JP7440404B2 - Frequency mapping device, frequency mapping method and computer program - Google Patents

Description

The present invention relates to a frequency mapping device, a frequency mapping method, and a computer program.

In recent years, in order to cope with the increasing demand for mobile traffic, consideration has been given to having multiple different wireless communication systems share the same frequency band. For example, consideration is being given to allowing other wireless communication systems (secondary carrier systems) to use frequency bands assigned to existing wireless communication systems on a secondary basis. In this frequency sharing between different systems, the secondary carrier system uses vacant resources that are not used by the existing wireless communication system that is given absolute priority. A frequency allocation technique for allocating a frequency band (shared frequency band) shared by an existing wireless communication system and a secondary carrier system to a secondary carrier system is described in Non-Patent Document 1, for example. The frequency allocation technique described in Non-Patent Document 1 is designed to maximize the throughput of the entire system for a wireless communication system that can tolerate radio wave interference between base stations.

“Communication-Free Inter-Operator Interference Management in Shared Spectrum Small Cell Networks”, IEEE Transactions on Cognitive Communications and Networking, VOL. 5, NO. 3, Sept. 2019

However, in the frequency allocation technique described in Non-Patent Document 1 mentioned above, when the number of base stations to be allocated increases, the amount of variables to be determined increases exponentially, so the time required for allocation calculation increases. There was a problem in that the allocation process could not be completed within a desired time.

The present invention has been made in consideration of these circumstances, and its purpose is to appropriately compress the number of base stations in the allocation calculation in the allocation of the shared frequency band. The purpose of this invention is to shorten the time required for allocation calculation.

(1) One aspect of the present invention is an information input unit that receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band; A virtual base station that extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and sets the extracted base station combinations and other remaining base stations as virtual base stations, respectively. A setting unit executes a mapping calculation to allocate a frequency channel and time slot of the shared frequency band to each of the virtual base stations, and from the result of the mapping calculation, determines a frequency channel of the shared frequency band to be allocated to each of the base stations. and a mapping calculation unit that calculates time slots, and an allocation result output unit that outputs allocation result information indicating the allocation results of the frequency channels and time slots of the shared frequency band allocated to each of the base stations. It is.
(2) In one aspect of the present invention, the virtual base station setting unit extracts base station combinations in which the amount of interference between base stations is less than or equal to a threshold value from the plurality of base stations in order of decreasing bandwidth demand difference between the base stations. This is the frequency mapping device according to (1) above, which is set as a virtual base station.
(3) In one aspect of the present invention, the virtual base station setting unit selects combinations in which the amount of interference between the virtual base station and the remaining base stations and between the virtual base stations is equal to or less than a threshold value. This is the frequency mapping device according to (2) above, which extracts the base stations in order of decreasing difference and further sets the base stations as virtual base stations.
(4) One aspect of the present invention is that the virtual base station setting unit adjusts the number of virtual base stations by increasing the interference amount threshold in stages, It is a mapping device.

(5) In one aspect of the present invention, the mapping calculation unit calculates, during the mapping calculation period, a band acquisition rate, a frequency continuity value, a time continuity value, and a spatial continuity value of the shared frequency band of each of the virtual base stations. From (1) above, a frequency channel of the shared frequency band to be allocated to each virtual base station in each time slot is determined using an objective function that calculates the sum of the objective functions so that the value of the objective function is maximized. 4) is any one of the frequency mapping devices.

(6) In one aspect of the present invention, the frequency mapping device receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources in the shared frequency band. an information input step, the frequency mapping device extracting a base station combination in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and comparing the extracted base station combination with other remaining base stations; a virtual base station setting step of setting each virtual base station to a virtual base station, and the frequency mapping device executes a mapping calculation to allocate a frequency channel and time slot of the shared frequency band to each of the virtual base stations, a mapping calculation step of determining the frequency channel and time slot of the shared frequency band to be assigned to each base station from the results of the above; This frequency mapping method includes an allocation result output step of outputting allocation result information indicating a slot allocation result.

(7) One aspect of the present invention is an information input that allows a computer to receive input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band. step, extracting base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and setting each of the extracted base station combinations and the remaining base stations as virtual base stations. a virtual base station setting step, and a mapping calculation for allocating frequency channels and time slots of the shared frequency band to each of the virtual base stations, and based on the results of the mapping calculation, the shared frequency band to be allocated to each of the base stations; a mapping calculation step for determining frequency channels and time slots of the shared frequency band assigned to each of the base stations; and an assignment result output step of outputting assignment result information indicating the assignment results of the frequency channels and time slots of the shared frequency band assigned to each of the base stations. It is a computer program for making

According to the present invention, when allocating a shared frequency band, by appropriately compressing the number of base stations in the allocation calculation, it is possible to appropriately allocate the shared frequency band and shorten the time required for the allocation calculation. can get.

FIG. 1 is a block diagram illustrating a configuration example of a frequency mapping device according to an embodiment. 3 is a flowchart illustrating an example of the overall procedure of a frequency mapping method according to an embodiment. 3 is a flowchart illustrating an example of a procedure of a mapping calculation method according to an embodiment. FIG. 2 is an explanatory diagram of a virtual base station setting method according to an embodiment. FIG. 2 is an explanatory diagram of a virtual base station setting method according to an embodiment. FIG. 2 is an explanatory diagram of a virtual base station setting method according to an embodiment. FIG. 2 is an explanatory diagram of a virtual base station setting method according to an embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram illustrating a configuration example of a frequency mapping device according to an embodiment. In FIG. 1, the frequency mapping device 1 includes an information input section 11, a mapping calculation section 12, an allocation result output section 13, an allocation result database (allocation result DB) 14, and a virtual base station setting section 20.

Each function of the frequency mapping device 1 is realized by the frequency mapping device 1 being equipped with computer hardware such as a CPU (Central Processing Unit) and memory, and the CPU executing a computer program stored in the memory. be done. Note that the frequency mapping device 1 may be configured using a general-purpose computer device, or may be configured as a dedicated hardware device. Moreover, the frequency mapping device 1 may be realized by a single computer, or the functions of the frequency mapping device 1 may be realized by distributing it to a plurality of computers.

The frequency mapping device 1 executes a frequency mapping process that allocates a frequency channel in each time slot of a shared frequency band to a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems. . As an example of the present embodiment, the frequency mapping device 1 allows a plurality of other wireless communication systems (secondary carrier systems) to secondarily use a frequency band allocated to an existing wireless communication system (existing system). In this case, vacant resources in the frequency band (shared frequency band) are allocated to the base stations of each secondary carrier system. The vacant resources of the shared frequency band are the resources of the shared frequency band that are not used by the existing system.

In the frequency mapping process according to the present embodiment, the number of base stations to be allocated is appropriately compressed in the allocation calculation (mapping calculation). This aims to appropriately allocate the shared frequency band and shorten the time required for allocation calculation (mapping calculation). Note that in the following description, radio wave interference may be simply referred to as interference.

The information input unit 11 receives input of base station information 111 and shared frequency band available resource information 112. The base station information 111 is information on the base station of a secondary carrier system that requests a shared frequency band, and includes the carrier name and number of the secondary carrier system, requested bandwidth, and request for each time slot. This information indicates usage time, requested usage location, base station parameters, etc. The vacant resource information 112 is information on vacant resources in the shared frequency band, and is information indicating vacant frequency channels in each time slot.

The virtual base station setting unit 20 extracts base station combinations in which the amount of interference between base stations is less than a threshold value from a plurality of base stations requesting a shared frequency band, and selects the extracted base station combinations and other remaining base station combinations. and the respective base stations are set as virtual base stations. The virtual base station becomes an allocation target in the mapping calculation. The number of base stations is compressed so that the number of virtual base stations is smaller than the original number of base stations requesting the shared frequency band.

The mapping calculation unit 12 allocates vacant resources of the shared frequency band to the base stations of each secondary carrier system based on the information input by the information input unit 11. In allocating this free resource, the mapping calculation unit 12 performs mapping calculation to allocate frequency channels and time slots of the shared frequency band to each virtual base station, and based on the result of the mapping calculation, the Find the frequency channel and time slot of the frequency band. Details of this mapping calculation method will be described later.

The allocation result output unit 13 outputs allocation result information 120 indicating the allocation result of the mapping calculation unit 12 allocating vacant resources of the shared frequency band to the base stations of each secondary carrier system. The allocation result information 120 is information indicating the allocation result of the frequency channel allocated to each base station in each time slot among the available resources of the shared frequency band. The allocation result information 120 of each secondary operator system is notified to each secondary operator system. Each secondary carrier system uses the shared frequency band according to its own allocation result shown in the allocation result information 120.

The allocation result DB 14 stores the results of allocation of frequency channels and time slots in the shared frequency band by the mapping calculation unit 12.

Next, the overall procedure of the frequency mapping method according to this embodiment will be described with reference to FIG. 2. FIG. 2 is a flowchart illustrating an example of the overall procedure of the frequency mapping method according to the present embodiment.

(Step S1) The frequency mapping device 1 receives input of the base station information 111 and the available resource information 112 of the shared frequency band.

(Step S2) The frequency mapping device 1 performs mapping calculations to allocate vacant resources of the shared frequency band to the base stations of each secondary carrier system, based on the information received as input in step S1.

(Step S3) The frequency mapping device 1 stores the frequency channel and time slot assignment results of the shared frequency band assigned to the base stations of each secondary carrier system obtained in step S2 in the assignment result DB 14.

(Step S4) The frequency mapping device 1 outputs allocation result information 120 indicating the allocation result of the frequency channel and time slot of the shared frequency band allocated to the base station of each secondary carrier system determined in step S2. .

[Mapping calculation method]
Next, a mapping calculation method according to this embodiment will be explained with reference to FIG. FIG. 3 is a flowchart illustrating an example of the procedure of the mapping calculation method according to the present embodiment. In addition, below, for example, the subscript "a" may be written as "_a".

In the frequency mapping device 1, parameters, objective functions, and constraints used in frequency mapping processing are set in advance.

Parameters related to the frequency mapping process of this embodiment are shown in the following equation (1).

i is a company number that identifies the secondary company system. M is a set of operator numbers.
f is a frequency channel number that identifies a frequency channel in the shared frequency band. F is a set of frequency channel numbers of the shared frequency band.
t is a time slot number that identifies the time slot to which the shared frequency band is allocated. T is a set of time slot numbers.

n is a base station index that identifies the base station. N is a set of base station indices. The set N of base station indexes is composed of base station indexes of all base stations of all secondary carrier systems that use the shared frequency band secondarily.
p is a base station combination index that identifies a combination of base stations. P is a set of base station combination indexes.

δ is a threshold (interference threshold) for determining the amount of interference.

fd_n is the bandwidth demand of the shared frequency band requested by the base station (n).
x_n, f, t is the allocation result of the frequency channel (f) in the time slot (t) for the base station (n) (channel mapping, “1 is allocated, 0 is not allocated”).

Bs_n,p is the base station operation information indicating whether the base station (n) is in operation or not in operation (stopped) in the base station combination (p) (“1 is in operation, 0 is not in operation (stopped) )”).
BSset_p is operation information of base station combination (p).

It_p is the amount of interference of the base station combination (p), and is the maximum amount of interference among the amounts of interference of the base stations included in the base station combination (p). It_l,m is the amount of interference between two base stations, and is the amount of interference that the base station (l) gives to the base station (m).
Diff_p is the difference in bandwidth demand between base stations in base station combination (p).

q is a virtual base station index that identifies a virtual base station. Q is a set of virtual base station indices.
VBs_q is operating information of the virtual base station. "VBs_q=1" indicates that the base station in operation in the virtual base station (q) is in operation. “VBs_q=0” indicates that all base stations in the virtual base station (q) are not in operation (all base stations are stopped).
VIt_a,b is the amount of interference that the virtual base station (a) gives to the virtual base station (b), and is the maximum amount of interference in the virtual base station (b) when "VBs_a=1".
Vfd_q is the bandwidth demand of the shared frequency band in the virtual base station (q), and is the average value of the bandwidth demand of the operating base stations in the virtual base station (q).
vx_q, f, t is the allocation result (channel mapping, "1 is allocated, 0 is not allocated") of the frequency channel (f) in the time slot (t) for the virtual base station (q).

α is the weight vector of the objective function. Each element α_1, α_2, α_3, α_4 of the weight vector α is a weighting coefficient of each term of the objective function.

In this embodiment, a shared frequency band is allocated for each mapping calculation period. The length of the mapping calculation period is set in advance, for example, in consideration of the calculation time required for frequency mapping processing.

The subsequent processing is executed every mapping calculation period.

(Step S11) The mapping calculation unit 12 sets base station performance information Bs_n and base station combination performance information BSset_p based on the base station information 111.

(Step S12) The mapping calculation unit 12 calculates the amount of interference It_l,m based on the base station information 111. Next, the mapping calculation unit 12 calculates the amount of interference It_p of the base station combination (p). Furthermore, the mapping calculation unit 12 calculates the bandwidth demand difference Diff_p of each base station combination (p) based on the base station information 111.

(Step S13) The virtual base station setting unit 20 sets a virtual base station. The virtual base station setting unit 20 acquires information necessary for setting a virtual base station from the mapping calculation unit 12. The virtual base station setting section 20 passes the virtual base station setting result to the mapping calculation section 12.

(Virtual base station setting method)
Here, the virtual base station setting method according to this embodiment will be explained with reference to FIGS. 4 to 7. 4 to 7 are explanatory diagrams of a virtual base station setting method according to this embodiment.
The virtual base station setting unit 20 determines a base station combination (p) in which the amount of interference It_p is less than or equal to the interference threshold δ. In FIG. 4, five base stations BS1, BS2, BS3, BS4, and BS5 are shown. The virtual base station setting unit 20 determines whether the amount of interference It_p is less than or equal to the interference threshold δ for each base station combination (p) of the base stations BS1, BS2, BS3, BS4, and BS5. Further, the virtual base station setting unit 20 determines the magnitude relationship of the bandwidth demand difference Diff_p between the respective base station combinations (p).

Next, the virtual base station setting unit 20 extracts base station combinations (p) in descending order of bandwidth demand difference Diff_p from among the base station combinations (p) in which the amount of interference It_p is less than or equal to the interference threshold δ, and selects the base station combinations (p) in order of decreasing bandwidth demand difference Diff_p. Set combination (p) to virtual base station (q).

As a result of the determination in FIG. 4, as shown in FIG. 5, the base station combination (p) of base stations BS1 and BS3 is the base station combination in which the amount of interference It_p is less than or equal to the interference threshold δ and the bandwidth demand difference Diff_p is the smallest. (p). The virtual base station setting unit 20 sets the base station combination (p) of the base stations BS1 and BS3 as a virtual base station (q=1). Further, the virtual base station setting unit 20 sets the operation information VBs_1 of the virtual base station (1) from the operation information BSset_p of the base station combination (p) of the base stations BS1 and BS3.

Next, as shown in FIG. 6, the base station combination (p) of base stations BS2 and BS5 is selected as the base station combination (p) in which the amount of interference It_p is less than or equal to the interference threshold δ and the bandwidth demand difference Diff_p is the next smallest. Extracted. The virtual base station setting unit 20 sets the base station combination (p) of the base stations BS2 and BS5 as a virtual base station (q=2). Further, the virtual base station setting unit 20 sets the operation information VBs_2 of the virtual base station (2) from the operation information BSset_p of the base station combination (p) of base stations BS2 and BS5.

Next, as shown in FIG. 7, the virtual base station setting unit 20 sets the remaining base station BS4 as a virtual base station (q=3). Further, the virtual base station setting unit 20 sets operating information VBs_3 of the virtual base station (3) from the operating information of the base station BS4. Note that if only the base station combination (p) whose interference amount It_p exceeds the interference threshold δ remains, the virtual base station setting unit 20 individually configures the base stations of all the base station combinations (p). The virtual base station (q) is set, and the operation information VBs_q of the virtual base station (q) is set.

Next, the virtual base station setting unit 20 targets all the virtual base stations and selects one from among the virtual base station combinations in which the amount of interference VIt_a, b of the virtual base station is less than or equal to the interference threshold δ, similarly to the above-described procedure. , virtual base station combinations are extracted in order of decreasing difference in bandwidth demand Vfd_q of the virtual base stations, and the extracted virtual base station combinations are integrated into one virtual base station (q).

The virtual base station setting unit 20 repeats the above-described virtual base station setting operation until a predetermined virtual base station setting end condition is satisfied. The virtual base station setting termination condition is that the number of virtual base stations becomes less than or equal to a predetermined value (compression target number). Therefore, the virtual base station setting unit 20 repeats the above-described virtual base station setting operation until the number of virtual base stations becomes equal to or less than the compression target number.

The number of compression targets is set in advance, for example, taking into consideration the calculation time required for frequency mapping processing. Note that the more the number of base stations to be allocated in mapping calculations is compressed, the shorter the calculation time required for frequency mapping processing will be, but the overhead of converting base stations into virtual base stations will increase and frequency usage efficiency will decrease. The possibilities become greater. Therefore, from the viewpoint of maintaining frequency usage efficiency, it is preferable to avoid compressing the number of base stations more than necessary.

Note that in the virtual base station setting operation described above, the number of virtual base stations may be adjusted by changing the value of the interference threshold δ. For example, by increasing the interference threshold δ in stages, it is possible to efficiently extract base stations from combinations with a small amount of interference as virtual base stations.

The above is the explanation of the virtual base station setting method according to this embodiment.
The explanation returns to FIG. 3.

(Step S14) The mapping calculation unit 12 performs mapping calculation to allocate frequency channels and time slots of the shared frequency band to each virtual base station. Specifically, the mapping calculation unit 12 calculates the optimal solution "virtual base station allocation result vx_q, f, t" using the objective function. An objective function is set in the frequency mapping device 1 in advance. An example of the objective function according to this embodiment is shown in the following equation (2).

The objective function shown in equation (2) calculates the sum of the band acquisition rate, frequency continuity value, time continuity value, and spatial continuity value of the shared frequency band of each virtual base station (q) during the mapping calculation period. It is something. According to the frequency mapping process using the objective function of equation (2), it is possible to take into consideration the band acquisition rate, frequency continuity, time continuity, and spatial continuity of the shared frequency band.

In the above equation (2), the band acquisition rate is the ratio of the band allocated to the virtual base station (allocated band) to the shared frequency band requested by the virtual base station (bandwidth demand). Frequency continuity means that frequency channels are allocated consecutively in frequency to the same virtual base station in the same time slot. Time continuity means that the same frequency channel is allocated to the same virtual base station consecutively in time. Spatial continuity means that the same frequency channels are allocated spatially consecutively in the same time slot. This aims to improve the band acquisition rate, frequency continuity, time continuity, and spatial continuity of the shared frequency band in the allocation of the shared frequency band.

In the objective function of equation (2) above, the combination of virtual base stations (c, d) is a combination of virtual base stations in which the amount of interference between the virtual base stations is greater than or equal to the threshold value.

In the objective function of equation (2) above, α_1 is a weighting coefficient of the band acquisition rate term. α_2 is a weighting coefficient of the frequency continuity value term. α_3 is a weighting coefficient of the term of time continuity value. α_4 is a weighting coefficient of the spatial continuity value term. Each term of band acquisition rate, time continuity value, and frequency continuity value is a positive value.

On the other hand, the spatial continuity value term is a negative value. This is the same for the combination of virtual base stations (c, d) because the combination of virtual base stations (c, d) is a combination of virtual base stations where the amount of interference between virtual base stations is greater than the threshold. This is because if the same frequency channel is allocated in time slots, spatial continuity will be reduced.

The weight vector α of the objective function in the above equation (2) “α=(α_1, α_2, α_3, α_4)” is set in advance. Note that the weight vector α of the objective function in equation (2) above, “α=(α_1, α_2, α_3, α_4)”, changes as the number of base stations included in the virtual base station and the sum of the bandwidth demands of each base station increases. The values of each weighting coefficient α_1, α_2, α_3, α_4 may be increased or decreased so that allocation to the virtual base station is given higher priority.

Constraint conditions shown in the following equations (3), (4), and (5) are set in advance in the frequency mapping device 1.

The constraint condition of equation (3) is that the bandwidth allocation amount allocated to a certain virtual base station (q) in a certain time slot (t) is limited to all the base stations (n) that constitute the virtual base station (q). The maximum bandwidth demand fd_n (Vfd_max_q, n, t) is equal to or less than the maximum bandwidth demand fd_n (Vfd_max_q, n, t).

The mapping calculation unit 12 executes calculation to obtain a solution "virtual base station allocation result vx_q, f, t" that satisfies the constraint condition of equation (3) and maximizes the objective function of equation (2). Conventional optimization tools and search algorithms for solving optimization problems can be applied to this calculation.

(Step S15) The mapping calculation unit 12 calculates the frequency channel and time slot of the shared frequency band to be allocated to each base station (n) from the virtual base station allocation results vx_q, f, t obtained in step S14. The allocation result x_n, f, t for each base station (n) is expressed by the following equation (4).

The above is the explanation of the mapping calculation method according to this embodiment.

According to this embodiment, when allocating a shared frequency band, by appropriately compressing the number of base stations to be allocated in the allocation calculation (mapping calculation), the time required for the appropriate allocation of the shared frequency band and the allocation calculation is reduced. This has the effect of being able to shorten the time.

According to this embodiment, base station combinations in which the amount of interference between base stations is less than or equal to a threshold are extracted from a plurality of base stations requesting a shared frequency band as base station combinations to be set as virtual base stations. Therefore, the same frequency channel can be assigned in the same time slot to each base station configuring one virtual base station. Thereby, the same frequency channel can be allocated in the same time slot to a plurality of base stations included in one virtual base station based on the allocation result in units of virtual base stations. This has the effect of suppressing a decrease in frequency usage efficiency caused by overhead due to base station virtualization, which reduces the number of base stations to reduce the calculation time required for frequency mapping processing.

Furthermore, in extracting base station combinations to be set as virtual base stations, base station combinations in which the amount of interference between base stations is less than or equal to a threshold are extracted in order of decreasing bandwidth demand difference between base stations. As a result, since multiple base stations included in one virtual base station have similar bandwidth demands, it is possible to easily maintain fairness in bandwidth allocation by allocating equal bandwidth to each base station. . In addition, if there is a large difference in bandwidth demand between base stations that make up a virtual base station, each base station will have an excess or deficiency in the bandwidth allocated to the virtual base station. Although waste is likely to occur, according to this embodiment, such waste can be suppressed.

Furthermore, as this can improve the overall service quality of wireless networks, for example, goal 9 of the Sustainable Development Goals (SDGs) led by the United Nations, ``Developing resilient infrastructure and achieving sustainable It will be possible to contribute to "promoting industrialization and expanding innovation."

Note that the objective function used in the mapping calculation is not limited to the above-mentioned equation (2). As an objective function, for example, indicators such as the band acquisition rate of the shared frequency band, frequency continuity, time continuity, spatial continuity, etc., and other indicators (for example, throughput of the secondary carrier system, etc.) , at least one of them may be considered.

Further, the amount of interference may be determined based on the distance between base stations, and if the distance is a certain distance or more, it may be determined that the amount of interference is less than a threshold value.

Although the embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like may be made without departing from the gist of the present invention.

Further, a computer program for realizing the functions of each device described above may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed. Note that the "computer system" here may include hardware such as an OS and peripheral devices.
Furthermore, "computer-readable recording media" refers to flexible disks, magneto-optical disks, ROMs, writable non-volatile memories such as flash memory, portable media such as DVDs (Digital Versatile Discs), and media built into computer systems. A storage device such as a hard disk.

Furthermore, "computer-readable recording medium" refers to volatile memory (for example, DRAM (Dynamic It also includes those that retain programs for a certain period of time, such as Random Access Memory).
Further, the program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in a transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
Moreover, the above-mentioned program may be for realizing a part of the above-mentioned functions. Furthermore, it may be a so-called difference file (difference program) that can realize the above-described functions in combination with a program already recorded in the computer system.

DESCRIPTION OF SYMBOLS 1... Frequency mapping device, 11... Information input unit, 12... Mapping calculation unit, 13... Allocation result output unit, 14... Allocation result database (allocation result DB), 20... Virtual base station setting unit

Claims (8)

an information input unit that receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
A virtual base station that extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and sets the extracted base station combinations and other remaining base stations as virtual base stations, respectively. Setting section and
A mapping calculation is performed to allocate a frequency channel and a time slot of the shared frequency band to each of the virtual base stations, and from the result of the mapping calculation, a frequency channel and a time slot of the shared frequency band to be allocated to each of the base stations are calculated. A mapping calculation unit to obtain,
an allocation result output unit that outputs allocation result information indicating the result of allocation of frequency channels and time slots of the shared frequency band allocated to each of the base stations;
Equipped with
The virtual base station setting unit adjusts the number of virtual base stations by increasing the interference amount threshold stepwise.
Frequency mapping device. an information input unit that receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
A virtual base station that extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and sets the extracted base station combinations and other remaining base stations as virtual base stations, respectively. Setting section and
A mapping calculation is performed to allocate a frequency channel and a time slot of the shared frequency band to each of the virtual base stations, and from the result of the mapping calculation, a frequency channel and a time slot of the shared frequency band to be allocated to each of the base stations are calculated. A mapping calculation unit to obtain,
an allocation result output unit that outputs allocation result information indicating the result of allocation of frequency channels and time slots of the shared frequency band allocated to each of the base stations;
Equipped with
The mapping calculation unit uses an objective function to calculate the sum of the band acquisition rate, frequency continuity value, time continuity value, and spatial continuity value of the shared frequency band of each virtual base station during the mapping calculation period. , find a frequency channel of the shared frequency band to be allocated to each virtual base station in each time slot so that the value of the objective function is maximized;
Frequency mapping device. The virtual base station setting unit extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations in order of decreasing bandwidth demand difference between base stations, and sets the combinations as virtual base stations.
The frequency mapping device according to claim 1 or 2 . The virtual base station setting unit extracts combinations in which the amount of interference between the virtual base station and other remaining base stations and between virtual base stations is below a threshold value in order of decreasing bandwidth demand difference, and further sets the combinations as virtual base stations. station,
The frequency mapping device according to claim 3 . an information input step in which the frequency mapping device receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
The frequency mapping device extracts base station combinations in which the amount of interference between base stations is below a threshold value from the plurality of base stations, and converts the extracted base station combinations and other remaining base stations into virtual base stations, respectively. a virtual base station setting step to set the
The frequency mapping device executes mapping calculation to allocate frequency channels and time slots of the shared frequency band to each of the virtual base stations, and based on the result of the mapping calculation, calculates the frequency channel and time slot of the shared frequency band to be allocated to each of the base stations. a mapping calculation step for determining frequency channels and time slots;
an allocation result output step in which the frequency mapping device outputs allocation result information indicating an allocation result of frequency channels and time slots of the shared frequency band allocated to each of the base stations;
including;
The virtual base station setting step adjusts the number of virtual base stations by increasing the interference amount threshold step by step.
Frequency mapping method. an information input step in which the frequency mapping device receives input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
The frequency mapping device extracts base station combinations in which the amount of interference between base stations is below a threshold value from the plurality of base stations, and converts the extracted base station combinations and other remaining base stations into virtual base stations, respectively. a virtual base station setting step to set the
The frequency mapping device executes mapping calculation to allocate frequency channels and time slots of the shared frequency band to each of the virtual base stations, and based on the result of the mapping calculation, calculates the frequency channel and time slot of the shared frequency band to be allocated to each of the base stations. a mapping calculation step for determining frequency channels and time slots;
an allocation result output step in which the frequency mapping device outputs allocation result information indicating an allocation result of frequency channels and time slots of the shared frequency band allocated to each of the base stations;
including;
The mapping calculation step uses an objective function to obtain the sum of the band acquisition rate, frequency continuity value, time continuity value, and spatial continuity value of the shared frequency band of each virtual base station during the mapping calculation period. , find a frequency channel of the shared frequency band to be allocated to each virtual base station in each time slot so that the value of the objective function is maximized;
Frequency mapping method. to the computer,
an information input step of accepting input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
A virtual base station that extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and sets the extracted base station combinations and other remaining base stations as virtual base stations, respectively. configuration steps,
A mapping calculation is performed to allocate a frequency channel and a time slot of the shared frequency band to each of the virtual base stations, and from the result of the mapping calculation, a frequency channel and a time slot of the shared frequency band to be allocated to each of the base stations are calculated. Mapping calculation step to seek;
an assignment result output step of outputting assignment result information indicating the assignment results of frequency channels and time slots of the shared frequency band assigned to each of the base stations;
A computer program for executing
The virtual base station setting step adjusts the number of virtual base stations by increasing the interference amount threshold step by step.
computer program. to the computer,
an information input step of accepting input of information on a plurality of base stations requesting a shared frequency band shared by a plurality of wireless communication systems and information on vacant resources of the shared frequency band;
A virtual base station that extracts base station combinations in which the amount of interference between base stations is less than a threshold value from the plurality of base stations, and sets the extracted base station combinations and other remaining base stations as virtual base stations, respectively. configuration steps,
A mapping calculation is performed to allocate a frequency channel and a time slot of the shared frequency band to each of the virtual base stations, and from the result of the mapping calculation, a frequency channel and a time slot of the shared frequency band to be allocated to each of the base stations are calculated. Mapping calculation step to seek;
an assignment result output step of outputting assignment result information indicating the assignment results of frequency channels and time slots of the shared frequency band assigned to each of the base stations;
A computer program for executing
The mapping calculation step uses an objective function to obtain the sum of the band acquisition rate, frequency continuity value, time continuity value, and spatial continuity value of the shared frequency band of each virtual base station during the mapping calculation period. , find a frequency channel of the shared frequency band to be allocated to each virtual base station in each time slot so that the value of the objective function is maximized;
computer program.

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