JP2019087847A - Server device, control method therefor, and program - Google Patents

Abstract

To provide a technique capable of levelling a network load involved in communication between a server device providing a dynamic map by using edge computing and a vehicle.SOLUTION: An MEC server 10 generates heat map information on a use situation of communication resources from communication situation information obtained by using an RNIS function (S3-S6). The MEC server 10 determines one or more vehicles that transmit point group data to the MEC server 10 from vehicles running inside a plurality of cells managed by the MEC server 10 on the basis of the generated heat map information (S7-S10) and requests transmission of the point group data (S11).SELECTED DRAWING: Figure 8

Description

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

  A dynamic map (high-precision three-dimensional map) has been studied as an elemental technology for realizing a level of automatic driving that does not require a driver's operation in a vehicle such as a passenger car. In addition, in order to provide dynamic maps to vehicles in motion, studies are underway to use multi-access edge computing (MEC), which is being standardized by the ETSI (European Telecommunications Standards Institute). ing. When using MEC, the server apparatus (MEC server) distributed near the edge of the mobile network (for example, between the base station and the core network), in the cell of the base station connected to the server apparatus Provide a dynamic map of the narrow area to This is expected to reduce, for example, the network load involved in the communication between the cloud server that provides a wider dynamic map and the vehicle.

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

“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 prior art, if a large number of vehicles communicate with the MEC server simultaneously in the area where the communication success rate is high, the load on the network may increase locally due to the increased traffic. As a result, congestion and communication delays occur in the network, which can lead to the occurrence of communication errors in the communication between the vehicle and the MEC server.

  The present invention has been made in view of the above problems. An object of the present invention is to provide a technology capable of leveling the network load involved in communication between a server and a vehicle that provides a dynamic map using edge computing.

  A server apparatus according to an aspect of the present invention is connected between a plurality of base stations and a core network, and provides a dynamic map for automatic traveling of a vehicle in a plurality of cells corresponding to the plurality of base stations. A server apparatus, acquisition means for acquiring communication state information indicating communication states in each of the plurality of cells, and communication in each of the plurality of cells from the communication state information acquired by the acquisition means The generation unit for generating heat map information correlated with the use status of resources, and three-dimensional coordinates of an object around each vehicle among vehicles traveling in the plurality of cells, and the server device At least one vehicle for transmitting the point cloud data used for updating the dynamic map, based on the heat map information generated by There determined, the determined said one or more vehicles, characterized in that it and a request means for requesting transmission of the point group data to the server device.

  According to the present invention, it is possible to equalize the network load involved in communication between a server and a vehicle that provides a dynamic map using edge computing.

FIG. 1 shows a network configuration including an MEC server according to an embodiment. The figure which shows the example of a structure and the content of the dynamic map which concerns on one Embodiment. The conceptual diagram which shows the example of the heat map information produced | generated in the MEC server which concerns on one Embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of an MEC server according to an embodiment. FIG. 2 is a block diagram showing an example of the functional configuration of an MEC server according to an embodiment. The figure which shows an example of the condition in the cell of each eNB which concerns on one Embodiment. The figure which shows the example of the use condition of the communication resource (communication band) which concerns on one Embodiment. FIG. 5 is a sequence diagram of communication between a vehicle and an MEC server according to one embodiment. FIG. 5 is a sequence diagram of communication between a vehicle and an MEC server according to one embodiment. The figure which shows the example of the communication condition information which concerns on one Embodiment. The figure which shows an example of the condition 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 the following drawings, components 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 fifth generation (5G) mobile network that is being standardized in the Third Generation Partnership Project (3GPP).

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

  The MEC server 10 is a server device for edge computing (MEC in the present embodiment). As shown in FIG. 1, the MEC server 10 (each of the MEC servers 10 a and 10 b) is connected between a plurality of base stations (eNBs) and a core network (EPC) 20. The MEC server 10 manages a plurality of cells (corresponding to the plurality of eNBs), which are communication ranges of the plurality of connected eNBs, for automatically traveling a vehicle in the plurality of cells. Provide a dynamic map of In addition, each vehicle which travels the inside of a cell is equipped with the automatic travel system for performing automatic travel using a dynamic map.

<Dynamic map>
FIG. 2A is a view showing an example of the configuration of the dynamic map, and FIG. 2B is a view showing an example of the data of each item constituting the dynamic map in detail. 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), semi-static information, semi-dynamic information, and dynamic information.

  The point cloud data included in the dynamic map is data indicating the three-dimensional coordinates of the object (showing the three-dimensional coordinates of 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, point cloud data acquired by the vehicle provided (uploaded) from (the automatic traveling system of) the traveling vehicle may be used. In this embodiment, the MEC server 10 requests the vehicle traveling in the cell managed by the MEC server 10 to transmit point cloud data used for updating the dynamic map held for provision to the vehicle. Do. The automatic travel system of the traveling vehicle acquires point cloud data on an object around the vehicle by measurement using a laser scanner, and also acquires the acquired point cloud data in response to a transmission request from the MEC server 10. Send to the MEC server 10

  The semi-static information, the semi-dynamic information and the dynamic information included in the dynamic map are an example of specific information on the road condition around the vehicle, and are updated with a short update frequency in hours, minutes or seconds. As shown in FIG. 2 (B), the semi-static information and the semi-dynamic information include at least information on traffic regulation and traffic congestion around the vehicle, and the dynamic information includes vehicles, pedestrians and the like around the vehicle. It contains at least the information of the signal. Quasi-static information, quasi-dynamic information and dynamic information need to be continuously provided to the vehicle at relatively short time intervals while the vehicle is traveling, in order to realize automatic traveling.

  The MEC server 10 may individually provide the data of each item shown in FIG. 2 to the vehicle, or may provide the data of all items together to the vehicle. Also, at least a portion of the dynamic map is provided to the vehicle from the cloud server disposed in the external network (for example, packet data network (PDN) or the Internet) higher than the EPC 20 via the EPC 20 and any eNB. It is also good. For example, the MEC server 10 may provide a dynamic map of a border area covered by a plurality of cells managed by itself, and a cloud server may provide a dynamic map of a wider area.

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

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

  Specifically, the MEC server 10 acquires communication status information indicating the communication status in each of the plurality of cells to be managed. As the communication status information, as will be described later with reference to FIG. 10, for example, information indicating the usage status of communication resources (radio resources) in each cell, information regarding vehicles communicating in each cell, and throughput for each vehicle And other information indicating communication quality. The radio network information service (RNIS) 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 a mobile network, which has been formulated in MEC standard specifications which are being standardized in ETSI. The MEC server 10 generates, from the acquired communication status information, heat map information on the usage status of the communication resource, in which the plurality of cells to be managed are associated with the usage status of the communication resource in each cell.

Here, FIG. 3 is a diagram showing an example of heat map information generated in the MEC server 10. In addition, although each cell is shown by a hexagonal cell as a simple example in FIG. 3, it is not this limitation. In this example, the MEC server 10 manages seven cells of cells # 1 to # 7, and indicates the ratio in use of communication resources (communication band in the present embodiment) as the use status of communication resources. The utilization rate B _r is used. Specifically, the utilization rate B _r is defined as the ratio of the in-use communication band B _{s to} the total communication band B _a in the corresponding cell (B _r = B _s / B _a ). MEC server 10, as shown in FIG. 3, the cell # 1 to # 7, to produce a heat map information associating usage B _r1 .about.B _r7 of communication resources in each cell.

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 vehicles traveling in a plurality of cells (cells # 1 to # 7) to be managed. Are determined based on the generated heat map information. Furthermore, the MEC server 10 requests the determined one or more vehicles to transmit 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 Decide which vehicle will transmit data. This is equivalent to determining a vehicle that transmits point cloud data by prioritizing a vehicle traveling in a cell with many vacant communication resources over a vehicle traveling in a cell with few vacant communication resources. It is.

  According to the processing as described above, the MEC server 10 effectively uses the idle communication resource while avoiding requesting the transmission of the point cloud data to the vehicle traveling in the cell with a small margin of the communication resource. Communication can be performed to obtain point cloud data from the vehicle. As a result, communication resources may be strained due to communication between vehicles in some cells and the MEC server 10, and network load may be prevented from increasing. Therefore, it becomes possible to equalize the network load accompanying communication between MEC server 10 which provides a 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 the nearby MEC server 10b. In that case, the MEC server 10a may determine one or more vehicles that transmit point cloud data, based on the heat map information generated by itself and the heat map information generated in the MEC server 10b. This makes it possible to achieve network load balancing over a wider geographical area.

  In the following, specific examples of the configuration and operation of the MEC server for realizing the processing as described above, and specific examples of communication performed between the MEC server and each vehicle will be described.

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

  In the MEC server 10, for example, a program stored in any of the ROM 42, the RAM 43, and the external storage device 44 for executing the functions 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).

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

  The MEC server 10 may include dedicated hardware for executing each function, or may execute a part of the hardware and a computer that operates a program to execute other parts. Also, all functions may be performed by a computer and a program.

  FIG. 5 is a block diagram showing an example of the functional configuration of the MEC server 10 according to the present embodiment. Each function of the MEC server 10 is, for example, a logical function realized by the hardware in FIG. 4 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 includes a communication information acquisition unit 51, a communication information collection unit 52, a communication information management unit 53, a communication information provision unit 54, and a dynamic map application (DMAP) 55.

  The communication information acquisition unit 51 has a function of analyzing the contents of packets transmitted between each eNB and the EPC 20. The communication information acquisition unit 51 has an RNIS function of acquiring network related information such as communication quality in the mobile network based on the analysis result of such a packet, and transmits the API of the RNIS function to the communication information collection unit 52. provide. The communication information acquisition unit 51 acquires communication status information indicating the communication status in each of a plurality of (managed) cells corresponding to a plurality of eNBs connected to the MEC server 10 using 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. The communication information management unit 53 manages the heat map information by generating the heat map information as described above from the communication state information each time the communication state information is received, and storing the heat map information in the RAM 43 or the external storage device 44. . The communication information provider 54 periodically acquires the heat map information managed by the communication information manager 53 and provides the DMAP 55 with the heat map information.

  The DMAP 55 is an application for providing a dynamic map to a vehicle traveling in a plurality of cells to be managed. In this embodiment, not only the provision of a dynamic map (for example, point cloud data, quasi-static information, quasi-dynamic information and dynamic information) to an automatic travel system of a vehicle, but also acquisition by the automatic travel system of a vehicle Point cloud data is acquired from the vehicle. Specifically, the DMAP 55 is used to update the dynamic map in the MEC server 10 among the vehicles traveling in the plurality of cells to be managed based on the heat map information provided from the communication information provider 54. One or more vehicles which transmit point cloud data are determined based on the generated heat map information. Further, the DMAP 55 requests the determined one or more vehicles to transmit 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 by taking 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 road passing through adjacent cells # 1 and # 2 formed by eNB # 1 and eNB # 2 is a vehicle group A and B are traveling. The vehicle group A includes three vehicles including the vehicle # 1 traveling in the cell # 1 (cell ID = 1) corresponding to the eNB # 1. The vehicle group B includes 12 vehicles including the vehicle # 2 traveling in the cell # 2 (cell ID = 2) corresponding to the eNB # 2. In addition, each vehicle of vehicle group A and B is drive | working toward the direction shown by the arrow in FIG.

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

Here, FIG. 7 is a diagram showing an example of the use status of communication resources (communication band) before and after the start of transmission of point group data from the vehicle # 1 in the cells # 1 and # 2 of FIG. It is. In FIG. 7, before the start of transmission of point cloud data from vehicle # 1, communication resource of cell # 2 to which vehicle # 1 is moving is an empty communication resource than cell # 1 in which vehicle # 1 is traveling. The (available bandwidth) is small (ie, the communication bandwidth usage rate _Br is high), which indicates that communication resources are under pressure. In such a case, the DMAP 55 of the MEC server 10 requests the vehicle # 1 to transmit point cloud data not in the cell # 2 but in the cell # 1. When vehicle # 1 starts transmission of point cloud data to MEC server 10 in response to this request, communication band B _s1 in use in 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 .

Incidentally, DMAP55, rather than cell # 1 of the vehicle # 1 is traveling, towards the cell # 2 as the destination of the vehicle # 1, free bandwidth is large (i.e., low usage B _r of the communication band) In this case, the process opposite to the above process is performed. That is, by requesting the vehicle # 1 to transmit the point cloud data in the cell # 2 instead of the cell # 1, the DMAP 55 equalizes the network load involved in the communication between the vehicle and the MEC server 10 between the cells. Turn

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

  As shown in FIG. 8, first, in S1, the vehicle # 1 in the cell # 1 performs a radio connection process (attach process) on the eNB # 1, and the vehicle # 2 in the cell # 2 wirelessly to the eNB # 2 Perform connection processing (attach processing). In addition, the wireless connection process to each eNB may be a handover process accompanying the movement of a vehicle between cells. Thereafter, 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. In addition, 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. For this reason, vehicles # 1 and # 2 are traveling while acquiring the quasi-static information, quasi-dynamic information and dynamic information from MEC server 10 according to the update frequency of each information (FIG. 2 (B)). Run regularly.

  Next, in S3, the communication information collection unit 52 calls the communication information acquisition unit 51 (RNIS function) to request communication status information corresponding to the cell # 1 and the cell # 2. According to the request, in S4, the communication information acquisition unit 51 acquires 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 illustrating an example of communication status information acquired by the communication information acquisition unit 51. The communication status information includes, as shown in FIG. 10A, information on vehicles communicating in each cell, and information indicating communication quality (throughput) for each vehicle. Further, as shown in FIG. 10 (B), the communication status information further includes information indicating the usage status of the communication resource (radio resource) in each cell.

When receiving the response from the communication information acquisition unit 51, the communication information collection 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-described processes (S <b> 3 to S <b> 6) (81) are repeatedly performed at predetermined time intervals (e.g., five seconds). Thus, the heat map information continues to be 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 instantaneous traffic increase.

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

In S10, the DMAP 55 determines one or more vehicles that transmit point cloud data to the MEC server 10 each time the heat map information notification is received. For example, DMAP55 among the cell # 1 and cell # 2 (in this example, cell # 1) cell usage rate B _r is low communication resources in utilization B _r is the threshold B _th (e.g., 0.7 If not (B _r ≦ B _th ), the vehicle # 1 traveling in the cell # 1 is requested to transmit point cloud data to the MEC server 10. In the DMAP 55, when the usage rate B _r1 exceeds the predetermined threshold B _th (B _r1 > B _th ), the vehicle # 1 traveling in the cell # 1 is a point to the MEC server 10 Does not require transmission of group data.

  Further, in S10, the DMAP 55 predicts the staying time of each vehicle in the cells # 1 and # 2, and prioritizes the vehicle when the staying time is long, and determines it as a vehicle that transmits point cloud data, It may request transmission of data. In this case, the DMAP 55 identifies and identifies the position and the traveling direction of each vehicle in the cells # 1 and # 2 based on, for example, quasi-static information, quasi-dynamic information, and dynamic information corresponding to each vehicle. The residence time of each vehicle in the cell is predicted based on the position and the traveling direction. Thereby, it is possible to improve the temporal use efficiency of the communication resource used in the communication between the vehicle and the MEC server 10 in one cell.

For example, in the example of FIG. 11A, in the cell # 1 in which the usage rate _Br1 of the communication resource is equal to or less than the threshold B _th , based on the positions and the traveling directions of the vehicles # 11 and # 12, It is predicted that the staying time will be longer for the vehicle # 11. Therefore, the DMAP 55 can request the vehicle # 11 to transmit point cloud data in the cell # 1. The example of FIG. 11B shows the case where the usage rate _Br2 of the communication resource becomes equal to or less than the threshold 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 point cloud data in the cell # 2 as a result of the prediction of the staying times of the vehicles # 11 and # 12 in the cell # 2.

  Moreover, in S10, the vehicle which transmits point cloud data may be determined based on the communication quality (throughput) included in the communication status information. For example, a vehicle having high throughput may be prioritized to be determined as a vehicle that transmits point cloud data. Thereby, the point cloud data can be transmitted from the vehicle to the MEC server 10 in a shorter time, and it becomes possible to shorten the usage time of the communication resource for the transmission.

  The above-described processes (S7 to S10) (82) are repeatedly performed at predetermined time intervals (for example, 10 seconds). In accordance with the result of the above-described determination in S10, DMAP 55 requests vehicle # 1 to transmit point cloud data in S11. The DMAP 55 may be able to designate data other than point cloud data as data to be transmitted. Further, when the DMAP 55 determines, as a result of the determination in S10, a plurality of vehicles including the vehicle # 1 included in the vehicle group A as a vehicle transmitting point cloud data, the DMAP 55 simultaneously operates on the plurality of vehicles. A request may be sent.

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

  Next, FIG. 9 shows the 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 (ie, receives quasi-static information, quasi-dynamic information and dynamic information, and transmits point cloud data) with the MEC server 10 via the eNB # 2. It will continue. Meanwhile, in the MEC server 10, the processes 81 and 82 described above are periodically repeated.

In process 82 (S10), the determination of the vehicle for transmitting the point cloud data to the MEC server 10, DMAP55, because the utilization B _r2 of communication resources in the cell # 2 is higher than the threshold value B _th (B _r2> B _th ), vehicle # 1 will be excluded from vehicles transmitting point cloud data. According to this determination, at S23, the DMAP 55 requests the vehicle # 1 to stop the transmission of the point cloud data. 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, the vehicle # 1 stops transmission of point cloud data to the MEC server 10 in S24. Thus, vehicle # 1 is in a state of receiving quasi-static information, quasi-dynamic information, and dynamic information (specific information) from 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 on the usage status of the communication resource from the communication status information obtained using the RNIS function. Furthermore, the MEC server 10 transmits at least one point cloud data to the MEC server 10 among vehicles traveling in the plurality of cells to be managed by the MEC server 10 based on the generated heat map information. Determine the vehicle and request transmission of point cloud data. This makes it possible to equalize the network load involved in the communication between the MEC server 10 providing the dynamic map and the vehicle. There is no need to introduce additional functions such as the transmission function of communication quality information into the automatic travel system equipped on the vehicle for the generation of heat map information by the MEC server 10, thus reducing the effort of kitting the automatic travel system it can.

  The MEC server (server apparatus) according to this embodiment can be realized by a computer program for causing a computer to function as the 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 apparatus) 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 unit, 54: communication information provision unit, 55: dynamic map application (DMAP)

Claims (15)

A server apparatus connected between a plurality of base stations and a core network and providing a dynamic map for automatic traveling of a vehicle in a plurality of cells corresponding to the plurality of base stations,
Acquisition means for acquiring communication status information indicating communication status in each of the plurality of cells;
Generation means for generating heat map information in which the plurality of cells are associated with the use state of communication resources in each cell from the communication state information acquired by the acquisition means;
One or more of the vehicles running in the plurality of cells, which indicate three-dimensional coordinates of an object around each vehicle, and transmit point cloud data used for updating the dynamic map in the server device Request means for determining a vehicle based on the heat map information generated by the generation means, and requesting the determined one or more vehicles to transmit the point cloud data to the server device;
A server apparatus comprising: The request means determines the point cloud data to be transmitted by giving priority to a vehicle traveling in a cell having many vacant communication resources over a vehicle traveling in a cell having few vacant communication resources. The server apparatus according to claim 1, characterized in that The request means transmits the point cloud data by prioritizing a vehicle traveling in a cell having a low usage rate over a vehicle traveling in a cell having a high usage rate indicating a ratio during use of the communication resource. The server apparatus according to claim 1 or 2, wherein the server apparatus is determined to be a vehicle that performs. The request means does not request transmission of the point cloud data to a vehicle traveling in a cell whose usage rate indicating the usage rate of the communication resource exceeds a predetermined threshold, and the usage rate is the threshold The server apparatus according to any one of claims 1 to 3, wherein transmission of the point cloud data to the server apparatus is requested to a vehicle traveling in a cell not exceeding. Among the plurality of cells, if the second cell, which is the moving destination of the first vehicle, has a higher utilization rate than the first cell among the plurality of cells, The server apparatus according to claim 3 or 4, wherein the first vehicle is requested to transmit the point cloud data not in two cells but in the first cell. If the second cell to which the first vehicle is to be moved has a lower utilization rate than the first cell in which the first vehicle is traveling among the plurality of cells, the request means may be configured to The server apparatus according to claim 3 or 4, wherein the first vehicle is requested to transmit the point cloud data not in one cell but in the second cell. For each of the plurality of cells, there is further provided prediction means for identifying the position and the traveling direction of each vehicle in the cell, and predicting the staying time of each vehicle in the cell based on the identified position and traveling direction. ,
The request means determines, for each of the plurality of cells, as a vehicle that transmits the point cloud data, prioritizing a vehicle whose stay time in the cell is long. The server apparatus according to any one of 6. Each vehicle in the plurality of cells is transmitted by the request unit while receiving specific information on the road condition around the vehicle among the information constituting the dynamic map from the server device at predetermined time intervals. The server apparatus according to any one of claims 1 to 7, wherein the point cloud data is transmitted to the server apparatus in response to a request. The server apparatus according to claim 8, wherein each vehicle in the plurality of cells transmits point cloud data acquired by measurement using a laser scanner to the server apparatus in response to the transmission request. The specific information includes semi-static information and semi-dynamic information including at least information on traffic control and traffic congestion in the vicinity, and dynamic information including at least information on vehicles, pedestrians, and signals in the vicinity. The server apparatus according to claim 8 or 9, characterized in that The acquisition means acquires the communication status information at predetermined time intervals,
The server apparatus according to any one of claims 1 to 10, wherein the generation unit generates the heat map information each time the communication status information is acquired. The generation means generates the heat map information on the basis of a time average of a usage rate indicating a ratio in use of communication resources in each cell, which is obtained from the communication status information acquired by the acquisition means. The server apparatus according to any one of claims 1 to 11. The server device can communicate with another adjacent server device,
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 request means determines one or more vehicles that transmit the point cloud data, based on the heat map information generated by the generation means and the heat map information generated by the other server device. The server apparatus according to any one of claims 1 to 12, wherein A control method of a server apparatus connected between a plurality of base stations and a core network and providing a dynamic map for automatic traveling of a vehicle in a plurality of cells corresponding to the plurality of base stations,
An acquisition step of acquiring communication status information indicating a communication status in each of the plurality of cells;
A generation step of generating heat map information in which the plurality of cells and the use status of the communication resource in each cell are associated from the communication state information acquired in the acquisition step;
One or more of the vehicles running in the plurality of cells, which indicate three-dimensional coordinates of an object around each vehicle, and transmit point cloud data used for updating the dynamic map in the server device A request step of determining a vehicle based on the heat map information generated in the generation step and requesting the determined one or more vehicles to transmit the point cloud data to the server device;
And controlling the server apparatus.   The program for making the computer of the said server apparatus perform each process of the control method of the server apparatus of Claim 14.

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