated by the other server device. The server device according to any one of claims 1 to 12. It is a control method for server devices connected between multiple base stations and the core network.
An acquisition step of acquiring communication status information indicating the communication status in each of the plurality of cells corresponding to the plurality of base stations, and
A generation step of generating heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the communication status information acquired in the acquisition step.
Among the vehicles traveling in the plurality of cells, one or more vehicles that transmit data used for updating the dynamic map provided for automatic traveling of the vehicles in the plurality of cells are generated in the generation step. A requesting process of requesting the one or more vehicles determined based on the heat map information generated in the above to transmit the data to the server device, and
A method of controlling a server device, which comprises. It is a control method for server devices connected between multiple base stations and the core network.
An acquisition step of acquiring communication status information indicating the communication status in each of the plurality of cells corresponding to the plurality of base stations, and
A generation step of generating heat map information in which the plurality of cells and the usage status of communication resources in each cell are associated with each other from the communication status information acquired in the acquisition step.
Among the vehicles traveling in the plurality of cells, one or more vehicles that transmit data used for updating the dynamic map provided for automatic driving of the vehicles in the plurality of cells are generated in the generation step. A requesting process of determining based on the heat map information generated in the above and requesting a vehicle other than the determined vehicle to stop transmitting the data to the server device.
A method of controlling a server device, which comprises. A program for causing a computer of the server device to execute each step of the control method of the server device according to claim 14 or 15.

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