JP7052544B2 - Wireless resource allocation method and equipment, and computer program - Google Patents

Description

The present invention relates to radio resource allocation methods and devices, as well as computer programs.

A large number of roadside units are installed near intersections in order to perform wireless communication with mobile stations such as in-vehicle units. When multiple roadside units use the same radio resource, mutual interference of radio waves occurs.
Therefore, it is desired to allocate radio resources to a plurality of roadside machines so as to prevent interference as much as possible.

Non-Patent Documents 1 and 2 describe an algorithm of a radio resource allocation method suitable for a roadside machine of an ITS (Intelligent Transport Systems) radio.
In Patent Document 1, at least a part of the first radio resource is allocated to the first roadside machine installed in the first area adjacent to the boundary such as the prefectural border, and the second roadside machine is installed in the second area away from the boundary. Describes a radio resource allocation method for allocating a second radio resource different from the first radio resource.

Japanese Unexamined Patent Publication No. 2017-38214

Hirozumi Yamaguchi et al., "Wireless Mutual Interference Arbitration Algorithm Suitable for Operation Scenarios of Densely Installed ITS Roadside Machines", IPSJ Research Report. ITS, 2014-ITS-59 (28), 1-8, 2014-11-13 Hirozumi Yamaguchi et al., "Spatial Division Scheduling Technology for Radio Mutual Interference Arbitration of Dense Base Stations", IPSJ Journal, Vol. 55, No. 2, pp. 826-837, 2014

In the prior art document, the appropriate method for sequentially allocating radio resources to new roadside machines without changing the radio resources of existing roadside machines by using multiple types of algorithms such as VC algorithm and PSG algorithm together is described. Not expected.
In view of such conventional problems, it is an object of the present invention to provide an appropriate radio resource allocation method when the VC algorithm and the PSG algorithm are used in combination.

(1) The allocation method according to one aspect of the present invention is a method of allocating radio resources to the roadside unit of the ITS radio, and when the cell of the VC map contains only the position information of the newly installed roadside unit, the cell is described. The first step of performing VC allocation to apply the radio resources allocated to the new roadside machine to the new roadside machine, and when the VC map cell contains the position information of the new roadside machine and the position information of other roadside machines. For the newly installed roadside machine, the second step of performing PSG allocation for allocating radio resources by the PSG algorithm is included.

(7) The allocation device according to one aspect of the present invention is a device that allocates radio resources to the roadside unit of the ITS radio, and has a storage unit that stores a VC map created based on the VC algorithm and a newly installed roadside unit. It is provided with an information processing unit that determines whether the VC allocation or the PSG allocation defined below is applied to the newly installed roadside machine depending on whether or not the position information of the above is unique in the cell of the VC map.
VC allocation: Process of applying the radio resource of the cell of the VC map to the new roadside machine PSG allocation: Process of allocating the radio resource to the new roadside machine by the PSG algorithm

(8) The computer program according to one aspect of the present invention is a computer program for operating a computer as a device for allocating radio resources to a roadside unit of an ITS radio, and is newly installed in the computer and in a cell of a VC map. When only the position information of the roadside machine is included, the first step of performing VC allocation to apply the radio resource allocated to the cell to the new roadside machine, and the position information of the new roadside machine in the cell of the VC map. And the second step of performing PSG allocation for allocating radio resources based on the PSG algorithm for the newly installed roadside machine when the position information of the other roadside machine is included.

According to the present invention, when the VC algorithm and the PSG algorithm are used in combination, radio resources can be appropriately allocated.

It is a block diagram which shows the configuration example of a radio resource allocation device. It is explanatory drawing of the usage condition of a wireless resource and the installation condition of a roadside machine. It is explanatory drawing which shows an example of the processing content of the VC map generation part. It is explanatory drawing which shows an example of the allocation processing based on the SG algorithm. It is a flowchart which shows an example of the radio resource allocation processing executed by a resource allocation part. It is explanatory drawing which shows an example of resource allocation for each new construction of a roadside machine. It is explanatory drawing which shows an example of resource allocation for each new construction of a roadside machine. It is explanatory drawing which shows an example of resource allocation for each new construction of a roadside machine. It is explanatory drawing which shows an example of resource allocation for each new construction of a roadside machine. It is explanatory drawing which shows another example of resource allocation for each new construction of a roadside machine. It is explanatory drawing which shows another example of resource allocation for each new construction of a roadside machine.

<Outline of Embodiment of the present invention>
Hereinafter, the outlines of the embodiments of the present invention will be described in a list.
(1) The allocation method of the present embodiment is a method of allocating radio resources to the roadside unit of the ITS radio, and is assigned to the cell when only the position information of the newly installed roadside unit is included in the cell of the VC map. The first step of applying VC allocation to the new roadside machine, and when the VC map cell contains the position information of the new roadside machine and the position information of other roadside machines, the new roadside machine For the roadside machine, the second step of performing PSG allocation for allocating radio resources by the PSG algorithm is included.

According to the allocation method of the present embodiment, VC allocation is performed when only the position information of the new roadside machine is included in the cell of the VC map (first step), and the position information of the new roadside machine is included in the cell of the VC map. Since PSG allocation is performed when the position information of the other roadside aircraft is included (second step), it is possible to appropriately allocate radio resources to the newly installed roadside aircraft by using both the VC algorithm and the PSG algorithm.

(2) In the allocation method of the present embodiment, it is preferable to further include a third step of setting the PSG area defined below when the PSG allocation is performed in the second step.
PSG area: An area consisting of a plurality of cells contained in a rectangular area vertically and horizontally separated by a predetermined non-interference distance centering on a cell including a roadside machine to which PSG allocation is performed.

By doing so, it becomes possible to determine the type of allocation processing to be applied to the subsequent new roadside machine depending on whether the position information of the new roadside machine is inside or outside the PSG area set in the third step.

(3) Specifically, in the allocation method of the present embodiment, when the position information of the newly installed roadside machine is inside the PSG area, the fourth step of performing the PSG allocation for the newly installed roadside machine is performed. , You can do more.
The reason is that when the position information of the new roadside aircraft is inside the PSG area, it is necessary to consider the interference relationship with the existing roadside aircraft to which PSG allocation has been made. This is because the radio resources should be allocated.

(4) Further, in the allocation method of the present embodiment, when the position information of the newly installed roadside machine is outside the PSG area, the fifth step of performing the VC allocation for the newly installed roadside machine is further executed. do it.
The reason is that when the position information of the newly installed roadside unit is outside the PSG area, it has a non-interfering relationship with the existing roadside unit to which PSG allocation has been made, so the radio resource allocated to the cell in the VC area is used. This is because it does not matter if it is adopted as it is.

(5) In the allocation method of the present embodiment, when the PSG allocation is performed in the fourth step, the sixth step of further setting the PSG area for the roadside machine to which the PSG allocation is performed is further included. Is preferable.
By doing so, it becomes possible to determine the type of allocation processing to be applied to the subsequent new roadside machine depending on whether the position information of the new roadside machine is inside or outside the PSG area set in the sixth step.

(6) In the allocation method of the present embodiment, it is preferable that the cells of the VC map are set to a size such that the required number of resources is less than 16 (for example, 12 in the example of FIG. 2) or less.
By doing so, for example, it becomes possible to secure an empty slot for a roadside machine installed at an important intersection. Therefore, even if the installation of the roadside machine at the general intersection precedes, it becomes easy to allocate the radio resource to the roadside machine newly installed at the important intersection.

(7) The allocation device of the present embodiment is a radio resource allocation device that executes the above-mentioned allocation methods (1) to (6).
Therefore, the allocation device of the present embodiment has the same effect as the allocation method of (1) to (6) described above.

(8) The computer program of the present embodiment is a computer program for operating a computer as the allocation device of the above-mentioned (7).
Therefore, the computer program of the present embodiment has the same effect as that of the allocation device of (7) described above.

<Details of the Embodiment of the present invention>
Hereinafter, the details of the embodiment of the present invention will be described with reference to the drawings. In addition, at least a part of the embodiments described below may be arbitrarily combined.

[Configuration of wireless resource allocation device]
FIG. 1 is a block diagram showing a configuration example of the radio resource allocation device 1 according to the present embodiment.
As shown in FIG. 1, the radio resource allocation device 1 includes a storage unit 11 and an information processing unit 12, and includes a computer device in which an OS (operating system) and various application programs are installed. Although not shown, the allocation device 1 also includes a display device such as a liquid crystal display and an input device such as a mouse and a keyboard.

The storage unit 11 is a storage including at least one non-volatile memory (storage medium) of an HDD (Hard Disk Drive) and an SSD (Solid State Drive), and a volatile memory (storage medium) including a random access memory or the like. It is a device.
The information processing unit 12 comprises an arithmetic processing unit including a CPU (Central Processing Unit) that reads a computer program 13 stored in the non-volatile memory of the storage unit 11 into the volatile memory and performs information processing according to the program 13.

In addition to the computer program 13, map information 14 and area information 15 are stored in the storage unit 11.
The map information 14 is composed of digital map data covering the whole of Japan. The digital map data includes road map data 18. Road map day 18 includes "intersection data" and "link data".

The "intersection data" is data in which the intersection ID given to the intersection in Japan and the position information of the intersection are associated with each other. The "link data" is composed of data in which the following information 1) to 4) are associated with the link ID of the specific link given corresponding to the domestic road.
Information 1) Position information of start point / end point / interpolation point of specific link Information 2) Link ID to connect to the start point of specific link
Information 3) Link ID that connects to the end point of a specific link
Information 4) Link cost of a specific link

The road map data 18 constitutes a network corresponding to the actual road alignment and the traveling direction of the road. Therefore, the road map data 18 is a network in which road sections between nodes representing intersections are connected by a directed link l (lowercase letter L).
Specifically, the road map data 18 is composed of a directed graph in which nodes n are set for each intersection and each node n is connected by a pair of directed links l in opposite directions. Therefore, in the case of a one-way road, the node n is connected only to the directed link l in one direction.

The area information 15 includes the VC map 19. The VC map 19 is composed of mesh data in which digital map data covering the whole of Japan is divided by cells C of a predetermined size. The particle size of the mesh is arbitrary, but in the present embodiment, for example, a fifth-order mesh is adopted. Therefore, one side of the cell C is 250 m.

Each cell C of the VC map is assigned the identification information (mesh code) of the cell C and the slot number (radio resource) that can be used by the roadside machine located in the cell C.
In the example of FIG. 1, slot numbers of "3", "4", "5", "1", "2" ... Are assigned in order from the upper left corner to the right side. The allocation of radio resources to each cell C is executed by the VC map generation unit 16 based on the VC (Vector-based Cell Cover) algorithm, which will be described later.

The area information 15 includes a PSG (Prioritized Station-based Greedy) area 20. The PSG area 20 is an area that the resource allocation unit 17 superimposes on the VC map 19.
When the resource allocation unit 17 executes resource allocation based on the PSG algorithm for the newly installed roadside machine, the resource allocation unit 17 is placed in a rectangular area vertically and horizontally separated from the cell C by a predetermined non-interference distance with the cell C including the new roadside machine as the center. A plurality of included cells C are set in the PSG area.

The information processing unit 12 includes a VC map generation unit 16 and a resource allocation unit 17. These are functional units achieved by the information processing unit 12 reading the computer program 13 from the storage unit 11 and executing it.

The VC map generation unit 16 generates a VC map 19 from the map information 14 and stores it in the storage unit 11. The details of the generation process executed by the VC map generation unit 16 will be described later.
The resource allocation unit 17 determines the radio resource (time slot) to be allocated to the new roadside machine based on the position information of the new roadside machine input by the user and the area information 15 stored in the storage unit 11. The details of the allocation process executed by the resource allocation unit 17 will also be described later.

[Conditions for using wireless resources and conditions for installing roadside units]
FIG. 2 is an explanatory diagram of radio resource usage conditions and roadside unit installation conditions.
As shown in FIG. 2, the radio resource to be allocated includes a plurality of time slots SL1 to SL16 arranged in a time division manner in one control cycle. The time slots SL1 to SL16 are transmittable times of the ITS roadside unit (base station).

The plurality of time slots SL1 to S16 are included in one control cycle for a predetermined time (100 ms), and the control cycle occurs repeatedly. In one control cycle, the period between the time slots SL1 and S16 is used for wireless communication of a mobile station such as an on-board unit.
Such time slots SL1 to SL16 are defined in the 700 MHz band intelligent transportation system (ARIB STD-T109).

In the road map (intersection NW) of FIG. 2, the meanings of "A" to "I" are as follows.
A: Roadside machine installed at an important intersection (connected to the central device by a dedicated line)
B to E: Roadside unit for relay installed at general intersections (not connected to central equipment)
FI: Roadside machine at the end installed at a general intersection (not connected to the central device)

As shown in FIG. 2, the usage conditions of the time slots SL1 to SL16 are as follows.
Slots SL1 and SL2: Used for road-to-vehicle communication of roadside machine A.
Slots SL3 to SL12: For VC / PSG allocation.
Slots SL13, SL14: Open for inter-road communication when interference occurs at an important intersection.
Slots SL15, SL16: For inter-road communication of roadside machines A to I.

The installation conditions for the new roadside unit are the following conditions 1 and 2.
Condition 1: One roadside machine is installed in the VC cell.
Condition 2: The installation interval of the roadside machine with respect to the important intersection shall be a predetermined interference distance (for example, 1180 m) or more.

[Processing content of VC map generator]
FIG. 3 is an explanatory diagram showing an example of the processing content of the VC map generation unit 16.
As described above, the VC map generation unit 16 determines a cell size suitable for the above installation conditions based on the VC algorithm, and generates a VC map 19 in which radio resources are allocated to each cell C. Hereinafter, the outline of the method of generating the VC map 19 based on the VC algorithm will be described with reference to FIG.

The VC algorithm includes the following steps 1 to 4.
Step 1: Partitioning the installation area Step 1 is a process of partitioning the installation area of the roadside machine into cells C of a predetermined size.
As shown in FIG. 3A, the installation area of the roadside machine is divided into cells C having a predetermined size. In FIG. 3A, the installation area of the roadside machine is indicated by an area within a predetermined range including the grid-like road R, and the intersection where the roadside machine is installed is indicated by a black circle. The size of the cell C is preferably a size that can divide the interference range by the number of divisions that does not exceed the number of VC / PSG allocation slots (12 in this embodiment) set in advance as the usage condition of the time slot.

2) Step 2: Search for non-interfering cell Step 2 is a process for searching for another non-interfering cell C for each cell C.
In the VC algorithm, the interference relationship is considered for each cell, not the actual installation position of the roadside machine. Specifically, for each cell C, an "interference cell" having an interference relationship with the cell C and a "non-interference cell" having a non-interference relationship are searched for. In FIG. 3A, the cell C2 is an interfering cell and the cell C3 is a non-interfering cell with respect to the cell C1.

3) Step 3: Allocation of radio resources and calculation of the number of resources In step 3, different radio resources (time slots) are regularly assigned to the interfering cells, and the same radio resources (time slots) are assigned to the non-interfering cells. This is a process to find the number of resources required in the installation area.
In FIG. 3B, different time slots are assigned to the interfering cell C1 and the cell C2, and the same radio resource is assigned to the non-interfering cell C1 and the cell C3.

4) Step 4: Specifying the cell size In step 4, the cell size is changed variously and the processes of steps 1 to 3 are repeated, and the number of resources required in the installation area does not exceed the number of slots for VC / PSG allocation. Moreover, it is a process of specifying the minimum cell size.
In FIG. 3B, the cell size is such that the installation area is divided into 7 vertical × 9 horizontal, and the number of resources is 5 with slot numbers 1 to 5.

The VC map generation unit 16 expands the installation area shown in FIG. 3 to the range of digital map data covering the whole of Japan, and allocates radio resources to each cell C included in the range. Therefore, the range of VC map 19 covers a wide area covering the whole of Japan.

[Allocation processing by SG and PSG algorithms]
FIG. 4 is an explanatory diagram showing an example of an allocation process based on an SG (Station-based Greedy) algorithm. In FIG. 4, R1 to R26 are roadside machines located at each intersection.
First, as shown in FIG. 4A, the roadside machine R15 having the highest installation density is selected as the target roadside machine, and radio resources (here, tentatively referred to as the time slot SL11) are allocated. The target roadside machine R15 is the first roadside machine to which the time slot SL11 is assigned.

Next, a roadside machine that allocates the same radio resources as the target roadside machine R15 is searched for.
Specifically, the interference relationship between the target roadside machine R15 and the other roadside machines R1 to R14 and R16 to R26 is calculated, and the target roadside machine R15 is the first non-interfering roadside machine (target) that does not serve as an interference source. A roadside machine that does not receive interference from the roadside machine R15) is extracted (see FIG. 4A).
For example, the radio wave interference given from the target roadside machine R15 into the communication area E of the roadside machine R9 is calculated, and if the radio wave interference is weak, the roadside machine R9 is extracted as the first non-interfering roadside machine.

Next, based on the calculation result of the interference relationship, among the first non-interfering roadside machines of FIG. 4A, the second non-interfering roadside machine (interference with the target roadside machine R15) that does not become an interference source to the target roadside machine R15. The roadside machine that is not given) is extracted (see FIG. 4B).
For example, among the first non-interfering roadside machines, the radio wave interference given by the roadside machine R4 or the roadside machine R9 into the communication area E of the target roadside machine R15 is calculated, and if the radio wave interference is strong, the roadside machine R4 or the roadside machine R9 Is not extracted as the second non-interfering roadside machine.

In FIG. 4B, the roadside machines R1, R5, R6, R8, R21, R22, and R26 are extracted as the second non-interfering roadside machines.
The same radio resources as the target roadside machine R15 can be assigned to the second non-roadside interference roadside machine. Of these, the same radio resource (time slot SL11) as the target roadside machine R15 is allocated to the roadside machine having the shortest distance from the target roadside machine R15 or the highest density of the roadside machine.

Here, for example, the same radio resource (time slot SL11) as the target roadside machine R15 is allocated to the roadside machine R22.
Subsequently, among the second non-interfering roadside machines, when the roadside machine having the shortest distance from the target roadside machine R15 or the highest density of the roadside machines is the roadside machine R8 next to the roadside machine R22. If the roadside machine R8 does not have a mutual interference relationship with the roadside machine R22 in addition to the roadside machine R15, the same radio resources as the target roadside machine R15 are allocated to the roadside machine R8.

On the other hand, if there is a mutual interference relationship, an attempt is made to allocate radio resources different from those of the roadside machine R15 and the roadside machine R22. At this time, if there is no other roadside machine to which the different radio resource (for example, time slot SL12) is assigned, the same processing as that of the roadside machine R15 is performed.
If there is another roadside machine to which the different radio resource is assigned, the same processing as that performed when the roadside machine R15 is in the time slot SL11 is performed.

By repeating this for a plurality of second non-interfering roadside machines in the time slot SL11, the roadside machines R6, R8, R22, and R26 to which the same radio resources (time slot SL11) as the target roadside machine R15 can be allocated are determined. (See FIG. 4C).
When the above processing is completed, the processing of FIGS. 4A to 4C is repeated with the roadside machine (for example, the roadside machine R10) in the vicinity of the target roadside machine R15 as the next target roadside machine. This determines which radio resource can be allocated to the roadside unit installed in the predetermined mutual interference area.

The PSG algorithm allocation process is a process in which the above SG algorithm allocation process is performed under a weighted condition that the radio resource of the existing roadside machine is not changed.

[Processing content of resource allocation section]
FIG. 5 is a flowchart showing an example of the radio resource allocation process executed by the resource allocation unit 17.
As shown in FIG. 5, the resource allocation unit 17 triggers the user to input the operation of the position information of the newly installed roadside machine (Yes in step ST11), and whether or not the input position information of the roadside machine is in the PSG area 20. (Step ST12).

The above operation input of the position information can be performed, for example, by moving the mouse pointer onto the intersection of the road map displayed on the display and clicking the mouse on the intersection.
The determination in step ST12 is performed depending on whether or not the cell C including the position information (coordinate value) of the roadside machine designated by the pointer is designated as the PSG area 20 of the area information 15.

When the determination result in step ST12 is negative (when the position information is outside the range of the PSG area 20), the resource allocation unit 17 determines whether the position information is the only position information in the cell C of the VC map 19. (Step ST13).
Since the PSG area 20 is created when the PSG allocation described later is implemented (steps ST15 and ST16), the PSG area 20 does not exist if the PSG allocation has never been implemented in the past. , The determination result in step ST12 is always negative.

If the determination result in step ST13 is affirmative, the resource allocation unit 17 executes "VC allocation" for the input new roadside machine (step ST15).
The “VC allocation” is a process of applying the radio resource allocated to the cell C of the VC map 19 as it is to the new roadside machine. Therefore, when the slot number of the cell C including the position information is "3", the time slot SL3 is applied to the new roadside machine.

If the determination result in step ST12 is positive, or if the determination result in step ST13 is negative, the resource allocation unit 17 executes "PSG allocation" (step ST15).
The “PSG allocation” is a process of allocating radio resources based on the PSG algorithm described above, instead of applying the slot number of the cell C as it is to the newly installed roadside machine.

When the PSG allocation (step ST15) is performed, the resource allocation unit 17 creates the PSG area 20 and updates the area information 15 by adding the created PSG area 20 to the area information 15 of the storage unit 11 (step ST15). Step ST16).
For example, the resource allocation unit 17 may use PSG for a plurality of cells C included in a rectangular region vertically and horizontally separated from the cell C by a predetermined non-interference distance (for example, 1180 m) with the cell C including the newly constructed roadside machine as the center. Designated as area 20.

[Resource allocation for each new roadside machine]
6 to 9 are explanatory views showing an example of resource allocation for each new installation of the roadside machine.
The screens 1 to 6 of FIGS. 6 to 9 are display screens of digital map data displayed on the display of the wireless resource allocation device 1. The straight line included in the screen 1 of FIG. 6 indicates a “road” in the digital map data, and the intersection of the straight lines indicates an “intersection”. In addition, in order to avoid the complexity of the illustration, the road display is omitted on the screen 2 and subsequent screens.

On screens 1 to 6, Rj (j = 1 to 7) is a roadside machine designated to be installed at a "general intersection". The subscript j of Rj represents the order in which the installation is specified by the user.
In screens 1 to 6, "VC" indicates that "VC allocation" (step ST14 in FIG. 5) has been performed for the roadside machine. “PSG” indicates that “PSG allocation” (step ST15 in FIG. 5) has been carried out for the roadside aircraft.

In screens 1 to 6, the white square dots indicate the existing roadside machines at the present time, and the black-painted square dots indicate the new roadside machines that the user has newly specified to be installed.
Although cells C and PSG areas 20A and 20B of the VC map 19 are displayed on the screens 2 to 6, the cells C and PSG areas 20A and 20B do not necessarily have to be displayed on the display.

The screen 1 of FIG. 6 is a display screen when the installation of the roadside machine is already specified in the order of the roadside machine R1 → the roadside machine R2 → the roadside machine R3, and the new installation of the roadside machine R4 is specified. Here, it is assumed that the position information of the roadside machines R1 to R4 is unique in the cell C of the VC map 19.
In this case, the resource allocation unit 17 executes VC allocation to the roadside machines R1 to R4 (steps ST12 to ST14 in FIG. 5). Therefore, for the roadside machines R1 to R4, the time slot assigned to the cell C of the VC map 19 is applied.

Screen 2 of FIG. 7 is a display screen when the installation of roadside machines R1 to R4 (all are assigned to VCs) is already specified at the four intersections and the new installation of roadside machines R5 is specified. Here, it is assumed that the position information of the designated roadside machine R5 is in the cell C including the position information of the existing roadside machine R4.
In this case, the resource allocation unit 17 executes PSG allocation to the newly installed roadside machine R5 (steps ST12, ST13, ST15 in FIG. 5). Therefore, for the roadside machine R5, the time slot determined by PSG allocation is applied.

As shown in screen 3 of FIG. 7, when PSG allocation is performed for the newly installed roadside machine R5, the resource allocation unit 17 sets the PSG area 20A centered on the cell C including the roadside machine R5 (step of FIG. 5). ST16).
After that, depending on whether the position information of the new roadside machine specified by the user is inside or outside of the PSG area 20A, it is determined whether the resource allocation type applied to the new roadside machine is PSG allocation or VC allocation (Fig.). Step 7 ST12).

The screen 4 of FIG. 8 is a display screen when the PSG area 20A is set with the installation of the roadside machine R5 and then the new installation of the roadside machine R6 is designated outside the PSG area 20A. Here, it is assumed that the position information of the roadside machine R6 is unique in the cell C of the VC map 19.
In this case, the resource allocation unit 17 executes VC allocation to the roadside machine R6 (steps ST12 to ST14 in FIG. 5). Therefore, for the roadside machine R6, the time slot assigned to the cell C of the VC map 19 is applied.

The screen 5 of FIG. 8 is a display screen when the PSG area 20A is set with the installation of the roadside machine R5 and then the new installation of the roadside machine R7 is designated inside the PSG area 20A.
In this case, the resource allocation unit 17 executes PSG allocation to the roadside machine R7 (steps ST12 and ST15 in FIG. 5). Therefore, for the roadside machine R7, the time slot determined by PSG allocation is applied.

As shown in screen 6 of FIG. 9, when PSG allocation is performed for the newly installed roadside machine R7, the resource allocation unit 17 further sets the PSG area 20B centered on the cell C including the roadside machine R7 (FIG. 5). Step ST16).
After that, depending on whether the position information of the new roadside machine specified by the user is inside or outside of the PSG areas 20A and 20B, it is determined whether the resource allocation type applied to the new roadside machine is PSG allocation or VC allocation. (Step ST12 in FIG. 7).

[First modification: When adding a roadside machine to an important intersection]
FIG. 10 is an explanatory diagram showing another example of resource allocation for each new installation of the roadside machine.
The screens 7 and 8 of FIG. 10 are also display screens of digital map data displayed on the display of the wireless resource allocation device 1, but the display of roads is omitted.

In screens 7 and 8 of FIG. 10, Ra to Rc are roadside machines designated to be installed at "important intersections". The subscripts a to c of Ra to Rc represent the order in which the installation is specified by the user.
Here, as described above, it is assumed that the time slots SL1, SL2, SL13, and SL14 for the roadside machine installed at the important intersection are reserved in advance. Therefore, for the roadside machine Ra that is first designated to be installed at an important intersection, the resource allocation unit 17 has one of the time slots reserved in advance, regardless of which area the position information of the roadside machine Ra is. For example, slot SL1) is assigned.

The screen 7 of FIG. 10 is a display screen when the installation of the roadside machine at an important intersection is specified in the order of roadside machine Ra → roadside machine Rb → roadside machine Rc. Here, the position information of the second roadside machine Ra is outside the important intersection interference area 21 with the roadside machine Ra, and the position information of the third roadside machine Rc is the important intersection interference area 21 of the roadside machine Ra. Suppose it is inside.
The important intersection interference area 21 is composed of a plurality of cells C included in a rectangular area vertically and horizontally separated by a predetermined non-interference distance (for example, 1180 m) from the cell C including the roadside machine Ra.

Since the resource allocation unit 17 does not interfere with the first roadside machine Ra with respect to the second roadside machine Ra, the resource allocation unit 17 allocates the same time slot (for example, slot SL1) as the first roadside machine Ra.
Since the resource allocation unit 17 interferes with the first roadside machine Ra for the third roadside machine Rc, PSG allocation is performed.

As shown in screen 8 of FIG. 10, when PSG allocation is performed for the newly installed roadside machine Rc, the resource allocation unit 17 further sets a PSG area 20C centered on the cell C including the roadside machine Rc.
After that, depending on whether the position information of the new roadside machine specified by the user is inside or outside of PSG areas 20A to 20C, it is determined whether the resource allocation type applied to the new roadside machine is PSG allocation or VC allocation. (Step ST12 in FIG. 7).

[Second variant: reassignment when there are no empty slots]
FIG. 11 is an explanatory diagram showing another example of resource allocation for each new installation of the roadside machine.
The screens 9 and 10 of FIG. 11 are also display screens of digital map data displayed on the display of the wireless resource allocation device 1, but the display of the road is omitted.

In screens 9 and 10 of FIG. 11, R8 is a roadside machine designated to be newly installed at a "general intersection".
Here, as shown in the screen 9 of FIG. 11, the position information of the roadside machine R8 is inside the existing PSG areas 20A to 20C, and even if the PSG allocation of the roadside machine R8 is performed, the roadside to be installed at the general intersection. It is assumed that there is no space in the time slots SL3 to SL12 for the machine R8.

In this case, the resource allocation unit 17 sets the reallocation area 22 for the roadside machine R8 as shown in the screen 10 of FIG. The reassignment area 22 is composed of a plurality of cells C included in a rectangular area vertically and horizontally separated by a predetermined non-interference distance (for example, 1180 m) from the cell C including the roadside machine R8.
Then, the resource allocation unit 17 performs PSG allocation for all the roadside machines R4 to R8, Ra, Rc included in the reallocation area 22, and reallocates the radio resources.

By doing so, the PSG allocation to the existing roadside machines R4 to R7, Ra, Rc may cause a vacancy in the time slot for the roadside machine 8, and the radio resource allocation to the new roadside machine R8 may occur. It can be possible.

[Other variants]
The above-described embodiments (including modifications) are exemplary in all respects and are not restrictive. The scope of rights of the present invention includes all modifications within the same scope as the configurations described in the claims.

For example, in the above-described embodiment, the VC map generation unit 16 does not necessarily have to be mounted on the radio resource allocation device 1, and may be present in another computer device. In this case, the VC map 19 generated by another computer device may be installed in the storage unit 11.

1 Wireless resource allocation device 11 Storage unit 12 Information processing unit 13 Computer program 14 Map information 15 Area information 16 VC map generation unit 17 Resource allocation unit 18 Road map data 19 VC map 20 PSG area 20A to 20C PSG area 21 Important intersection interference area 22 Reallocation area

Claims (8)

It is a method of allocating radio resources to roadside units of ITS radio.
When the cell of the VC map contains only the position information of the newly installed first roadside machine, the first step of performing VC allocation to apply the radio resource allocated to the cell to the first roadside machine, and
When the cell of the VC map contains the position information of the newly installed first roadside machine and the position information of other roadside machines, the radio resources of the first roadside machine are not changed by the PSG algorithm that does not change the radio resources of the existing roadside machine. A method of allocating radio resources, including a second step of performing PSG allocation. The radio resource allocation method according to claim 1, further comprising a third step of setting a PSG area defined below when the PSG allocation is performed in the second step.
PSG area: An area consisting of a plurality of cells contained in a rectangular area vertically and horizontally separated by a predetermined non-interference distance centering on a cell including a roadside machine to which PSG allocation is performed. Claim 2 further includes a fourth step of assigning the PSG to the second roadside machine when the position information of the newly installed second roadside machine different from the first roadside machine is inside the PSG area. The radio resource allocation method described. Claim 3 further includes a fifth step of assigning the VC to the second roadside machine when the position information of the newly installed second roadside machine different from the first roadside machine is outside the PSG area. The radio resource allocation method described. Claim 3 or claim 4 further includes a sixth step of setting the PSG area for the second roadside machine to which the PSG allocation is made when the PSG allocation is made in the fourth step. The radio resource allocation method described. The radio resource allocation method according to any one of claims 1 to 5, wherein the cells of the VC map are set to a size such that the required number of resources is less than 16 and equal to or less than a predetermined number. A device that allocates radio resources to roadside units of ITS radio.
A storage unit that stores a VC map created based on the VC algorithm,
The information processing unit that determines whether the VC allocation or PSG allocation defined below is applied to the new roadside machine, depending on whether the position information of the new roadside machine is unique in the cell of the VC map. A radio resource allocation device equipped with.
VC allocation: Process of applying the radio resource of the cell of the VC map to the new roadside machine PSG allocation: Process of allocating the radio resource to the new roadside machine by the PSG algorithm that does not change the radio resource of the existing roadside machine A computer program for operating a computer as a device for allocating radio resources to a roadside unit of ITS radio.
To the computer
When the cell of the VC map contains only the position information of the new roadside machine, the first step of performing VC allocation to apply the radio resource allocated to the cell to the new roadside machine, and
When the VC map cell contains the position information of a new roadside machine and the position information of another roadside machine, the radio resource of the new roadside machine is based on the PSG algorithm that does not change the radio resource of the existing roadside machine. A computer program that executes the second step of performing PSG allocation.

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