JP2006352477A - Radio communication system, radio base station, monitoring device and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently operate each radio base station while preventing degradation of communication quality when the number of radio terminals which perform communication is reduced in a radio communication system having a predetermined management site covered by areas in charge adjacently arranged to a plurality of radio base stations. <P>SOLUTION: A radio base station AP1 has means 14, 17 for acquiring information about the number of connected radio terminals in the present station and each radio base station, respectively, and a means 18 for adjusting ranges of each area in charge by reducing or extinguishing an area in charge by one of the plurality of radio base stations AP1-AP4 according to the acquired information about the number of connected radio terminals and on the other hand, expanding an area in charge by one of other radio base stations so as to compensate the area in charge to be reduced or extinguished, changing an area in charge by the present stations based on adjustment results and making each of other radio base stations change areas in charge and appropriately adjusts ranges of areas in charge of each radio base station. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a radio communication system, a radio base station, a monitoring apparatus, and a control method thereof.

 2. Description of the Related Art In recent years, wireless communication systems for wireless communication by wireless terminals such as PCs, portable information terminals, mobile phones, and the like having wireless communication functions have been rapidly spread. Various data can be transmitted and received via a wireless base station (access point) having a wireless cover area.

  In this type of radio communication system, there is usually a certain limit on the number of radio terminals that can access the same radio base station in order to maintain the communication quality. In order to enable more wireless terminals to communicate with each other at the same time, a plurality of wireless base stations are arranged in the same management site.

  In the case where a plurality of wireless base stations are arranged in the same management site as described above, it is possible to cope with a time zone (for example, daytime) in which the number of wireless terminals performing communication is relatively large from the viewpoint of user convenience. When a number of wireless base stations are arranged, it is not possible to efficiently use all of the arranged wireless base stations in a time zone where the number of wireless terminals performing communication is relatively small (for example, at night) (that is, There may be a problem that the radio base stations are in an excessive state) and the power consumed by them is wasted.

  In order to solve such a problem, for example, in a radio base station, when a power ON time preset by a timer is detected for a power supply control unit that controls power supply to the radio unit, a power supply start signal On the other hand, by sending a power supply stop signal when the power OFF time is detected, it is possible to reduce the power consumption in the time zone when there is no call or communication without requiring human operation, and the running cost Is known (see Patent Document 1).

Further, in a wireless communication system including a plurality of access points that connect wired communication and wireless communication to manage a plurality of wireless terminals and a plurality of wireless terminals, the base station is connected to the number of wireless terminals. If the number of access points with the fewest number of connected devices is specified when the number is less than or equal to the predetermined number, and the wireless terminal connected to the specified access points is not in data communication, the access point Is known to stop power supply or switch to a low power consumption mode (see Patent Document 2).
JP 2004-356838 A Japanese Patent Laid-Open No. 2004-165953

  However, the technology as described in Patent Document 1 has a specific day or a specific time zone in which a wireless terminal is not used in a predetermined management site (for example, a subway yard or a commercial building that is a management site is regularly installed). Therefore, it is difficult to apply to a radio base station located at a management site where a specific date and a specific time zone are not fixed.

  Further, in the technology as described in Patent Document 2, when the number of wireless terminals connected to an access point decreases, power supply to an access point with a small number of connected devices is stopped or switched to a low power consumption mode. The connection of the wireless terminal that should originally be connected to the access point can be supplemented by another access point accommodated in the same housing. However, in the above technique, in order to supplement the access point that stops power supply or switches to the low power consumption mode with another access point, if the wireless cover areas of a plurality of access points are arranged to overlap, the frequency band used for wireless communication There is a problem that radio wave interference is likely to occur due to (channel) restrictions, and the number of wireless terminals that can be connected to each access point is limited.

  In addition, as a method of suppressing radio wave interference between such access points, the wireless coverage areas of multiple access points are generally not duplicated within a given management site (allowing stable movement of wireless terminals between base stations) (Including the case where a part of the wireless cover area is overlapped as much as possible). However, in the above technique, after power supply to a predetermined access point is stopped or switched to the low power consumption mode, there may be a problem that wireless terminals cannot communicate in the area that was the wireless cover area of the access point. .

  The present invention has been made based on such knowledge, and in a wireless communication system having a predetermined management site that is covered by an assigned area adjacent to a plurality of wireless base stations, communication is performed within the management site. When the number of wireless terminals that perform communication decreases, the wireless base station can be operated efficiently while adjusting the range of the area in which each wireless base station is in charge while preventing deterioration in communication quality A main object is to provide a communication system radio base station, a monitoring apparatus, and a control method thereof.

  In order to solve the above-described problems, a radio communication system according to the present invention is a radio communication system having a predetermined management area covered by a charge area arranged adjacent to each other of a plurality of radio base stations. At least one of the plurality of radio base stations includes first connection management means for acquiring information on the number of connected radio terminals in the own station, and connection of radio terminals in each radio base station other than the own station. The second connection management means for acquiring the information on the number of units, and one of the wireless base stations in the plurality of wireless base stations according to the information on the number of connected wireless terminals respectively acquired by the first and second connection management means While reducing the area in charge of a station or expanding the area in charge of any other radio base station to supplement the area to be reduced or eliminated, each assigned area Based on the adjustment results of the assigned area adjustment means and the assigned area adjustment means, the assigned area of the own station is changed, and the assigned assigned area is changed so that each radio base station other than the assigned station changes the assigned area. And a means.

  According to this, in a radio communication system having a predetermined management area covered by a responsible area arranged adjacent to a plurality of radio base stations, the number of radio terminals performing communication in the management area decreases, and radio base stations In the case of an excessive state, the area in charge of any radio base station is reduced or eliminated, while the area in charge of any other radio base station is expanded to compensate for the area to be reduced or eliminated. Therefore, it is possible to cover a wide range of management areas with fewer radio base stations, and to reduce the frequency of radio interference between multiple radio base stations and the movement of radio terminals between base stations (roaming and handover). it can. As a result, it is possible to operate each radio base station efficiently while preventing a decrease in communication quality, and it is possible to reduce the processing load accompanying movement between base stations in each radio terminal.

  In the wireless communication system, as described in claim 2, the assigned area changing unit adjusts transmission power to change the assigned area of the own station, and sets assigned areas in each of the radio base stations other than the own station. Each transmission power can be adjusted to be changed. According to this, it becomes possible to easily change the area in charge of the radio base station. Further, by suppressing the transmission power so that the area in charge of the radio base station is reduced or eliminated, the power consumption in the radio base station can be reduced.

  In the wireless communication system, as described in claim 3, the assigned area adjustment unit determines a radio base station that reduces, disappears, or expands the assigned area based on a priority set in advance for a plurality of radio base stations. It can be set as the structure to do. According to this, by setting priority based on conditions such as a place where each radio base station is arranged, it is possible to appropriately adjust the assigned area in each radio base station.

  In the wireless communication system, as described in claim 4, the assigned area adjustment unit is in charge of each wireless base station when the number of wireless terminals connected to any of the wireless base stations is equal to or less than a prescribed number. It can be set as the structure which starts adjustment of the range of an area | region. According to this, it is possible to adjust the range of the assigned area at an appropriate timing in order to reduce or eliminate the assigned area of the radio base station in which the number of connected wireless terminals is equal to or less than the specified number.

  In the wireless communication system, as described in claim 5, the plurality of wireless base stations include a predetermined wireless base station capable of expanding the assigned area over the entire management area, and the assigned area adjusting means includes a predetermined area. And a configuration in which the range of each assigned area is adjusted so that the assigned area of the predetermined radio base station is expanded on the assigned assigned area while the assigned assigned areas of all the radio base stations are extinguished. can do. According to this, since the entire management area is covered by the area in charge of one radio base station, it is possible to prevent radio wave interference between a plurality of radio base stations and movement of radio terminals between base stations.

  In the radio communication system, as shown in claim 6, the assigned area changing means instructs each radio base station other than the own station to change the assigned area, and the other radio base stations other than the own station Upon receiving an instruction to change the assigned area, a determination unit that determines whether the assigned area can be changed and a determination result of the determination unit are notified to the radio base station that has received the instruction to change the assigned area. It can be set as the structure provided with the notification means. According to this, the radio base station that has received the instruction to change the assigned area can determine whether to accept the change instruction based on the connection status of the wireless terminal, etc. Inconvenience due to being done can be avoided.

  According to another aspect of the present invention, there is provided a radio communication system having a predetermined management area covered by areas in charge of a plurality of radio base stations arranged adjacent to each other. Information acquisition means for acquiring information on the number of connected wireless terminals in the base station, and responsible for any of the wireless base stations in the plurality of wireless base stations according to the information on the number of connected wireless terminals acquired by the information acquiring means Communication adjustment that adjusts the range of each of the assigned assigned areas by expanding or reducing the assigned area of any other radio base station so that the assigned assigned area is reduced or eliminated while the area is reduced or eliminated And a communication changing means for causing a plurality of radio base stations to change the assigned area based on the adjustment result of the communication adjusting means.

  According to this, in a radio communication system having a predetermined management area covered by a responsible area arranged adjacent to a plurality of radio base stations, the number of radio terminals performing communication in the management area decreases, and radio base stations In the case of an excessive state, the area in charge of any radio base station is reduced or eliminated, while the area in charge of any other radio base station is expanded to compensate for the area to be reduced or eliminated. As a result, it is possible to cover a wide management area with fewer radio base stations, and to reduce radio wave interference between a plurality of radio base stations and the frequency of movement of radio terminals between base stations. As a result, it is possible to operate each radio base station efficiently while preventing a decrease in communication quality, and it is possible to reduce the processing load accompanying movement between base stations in each radio terminal.

  In the wireless communication system, as described in claim 8, when the communication adjustment unit receives an adjustment request from any of the wireless base stations, the communication adjustment unit adjusts the range of each assigned area adjacently arranged, and the communication change unit includes Based on the adjustment result of the communication adjustment means, a plurality of radio base stations are configured to change the assigned area. According to this, when the number of connected wireless terminals is reduced, it becomes possible to adjust the range of the assigned area at an appropriate timing.

  The radio base station according to the present invention is a radio base station that is adjacent to another radio base station and covers a radio area assigned to the radio station, as defined in claim 9, First connection management means for obtaining information on the number of connected terminals, second connection management means for obtaining information on the number of connected wireless terminals in each of the wireless base stations other than the own station, According to the information on the number of connected wireless terminals acquired by the second connection management means, the assigned area of the own station or any other wireless base station is reduced or eliminated while the assigned area to be reduced or eliminated is determined. The assigned area adjustment means for adjusting the range of each assigned area of the adjacent radio base station by expanding the assigned area of the own station or any other radio base station so as to compensate, and the assigned area adjustment means Adjustment result Based on the above, if it is necessary to change its own area, change its own area by controlling its own power, and if it is necessary to change another radio base station other than its own station It is configured to include a responsible area changing means for causing the base station to change the responsible area.

  The monitoring device of the present invention is a monitoring device connected to a plurality of radio base stations via a network, as described in claim 10, and information for acquiring information on the number of connected radio terminals in the plurality of radio base stations, respectively. In accordance with the information on the number of connected wireless terminals acquired by the acquisition means and the information acquisition means, the assigned area of any of the radio base stations in the plurality of radio base stations is reduced or eliminated while the assigned area to be reduced or eliminated Based on the adjustment result of the communication adjustment means that adjusts the range of each charge area of the adjacent radio base station by expanding the charge area of any other radio base station so as to compensate And a communication change means for changing the assigned area to a plurality of radio base stations.

  According to another aspect of the present invention, a radio base station is connected to a monitoring apparatus via a network, and is adjacent to another radio base station and covers a radio area assigned to the own radio station. The information notifying means for notifying the monitoring device of the number of connected wireless terminals connected to the own station, and controlling the power of the own station when the monitoring device is instructed to change the radio area Thus, the area in charge is changed.

  The radio communication system control method according to the present invention is a radio communication system control method having a predetermined management area covered by areas assigned adjacent to each other of a plurality of radio base stations. In at least one of the plurality of radio base stations, a first connection management step of acquiring information on the number of connected radio terminals in the own station, and connection of radio terminals in each other radio base station other than the own station One of the radio base stations in the plurality of radio base stations according to the second connection management step for acquiring the information on the number of units and the information on the number of connected wireless terminals acquired in the first and second connection management steps, respectively. By reducing or eliminating the area in charge of the station, while expanding the area in charge of any other radio base station to compensate for the area to be reduced or eliminated Based on the adjustment result of the assigned area adjustment step and the assigned area adjustment step, the transmission power is adjusted to change the assigned area of the own station and other than the assigned station. And a responsible area changing step of adjusting each transmission power to change the assigned area in each of the radio base stations.

  According to another aspect of the present invention, there is provided a control method for a radio communication system having a predetermined management area covered by areas in charge of a plurality of radio base stations arranged adjacent to each other. The information acquisition step for acquiring information on the number of connected wireless terminals in the plurality of wireless base stations, and the information on the number of connected wireless terminals in the information acquiring step, depending on the information on the number of connected wireless terminals. While reducing the area in charge of each radio base station, while expanding the area in charge of any other radio base station to compensate for the area to be reduced or eliminated, Based on the communication adjustment step for adjusting the range and the adjustment result in the communication adjustment step, the assigned area in the plurality of radio base stations should be changed. Configured to have a communication change step of adjusting the transmit power of s.

  According to the present invention, in a wireless communication system having a predetermined management site covered by a responsible area arranged adjacent to a plurality of wireless base stations, when the number of wireless terminals performing communication within the management site decreases. By adjusting the range of the assigned area of each radio base station, it is possible to operate each radio base station efficiently while preventing a decrease in communication quality.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing a schematic configuration of a wireless communication system according to the first embodiment of the present invention. The wireless communication system 1 has a configuration in which four wireless base stations (AP) AP1 to AP4 are connected to each other by a wired LAN (Local Area Network) 2.

  AP1-AP4 has a predetermined wireless cover area (area in charge) 3-6, and relays wireless communication by controlling connections from a plurality of wireless terminals (STA) STA1-STA10. Thereby, STA1-STA10 can connect to each AP and use various communication services. AP1-AP4 can perform wireless communication according to a frequency band and a transmission speed defined by a wireless LAN standard such as IEEE802.11b, for example. In AP1-AP4, one wireless channel includes a plurality of wireless channels. Shared by STAs, wireless communication by a plurality of STAs is possible via each of AP1-AP4.

  The wireless cover area 3-6 is arranged so that wireless communication is possible over the entire management site (management area) 7 of the wireless communication system 1. FIG. 1 shows a case where the range of each wireless cover area 3-6 is in a reference state (that is, a state before adjusting the range of the wireless cover area 3-6). 6 are arranged adjacent to each other within a substantially equal range so as to suppress radio wave interference between AP1 and AP4. As will be described later, AP1 to AP4 can change the range of each wireless cover area 3-6 by adjusting the transmission power.

  The STA1-STA10 includes a PC having a predetermined wireless communication function connectable to the AP1-AP4, a portable information terminal, a mobile phone, and the like. For example, the STA1-STA10 can confirm the presence of the AP1-AP4 by a beacon signal including connection information periodically transmitted from the AP1-AP4, and can connect to each AP1-AP4 through a predetermined authentication step. . Here, STA1-STA3 are in the wireless cover area 3 and can be connected to AP1, STA4-STA6 is in the wireless cover area 4 and can be connected to AP2, and STA7 and STA8 are wireless covers. The STA 9 and the STA 10 are in the area 5 and can be connected to the AP 3, and the STA 9 and the STA 10 are in the wireless cover area 6 and can be connected to the AP 4. Each of the STA1 to STA10 can freely move within the management site 7, can change the connected base station as appropriate, and can communicate with each other. When moving from a predetermined wireless cover area to another wireless cover area, In this case, processes such as establishment, disconnection, and presence confirmation of communication are executed according to a known communication protocol.

  FIG. 2 is a functional block diagram showing a schematic configuration of the radio base station shown in FIG. Here, the configuration of AP1 of the radio base station is shown, but the same configuration is possible for the other AP2-AP4. AP 1 includes a wireless unit 11, a wireless control unit 12, a terminal connection management unit 13, a terminal number management unit 14, an information notification unit 15, an adjacent AP information management unit 16, and an adjacent AP terminal number management unit 17. The wireless area adjustment unit 18 and the wired network control unit 19 are mainly configured. The operations of the above-described units described below can be realized by, for example, a CPU (not shown) included in the AP 1 executing a process based on a predetermined control program.

  The wireless unit 11 includes an antenna that transmits and receives wireless radio waves for wireless communication with the wireless terminal STA. The wireless control unit 12 comprehensively controls communication processing via the wireless unit 11. The radio control unit 12 performs a process such as demodulation on the radio signal received from the STA by the radio unit 11 and outputs the signal to the terminal connection management unit 13, while modulating the signal to be transmitted to the STA. Is output to the wireless unit 11. In addition, the wireless control unit 12 performs predetermined authentication processing for access from the STA, and when a regular connection is established, information indicating that the STA has been connected is sent to the terminal connection management unit 13. Sent as a connection notification. Further, the radio control unit 12 can adjust the transmission power in the radio unit 11 in accordance with a control command from the radio area adjustment unit 18. The range of the wireless cover area is changed by adjusting the transmission power. For example, the wireless cover area is enlarged or reduced from the reference state shown in FIG. 1, or the wireless cover area is extinguished by turning off the transmission power. be able to.

  The terminal connection management unit 13 receives the connection notification from the radio control unit 12 and manages information on the STA connected to the own station. The terminal connection management unit 13 stores the content of the STA connection notification in a memory (not shown) as connection information table data. As shown in FIG. 3, this connection information table includes, for example, STA identifiers for identifying connected STAs, information on those connections (connection date and connection time), and the like.

  The terminal number management unit (first connection management means) 14 statistically processes the data in the connection information table by the terminal connection management unit 13 to obtain information on the number of connected STAs (hereinafter, “number of terminals”). Information ”) and manage them in time series. The terminal number management unit 14 stores the terminal number information in a memory (not shown) as data of the connected number statistics table. As shown in FIG. 4, the connection number statistics table includes, for example, date, time, number of connections, and the like. Here, the case where the terminal number information is processed every hour is illustrated, but the processing timing can be variously changed according to the connection status of the STA, for example, the connection of a new STA It is also possible to process the number of terminals information every time.

  The information notification unit 15 provides information on the number of terminals of the own station used for adjusting the range of the radio coverage area, which will be described later, to APs other than the own station in the radio communication system 1 (hereinafter referred to as “adjacent AP”) Information on the location and operation (hereinafter referred to as “AP information”) is notified via the LAN. The AP information includes, for example, information related to the location such as an IP address and a MAC address indicating the location, and information related to the operation of the own station such as a transmission power value.

  The adjacent AP information management unit 16 manages AP information acquired from each adjacent AP via the LAN 2. The AP information is used for adjusting the range of the wireless cover area described later. The adjacent AP information management unit 16 stores the acquired AP information in a memory (not shown) as data of the adjacent AP information table. In this adjacent AP information table, as shown in FIG. 5, for example, an adjacent AP identifier for identifying the adjacent AP, an IP address indicating the location of the adjacent AP, and a transmission power value indicating the setting of the wireless unit of the adjacent AP (The power level at which the AP transmits to the STA is shown in dBm), a radio channel, and the like.

  The adjacent AP terminal number management unit (second connection management means) 17 manages the terminal number information respectively acquired from the adjacent AP via the LAN 2. The adjacent AP terminal number management unit 17 stores the terminal number information in a memory (not shown) as data of the adjacent AP terminal number statistical table. As shown in FIG. 6, the statistical table includes, for example, an adjacent AP identifier for identifying an adjacent AP, a date, a time, and the number of connected devices. Here, a case where the number-of-terminals information is processed every hour is shown as an example, but the processing timing can be variously changed as in the case of FIG.

  The wireless area adjustment unit (responsible area adjusting means, responsible area changing means) 18 adjusts the range of the wireless cover area of the own station and the adjacent AP. In addition, the wireless area adjustment unit 18 changes the wireless cover area by sending a transmission power control notification to the wireless control unit 12 of the local station based on the adjustment result, and changes to the adjacent AP other than the local station. In order to change the wireless cover area, an area adjustment notification instructing the adjacent AP to change the wireless cover area is transmitted. This area adjustment notification includes a transmission power control command for the radio control unit of the adjacent AP.

  On the other hand, when receiving the area adjustment notification from the adjacent AP, the wireless area adjustment unit 18 functions as a notification unit that notifies the AP that the area adjustment notification has been accepted. As another method, upon receiving an area adjustment notification from the adjacent AP, the wireless area adjustment unit 18 determines whether or not the wireless cover area of the local station can be adjusted (that is, whether or not to accept an instruction to change the wireless cover area). ) And a notification means for notifying the determination result to the radio base station that has received the area adjustment notification. In this case, when the determination unit determines that the wireless cover area cannot be adjusted, the wireless cover area is not changed. Note that, when an area adjustment notification is received from an adjacent AP, the method of changing the wireless cover area in the own station is the same as that in the case of sending the above area adjustment notification.

  Here, the range of the radio coverage area is adjusted when the number of STAs connected to the whole AP1-AP4 or at least a part thereof decreases and the number of STAs is small (that is, the AP is in an excessive state). If it is determined, one of the wireless coverage areas of AP1 to AP4 is reduced or eliminated, while any other wireless coverage area is enlarged so as to supplement the reduced or eliminated wireless coverage area. It can be carried out. Here, for example, when the number of connected STAs is equal to or less than a predetermined number set in advance, or when it is predicted that the number of connected STAs is equal to or less than the predetermined number due to a change in the number of STAs over time, “the number of STAs is small” Can be determined. Further, the degree of reduction, disappearance, or enlargement in the wireless cover area can be determined in consideration of various conditions such as the number of STAs connected to each AP and the installation position of the AP.

  Note that priorities can be set in advance for AP1 to AP4, and based on the priorities, APs that reduce, disappear, or expand the wireless cover area can also be determined. Further, the adjustment of the range of the wireless cover area can be started at a timing when the number of connected STAs in any one of AP1 to AP4 is equal to or less than a predetermined number set in advance.

  The wired network control unit 19 controls communication with an adjacent AP via the LAN 2. That is, the communication operation performed by the information notification unit 15, the adjacent AP information management unit 16, the adjacent AP terminal number management unit 17, and the wireless area adjustment unit 18 with respect to the adjacent AP is all controlled by the wired network control unit 19. The

  FIG. 7 is a flowchart showing an AP information management operation in the radio base station shown in FIG. First, when AP1 is activated (ST101), the information notification unit 15 notifies the AP information of its own station to neighboring APs connected to the LAN 2 in the wireless communication system 1 (ST102). The AP information notified when the AP 1 is activated includes a request for AP information for the neighboring AP. Therefore, AP1 is in a state where AP information from the neighboring AP can be received at all times, and when the neighboring AP information management unit 16 receives a notification of AP information from the neighboring AP (ST103: YES), the AP information is shown in FIG. The data is stored and managed in a predetermined memory as data of the adjacent AP information table (ST104). The operations in ST103 and ST104 are repeatedly executed, and the data in the adjacent AP information table is updated as appropriate.

  In ST103, when the AP information request is included when the AP information is received from the neighboring AP, the information notification unit 15 transmits the AP information request in parallel with the operation of ST104. It is possible to notify the AP information of the own station to the AP.

  FIG. 8 is a flowchart showing the management operation of the number of connected wireless terminals in the wireless base station shown in FIG. First, when a new STA accesses AP1 and a connection is permitted, the radio control unit 12 notifies the terminal connection management unit 13 of a connection (ST201: YES), where the terminal connection management unit 13 adds and manages connection information of a new STA as data in the connection information terminal table of FIG. 3 based on the connection notification (ST202). Subsequently, the terminal number management unit 14 adds and manages the terminal number information from the terminal connection management unit 13 as data in the connection number statistics table of FIG. 4 (ST203). At this time, when there is a request for the number of terminals from the adjacent AP, the information notification unit 15 can appropriately notify the terminal number information of the own station to the requesting AP based on the connection number statistics table.

  Next, the information notification unit 15 periodically notifies the adjacent AP of the terminal number information of the own station (ST204). At this time, the information notification unit 15 can request the terminal number information from the adjacent AP that notifies the terminal number information. Thereafter, when the adjacent AP terminal number management unit 17 receives the terminal number information from the adjacent AP (ST205: YES), the terminal number information is added and managed as data of the adjacent AP terminal number statistical table of FIG. 6 (ST206). ). The operations of ST205 and ST206 are repeatedly executed, and the data in the adjacent AP terminal number statistical table is updated as appropriate.

  In ST206, when the terminal number information request is included when receiving the terminal number information from the adjacent AP, the information notification unit 15 requests the terminal number information in parallel with the operation of ST206. It is possible to notify the terminal number information of the own station to the AP that has transmitted.

  FIG. 9 is a flowchart showing a first adjustment operation of the radio coverage area in the radio base station shown in FIG. Here, it is the operation when the local station sends an area adjustment notification to the adjacent AP, and the adjacent AP that has received the area adjustment notification does not determine whether or not the radio cover area can be adjusted. An example of the case is shown.

  First, when the terminal number management unit 14 determines that the number of STAs connected to its own station is small according to the connection number statistics table of FIG. 4 (ST301: YES), the wireless area adjustment unit 18 adjusts the wireless cover area. Is requested (ST302). Subsequently, the wireless area adjustment unit 18 requests terminal number information from the adjacent AP terminal number management unit 17 to acquire the latest terminal number information of the adjacent AP and add it to the adjacent AP terminal number statistics table of FIG. ST303), it is determined whether to adjust the range of the radio coverage area at each AP in the management site 7 (ST304).

  Next, the wireless area adjustment unit 18 acquires AP information of the adjacent AP of FIG. 5 from the adjacent AP information management unit 16 in order to specify the notification destination of the area adjustment notification (ST305). Therefore, the wireless area adjustment unit 18 sends an area adjustment notification to the adjacent AP according to the previous adjustment result, and the adjacent AP that has received the area adjustment notification notifies the AP that the area adjustment notification has been accepted. Notification is made (ST306). Thereafter, in the own station, the radio control unit 12 adjusts the transmission power according to the adjustment result of the radio area adjustment unit 18 to change the radio cover area. Similarly, the adjacent AP also sets the transmission power according to the adjustment result. The wireless coverage area is changed by adjustment (ST307).

  For example, if the number of wireless terminals connected to the own station is less than a predetermined number and the number of connected to adjacent APs is also less than the predetermined number, the power supply to the wireless unit of the own station is stopped and the wireless base station is suspended. On the other hand, the neighboring AP increases the transmission power so as to cover its own wireless area.

  FIG. 10 is a flowchart showing a second adjustment operation of the radio coverage area in the radio base station shown in FIG. Here, an operation is shown when an area adjustment notification sent from an adjacent AP is received, and an example of determining whether or not the wireless cover area can be adjusted for the received area adjustment notification is shown.

  First, upon receiving an area adjustment notification from an adjacent AP (ST401: YES), the wireless area adjustment unit 18 requests terminal number information from the terminal number management unit 14, and from the table in FIG. Terminal number information is acquired (ST402). Therefore, the wireless area adjustment unit 18 determines whether or not the wireless cover area of the local station can be adjusted based on the area adjustment notification and the terminal number information of the local station (ST403), and if it can be adjusted (ST404: YES). The determination result is notified to the AP that has received the area adjustment notification (ST405). On the other hand, if, for example, an important terminal (such as a VIP terminal designated to be immovable to another AP) is connected, the wireless coverage area cannot be adjusted (ST404: NO), this is indicated in the area. The AP that has received the adjustment notification is notified (ST406). In this case, the AP that has received the notification that the wireless cover area cannot be adjusted can determine the adjustment of the wireless cover area based on the determination result and then send the area adjustment notification again. Then, according to the area adjustment notification from the adjacent AP, the wireless control unit 12 adjusts the transmission power to change the wireless cover area (ST407), and the wireless cover area adjustment operation ends.

  FIG. 11 is a schematic diagram illustrating an example of a state of the wireless cover area after adjustment in the wireless communication system illustrated in FIG. Here, when it is determined that the number of STAs performing communication in the management site 7 is small, the transmission power of AP2-AP4 is set to zero, and those radio cover areas 4-6 are extinguished while the radio covers to be extinguished In this case, the transmission power of AP1 is increased so as to compensate for the area 4-6, and the wireless cover area 3 is expanded to the entire management site 7. Accordingly, the STA 5 connected to the AP 2 and the STA 10 connected to the AP 4 can newly connect to the AP 1 to perform communication. Thereafter, the STA1, the STA5, and the STA10 can perform wireless communication in the management site 7 without the need for movement between base stations.

  Note that the adjustment of the wireless cover area of each AP is not limited to that shown in FIG. 11, and various changes can be made in consideration of the efficient operation of APs and communication quality in the wireless communication system 1. For example, the transmission power of AP2-AP4 is decreased to reduce the radio coverage area 4-6, while the radio coverage area 3 is increased by increasing the transmission power of AP1 so as to compensate for the reduced radio coverage area. It is also possible to configure so as to enlarge. Alternatively, the transmission power of AP3 and AP4 is set to zero, and the radio coverage areas 5 and 6 are extinguished, while the radio transmission areas 5 and 6 to be extinguished are increased to increase the transmission power of AP1 and AP2. A configuration in which the wireless cover areas 3 and 4 are enlarged is also possible.

  FIG. 12 is a sequence diagram showing a series of operations in the wireless communication system shown in FIG. Although the operation of AP1 is shown here, the same operation is possible for the other AP2-AP4.

  First, in the AP information management operation, when AP1 is activated, the information notification unit 15 notifies AP2-AP4 in the wireless communication system 1 of its own AP information. At this time, the AP information to be notified includes a request for AP information to AP2-AP4. Thereafter, the AP information notified by AP2-AP4 in response to the request is sent to the neighboring AP information management unit 16. It is received and managed as data in the adjacent AP information table (FIG. 5).

  Next, in the terminal number management operation, when the STA accesses the AP 1 via the wireless unit 11 and a normal connection is established, the wireless control unit 12 notifies the terminal connection management unit 13 of connection. The terminal connection management unit 13 manages the contents of the connection notification as data in the connection information table (FIG. 3). Therefore, the terminal connection management unit 13 notifies the terminal number management unit 14 of the connection status, and the terminal number management unit 14 connects the terminal number information based on the STA connection information from the terminal connection management unit 13. It is managed as data in the number statistics table (FIG. 4). The terminal number management unit 14 periodically notifies the information notification unit 15 of the terminal number information. The information notification unit 15 acquires the AP information of AP2-AP4 from the adjacent AP information management unit 16 (adjacent AP information table) in order to specify the notification destination of the terminal number information of the own station, and the AP2-AP4 Notifies the terminal number information of its own station. At this time, the notified terminal number information includes a request for the terminal number information for AP2-AP4. In response to the request, the terminal number information notified by AP2-AP4 respectively indicates the adjacent AP terminal number management. The data is received by the unit 17 and managed as data of the adjacent AP terminal number statistics table (FIG. 6).

  Next, in the area adjustment operation (1), when the terminal number management unit 14 determines that the number of STAs connected to its own station is small, it requests the wireless area adjustment unit 18 to adjust the wireless cover area. Therefore, the wireless area adjustment unit 18 acquires the latest terminal number information of AP2-AP4 from the adjacent AP terminal number management unit 17 (adjacent AP terminal number statistics table), and wirelessly covers AP2-AP4 in the management site 7. Adjust the area range. Further, the wireless area adjustment unit 18 acquires AP information of AP2-AP4 from the adjacent AP information management unit 16 (adjacent AP information table) in order to specify the notification destination of the area adjustment notification, and the AP2-AP4 Send area adjustment notification. Thereafter, the AP2-AP4 that has received the area adjustment notification notifies the AP that the area adjustment notification has been accepted, whereby the wireless cover area adjustment is completed. According to the adjustment result, in AP1, the wireless control unit 12 sends a power control notification to the wireless unit 11, and the transmission power of the wireless unit 11 is adjusted, whereby the wireless cover area is changed. In AP2-AP4 that has received the area adjustment notification, the wireless cover area is changed in the same manner as AP1.

  As an example of changing the area adjustment operation (1), the area adjustment operation (2) shown in FIG. 13 may be executed. In this area adjustment operation (2), AP1 receives an area adjustment notification from an adjacent AP (AP2, AP3 or AP4). Therefore, the wireless area adjustment unit 18 acquires the latest terminal number information from the terminal number management unit 14 (connected number statistics table). Subsequently, the wireless area adjustment unit 18 determines whether or not the wireless coverage area of the local station can be adjusted, and notifies the adjacent AP that has received the area adjustment notification of the determination result. After that, in AP1, according to the area adjustment notification, the wireless control unit 12 sends a power control notification to the wireless unit 11, and the transmission power of the wireless unit 11 is adjusted, so that the wireless cover area is changed. Also, in other AP2-AP4, the radio coverage area is changed as in AP1.

  Note that the area adjustment operation (1) and the area adjustment operation (2) are also applicable when the number of STAs communicating within the management site 7 increases again. In this case, the adjustment of the range of the wireless cover area reduces the wireless cover area (for example, the wireless cover area 3 in FIG. 11) that has been expanded among AP1 to AP4, while reducing or disappearing the wireless cover area. (For example, the wireless cover area 4-6 in FIG. 11) can be enlarged (generated). At this time, the adjustment of the range of the wireless cover area can be started when the number of connected STAs in any one of AP1 to AP4 becomes equal to or greater than the prescribed number.

  FIG. 14 is a schematic diagram showing a schematic configuration of a radio communication system according to the second embodiment of the present invention. This wireless communication system 101 has a configuration in which four wireless base stations (AP) AP5-AP8 are connected to each other via a LAN 102, and has a configuration substantially similar to that of the wireless communication system 1 shown in FIG. , AP5-AP8 is different in that a monitoring device 108 for controlling the communication operation is provided. AP5-AP8 has a predetermined wireless cover area (area in charge) 103-106, and controls connection from a plurality of wireless terminals (STA) STA1-STA10 to relay wireless communication. These wireless cover areas 103 to 106 are normally arranged so that wireless communication is possible in the entire management site (management area) 107 of the wireless communication system 101. Hereinafter, configurations that are not particularly referred to regarding the wireless communication system 101 are the same as those of the wireless communication system 1 illustrated in FIG. 1.

  15 is a functional block diagram showing a schematic configuration of the radio base station shown in FIG. Here, although the configuration of AP5 is shown, the same configuration is possible for other AP6-AP8. The AP 5 mainly includes a wireless unit 111, a wireless control unit 112, a terminal connection management unit 113, a terminal number management unit 114, a monitoring device interface unit 115, and a wired network control unit 119. Here, regarding the wireless unit 111, the wireless control unit 112, the terminal connection management unit 113, the terminal number management unit 114, and the wired network control unit 119, the wireless unit 11, the wireless control unit 12, and the terminal connection in the AP1 illustrated in FIG. It corresponds to the management unit 13, the terminal number management unit 14, and the wired network control unit 19, respectively, and has substantially the same function.

  The monitoring device interface unit 115 has an interface function with the monitoring device 108, and notifies the monitoring device 108 of information such as the number of terminals of the own station and AP information via the LAN 102. An instruction from the monitoring device 108 regarding the adjustment of the power is received, and a power control notification for changing the wireless cover area 103 is sent to the wireless control unit 112.

  FIG. 16 is a functional block diagram showing a schematic configuration of the monitoring apparatus shown in FIG. The monitoring device 108 mainly includes an AP control unit 121, an AP information management unit 122, a terminal number information management unit 123, and a wired network control unit 124.

  An AP control unit (communication adjustment unit, communication change unit) 121 controls the overall operation of AP 6 -AP 8 (hereinafter referred to as “all APs”) in the wireless communication system 101. In particular, the AP control unit 121 adjusts the range of the wireless coverage area in all APs in the wireless communication system 101, and controls power for instructing all APs to change the wireless coverage area based on the adjustment result. Notify about the command.

  The AP information management unit 122 manages AP information acquired from all APs via the LAN 2. The AP information management unit 122 stores the acquired AP information in a memory (not shown) as data of the adjacent AP information table. In the adjacent AP information table, similar to that shown in FIG. 5, an identifier for identifying each AP, an IP address indicating the location of each AP, a transmission power value indicating the setting of the radio unit of each AP, and Includes wireless channels.

  The terminal number information management unit (information acquisition unit) 123 manages the terminal number information acquired from all APs via the LAN 2. The terminal number information management unit 122 stores the acquired terminal number information in a memory (not shown) as data of the adjacent AP terminal number statistical table. This statistical table includes an identifier for identifying each AP, date, time, the number of connected devices, etc., as shown in FIG.

  The wired network control unit 124 controls communication with all APs via the LAN 102. That is, all the communication operations performed by the AP control unit 121, the AP information management unit 122, and the terminal number information management unit 123 for all APs are controlled by the wired network control unit 124.

  FIG. 17 is a flowchart showing the AP information management operation of the AP in the monitoring apparatus shown in FIG. First, when the monitoring device 108 is activated (ST701), the AP control unit 121 notifies the AP information request to all APs in the wireless communication system 101 (ST702). Upon receiving notification of AP information from all APs (ST703), AP information management section 122 stores the AP information in a predetermined memory as data in the information table similar to the adjacent AP information table shown in FIG. (ST704).

  Note that without sending a request for AP information from the monitoring device 108 to all APs as in ST702, AP information transmission timings are set in advance in all APs, and periodically transmitted from all APs according to the transmission timings. A configuration in which AP information is transmitted to the monitoring apparatus 108 is also possible.

FIG. 18 is a flowchart showing an operation for managing the number of connected APs in the monitoring apparatus shown in FIG. The AP control unit 121 periodically acquires AP information of all APs from the AP information management unit 122 (ST801), and when it is time to request the number of terminals (ST802: YES), A request for the number of terminals information is notified to the AP (ST803). Subsequently, when the AP information management unit 122 receives the terminal number information transmitted from each AP that has received the request for the terminal number information (ST804), the AP number management unit 122 displays the terminal number information shown in FIG. Information table data similar to the table is stored and managed in a predetermined memory (ST805)
Note that the transmission timing of the terminal number information is set in advance in all APs without notifying the terminal AP information request to all APs from the monitoring device 108 as in ST803, and is periodically transmitted from all APs according to the transmission timing. In other words, a configuration in which the number-of-terminals information is sent to the monitoring device 108 is also possible.

  FIG. 19 is a flowchart showing a first adjustment operation of the wireless cover area in the monitoring apparatus shown in FIG. Here, a case where the monitoring device determines the timing of adjustment of the wireless cover area is shown.

  First, if the terminal number information management unit 123 determines that the number of STAs connected to all APs (or a part of the APs) in the management site 107 is small (ST901: YES), the terminal number information management unit 123 determines to the AP control unit 121. Request to start predetermined power control (ST902). Therefore, AP control section 121 acquires AP information of all APs from AP information management section 122 (ST903), and notifies all APs of a command related to power control for changing the radio coverage area (ST904). After that, each AP that receives the command related to the power control adjusts the transmission power by the radio unit 111 according to the command, thereby changing the radio cover area (ST905).

  In the above operation, the AP control unit 121 can adjust the range of the radio coverage area of all APs in the same manner as the radio area adjustment unit 18 shown in FIG. A command related to power control can be notified.

  FIG. 20 is a flowchart showing a second adjustment operation of the wireless cover area in the monitoring apparatus shown in FIG. Here, a case where the timing for adjusting the wireless cover area is determined based on an area adjustment request from each AP is shown.

  First, upon receiving an area adjustment request from any AP (ST1001), the AP control unit 121 determines whether or not the number of STAs connected to all APs in the management site 107 by the terminal number information management unit 123 is small. Determine (ST1002). Therefore, if it is determined that the number of STAs is small, the AP control unit 121 is requested to start predetermined power control (ST1003). Subsequently, the AP control unit 121 acquires AP information of all APs from the AP information management unit 122 (ST1004), and notifies all APs of a command related to power control (ST1005). After that, each AP that has received the command related to the power control adjusts the transmission power by the radio unit 111 according to the command, so that the radio cover area is changed (ST1006).

  FIG. 21 is a schematic diagram illustrating an example of a state of the wireless cover area after adjustment in the wireless communication system illustrated in FIG. Here, when it is determined that the number of STAs performing communication within the management site 107 is small, the transmission power of the AP 6 to AP 8 is set to zero, and the radio coverage areas 104 to 106 are extinguished while the extinguished radio is used. In this example, the AP 5 transmission power is increased so that the cover area 104-106 is supplemented, and the wireless cover area 103 is expanded to the entire management site 107. Accordingly, the STA 5 connected to the AP 6 and the STA 10 connected to the AP 8 can newly connect to the AP 5 to perform communication. Thereafter, the STA1, the STA5, and the STA10 can perform wireless communication in the management site 107 without the need for movement between base stations.

  FIG. 22 is a sequence diagram showing a series of operations in the wireless communication system shown in FIG.

  First, in the AP information management operation, when the monitoring device 108 is activated, the AP control unit 121 notifies the AP5-AP8 of a request for AP information. In response to the request, the AP information transmitted by AP5-AP8 is received by the AP control unit 121 and managed in the same manner as the table of FIG.

  Next, in the terminal number management operation, the AP control unit 121 periodically requests the terminal number information from the AP5-AP8 while acquiring the AP information of the AP5-AP8 periodically from the AP information management unit 122. To do. In response to the request, the number-of-terminals information transmitted by AP5-AP8 is received by the number-of-AP terminal management unit 123 and managed in the same manner as the table of FIG.

  Next, in the area adjustment operation (1), when the terminal number information management unit 123 determines that the number of STAs connected to all the APs in the management site 107 is small, the AP control unit 121 performs predetermined power control. Request to start. Therefore, the AP control unit 121 acquires AP information of AP5-AP8 from the AP information management unit 122, and notifies the AP5-AP8 of a command related to power control. Thereafter, AP5 to AP8 that have received the command relating to the power control adjust the transmission power by the wireless unit 111 in accordance with the command, so that each wireless cover area 103-106 is changed.

  As a modification of the area adjustment operation (1), the area adjustment operation (2) shown in FIG. 23 can be used. In this area adjustment operation (2), first, upon receiving an area adjustment request from an AP (AP5, AP6, AP7 or AP8), the AP control unit 121 causes the terminal number information management unit 123 to execute AP5- in the management site 107. It is determined whether or not the number of STAs connected to the AP 8 is small. If it is determined that the number of STAs is small, the terminal number information management unit 123 requests the AP control unit 121 to start predetermined power control. Subsequently, the AP control unit 121 acquires the AP information of AP5-AP8 from the AP information management unit 122, and notifies the AP5-AP8 of a command related to power control. After that, AP5-AP8 that has received the command related to the power control adjusts the transmission power by the wireless unit 111 according to the received command related to power control, so that each wireless cover area 103-106 is changed.

  Although the present invention has been described in detail based on specific embodiments, these embodiments are merely examples, and the present invention is not limited to these embodiments. For example, the number and arrangement of radio base stations and radio terminals in the radio system are not limited to those shown in the above embodiment, and various changes can be made. Further, the change of the radio coverage area in each radio base station is not limited to that by adjusting the transmission power as in the above-described embodiment. For example, a directivity antenna is provided in the radio unit, and this function is used for directing. It can also be realized by adjusting the reach of the beam.

  A radio communication system radio base station, a monitoring apparatus, and a control method therefor according to the present invention are provided in a radio communication system having a predetermined management site covered by an assigned area adjacent to a plurality of radio base stations. When the number of wireless terminals that communicate with each other decreases, it is possible to operate each wireless base station efficiently while adjusting the range of the area in which each wireless base station is responsible, while preventing deterioration in communication quality Therefore, it is useful as a radio communication system radio base station, a monitoring device, and a control method thereof.

1 is a schematic diagram showing a schematic configuration of a wireless communication system according to a first embodiment of the present invention. Functional block diagram showing a schematic configuration of the radio base station of FIG. The figure which shows an example of the connection information table which manages the information of the radio | wireless terminal connected to the local station The figure which shows an example of the connection number statistics table which manages the number information of the radio | wireless terminal connected to the local station The figure which shows an example of the adjacent AP information table which manages AP information of adjacent AP. The figure which shows an example of the adjacent AP terminal number statistics table which manages the number information of the radio | wireless terminal connected to adjacent AP. FIG. 2 is a flowchart showing an AP information management operation in the radio base station of FIG. FIG. 2 is a flowchart showing the management operation of the number of connected wireless terminals in the wireless base station of FIG. The flowchart which shows the 1st adjustment operation of the radio | wireless cover area in the radio base station of FIG. The flowchart which shows the 2nd adjustment operation | movement of the radio | wireless cover area in the radio base station of FIG. Schematic diagram showing an example of the state of the wireless cover area after adjustment in the wireless communication system of FIG. The sequence diagram which shows a series of operation | movement in the radio | wireless communications system of FIG. FIG. 12 is a sequence diagram showing a modification example of the area adjustment operation of FIG. The schematic diagram which shows schematic structure of the radio | wireless communications system which concerns on the 2nd Embodiment of this invention. Functional block diagram showing a schematic configuration of the radio base station of FIG. 14 is a functional block diagram showing a schematic configuration of the monitoring device of FIG. FIG. 14 is a flowchart showing the AP information management operation of the AP in the monitoring apparatus of FIG. The flowchart which shows the management operation | movement of the number of connected APs in the monitoring apparatus of FIG. The flowchart which shows the 1st adjustment operation | movement of the radio | wireless cover area in the monitoring apparatus of FIG. The flowchart which shows the 2nd adjustment operation | movement of the radio | wireless cover area in the monitoring apparatus of FIG. The schematic diagram which shows an example of the state of the radio | wireless cover area after adjustment in the radio | wireless communications system of FIG. FIG. 14 is a sequence diagram showing a series of operations in the wireless communication system of FIG. FIG. 22 is a sequence diagram showing a modification example of the area adjustment operation of FIG.

Explanation of symbols

1 Wireless communication system 3-6 Wireless coverage area (area in charge)
7, 107 Management site (management area)
14 Terminal number management unit (first connection management means)
17 Adjacent AP terminal number management unit (second connection management means)
18 Wireless area adjustment section (responsible area adjustment means, responsible area change means)
121 AP control unit (communication adjustment means, communication change means)
123 Number-of-terminals information management unit (information acquisition means)
AP1-AP8 wireless base station STA1-STA10 wireless terminal

Claims (13)

A wireless communication system having a predetermined management area covered by a responsible area arranged adjacent to each other of a plurality of wireless base stations,
At least one of the plurality of radio base stations is
First connection management means for acquiring information on the number of connected wireless terminals in the own station;
Second connection management means for acquiring information on the number of connected wireless terminals in each wireless base station other than the own station;
In accordance with the information on the number of connected wireless terminals acquired by the first and second connection management means, the assigned area of any one of the plurality of wireless base stations is reduced or eliminated, while the reduction Or, the assigned area adjustment means for adjusting the range of each assigned assigned area by expanding the assigned area of any other radio base station to supplement the assigned area to be extinguished,
Based on the adjustment result of the assigned area adjustment means, the assigned area changing means for changing the assigned area of each radio base station other than the assigned station is provided. Wireless communication system.   The assigned area changing means adjusts the transmission power so as to change the assigned area of the own station, and adjusts each transmitted power so as to change the assigned area in each radio base station other than the own station. The wireless communication system according to claim 1.   The service area adjustment unit determines a radio base station that reduces, disappears, or expands the service area based on a priority set in advance for the plurality of radio base stations. Wireless communication system.   The assigned area adjustment means starts adjustment of the range of each assigned area when the number of connected wireless terminals of any one of the plurality of wireless base stations is equal to or less than a specified number. The wireless communication system according to claim 1.   The plurality of radio base stations include a predetermined radio base station capable of expanding a service area over the entire management area, and the service area adjustment unit includes all radio base stations other than the predetermined radio base station. The range of each of the assigned areas is adjusted so that the assigned area of the station is extinguished while the assigned area of the predetermined radio base station is expanded on the assigned assigned area. Wireless communication system. The assigned area changing means instructs each radio base station other than the own station to change the assigned area,
Upon receiving an instruction to change the assigned area, each radio base station other than the local station determines whether the assigned area can be changed, and determines the determination result of the determination means in the assigned area. The wireless communication system according to claim 1, further comprising notification means for notifying a wireless base station that has received a change instruction. A wireless communication system having a predetermined management area covered by a responsible area arranged adjacent to each other of a plurality of wireless base stations,
Information acquisition means for acquiring information on the number of connected wireless terminals in the plurality of wireless base stations,
Depending on the information on the number of connected wireless terminals acquired by the information acquisition means, the area in charge of any one of the plurality of wireless base stations is reduced or eliminated, while the area to be reduced or eliminated is supplemented. Communication adjustment means for adjusting the range of each assigned area arranged adjacently by enlarging the assigned area of any other radio base station,
A wireless communication system, comprising: a communication changing unit that causes the plurality of wireless base stations to change a responsible area based on an adjustment result of the communication adjusting unit.   The communication adjustment means adjusts the range of each assigned area arranged adjacent to each other when an adjustment request is received by any of the radio base stations, and the communication change means sets the adjustment result of the communication adjustment means 8. The radio communication system according to claim 7, wherein the plurality of radio base stations are caused to change a responsible area based on the radio base station. A radio base station that is arranged adjacent to another radio base station and covers an area in charge of radio allocated to itself,
First connection management means for acquiring information on the number of connected wireless terminals in the own station;
Second connection management means for acquiring information on the number of connected wireless terminals in each wireless base station other than the own station;
Depending on the information of the number of connected wireless terminals acquired by the first and second connection management means, the assigned area of the own station or any other wireless base station is reduced or eliminated, while the reduction or elimination is performed. A charge area adjustment means for adjusting the range of each charge area of the adjacent radio base station by expanding the charge area of the own station or any other radio base station so as to supplement the charge area to be performed;
Based on the adjustment result of the assigned area adjustment means, if it is necessary to change the assigned area of the own station, the assigned area of the own station is changed by controlling the power of the own station, and other radio base stations other than the own station A radio base station, comprising: a responsible area changing means for causing a corresponding radio base station to change a responsible area when a change is necessary. A monitoring device connected to a plurality of wireless base stations via a network,
Information acquisition means for acquiring information on the number of connected wireless terminals in the plurality of wireless base stations,
Depending on the information on the number of connected wireless terminals acquired by the information acquisition means, the area in charge of any one of the plurality of wireless base stations is reduced or eliminated, while the area to be reduced or eliminated is supplemented. Communication adjustment means for adjusting the range of each assigned area of the adjacent radio base station by enlarging the assigned area of any other radio base station,
A monitoring apparatus comprising: a communication changing unit that causes the plurality of radio base stations to change a responsible area based on an adjustment result of the communication adjusting unit. A wireless base station that is connected to a monitoring device via a network and covers a radio area assigned adjacent to the other wireless base station and allocated to the own station,
Information notification means for notifying the monitoring device of the number of connected wireless terminals connected to the own station;
A radio base station that changes the assigned area by controlling the power of the own station when instructed by the monitoring apparatus to change the assigned area. A control method of a radio communication system having a predetermined management area covered by a responsible area arranged adjacent to each other of a plurality of radio base stations,
In at least one of the plurality of radio base stations,
A first connection management step of acquiring information on the number of connected wireless terminals in the own station;
A second connection management step of acquiring information on the number of connected wireless terminals in each wireless base station other than the own station;
In accordance with the information on the number of connected wireless terminals acquired in the first and second connection management steps, the area in charge of any one of the plurality of wireless base stations is reduced or eliminated while the reduction is performed. Or an assigned area adjustment step for adjusting the range of each assigned assigned area by expanding the assigned area of any other radio base station so as to compensate for the assigned assigned area;
Based on the adjustment result of the assigned area adjustment step, the transmission power is adjusted to change the assigned area of the own station, and each transmitted power is adjusted to change the assigned area in each radio base station other than the own station. A control method for a wireless communication system, comprising: executing a responsible area changing step. A control method of a radio communication system having a predetermined management area covered by a responsible area arranged adjacent to each other of a plurality of radio base stations,
Information acquisition step for acquiring information on the number of connected wireless terminals in the plurality of wireless base stations,
Depending on the information on the number of connected wireless terminals acquired in the information acquisition step, the area in charge of any one of the plurality of wireless base stations is reduced or eliminated, while the area to be reduced or eliminated is supplemented. A communication adjustment step of adjusting the range of each assigned area arranged adjacently by expanding the assigned area of any other radio base station,
A control method for a radio communication system, comprising: a communication change step of adjusting each transmission power to change a region assigned to each of the plurality of radio base stations based on an adjustment result in the communication adjustment step.

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