WO2018198305A1 - Wireless communication system, connection method, service area construction apparatus, and service area construction program - Google Patents

Abstract

In a wireless network (101), when a wireless terminal (200) which is performing wireless communication by being connected to a certain cell via a base station (300) moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal (200) is switched to the cell to which the wireless terminal (200) moves. A service area construction apparatus (400) constructs, for the wireless network (101), two service areas consisting of a non-virtual cell area and a virtual cell area which overlap each other. The non-virtual cell area is a service area where adjacent cells use different frequencies for wireless communication. The virtual cell area is a service area where adjacent cells use the same frequency for wireless communication. The service area construction apparatus (400) selects or switches a service area to accommodate the wireless terminal (200), according to the type or movement amount of the wireless terminal (200).

Description

Wireless communication system, connection method, service area construction apparatus, and service area construction program

The present invention relates to a wireless communication system, a connection method, a service area construction device, and a service area construction program.

There are mainly 2.4 GHz band and 5 GHz band in the frequency band that can be used in the wireless LAN system. “LAN” is an abbreviation for Local Area Network. “GHz” is an abbreviation for Gigahertz. Services using the 2.4 GHz band are congested due to increased usage. For this reason, efforts are being made to move to the 5 GHz band, which has fewer current users than the 2.4 GHz band. For example, IEEE 802.11ac, the latest wireless LAN standard that has been standardized, is a standard defined only in the 5 GHz band.

As a wireless LAN base station, a base station having a dual configuration capable of simultaneous communication in the 2.4 GHz band and the 5 GHz band is the mainstream. However, recently, wireless LAN base stations capable of simultaneous communication in two 5 GHz bands have appeared in addition to simultaneous communication in the 2.4 GHz band and the 5 GHz band with one base station. Therefore, it is possible to simultaneously provide services using a plurality of frequency bands at the same place while supporting the shift to the 5 GHz band.

A wide variety of terminals such as notebook PCs, tablets, smartphones, and wireless IP phones have appeared as wireless terminals connected to base stations. “PC” is an abbreviation for Personal Computer. “IP” is an abbreviation for Internet Protocol. There is a need to construct a wireless LAN system capable of efficiently accommodating various types of wireless terminals in a service area using a plurality of frequency bands and providing services.

In a general wireless LAN system, a frequency is assigned to each base station so that non-virtual cells, which are cells having different frequencies, are adjacent to each other. For example, assume that four frequencies f1, f2, f3, and f4 shown in FIG. 17 can be used. In this case, as shown in FIG. 18, four frequencies f1, f2, f3, and f4 are allocated to each base station, and a non-virtual cell area that is a service area configured such that frequencies do not overlap between adjacent cells. Can be built. In the example of FIG. 18, four non-virtual cell areas are constructed.

In the wireless LAN system described in Patent Document 1, frequencies are allocated to each base station so that virtual cells that are used in common and have effective access control by CSMA / CA are adjacent to each other. “CSMA / CA” is an abbreviation for Carrier Sense Multiple Access with Collation Avoidance. For example, assume that four frequencies f1, f2, f3, and f4 shown in FIG. 17 can be used. In this case, as shown in FIG. 19, four frequencies f1, f2, f3, and f4 are assigned to each base station, and the frequencies are common within the same service area, but the frequencies do not overlap between adjacent service areas. It is possible to construct a virtual cell area which is a service area configured as described above. In the example of FIG. 19, four virtual cell areas are constructed.

JP 2007-166411 A

When constructing a non-virtual cell area, since the arrangement of cells having different frequencies is denser than when constructing a virtual cell area, the system throughput is improved. However, there is a possibility that the handover accompanying the movement of the wireless terminal frequently occurs and the communication is interrupted or the communication becomes unstable. On the other hand, when constructing a virtual cell area, since the area of the same frequency is wider than when constructing a non-virtual cell area, the frequency of handover accompanying movement of the wireless terminal is reduced. However, since an access control operation using the CSMA / CA collision avoidance function is required in the virtual cell area, the system throughput may be reduced.

As described above, in the prior art, it is necessary to construct a service area by a trade-off between adopting a non-virtual cell area to give priority to throughput or adopting a virtual cell area to reduce the frequency of handover. . Therefore, in an environment where there are a wide variety of wireless terminals of different types and movement amounts, it is likely that the constructed service area is suitable for only some terminals and not suitable for the remaining terminals. .

An object of the present invention is to enable a wide variety of wireless terminals to use a service area suitable for each terminal.

A wireless communication system according to an aspect of the present invention includes:
When a wireless terminal connected to a cell and performing wireless communication via a base station moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal becomes the movement destination cell of the wireless terminal In a switching wireless communication system,
The non-virtual cell area, which is a service area where the frequency used for the wireless communication in the cells adjacent to each other is different, and the frequency used for the wireless communication in the cell adjacent to each other are common and overlap with the non-virtual cell area. In order to construct a virtual cell area which is a service area, a frequency used in each cell in the non-virtual cell area and a frequency used in each cell in the virtual cell area are set in the base station A frequency control unit,
A connection control unit that connects the wireless terminal to a cell selected from a cell in the non-virtual cell area and a cell in the virtual cell area that overlap each other.

In the present invention, a wireless terminal is connected to a cell selected from a cell in a non-virtual cell area and a cell in a virtual cell area that overlap each other. Therefore, a wide variety of wireless terminals can use a service area suitable for each terminal.

1 is a block diagram showing a configuration of a radio communication system according to Embodiment 1. FIG. 1 is a block diagram illustrating an example of a configuration of a wireless communication system according to a first embodiment. FIG. 3 is a distribution diagram illustrating an example of frequencies used in the wireless communication system according to the first embodiment. FIG. 3 is a diagram showing an example of a service area constructed in the wireless communication system according to the first embodiment. FIG. 3 is a diagram showing an example of a service area constructed in the wireless communication system according to the first embodiment. FIG. 2 is a block diagram showing a configuration of a service area construction device according to the first embodiment. 4 is a flowchart showing the operation of the service area construction device according to the first embodiment. 10 is a flowchart showing the operation of the service area construction device according to the second embodiment. The table | surface which shows the example of the processing result of the service area construction apparatus which concerns on Embodiment 2. FIG. FIG. 9 is a block diagram showing a configuration of a service area construction device according to a third embodiment. 10 is a flowchart showing the operation of the service area construction device according to the third embodiment. FIG. 10 is a diagram illustrating an example of a service area constructed in the wireless communication system according to the third embodiment. FIG. 10 is a diagram illustrating an example of a service area constructed in the wireless communication system according to the third embodiment. FIG. 6 is a block diagram showing a configuration of a service area construction device according to a fourth embodiment. FIG. 9 is a block diagram illustrating a configuration of a wireless terminal according to a fourth embodiment. 10 is a flowchart showing an operation of a wireless terminal according to the fourth embodiment. The distribution map which shows the example of the frequency used with a wireless LAN system. The figure which shows the example of a non-virtual cell area. The figure which shows the example of a virtual cell area.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals. In the description of the embodiments, the description of the same or corresponding parts will be omitted or simplified as appropriate. The present invention is not limited to the embodiments described below, and various modifications can be made as necessary. For example, two or more embodiments among the embodiments described below may be combined and executed. Alternatively, among the embodiments described below, one embodiment or a combination of two or more embodiments may be partially implemented.

Embodiment 1 FIG.
This embodiment will be described with reference to FIGS.

*** Explanation of configuration ***
The configuration of radio communication system 100 according to the present embodiment will be described with reference to FIG. 1 and FIG.

The radio communication system 100 includes a radio terminal 200, a base station 300, and a service area construction device 400 that is an apparatus independent of the radio terminal 200 and the base station 300.

The wireless terminal 200 and the base station 300 constitute a wireless network 101.

When the wireless terminal 200 connected to a certain cell and performing wireless communication via the base station 300 moves to an adjacent cell in the same service area, the wireless network 101 wirelessly connects the cell to which the wireless terminal 200 is connected. This is a network that switches to the cell to which the terminal 200 is moving.

In this embodiment, a dual service area of a non-virtual cell area and a virtual cell area is constructed using the dual configuration of the radio function of the base station 300. That is, two service areas of a non-virtual cell area and a virtual cell area that overlap each other are constructed for the wireless network 101. The non-virtual cell area is a service area in which frequencies used for wireless communication are different between cells adjacent to each other. The virtual cell area is a service area in which frequencies used for wireless communication are common to cells adjacent to each other.

Note that if the base station 300 supports more frequency bands than the dual configuration, triple or more service areas may be constructed. That is, the wireless network 101 includes two or more non-virtual cell areas and one or more virtual cell areas, or one or more non-virtual cell areas and two or more virtual cell areas. In addition, three or more service areas that overlap each other may be constructed.

Although not essential, when the wireless terminal 200 moves between adjacent service areas, the wireless network 101 changes the connection destination cell of the wireless terminal 200 from the cell in the service area of the wireless terminal 200 to the wireless terminal 200. It is also a network that switches to a cell in the service area of 200 destinations.

The wireless network 101 is a wireless LAN in the present embodiment, but may be any network as long as it can switch the connection destination cell of the wireless terminal 200 as the wireless terminal 200 moves as described above.

The service area construction device 400 is connected to a plurality of base stations 300, manages information related to the arrangement of each base station 300, and performs frequency control of each base station 300. The base station 300 includes radio units 301 and 302 having a dual configuration, and forms a double cell of a non-virtual cell and a virtual cell. The service area construction device 400 sets the frequency used in the non-virtual cell in the radio unit 301 of each base station 300, and sets the frequency used in the virtual cell in the radio unit 302 of each base station 300. One or more wireless terminals 200 are arranged in a cell formed by each base station 300. The service area construction device 400 collects information on the type and connection status of the wireless terminal 200 connected to each base station 300 from each base station 300. The service area construction device 400 selects or switches a service area in which the wireless terminal 200 is accommodated according to the type or movement amount of the wireless terminal 200.

For example, assume that two sets of four frequencies f1, f2, f3 and f4 shown in FIG. 3 and another four frequencies f5, f6, f7 and f8 can be used. In this case, as shown in FIG. 4 and FIG. 5, the service area construction device 400 constructs a non-virtual cell area by allocating four frequencies f1, f2, f3 and f4 to each base station 300, and another 4 Two frequencies f5, f6, f7, and f8 are allocated to each base station 300, and a virtual cell area is built on a non-virtual cell area. The non-virtual cell area is configured so that frequencies do not overlap between adjacent cells. The virtual cell area has a common frequency within the same service area, but is configured such that the frequencies do not overlap between adjacent service areas. In the example of FIG. 4, four non-virtual cell areas and four virtual cell areas are constructed. One non-virtual cell area and a virtual cell area overlapping the non-virtual cell area are formed by four base stations 300. In the example of FIGS. 2 and 5, four base stations 300 of BS 1, BS 2, BS 3 and BS 4 are assigned frequencies f 1, f 2, f 3 and f 4 for non-virtual cells, respectively, and formed by these four base stations 300. SSID “A” is assigned to the non-virtual cell area. Further, the virtual cell frequency f5 is commonly assigned to the four base stations 300 of BS1, BS2, BS3, and BS4, and the SSID “B” is assigned to the virtual cell area formed by these four base stations 300. ing. “SSID” is an abbreviation for Service Set Identifier.

Referring to FIG. 6, the configuration of service area construction apparatus 400 according to the present embodiment will be described.

The service area construction device 400 is a computer. The service area construction device 400 includes a processor 401 and other hardware such as a memory 402, an input interface 403, and an output interface 404. The processor 401 is connected to other hardware via a signal line, and controls these other hardware.

The service area construction device 400 includes a base station monitoring control unit 410 and a terminal monitoring control unit 420 as functional elements. The functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420 are realized by software. The base station monitoring control unit 410 includes an arrangement management unit 411 and a frequency control unit 412. The terminal monitoring control unit 420 includes an information management unit 421, a movement amount measurement unit 422, a movement amount determination unit 423, and a connection control unit 424.

The processor 401 is a device that executes a service area construction program. The service area construction program is a program that realizes the functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420. The processor 401 is, for example, a CPU. “CPU” is an abbreviation for Central Processing Unit.

The memory 402 is a device that stores a service area construction program. The memory 402 is, for example, a flash memory or a RAM. “RAM” is an abbreviation for Random Access Memory.

The memory 402 stores arrangement information 431 and frequency information 432 of each base station 300, type information 441, connection information 442, movement amount information 443, and movement determination information 444 of each wireless terminal 200.

The input interface 403 is at least one of a receiver that receives information from each base station 300 via the monitoring control network and a port to which an input device operated by an operator for inputting information is connected. Although not shown, the monitoring control network is, for example, a wired LAN. The input device is, for example, a mouse, a keyboard, or a touch panel.

The output interface 404 is at least one of a transmitter that transmits information to each base station 300 via the monitoring control network and a port to which a display that displays information on the screen is connected. Although not shown, the display is, for example, an LCD. “LCD” is an abbreviation for Liquid Crystal Display.

The service area construction program is read into the processor 401 and executed by the processor 401. The memory 402 stores not only the service area construction program but also the OS. “OS” is an abbreviation for Operating System. The processor 401 executes the service area construction program while executing the OS.

The service area construction program and the OS may be stored in the auxiliary storage device. The auxiliary storage device is, for example, a flash memory or an HDD. “HDD” is an abbreviation for Hard Disk Drive. The service area construction program and the OS stored in the auxiliary storage device are loaded into the memory 402 and executed by the processor 401.

Note that part or all of the service area construction program may be incorporated in the OS.

The service area construction device 400 may include a plurality of processors that replace the processor 401. The plurality of processors share the execution of the service area construction program. Each processor, like the processor 401, is a device that executes a service area construction program.

Data, information, signal values and variable values used, processed or output by the service area construction program are stored in the memory 402, the auxiliary storage device, or a register or cache memory in the processor 401.

In the service area construction program, the base station monitoring control unit 410 and the terminal monitoring control unit 420 have the respective units replaced by “processing”, or the base station monitoring control unit 410 and the terminal monitoring control unit 420 It is a program that causes a computer to execute each procedure obtained by replacing “part” of each unit with “procedure”. The service area construction program may be provided by being recorded on a computer-readable medium, or may be provided as a program product.

*** Explanation of operation ***
With reference to FIG. 7, the operation of service area construction apparatus 400 according to the present embodiment will be described. This operation corresponds to the service area construction method and connection method according to the present embodiment.

In step S11, the arrangement management unit 411 manages the arrangement information 431 of each base station 300 arranged so that wireless LAN communication is possible at a desired location such as an office. Specifically, the arrangement management unit 411 stores arrangement information 431 input from each base station 300 or an operator via the input interface 403 in the memory 402. The arrangement information 431 is information indicating the position of each base station 300 such as the latitude and longitude of each base station 300.

In step S12, the frequency control unit 412 sets the frequency used in each cell in the non-virtual cell area in each base station 300 in order to construct the non-virtual cell area. Only one non-virtual cell area may be constructed, but in the present embodiment, at least two non-virtual cell areas are constructed. Therefore, the frequency control unit 412 sets the frequency used in each cell in each non-virtual cell area in each base station 300 in order to construct at least two non-virtual cell areas. Specifically, the frequency control unit 412 determines the frequency used by the radio unit 301 among the two radio units 301 and 302 included in each base station 300 based on the arrangement information 431 of each base station 300. It determines so that it may become a frequency different from the frequency of an adjacent cell. The frequency control unit 412 sets the determined frequency in the radio unit 301 of each base station 300 via the output interface 404. The cell corresponding to the radio unit 301 is a non-virtual cell. The frequency control unit 412 allocates a non-virtual cell SSID to the radio unit 301 of each base station 300 via the output interface 404. 2 and 5, the frequency control unit 412 sets the frequencies f1, f2, f3, and f4 in the radio units 301 of the four base stations 300 of BS1, BS2, BS3, and BS4, respectively. The SSID “A” is commonly assigned to the non-virtual cells of the station 300. Similarly, the frequency control unit 412 sets the frequencies f1, f2, f3, or f4 in the radio units 301 of the other base stations 300 from BS5 to BSx, and sets the SSID “C” in the non-virtual cells of these other base stations 300. ”,“ E ”or“ G ”. Note that the same SSID “A” may be assigned to the non-virtual cells of these other base stations 300.

In step S13, the frequency control unit 412 sets the frequency used in each cell in the virtual cell area in each base station 300 in order to construct the virtual cell area. Although only one virtual cell area may be constructed, in the present embodiment, at least two virtual cell areas having different frequencies used for wireless communication are constructed in virtual cell areas adjacent to each other. Therefore, the frequency control unit 412 sets the frequency used in each cell in each virtual cell area in each base station 300 in order to construct such at least two virtual cell areas. Specifically, the frequency control unit 412 determines, based on the arrangement information 431 of each base station 300, the frequency used by the radio unit 302 among the two radio units 301 and 302 included in each base station 300. It determines so that it may become the same frequency as the frequency of an adjacent cell. The frequency control unit 412 sets the determined frequency in the radio unit 302 of each base station 300 via the output interface 404. The cell corresponding to the radio unit 302 is a virtual cell. The frequency control unit 412 allocates the virtual cell SSID to the radio unit 302 of each base station 300 via the output interface 404. In the example of FIG. 2 and FIG. 5, the frequency control unit 412 sets the frequency f5 in common to the radio units 302 of the four base stations 300 of BS1, BS2, BS3, and BS4, and the virtual cells of these four base stations 300 SSID “B” is assigned in common. Similarly, the frequency control unit 412 sets the frequencies f6, f7, or f8 in the radio units 301 of the other base stations 300 from BS5 to BSx, and sets the SSID “D”, “ Assign "F" or "H". The same SSID “B” may be assigned to the virtual cells of these other base stations 300.

The frequency control unit 412 is information indicating the frequencies set in the two radio units 301 and 302 of each base station 300 in step S12 and step S13 and the SSID assigned to the two radio units 301 and 302 of each base station 300. Is generated as frequency information 432 and the frequency information 432 of each base station 300 is stored in the memory 402.

In step S14, the connection control unit 424 connects each wireless terminal 200 to a cell selected from the cells in the non-virtual cell area and the cell in the virtual cell area, which overlap each other. In the present embodiment, connection control section 424 determines each radio terminal 200 from among the cells in the non-virtual cell area and the cells in the virtual cell area that overlap each other according to the type of each radio terminal 200. Select the cell to connect to. The connection control unit 424 connects each wireless terminal 200 to the selected cell. Specifically, the connection control unit 424 connects the wireless terminal 200 such as a notebook PC, which is assumed to have a small movement amount, to a cell in the non-virtual cell area based on the type information 441 of each wireless terminal 200. Then, the wireless terminal 200 that is assumed to have a large movement amount, such as a tablet, a smartphone, and a wireless IP phone, is connected to the cell in the virtual cell area. The type information 441 is information indicating the type of each wireless terminal 200. The information management unit 421 stores in advance in the memory 402 the type information 441 of each wireless terminal 200 input from each base station 300 or operator via the input interface 403. In the example of FIG. 2 and FIG. 5, WT 1 exists in the non-virtual cell and the virtual cell of BS 2 as one wireless terminal 200. Assuming that WT1 is requesting connection to BS2, if WT1 is a notebook PC, WT1 connects WT1 to a non-virtual cell of BS2, and WT1 is a tablet, smartphone or wireless IP phone. If there is, connect WT1 to the virtual cell of BS2. When connected to the non-virtual cell of BS2, WT1 performs radio communication using frequency f2. On the other hand, when connected to the virtual cell of BS2, WT1 performs radio communication using frequency f5. Although any method can be used as a method for the connection control unit 424 to control the connection of the radio terminal 200, in this embodiment, the connection control unit 424 connects the radio terminal 200 via the base station 300. A method is used in which a request is received and the SSID of a cell that is permitted to be connected is returned via the base station 300 in response to the request. In the above example, connection control unit 424 notifies WT1 of SSID “A” if WT1 is a notebook PC, and notifies WT1 of SSID “B” if WT1 is a tablet, smartphone, or wireless IP phone. To do.

The connection control unit 424 generates, as connection information 442, information indicating the SSID of the cell connected to each wireless terminal 200 in step S14, and stores the connection information 442 of each wireless terminal 200 in the memory 402.

As described above, the service area construction device 400 constructs a double service area of a non-virtual cell area and a virtual cell area, and then assigns each wireless terminal 200 to a non-virtual cell area and a virtual depending on the type of each wireless terminal 200. It is housed in one of the cell areas.

In step S15, the movement amount measuring unit 422 periodically measures the movement amount of each wireless terminal 200 connected in step S14. Specifically, the movement amount measurement unit 422 monitors the change in the position of each wireless terminal 200 and measures the movement amount of each wireless terminal 200. Although any method can be used as a method for the movement amount measurement unit 422 to monitor the change in the position of the wireless terminal 200, in this embodiment, the movement amount measurement unit 422 transmits the base station 300 from the wireless terminal 200. A method is used in which the position information is periodically received via the position information, and the change amount of the position specified from the position information received within the latest fixed period is calculated. The position change amount calculated by this method is regarded as the movement amount of the wireless terminal 200 or is converted into the movement amount of the wireless terminal 200 using an arbitrary expression.

The movement amount measurement unit 422 generates information indicating the movement amount of each wireless terminal 200 measured in step S15 as movement amount information 443, and stores the movement amount information 443 of each wireless terminal 200 in the memory 402. The movement amount information 443 is referred to by the movement amount determination unit 423 in step S16.

In step S16, the movement amount determination unit 423 determines the amount of movement of each wireless terminal 200 measured in step S15. Specifically, the movement amount determination unit 423 compares the movement amount measured by the movement amount measurement unit 422 with a threshold value. If the movement amount is less than the threshold value, the process of step S17 is performed. If the movement amount is greater than or equal to the threshold value, the process of step S18 is performed.

The movement amount determination unit 423 generates information indicating the determination result of step S16 as movement determination information 444, and stores the movement determination information 444 of each wireless terminal 200 in the memory 402. The movement determination information 444 is referred to by the connection control unit 424 in order to determine which process of step S17 and step S18 is to be performed.

In step S17 and step S18, the connection control unit 424 determines that each wireless terminal is connected between the cells in the non-virtual cell area and the cells in the virtual cell area that overlap each other according to the movement amount of each wireless terminal 200. Switch the 200 connected cells. Specifically, when a certain wireless terminal 200 is connected to a cell in the virtual cell area and the movement amount of the wireless terminal 200 becomes smaller than the threshold value, in step S17, the connection control unit 424 The connection destination cell of the wireless terminal 200 is switched to a cell in the non-virtual cell area that overlaps with the cell to which the wireless terminal 200 is connected. On the other hand, if the movement amount of the wireless terminal 200 is not smaller than the threshold value, the connection control unit 424 does not switch the connection destination cell of the wireless terminal 200 in step S18. That is, the connection control unit 424 maintains the connection to the cell in the virtual cell area of the wireless terminal 200. When a certain mobile station 200 is connected to a cell in the non-virtual cell area and the movement amount of the mobile station 200 is larger than the threshold, the connection control unit 424 determines that the wireless control terminal 424 determines that the wireless control terminal 424 is not connected to the wireless terminal 200 in step S18. The cell to which the terminal 200 is connected is switched to a cell in the virtual cell area that overlaps the cell to which the wireless terminal 200 is connected. In the present embodiment, even when the movement amount of the wireless terminal 200 becomes the same as the threshold value, in step S18, the connection control unit 424 connects the connection destination cell of the wireless terminal 200 to the wireless terminal 200. Switch to a cell in the virtual cell area that overlaps the current cell. On the other hand, if the movement amount of the wireless terminal 200 is smaller than the threshold value, the connection control unit 424 does not switch the connection destination cell of the wireless terminal 200 in step S17. That is, the connection control unit 424 maintains the connection of the wireless terminal 200 to a cell in the non-virtual cell area. In the example of FIG. 2 and FIG. 5, even if WT1 is a notebook PC, connection control unit 424 disconnects WT1 from a non-virtual cell and makes WT1 virtual if the amount of change in the position of WT1 is large. Connect to the cell. In addition, even if WT1 is a tablet, a smartphone, or a wireless IP phone, connection control unit 424 disconnects WT1 from the virtual cell and changes WT1 to a non-virtual cell if the amount of change in the position of WT1 is small. Connecting. The method by which the connection control unit 424 controls the connection of the wireless terminal 200 is as described above. In the above example, when switching the connection destination cell of WT1, the connection control unit 424 notifies the WT1 of the SSID of the switching destination cell.

As described above, the service area construction apparatus 400 periodically measures the movement amount of each wireless terminal 200 after accommodating each wireless terminal 200 in either the non-virtual cell area or the virtual cell area, The accommodation destination of each wireless terminal 200 is changed depending on the determination result.

In step S19, the information management unit 421 updates the connection information 442 of each wireless terminal 200 stored in the memory 402 as necessary. Specifically, when the connection destination cell of any wireless terminal 200 is switched in step S17 or step S18, the information management unit 421 displays the connection information 442 of the wireless terminal 200 as the wireless terminal 200. Update to information indicating the SSID of the connected cell.

After step S19, step S15 is performed again.

Note that the balance between the number of radio terminals 200 accommodated in the non-virtual cell area and the number of radio terminals 200 accommodated in the virtual cell area may be adjusted by changing the threshold used in step S16.

*** Explanation of the effect of the embodiment ***
In the present embodiment, radio terminal 200 is connected to a cell selected from a cell in a non-virtual cell area and a cell in a virtual cell area that overlap each other. Therefore, a wide variety of wireless terminals 200 can use service areas suitable for each terminal.

In the present embodiment, the wireless LAN service area has a double configuration of an area composed of non-virtual cells and an area composed of virtual cells. That is, when a plurality of base stations 300 are arranged in a plane and a wireless communication service area is constructed by a cell in which an access control method to which a collision avoidance function is added is effective, cells having the same frequency are adjacent to each other. A double service area is constructed of the virtual cell area and a non-virtual cell area in which cells having different frequencies are adjacent to each other. An optimal service area is selected for each wireless terminal 200 according to the type or movement amount of the wireless terminal 200. It is also possible to switch the service area where the wireless terminal 200 is accommodated as necessary. Therefore, the throughput can be improved for the radio terminal 200 with a small movement amount. For the radio terminal 200 with a large amount of movement, it is possible to reduce the frequency of handovers to make it difficult for communication interruptions to occur and to stabilize communication.

*** Other configurations ***
In the present embodiment, the functions of base station monitoring control section 410 and terminal monitoring control section 420 are realized by software. However, as a modification, the functions of base station monitoring control section 410 and terminal monitoring control section 420 are software and hardware. It may be realized by combination with wear. That is, part of the functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420 may be realized by dedicated hardware, and the rest may be realized by software.

The dedicated hardware is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, a logic IC, a GA, an FPGA, or an ASIC. “GA” is an abbreviation for Gate Array. “FPGA” is an abbreviation for Field-Programmable Gate Array. “ASIC” is an abbreviation for Application Specific Integrated Circuit.

Both the processor 401 and the dedicated hardware are processing circuits. That is, regardless of whether the functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420 are realized by software or a combination of software and hardware, the base station monitoring control unit 410 and the terminal monitoring control The function of the unit 420 is realized by a processing circuit.

In the present embodiment, radio communication system 100 has service area construction device 400 that is an independent device from radio terminal 200 and base station 300. However, as a modification, service area construction device 400 has any base. It may be integrated into the station 300. Alternatively, functions equivalent to the service area construction device 400 may be distributed and implemented in each base station 300.

Embodiment 2. FIG.
In the present embodiment, differences from the first embodiment will be mainly described with reference to FIGS.

In this embodiment, the service area construction device 400 measures the amount of movement of each wireless terminal 200 from the information of the base station 300 to which each wireless terminal 200 is connected, and determines the amount of movement.

*** Explanation of configuration ***
Since the configuration of radio communication system 100 according to the present embodiment is the same as the configuration of radio communication system 100 according to Embodiment 1, the description thereof is omitted.

*** Explanation of operation ***
With reference to FIG. 8, the operation of service area construction apparatus 400 according to the present embodiment will be described. This operation corresponds to the connection method according to the present embodiment.

Also in this embodiment, the processing from step S11 to step S14 shown in FIG. 7 is performed. That is, as in the first embodiment, service area construction apparatus 400 constructs a double service area of a non-virtual cell area and a virtual cell area, and then sets each wireless terminal 200 according to the type of each wireless terminal 200. Are accommodated in either the non-virtual cell area or the virtual cell area.

In the present embodiment, processing from step S21 to step S27 is performed instead of the processing from step S15 to step S19 shown in FIG. In the first embodiment, the movement amount measurement unit 422 monitors the change in the position of each wireless terminal 200 and measures the movement amount of each wireless terminal 200. In this embodiment, the movement amount measurement unit 422 The switching of the connection destination of each wireless terminal 200 is monitored, and the movement amount of each wireless terminal 200 is measured.

In step S21, the movement amount measuring unit 422 confirms the base station 300 to which each wireless terminal 200 is connected. The process of step S21 is performed for each preset measurement time. Specifically, the movement amount measurement unit 422 extracts information on the base station 300 to which each wireless terminal 200 is connected from information input from each base station 300 via the input interface 403.

In step S22, if the preset measurement period has not ended, the process of step S21 is performed again. If the measurement period ends, the process of step S23 is performed.

In step S23, the movement amount measurement unit 422 uses, as the connection destination change count, the number of times the base station 300 connected to each wireless terminal 200 is changed within the measurement period from the information acquired in step S21 within the measurement period. calculate.

The movement amount measurement unit 422 generates information indicating the connection destination change count of each wireless terminal 200 calculated in step S23 as movement amount information 443, and stores the movement amount information 443 of each wireless terminal 200 in the memory 402. The movement amount information 443 is referred to by the movement amount determination unit 423 in step S24.

In the example of FIG. 9, the movement amount measurement unit 422 acquires information on the base station 300 to which the three wireless terminals 200 of WT1, WT2, and WT3 are connected during the period from the measurement time t1 to t5, and the connection destination in that period Calculate the number of changes. In this example, the connection destination change count of WT1 is 0, the connection destination change count of WT2 is 1, and the connection destination change count of WT3 is 4.

In step S24, the movement amount determination unit 423 compares the connection destination change count of each wireless terminal 200 calculated in step S23 with a threshold value, and determines the amount of movement of each wireless terminal 200. If the connection destination change count is less than the threshold value, the process of step S25 is performed. If the connection destination change count is greater than or equal to the threshold value, the process of step S26 is performed.

The movement amount determination unit 423 generates information indicating the determination result of step S24 as movement determination information 444, and stores the movement determination information 444 of each wireless terminal 200 in the memory 402. The movement determination information 444 is referred to by the connection control unit 424 in order to determine which process of step S25 and step S26 is to be performed.

In the example of FIG. 9, since the threshold value is 1, the movement amount measurement unit 422 determines that the movement amount is large when the number of connection destination changes within the measurement period is one or more, and the movement amount is small otherwise. Is determined. In this example, it is determined that the movement amount of WT1 is small, the movement amount of WT2 is large, and the movement amount of WT3 is large.

The processing of step S25 and step S26 is the same as the processing of step S17 and step S18 shown in FIG. In the example of FIG. 9, since it is determined that the amount of movement of WT1 that is still connected to the virtual cell of BS2 during the measurement period is small, the connection control unit 424 disconnects the connection of WT1 to the virtual cell and WT1. To the non-virtual cell. In addition, during the measurement period, since it is determined that the amount of movement of WT2 that has been switched once between non-virtual cells is large, the connection control unit 424 disconnects the connection of WT2 to the non-virtual cell and Connect to a virtual cell. On the other hand, during the measurement period, it is determined that the amount of movement of WT 3 that has been switched four times between virtual cells is large, so connection control unit 424 maintains the connection of WT 3 to the virtual cell.

As described above, also in the present embodiment, service area construction apparatus 400 periodically stores the movement amount of each wireless terminal 200 after accommodating each wireless terminal 200 in either the non-virtual cell area or the virtual cell area. Measurement is performed, and the accommodation destination of each wireless terminal 200 is changed according to the determination result of the amount of movement.

The process of step S27 is the same as the process of step S19 shown in FIG.

After step S27, step S21 is performed again.

Note that the balance between the number of radio terminals 200 accommodated in the non-virtual cell area and the number of radio terminals 200 accommodated in the virtual cell area may be adjusted by changing the threshold used in step S24.

*** Explanation of the effect of the embodiment ***
In the present embodiment, the movement amount of each wireless terminal 200 is calculated by monitoring the connection status of each wireless terminal 200 to the base station 300 for a certain period. This eliminates the need to periodically transmit location information from the wireless terminal 200 to the service area construction device 400.

*** Other configurations ***
In the present embodiment, the functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420 are realized by software, as in the first embodiment. However, as in the modification of the first embodiment, The functions of the station monitoring control unit 410 and the terminal monitoring control unit 420 may be realized by a combination of software and hardware.

Embodiment 3 FIG.
In the present embodiment, differences from the first embodiment will be mainly described with reference to FIGS.

In this embodiment, the service area construction device 400 changes the cell configuration of the virtual cell area according to the movement history of each wireless terminal 200, and changes the range of the service area of the same frequency. In the present embodiment, a single or more service area including only the virtual cell area may be constructed. That is, in this embodiment, a non-virtual cell area may not be constructed.

*** Explanation of configuration ***
Unlike the first embodiment, in the present embodiment, when the wireless network 101 moves between service areas adjacent to each other, the wireless terminal 200 changes the connection destination cell of the wireless terminal 200 to the movement source of the wireless terminal 200. The network needs to be switched from a cell in the service area to a cell in the service area to which the wireless terminal 200 is moved.

Referring to FIG. 10, the configuration of service area construction apparatus 400 according to the present embodiment will be described.

The terminal monitoring control unit 420 includes a movement history creation unit 425 in addition to the information management unit 421, the movement amount measurement unit 422, the movement amount determination unit 423, and the connection control unit 424.

*** Explanation of operation ***
With reference to FIG. 11, the operation of service area construction apparatus 400 according to the present embodiment will be described. This operation corresponds to the service area construction method according to the present embodiment.

In this embodiment, the service area construction device 400 constructs a virtual cell area by constructing a double service area of a non-virtual cell area and a virtual cell area and then performing the processing from step S31 to step S37. Correct as appropriate. Specifically, the service area construction device 400 detects the total number and the movement range of the moving wireless terminals 200 from the information of the base station 300 to which each wireless terminal 200 is connected, and determines the virtual cell area based on the detection result. The frequency of the cell to be configured is changed, and the service area range of the same frequency is adaptively changed.

In step S31, the movement amount measuring unit 422 confirms the base station 300 to which each wireless terminal 200 is connected. The process of step S31 is performed for every preset measurement time. Specifically, the movement amount measurement unit 422 extracts information on the base station 300 to which each wireless terminal 200 is connected from information input from each base station 300 via the input interface 403.

In step S32, if the preset measurement period has not ended, the process of step S31 is performed again. If the measurement period ends, the process of step S33 is performed.

In step S33, the movement history creation unit 425 obtains the change history of the base station 300 to which each wireless terminal 200 is connected during the measurement period from the information acquired in step S31 within the measurement period. Create as.

In steps S34 to S36, the frequency control unit 412 changes the combination of cells included in each virtual cell area according to the movement history of each radio terminal 200, and changes the cell combination in each virtual cell area. A frequency to be used is set in the base station 300. That is, the frequency control unit 412 reviews the frequency of the cells constituting each virtual cell area based on the movement history of each wireless terminal 200 created by the movement history creation unit 425. Specifically, in step S34, the frequency control unit 412 calculates the number of handovers of each radio terminal 200 from the movement history of each radio terminal 200 created in step S33. In step S34, the frequency control unit 412 compares the number of handovers of each radio terminal 200 calculated in step S34 with a threshold value. If the number of handovers of wireless terminals 200 that exceed a certain ratio among all the wireless terminals 200 is less than the threshold value, the process of step S31 is performed again. If the number of handovers of wireless terminals 200 exceeding a certain ratio among all the wireless terminals 200 is equal to or greater than the threshold value, the process of step S36 is performed. The threshold value is set to an arbitrary value larger than 0. In step S36, the frequency control unit 412 analyzes the tendency of the movement range of the wireless terminal 200 from the movement history of each wireless terminal 200, and changes the frequency arrangement of each virtual cell area according to the analysis result. The frequency control unit 412 sets the changed frequency in the radio unit 302 of each base station 300 via the output interface 404. The frequency control unit 412 allocates the changed SSID for the virtual cell to the radio unit 302 of each base station 300 via the output interface 404. 12 and 13 represent movement range trends of the wireless terminal 200 by flow lines 501 and 502, respectively. In the example of FIG. 12, since each flow line 501 is within one virtual cell area, the process of step S36 is not performed. That is, the frequency arrangement of each virtual cell area is maintained. On the other hand, in the example of FIG. 13, since each flow line 501 straddles between two or more virtual cell areas, the process of step S36 is performed. That is, the frequency arrangement of each virtual cell area is adjusted so that the moving range of the radio terminal 200 can be covered by one virtual cell area as much as possible.

In step S37, the frequency control unit 412 updates the frequency information 432 of each base station 300 stored in the memory 402. Specifically, when the frequency and SSID of the radio unit 302 of any of the base stations 300 are changed in step S36, the frequency control unit 412 includes the base station 300 included in the frequency information 432 of the base station 300. The information indicating the frequency set in the wireless unit 302 and the SSID assigned to the wireless unit 302 of the base station 300 is updated.

*** Other configurations ***
In the present embodiment, according to the movement history of each radio terminal 200, the frequency of the cells constituting each virtual cell area can be changed so that the number of handovers of each radio terminal 200 is reduced. The tendency of the movement range of the wireless terminal 200 as indicated by the flow lines 501 and 502 in FIGS. 12 and 13 may depend on the office layout or the like. Therefore, it is possible to reduce the number of handovers of the radio terminal 200 by reviewing the frequency arrangement of each virtual cell area according to the analysis result of the movement range trend of the radio terminal 200.

Embodiment 4 FIG.
In the present embodiment, differences from the first embodiment will be mainly described with reference to FIGS.

In the present embodiment, each wireless terminal 200 measures the movement amount of each wireless terminal 200 from the position information of each wireless terminal 200, and the virtual cell area and the non-virtual cell according to the determination result of the movement amount. Switch to the area voluntarily.

*** Explanation of configuration ***
With reference to FIG. 14, the structure of the service area construction apparatus 400 according to the present embodiment will be described.

The terminal monitoring control unit 420 includes an information management unit 421 and a connection control unit 424. In the present embodiment, the movement amount measurement unit 422 and the movement amount determination unit 423 in the first embodiment are not necessary.

The memory 402 stores arrangement information 431 and frequency information 432 of each base station 300, type information 441 and connection information 442 of each wireless terminal 200. In the present embodiment, the movement amount information 443 and the movement determination information 444 in the first embodiment are not necessary.

Referring to FIG. 15, the configuration of radio terminal 200 according to the present embodiment will be described.

The wireless terminal 200 is a computer. The wireless terminal 200 includes a processor 201 and other hardware such as a memory 202, an input interface 203, and an output interface 204. The processor 201 is connected to other hardware via a signal line, and controls these other hardware.

The wireless terminal 200 includes an information management unit 211, a movement amount measurement unit 212, a movement amount determination unit 213, and a connection control unit 214 as functional elements. The functions of the information management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 are realized by software.

The processor 201 is a device that executes a wireless terminal program. The wireless terminal program is a program that realizes the functions of the information management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214. The processor 201 is, for example, a CPU.

The memory 202 is a device that stores a wireless terminal program. The memory 202 is, for example, a flash memory or a RAM.

The memory 202 stores movement amount information 221, movement determination information 222, and connection information 223.

The input interface 203 is at least one of a receiver that receives information from each base station 300 via the wireless network 101 and a port to which an input device operated by a user for inputting information is connected. The input device is, for example, a mouse, a keyboard, or a touch panel.

The output interface 204 is at least one of a transmitter that transmits information to each base station 300 via the wireless network 101 and a port to which a display that displays information on a screen is connected. The display is, for example, an LCD.

The wireless terminal program is read into the processor 201 and executed by the processor 201. The memory 202 stores not only the wireless terminal program but also the OS. The processor 201 executes the wireless terminal program while executing the OS.

The wireless terminal program and the OS may be stored in the auxiliary storage device. The auxiliary storage device is, for example, a flash memory or an HDD. The wireless terminal program and the OS stored in the auxiliary storage device are loaded into the memory 202 and executed by the processor 201.

Note that part or all of the wireless terminal program may be incorporated in the OS.

The wireless terminal 200 may include a plurality of processors that replace the processor 201. The plurality of processors share execution of the wireless terminal program. Each processor, like the processor 201, is a device that executes a wireless terminal program.

Data, information, signal values, and variable values used, processed, or output by the wireless terminal program are stored in the memory 202, the auxiliary storage device, or a register or cache memory in the processor 201.

The wireless terminal program includes information processing unit 211, movement amount measurement unit 212, movement amount determination unit 213, and connection control unit 214. This is a program that causes a computer to execute each procedure in which “unit” of each unit included in the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 is replaced with “procedure”. The wireless terminal program may be provided by being recorded on a computer-readable medium, or may be provided as a program product.

In the first embodiment, both the frequency control unit 412 and the connection control unit 424 are provided in the service area construction device 400, but as described above, in the present embodiment, only the frequency control unit 412 constructs the service area. The wireless terminal 200 is provided with the connection control unit 214 provided in the device 400.

*** Explanation of operation ***
With reference to FIG. 16, the operation of radio terminal 200 according to the present embodiment will be described. This operation corresponds to the connection method according to the present embodiment.

Also in this embodiment, the processing from step S11 to step S14 shown in FIG. 7 is performed. That is, as in the first embodiment, service area construction apparatus 400 constructs a double service area of a non-virtual cell area and a virtual cell area, and then sets each wireless terminal 200 according to the type of each wireless terminal 200. Are accommodated in either the non-virtual cell area or the virtual cell area.

When each wireless terminal 200 is accommodated in the service area, the information management unit 211 of each wireless terminal 200 generates information indicating the SSID of the cell connected to each wireless terminal 200 as connection information 223, and the generated connection Information 223 is stored in the memory 202.

In the present embodiment, processing from step S41 to step S47 is performed instead of processing from step S15 to step S19 shown in FIG. In the first embodiment, the movement amount measuring unit 422 of the service area construction device 400 monitors the change in the position of each wireless terminal 200 and measures the movement amount of each wireless terminal 200. In the present embodiment, The movement amount measurement unit 212 of each wireless terminal 200 monitors the change in the position of each wireless terminal 200 and measures the movement amount of each wireless terminal 200.

In step S41, the movement amount measuring unit 212 acquires the position information of the wireless terminal 200. The process of step S41 is performed for each preset measurement time. Specifically, the movement amount measurement unit 212 acquires a positioning result obtained by a GPS receiver or sensor built in the wireless terminal 200 as position information. “GPS” is an abbreviation for Global Positioning System.

In step S42, if the preset measurement period has not ended, the process of step S41 is performed again. If the measurement period ends, the process of step S43 is performed.

In step S43, the movement amount measuring unit 212 calculates the amount of change in the position of the wireless terminal 200 within the measurement period as the movement amount from the position information acquired in step S41 within the measurement period. Alternatively, the movement amount measurement unit 212 calculates the amount of change in the position of the wireless terminal 200 within the measurement period from the position information acquired in step S41 within the measurement period, and uses the calculated amount of change using an arbitrary expression. Convert to travel.

The movement amount measuring unit 212 generates information indicating the movement amount calculated in step S43 as the movement amount information 221 and stores the movement amount information 221 in the memory 202. The movement amount information 221 is referred to by the movement amount determination unit 213 in step S44.

In step S44, the movement amount determination unit 213 compares the movement amount calculated in step S43 with a threshold value, and determines the magnitude of the movement amount of the wireless terminal 200. If the movement amount is less than the threshold value, the process of step S45 is performed. If the movement amount is greater than or equal to the threshold value, the process of step S46 is performed.

The movement amount determination unit 213 generates information indicating the determination result in step S44 as movement determination information 222, and stores the movement determination information 222 in the memory 202. The movement determination information 222 is referred to by the connection control unit 214 in order to determine which process of step S45 and step S46 is to be performed.

In step S45 and step S46, the connection control unit 214 determines whether the wireless terminal 200 is connected between the cells in the non-virtual cell area and the cells in the virtual cell area that overlap each other according to the movement amount of the wireless terminal 200. Switch the connected cell. Specifically, when the wireless terminal 200 is connected to a cell in the virtual cell area and the movement amount of the wireless terminal 200 is smaller than the threshold, in step S45, the connection control unit 214 The connection destination cell of 200 is switched to a cell in the non-virtual cell area that overlaps with the cell to which the wireless terminal 200 is connected. On the other hand, if the movement amount of the wireless terminal 200 is not smaller than the threshold value, the connection control unit 214 does not switch the connection destination cell of the wireless terminal 200 in step S46. That is, the connection control unit 214 maintains the connection of the wireless terminal 200 to the cell in the virtual cell area. When the wireless terminal 200 is connected to a cell in the non-virtual cell area and the movement amount of the wireless terminal 200 is greater than the threshold, the connection control unit 214 determines that the wireless terminal 200 The connection destination cell is switched to a cell in the virtual cell area that overlaps with the cell to which the wireless terminal 200 is connected. In the present embodiment, even when the movement amount of the wireless terminal 200 becomes the same as the threshold, in step S46, the connection control unit 214 connects the connection destination cell of the wireless terminal 200 to the wireless terminal 200. Switch to a cell in the virtual cell area that overlaps the cell. On the other hand, if the movement amount of the wireless terminal 200 is smaller than the threshold value, the connection control unit 214 does not switch the connection destination cell of the wireless terminal 200 in step S45. That is, the connection control unit 214 maintains the connection of the wireless terminal 200 to the cell in the non-virtual cell area.

Thus, in the present embodiment, after the service area construction device 400 accommodates each wireless terminal 200 in either the non-virtual cell area or the virtual cell area, each wireless terminal 200 The amount of movement is periodically measured, and the accommodation destination of each wireless terminal 200 is voluntarily changed according to the determination result of the amount of movement.

In step S47, the information management unit 211 updates the connection information 223 stored in the memory 202 as necessary. Specifically, when the connection destination cell of the wireless terminal 200 is switched in step S45 or step S46, the information management unit 211 uses the connection information 223 of the wireless terminal 200 as the SSID of the cell to which the wireless terminal 200 is connected. Update the information to indicate. The information management unit 211 transmits the updated connection information 223 to the service area construction device 400 via the base station 300. When receiving the connection information 223, the information management unit 421 of the service area construction device 400 updates the connection information 442 of the corresponding wireless terminal 200 stored in the memory 402. Specifically, the information management unit 421 updates the connection information 442 of the wireless terminal 200 received from the wireless terminal 200 when the connection destination cell of any of the wireless terminals 200 is switched. Update at 223.

After step S47, step S41 is performed again.

*** Explanation of the effect of the embodiment ***
In the present embodiment, instead of service area construction device 400, wireless terminal 200 switches between a virtual cell area and a non-virtual cell area according to the amount of movement of wireless terminal 200. Therefore, the throughput can be improved for the wireless terminal 200 with a small movement amount while suppressing the processing load on the network side. For the radio terminal 200 with a large amount of movement, it is possible to reduce the frequency of handovers to make it difficult for communication interruptions to occur and to stabilize communication.

*** Other configurations ***
In the present embodiment, the functions of the base station monitoring control unit 410 and the terminal monitoring control unit 420 are realized by software, as in the first embodiment. However, as in the modification of the first embodiment, The functions of the station monitoring control unit 410 and the terminal monitoring control unit 420 may be realized by a combination of software and hardware.

In the present embodiment, the functions of the information management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 are realized by software, but as a modification, the information management unit 211, the movement amount measurement unit The functions of 212, the movement amount determination unit 213, and the connection control unit 214 may be realized by a combination of software and hardware. That is, some of the functions of the information management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 may be realized by dedicated hardware, and the rest may be realized by software.

The dedicated hardware is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, a logic IC, a GA, an FPGA, or an ASIC.

Both the processor 201 and the dedicated hardware are processing circuits. That is, regardless of whether the functions of the information management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 are realized by software or a combination of software and hardware, The functions of the management unit 211, the movement amount measurement unit 212, the movement amount determination unit 213, and the connection control unit 214 are realized by a processing circuit.

100 wireless communication system, 101 wireless network, 200 wireless terminal, 201 processor, 202 memory, 203 input interface, 204 output interface, 211 information management unit, 212 movement amount measurement unit, 213 movement amount determination unit, 214 connection control unit, 221 Movement amount information, 222 movement determination information, 223 connection information, 300 base station, 301 wireless unit, 302 wireless unit, 400 service area construction device, 401 processor, 402 memory, 403 input interface, 404 output interface, 410 base station monitoring control Unit, 411 arrangement management unit, 412 frequency control unit, 420 terminal monitoring control unit, 421 information management unit, 422 movement amount measurement unit, 423 movement amount determination unit, 424 connection control unit, 425 transfer History creation section, 431 arrangement information 432 frequency information 441 type information 442 connection information 443 movement amount information, 444 movement determination information 501 flow line, 502 flow line.

Claims (14)

When a wireless terminal connected to a cell and performing wireless communication via a base station moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal becomes the movement destination cell of the wireless terminal In a switching wireless communication system,
The non-virtual cell area, which is a service area where the frequency used for the wireless communication in the cells adjacent to each other is different, and the frequency used for the wireless communication in the cell adjacent to each other are common and overlap with the non-virtual cell area. In order to construct a virtual cell area which is a service area, a frequency used in each cell in the non-virtual cell area and a frequency used in each cell in the virtual cell area are set in the base station A frequency control unit,
A wireless communication system comprising: a connection control unit that connects the wireless terminal to a cell selected from a cell in the non-virtual cell area and a cell in the virtual cell area that overlap each other. The connection control unit selects a connection destination cell of the wireless terminal from among the cells in the non-virtual cell area and the cell in the virtual cell area, which overlap each other according to the type of the wireless terminal. The wireless communication system according to claim 1. The connection control unit determines a connection destination cell of the wireless terminal between a cell in the non-virtual cell area and a cell in the virtual cell area, which overlap each other according to a movement amount of the wireless terminal. The wireless communication system according to claim 1 or 2, wherein switching is performed. The connection control unit, when the movement amount of the wireless terminal is larger than a threshold when the wireless terminal is connected to a cell in the non-virtual cell area, the connection destination cell of the wireless terminal, The wireless communication system according to claim 3, wherein the wireless communication system switches to a cell in the virtual cell area that overlaps with a cell to which the wireless terminal is connected. The connection control unit, when the movement amount of the wireless terminal is smaller than a threshold when the wireless terminal is connected to a cell in the virtual cell area, the connection destination cell of the wireless terminal, The radio | wireless communications system of Claim 3 or 4 which switches to the cell in the said non-virtual cell area which overlaps with the cell to which the radio | wireless terminal is connected. The wireless communication system according to any one of claims 3 to 5, further comprising a movement amount measurement unit that monitors switching of a connection destination of the wireless terminal and measures a movement amount of the wireless terminal. The wireless communication system according to any one of claims 3 to 5, further comprising a movement amount measurement unit that monitors a change in position of the wireless terminal and measures a movement amount of the wireless terminal. When the wireless terminal moves between adjacent service areas, the connection destination cell of the wireless terminal changes from a cell in the service area of the wireless terminal to a cell in the service area of the wireless terminal. Switched
The frequency control unit is configured to configure each cell in each virtual cell area as the virtual cell area in order to construct at least two virtual cell areas having different frequencies used for the wireless communication in virtual cell areas adjacent to each other. The radio | wireless communications system of any one of Claim 1 to 7 which sets the frequency used by the said base station. The frequency control unit changes a combination of cells included in each virtual cell area according to a movement history of the wireless terminal, and sets a frequency used in each cell in each virtual cell area after the change to the base station The radio | wireless communications system of Claim 8 set to. The wireless terminal, the base station, and a service area construction device that is a device independent of the wireless terminal and the base station,
The radio communication system according to claim 1, wherein the frequency control unit and the connection control unit are provided in the service area construction device. The wireless terminal, the base station, and a service area construction device that is a device independent of the wireless terminal and the base station,
The frequency control unit is provided in the service area construction device,
The wireless communication system according to claim 1, wherein the connection control unit is provided in the wireless terminal. When a wireless terminal connected to a cell and performing wireless communication via a base station moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal becomes the movement destination cell of the wireless terminal In the connection method to switch,
A service area constructing apparatus that is an apparatus independent of the base station and the wireless terminal, and a cell that is adjacent to a non-virtual cell area that is a service area in which frequencies used for the wireless communication are different in adjacent cells. In order to construct a virtual cell area that is a service area that shares the same frequency used for the wireless communication and overlaps the non-virtual cell area, a frequency used in each cell in the non-virtual cell area; Set the frequency used in each cell in the virtual cell area to the base station,
A connection method in which the wireless terminal connects to a cell selected from a cell in the non-virtual cell area and a cell in the virtual cell area, which overlap each other. When a wireless terminal connected to a cell and performing wireless communication via a base station moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal becomes the movement destination cell of the wireless terminal In a service area construction device for constructing two or more service areas for a wireless network to be switched,
The non-virtual cell area, which is a service area where the frequency used for the wireless communication in the cells adjacent to each other is different, and the frequency used for the wireless communication in the cell adjacent to each other are common and overlap with the non-virtual cell area. In order to construct a virtual cell area which is a service area, a frequency used in each cell in the non-virtual cell area and a frequency used in each cell in the virtual cell area are set in the base station A frequency control unit,
A service area construction apparatus comprising: a connection control unit that connects the wireless terminal to a cell selected from a cell in the non-virtual cell area and a cell in the virtual cell area that overlap each other. When a wireless terminal connected to a cell and performing wireless communication via a base station moves to an adjacent cell in the same service area, the connection destination cell of the wireless terminal becomes the movement destination cell of the wireless terminal For a computer that constructs two or more service areas for the wireless network to be switched,
The non-virtual cell area, which is a service area where the frequency used for the wireless communication in the cells adjacent to each other is different, and the frequency used for the wireless communication in the cell adjacent to each other are common and overlap with the non-virtual cell area. In order to construct a virtual cell area which is a service area, a frequency used in each cell in the non-virtual cell area and a frequency used in each cell in the virtual cell area are set in the base station Frequency control processing to
A service area construction program for executing connection control processing for connecting the wireless terminal to a cell selected from a cell in the non-virtual cell area and a cell in the virtual cell area, which overlap each other.

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