JP6276577B2 - Communication control system and communication control method - Google Patents

Description

  The present invention relates to wireless communication technology.

  In order to respond to the increase in frequency demand accompanying the progress of wireless broadband, it is desired to use the frequency that makes more effective and efficient use of tight radio waves. White space use is one of the advanced use of frequencies, and the frequency assigned to a specific use such as broadcasting or communication is not affected by the geographical and temporal conditions in order to affect the current system. It can be used for other purposes. Users of the current system are referred to as primary users, and users other than primary users are referred to as secondary users.

  In geographical conditions, the secondary user grasps the service area of the primary user using a database that manages radio station information, frequency allocation, and geographical information, and confirms that there is a sufficient separation distance. . Also, in terms of time, the secondary user determines the frequency that can be used in the white space by linking the spectrum sensing that grasps the radio wave condition that changes every moment according to the position and usage status of the radio station and the database. Non-Patent Document 1 discloses conditions for using white space using spectrum sensing and a database.

  FIG. 5 shows an example of the area formation of the secondary system in white space utilization and the configuration of the white space utilization system. The base station 10 includes an antenna 11, a SW (switch) 12, a sensing unit 13, a control unit 14, a transmission / reception unit 15, and an NW (network) interface 16. The sensing unit 13 of the base station 10 periodically detects the radio wave intensity at the usage frequency of the primary system. The terminal 20 includes an antenna 21, a SW 22, a sensing unit 23, a control unit 24 and a transmission / reception unit 25. The sensing unit 13 transmits the detection result to the data storage unit 43 of the NW control unit 40 via the NW interface 16 and the core NW 30.

  The NW control unit 40 includes an NW interface 41, a data management unit 42, a data storage unit 43, a data analysis unit 44, and a control unit 45. In the data management unit 42, carrier information and radio wave characteristics of the primary system are registered. The data analysis unit 44 compares the radio wave data in the data storage unit 43 with the frequency information of the existing system in the data management unit 42 to estimate whether the primary system is used, and determines whether the secondary system can be used. The base station 10 of the secondary system inquires of the data management unit 42 about frequencies that can be used for white space. The data management unit 42 updates the frequency band available for white space every time the data storage unit 43 is updated as a result of spectrum sensing, and responds to an inquiry from the base station 10. Based on the answer from the data management unit 42, the base station 10 communicates with the terminal 20 by setting a frequency that can be used for white space.

  Here, the radio wave closed space is one of techniques for improving frequency use efficiency by performing frequency sharing not only between the primary user and the secondary user but also between the secondary users. The radio wave closed space is characterized in that the amount of interference leaking out of the wireless usage boundary set by estimating the amount of interference based on site-specific propagation analysis is suppressed to an allowable value or less. Thereby, a frequency repetition distance can be shortened and frequency utilization efficiency improves (refer nonpatent literature 2).

  FIG. 6 is a diagram illustrating a configuration example of a radio wave closed space system. The access points 100-1 to 100n (n is an arbitrary integer) periodically transmits a beacon according to an instruction from the control unit 120, and the other access points 100 and all terminals 200-1 to 200-m (m is an arbitrary number). Is an RSSI (Received Signal Strength Indication) at each of the carrier sense units (150, 240). The measured RSSI is added with a measurement time stamp and stored in the data storage unit 440 of the NW control unit 400. The NW control unit 400 extracts RSSI having the same time stamp as the transmission time of each access point and each terminal from the stored RSSI data, and calculates an interference amount in consideration of transmission power and antenna gain. As a result, the RSSI control unit 400 grasps the amount of interference for all combinations of access points and terminals.

  FIG. 7 is a flowchart showing an example of a flow of processing executed in the radio wave closed space system shown in FIG. Hereinafter, when the access point is not distinguished, it will be simply referred to as the access point 100. Further, when it is not distinguished which terminal is the terminal, the terminal 200 will be simply referred to.

First, each terminal 200 selects an access point 100 that connects the access point 100 having the maximum interference amount from the interference amounts in all combinations (step S100).
Next, each access point 100 resets the transmission power so as to be an allowable interference amount with respect to all terminals other than the connected terminal and other access points 100 (step S110). Each access point 100, receives power by connecting with the transmission power re-set becomes more minimum received power, determines whether communication is possible terminal 200 is present (step S120). If the terminal 200 to be higher minimum received power does not exist (Step S120-NO), since the radio wave closed space is not formed normally, does not perform communication using the inter-radio closed space (step S130).

On the other hand, if the minimum or the received power of the terminal is present (step S120-YES), it is notified to the closed space analyzing unit 480 of the NW control section 400. In this case, the closed space analysis unit 480 of the NW control unit 400 determines whether or not the interference amount is equal to or less than the allowable interference amount at the radio wave usage boundary (step S140). When the interference amount is not less than or equal to the allowable interference amount (step S140-NO), the closed space control unit 470 of the NW control unit 400 causes the control unit 120 of the access point 100 to be equal to or less than the allowable interference amount at the usage boundary. The transmission power of the transmission unit 130 is reset via (step S150). Then, Step S120 is executed in the access point 100, and the processes of Steps S120, S140, and S150 are repeated until the interference amount at the use boundary becomes equal to or less than the allowable interference amount (Step S140-YES).
If the amount of interference is less than the allowable interference at the usage boundary, the radio wave closed space (indicated by closed space areas # 1 and # 2 in FIG. 6) is formed normally (step S160), and the access point 100 and the terminal 200 are closed. Perform communication using. Thus, frequency sharing between secondary users becomes possible by estimating the amount of interference and transmitting power control.

Harada et al., “R & D for New Broadband Access in White Space”, IEICE Technical Report, SR2011-76, pp.199-206, 2013.10. Katayama et al., "Proposal of closed radio wave system using user-centric wireless network", 2013 UEC, B-17-37, 2013.3.

  However, in the specification of the separation distance between the primary user and the secondary user in Non-Patent Document 1, an allowable interference amount considering the site-general propagation equation and propagation fluctuation obtained experimentally is applied. Depending on the case, the separation distance may be longer than necessary, and the frequency utilization efficiency may be reduced. In Non-Patent Document 2, since the transmission power is controlled so as not to give interference between access points, the area radius is approximately ½ of the access point interval. However, there is a problem that the communication area is narrowed and the number of terminals to be accommodated is reduced.

  In view of the above circumstances, an object of the present invention is to provide a technique capable of improving frequency use efficiency and suppressing a decrease in terminal coverage even when access point intervals are close.

One aspect of the present invention is a communication control system including a plurality of access points that can communicate wirelessly with a terminal, and a network control unit that can communicate with the plurality of access points. An acquisition unit that acquires the amount of interference caused by wireless communication, and an interference amount acquired by the acquisition unit, and grouping access points whose mutual interference amount is equal to or greater than a threshold value and considering it as one access point with recalculating the interference amount, the interference amount by the recalculation of the grouped the access point to connect said terminal to the maximum access points, grouped the access point is connected to the self closed space determined for the terminal and other of the access point, the transmission power so that the interference amount becomes less than a specified value An analysis unit, a time synchronization unit that assists the grouped access points to transmit the same signal at a synchronized timing, and transmission power of the access point based on transmission power determined by the closed space analysis unit a closed space control unit for controlling a communication control system Ru comprising a.

One aspect of the present invention is a communication control system including a plurality of access points that can communicate wirelessly with a terminal, and a network control unit that can communicate with the plurality of access points. An acquisition unit that acquires the amount of interference caused by wireless communication, and an interference amount acquired by the acquisition unit, and grouping access points whose mutual interference amount is equal to or greater than a threshold value and considering it as one access point together recalculate the amount of interference, when the amount of interference to the recalculation of the grouped the access point is connected is the terminal to the maximum access points, it grouped the access point to the desired terminal On the other hand, the transmission signal is set so that the index value indicating the reception strength is maximized and the received power is minimized for other terminals. A closed space analysis unit for determining amplitude and phase, a time synchronization unit for supporting the grouped access points to transmit the same signal at a synchronized timing, and the amplitude determined by the closed space analysis unit a closed space control unit for controlling the access point based on the phase, a communication control system Ru comprising a.

  One aspect of the present invention is the communication control system described above, wherein the closed space analysis unit is configured so that the number of accommodated terminals or the accommodation rate of the grouped access points satisfies a setting condition. Perform grouping.

One aspect of the present invention is a communication control system including a plurality of access points capable of wirelessly communicating with a terminal and a network control unit capable of communicating with the plurality of access points, wherein the plurality of access points or the network control unit Refers to the process of acquiring the amount of interference due to wireless communication between the terminal and the access point, and refers to the acquired amount of interference, extracts the access points whose mutual interference amount is equal to or greater than a threshold, and extracts the extracted together to recalculate the amount of interference when regarded as one access point to group access point, if the amount of interference to the recalculation of the grouped the access point is connected is the terminal to the maximum of the access point The grouped access points are connected to the terminal and other previous To the access point, the process of determining the transmission power so that the interference amount becomes less than the specified value, a process of the grouped access point help them transmitted at the timing synchronized with the same signal, the together based on the determined transmission power for controlling transmission power of the access point, the grouped access point is a communication control method for performing a process of controlling to transmit at a timing in synchronization with the same signal .

One aspect of the present invention is a communication control system including a plurality of access points capable of wirelessly communicating with a terminal and a network control unit capable of communicating with the plurality of access points, wherein the plurality of access points or the network control unit However, a process of acquiring an interference amount due to wireless communication between the terminal and the access point, and referring to the acquired interference amount, grouping access points whose mutual interference amount is a threshold value or more, together to recalculate the amount of interference when regarded as point, when the amount of interference to the recalculation of the grouped the access point is connected is the terminal to the maximum access points, grouped the access point the index value indicating the reception intensity becomes maximum with respect to the desired terminal, the other terminal Thus, the process of determining the amplitude and phase of the transmission signal so that the reception power is minimized, the process of assisting the grouped access points to transmit the same signal at a synchronized timing, and the determination amplitude and a process for controlling the access point based on the phase that is a communication control method for performing.

  One aspect of the present invention is the communication control method described above, wherein the plurality of access points or the network control unit is configured such that the number of accommodated terminals or the accommodation rate of the grouped access points satisfies a setting condition. The access points are grouped.

  According to the present invention, even when access point intervals are close, it is possible to improve frequency utilization efficiency and suppress a decrease in terminal coverage.

It is a figure showing an example of composition of communication control system 1 concerning a 1st embodiment. It is a flowchart which shows an example of the flow of the process performed by the communication control system 1 which concerns on 1st Embodiment. It is the figure which showed the structural example of the communication control system 2 which concerns on 2nd Embodiment. It is a flowchart which shows an example of the flow of the process performed by the communication control system 2 which concerns on 2nd Embodiment. It is a figure which shows the example of a structure of the area formation of the secondary system in white space utilization, and a white space utilization system. It is the figure which showed the example of a structure of the electromagnetic wave closed space system. It is a flowchart which shows an example of the flow of the process performed in the electromagnetic wave closed space system shown in FIG.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a configuration example of a communication control system 1 according to the first embodiment. The communication control system 1 includes a plurality of access points 100-1 to 100-n (n is an arbitrary integer), a plurality of terminals 200-1 to 200-m, and an NW control unit 400. Hereinafter, when the access point is not distinguished, it will be simply referred to as the access point 100. Further, when it is not distinguished which terminal is the terminal, the terminal 200 will be simply referred to. Each access point 100 and NW control unit 400 are connected via a core NW 300. The core network 300 is formed of an optical fiber and can perform high-speed and large-capacity communication.

  The access point 100 includes an NW interface 110, a control unit 120, a transmission unit 130, a SW 140, a carrier sense unit 150, a reception unit 160, an antenna 170, and a time synchronization unit 180.

  The NW interface 110 is connected to the core network 300 via an optical fiber. The control unit 120 functions by executing a program stored in a storage unit (not shown), and comprehensively controls processing of the access point 100. The transmission unit 130 performs processing such as modulation on the signal input from the control unit 120, and controls the SW 140 and the antenna 170 so as to transmit the processed signal. Carrier sense section 150 measures RSSI for beacons received from other access points 100. The RSSI measured by the carrier sense unit 150 is added with a measurement time stamp, transmitted to the NW control unit 400 via the NW interface 110 and the core NW 300, and stored in the data storage unit 440 of the NW control unit 400. . The receiving unit 160 performs processing such as demodulation on the signals received by the SW 140 and the antenna 170 and outputs the processed signals to the control unit 120. The time synchronizer 180 cooperates with the time synchronizer 500 of the NW controller 400, and sends the transmitter 130 and the like so as to transmit and receive the same signal as the other access points 100 grouped as described later at the same timing. Control.

  The terminal 200 includes an upper layer 210, a control unit 220, a transmission unit 230, a carrier sense unit 240, a reception unit 250, a SW 260, and an antenna 270.

  The upper layer 210 outputs transmission data to the control unit 220 together with the transmission request when a transmission request is generated by an operation of an application by the user. In addition, the upper layer 210 transmits data input from the control unit 220 to an application or the like. The control unit 220 functions by executing a program stored in a storage unit (not shown), and comprehensively controls processing of the terminal 200. The transmission unit 230 performs processing such as modulation on the signal input from the control unit 220, and controls the SW 260 and the antenna 270 so as to transmit the processed signal. The carrier sense unit 240 measures RSSI for the beacon received from the access point 100. The RSSI measured by the carrier sense unit 240 is added with a measurement time stamp, transmitted to the NW control unit 400 via the access point 100 and the core NW 300, and stored in the data storage unit 440 of the NW control unit 400. . The receiving unit 250 performs processing such as demodulation on the signal received by the SW 260 and the antenna 270 and outputs the result to the control unit 220.

  The NW control unit 400 includes a database 410, an NW interface 420, a demodulation unit 430, a data storage unit 440, a modulation unit 450, a control unit 460, a closed space control unit 470, a closed space analysis unit 480, An upper layer 490 and a time synchronization unit 500 are provided.

  The database 410 is constructed on a storage device such as an HDD (Hard Disk Drive) or a flash memory. The database 410 stores information such as the performance and position of each access point 100. The NW interface 420 is connected to the core network 300 via an optical fiber. Demodulation section 430 demodulates the signal received from each access point 100 via NW interface 420 and outputs the demodulated signal to higher layer 490. The data storage unit 440 stores data such as RSSI received from the access point 100 or the terminal 200. Modulating section 450 modulates a signal to be transmitted to each access point 100 via NW interface 420. The control unit 460 functions by executing a program stored in a storage unit (not shown), and comprehensively controls the processing of the NW control unit 400.

  The closed space control unit 470 controls signal transmission power, antenna directivity, and the like at each access point 100 to set a boundary of the radio wave closed space. The closed space analysis unit 480 performs grouping processing of the access points 100 based on the amount of interference, as will be described below. The upper layer 490 performs processing related to the operating system and applications. The time synchronization unit 500 cooperates with the time synchronization unit 180 of the access point 100 to support the access point 100 so that the same signal as that of the other access point 100 can be transmitted and received at the same timing.

  FIG. 2 is a flowchart illustrating an example of a flow of processing executed by the communication control system 1 according to the first embodiment. As a premise of such processing, as described above, the NW control unit 400 grasps the amount of interference in all combinations of the plurality of access points 100 and the plurality of terminals 200 that can communicate with each other.

  First, the closed space analysis unit 480 of the NW control unit 400 extracts a plurality of access points 100 that are estimated to be close to each other because the mutual interference amount is equal to or greater than a predetermined value. And defined as grouped access points (step S200). The access points 100 grouped in this way are linked to each other by the time synchronization unit 180 and the time synchronization unit 500 of the NW control unit 400, so that NTP (Network Time Protocol), PTP (Precise Time Protocol), etc. The time frequency synchronization is established by the protocol, and the same signal is transmitted and received at the same timing.

  Next, the closed space analysis unit 480 of the NW control unit 400 invalidates the interference between the access points 100 grouped in step S200, regards the grouped access points 100 as one access point 100, and sets the access point 100. And the amount of interference between the access point 100 and the terminal 200 is recalculated (step S210).

  Next, each terminal 200 selects the access point 100 having the maximum interference amount recalculated in step S210 as the connection destination access point 100 (step S220).

Next, each access point 100 resets the transmission power for all terminals 200 and other access points 100 connected to the access point 100 so as to be equal to or less than the allowable interference amount (step S230). Each access point 100, receives power by connecting with the transmission power re-set becomes more minimum received power, determines whether it is possible terminal 200 is present to perform the communication (step S240 ). If the terminal 200 to be higher minimum received power does not exist (Step S240-NO), since the radio wave closed space is not formed normally, does not perform communication using the inter-radio closed space (step S250).

On the other hand, if the minimum reception power or more terminals 200 is present (step S240-YES), it is notified to the closed space analyzing unit 480 of the NW control section 400. In this case, the closed space analysis unit 480 of the NW control unit 400 determines whether or not the interference amount is equal to or less than the allowable interference amount at the radio wave usage boundary (step S260). When the interference amount is not less than or equal to the allowable interference amount (step S260—NO), the closed space control unit 470 of the NW control unit 400 causes the control unit 120 of the access point 100 to be equal to or less than the allowable interference amount at the usage boundary. The transmission power of the transmission unit 130 is reset via (step S270). Then, step S240 is executed in the access point 100, and the processes of steps S240, S260, and S270 are repeated until the interference amount at the use boundary becomes equal to or less than the allowable interference amount (step S260—YES).

  If the amount of interference is equal to or less than the allowable interference at the usage boundary, the radio wave closed space (indicated by the closed space region # 3 in the figure) is normally formed (step S280). In this case, the closed space analysis unit 480 of the NW control unit 400 determines whether or not the number of terminals 200 accommodated in the grouped access points 100 is greater than or equal to a set value (step S290). When the accommodated number is less than the set value (step S290—NO), the closed space analysis unit 480 of the NW control unit 400 resets the threshold of the mutual interference amount between the access points 100 for grouping. (Step S300), the access point 100 is notified. Thereafter, the processing after step S200 is executed. On the other hand, when the accommodation number is equal to or larger than the set value (step S290—YES), the access point 100 and the terminal 200 perform communication using the radio wave closed space. Thus, frequency sharing between secondary users becomes possible by estimating the amount of interference and transmitting power control. In step S290, “accommodation rate” may be compared with a set value instead of “accommodation number”.

  According to the communication control system 1 and the communication control method of the present embodiment described above, the access points 100 whose mutual interference amount is equal to or greater than the threshold are extracted, and the number of terminals 200 accommodated in the extracted access points 100 satisfies the setting condition. The amount of interference is calculated when the access point 100 is grouped to satisfy one access point 100 and the calculated interference amount is equal to or less than a specified value. Since the same signal is transmitted at the synchronized timing with the determined transmission power, even when the access points 100 are close to each other, the frequency utilization efficiency is improved and the terminal coverage is not reduced. A radio wave closed space can be provided.

  Note that the location of the subject of each process described in FIG. 2 is merely an example, and the subject of the process is appropriately replaced, for example, such that the access point 100 includes the closed space control unit 470 and the closed space analysis unit 48. It doesn't matter.

[Second Embodiment]
The second embodiment of the present invention will be described below with reference to the drawings. FIG. 3 is a diagram illustrating a configuration example of the communication control system 2 according to the second embodiment. Compared to the first embodiment, in the communication control system 2 according to the second embodiment, the access point 100 includes a channel information acquisition unit 190 instead of the carrier sense unit 150, and the terminal 200 replaces the carrier sense unit 240. The channel information acquisition unit 280 is different. Hereinafter, the functions common to the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  The channel information acquisition unit 190 and the channel information acquisition unit 280 generate channel information indicating channel states in communication between the terminal 200 and the access point 100 and between the access points 100, and transmit the channel information to the NW control unit 400.

  FIG. 4 is a flowchart illustrating an example of a flow of processing executed by the communication control system 2 according to the second embodiment. As a premise of such processing, as described above, the NW control unit 400 grasps channel states in all combinations of a plurality of access points 100 and a plurality of terminals 200 that can communicate with each other, and The amount of interference can be grasped based on this.

  First, the closed space analysis unit 480 of the NW control unit 400 extracts a plurality of access points 100 that are estimated to be close to each other because the mutual interference amount is equal to or greater than a predetermined value. And defined as grouped access points (step S200). The access points 100 grouped in this manner establish time-frequency synchronization by a protocol such as NTP or PTP by the cooperation of the time synchronization unit 180 and the time synchronization unit 500 of the NW control unit 400, and the same. Are transmitted and received at the same timing.

  Next, the closed space analysis unit 480 of the NW control unit 400 invalidates the interference between the access points 100 grouped in step S200, regards the grouped access points 100 as one access point 100, and sets the access point 100. And the amount of interference between the access point 100 and the terminal 200 is recalculated (step S210).

  Next, each terminal 200 selects the access point 100 having the maximum interference amount recalculated in step S210 as the connection destination access point 100 (step S220).

Next, the closed space control unit 470 of the NW control unit 400 or the grouped access point 100 transmits the received SINR (Signal-to-to-signal) to the desired terminal 200 when the transmission signal of the grouped access point 100 is received. Interference-plus-Noise Ratio) is maximized, the received power is such that the minimum, to set the amplitude and phase of the transmission signal to the terminal 200 other than it (step S310). SINR is an example of “an index value indicating reception strength”. Further, “desired terminal 200” means a terminal 200 that is scheduled to communicate with the access point 100 using a radio wave closed space.

Each access point 100 determines whether the received power by connecting at a set amplitude and phase becomes higher minimum received power, it is desired terminal 200 is present capable of performing communication ( Step S240). If desired the terminal 200 to be higher minimum received power does not exist (Step S240-NO), since the radio wave closed space is not formed normally, does not perform communication using the inter-radio closed space (step S250).

On the other hand, if the desired terminal 200 over the minimum received power is present (step S240-YES), it is notified to the closed space analyzing unit 480 of the NW control section 400. In this case, the closed space analysis unit 480 of the NW control unit 400 determines whether or not the interference amount is equal to or less than the allowable interference amount at the radio wave usage boundary (step S260). When the interference amount is not less than or equal to the allowable interference amount (step S260—NO), the closed space control unit 470 of the NW control unit 400 causes the control unit 120 of the access point 100 to be equal to or less than the allowable interference amount at the usage boundary. The transmission power of the transmission unit 130 is reset via (step S270). Then, step S240 is executed in the access point 100, and the processes of steps S240, S260, and S270 are repeated until the interference amount at the use boundary becomes equal to or less than the allowable interference amount (step S260—YES).

  If the amount of interference is equal to or less than the allowable interference at the usage boundary, the radio wave closed space (indicated by the closed space region # 3 in the figure) is normally formed (step S280). In this case, the closed space analysis unit 480 of the NW control unit 400 determines whether or not the number of terminals 200 accommodated in the grouped access points 100 is greater than or equal to a set value (step S290). When the accommodated number is less than the set value (step S290—NO), the closed space analysis unit 480 of the NW control unit 400 resets the threshold of the mutual interference amount between the access points 100 for grouping. (Step S300), the access point 100 is notified. Thereafter, the processing after step S200 is executed. On the other hand, when the accommodation number is equal to or larger than the set value (step S290—YES), the access point 100 and the terminal 200 perform communication using the radio wave closed space. Thus, frequency sharing between secondary users becomes possible by estimating the amount of interference and transmitting power control. In step S290, “accommodation rate” may be compared with a set value instead of “accommodation number”.

According to the communication control system 2 and the communication control method of the present embodiment described above, the access points 100 whose mutual interference amount is equal to or greater than the threshold are extracted, and the number of terminals 200 accommodated in the extracted access points 100 satisfies the setting condition. In addition to calculating the amount of interference when grouped to meet one access point 100, the transmission signal of the grouped access point 100 has the maximum received SINR for the desired terminal, otherwise for the terminal to receive power is minimum, and determines the amplitude and phase of the transmission signal, grouped access point transmits at a timing synchronized with the same signal at the determined amplitude and phase Therefore, even when the access points 100 are close to each other, the frequency utilization efficiency is improved and the terminal Storage ratio can be provided between the waves closed space does not decrease.

  Note that the location of the main body of each process described with reference to FIG. 4 is merely an example, and the main body of the process is appropriately switched such that the access point 100 includes the closed space control unit 470 and the closed space analysis unit 48, for example. It doesn't matter.

The access point 100, the terminal 200, and the NW control unit 400 in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed. Note that the “computer system” herein includes an OS (Operating System) and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client in that case may be included and a program held for a certain period of time. Further, the program may be a program for realizing a part of the above-described functions, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system. You may implement | achieve using programmable logic devices, such as FPGA (Field Programmable Gate Array).
The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Primary user, 2 ... Secondary user, 10 ... Base station, 11, 21, 170, 270 ... Antenna, 12, 22, 140, 260 ... SW, 13, 23 ... Sensing part 14, 24, 45, 120, 220, 460 ... control unit, 15, 25 ... transmission / reception unit, 16, 41, 110, 420 ... NW interface, 20, 200 ... terminal, 30 ... core NW, 40, 400 ... NW control unit, 42 ... Data management unit, 43, 440 ... Data storage unit, 44 ... Data analysis unit, 100 ... Access point, 130,230 ... Transmission unit, 150,240 ... Carrier sense unit, 160,250 ... Reception unit, 210 ... Upper layer, 410 ... Database, 430 ... Demodulator, 450 ... Modulator, 470 ... Closed space controller, 480 ... Closed space analyzer, 190, 2 0 ... channel information acquisition unit

Claims (6)

A communication control system including a plurality of access points capable of communicating with a terminal wirelessly and a network control unit capable of communicating with the plurality of access points,
An acquisition unit for acquiring an interference amount resulting from wireless communication between the terminal and the access point;
Referring to interference amount acquired by the acquiring unit, as well as re-calculates an interference amount when regarded as one access point by grouping access points interfering amount over the threshold of each other, it grouped the access If the amount of interference to the recalculation of points to connect the terminal to the maximum access points, it grouped the access point to the terminal and another one of the access points connected to the self-interference amount a closed space analyzing unit that determines transmission power such but equal to or less than a specified value,
A time synchronization unit that assists the grouped access points to transmit the same signal in synchronized timing;
A closed space control unit for controlling the transmission power of the access point based on the transmission power determined by the closed space analysis unit;
Communication control system Ru equipped with. A communication control system including a plurality of access points capable of communicating with a terminal wirelessly and a network control unit capable of communicating with the plurality of access points,
An acquisition unit for acquiring an interference amount resulting from wireless communication between the terminal and the access point;
Refer to the interference amount acquired by the acquisition unit, recalculate the interference amount when the access points whose mutual interference amount is equal to or greater than the threshold value are considered as one access point, and the grouped access If the amount of interference to the recalculation of points to connect the terminal to the maximum access points, grouped the access point index value indicating the reception intensity becomes maximum with respect to the desired terminal, it A closed space analysis unit that determines the amplitude and phase of the transmission signal so that the received power is minimized for terminals other than
A time synchronization unit that assists the grouped access points to transmit the same signal in synchronized timing;
A closed space control unit for controlling the access point based on the amplitude and phase determined by the closed space analysis unit;
Communication control system Ru equipped with. The closed space analysis unit resets the threshold so that the number of terminals accommodated or the rate of accommodation of the grouped access points satisfies a setting condition, and groups the access points.
The communication control system according to claim 1 or 2. In a communication control system including a plurality of access points that can communicate with a terminal wirelessly and a network control unit capable of communicating with the plurality of access points,
The plurality of access points or the network control unit,
Processing for acquiring an interference amount resulting from wireless communication between the terminal and the access point;
Referring to the obtained amount of interference, with the amount of interference to each other extracts the access point equal to or higher than the threshold, to recalculate the amount of interference when regarded as one access point by grouping the access point the extracted, If the amount of interference to the recalculation of the grouped the access point the terminal connects to the maximum access points, grouped the access point, the terminal and the other of said access point to connect to the self In contrast, a process for determining transmission power so that the amount of interference is less than or equal to a specified value;
A process for assisting the grouped access points to transmit the same signal at a synchronized timing; and
A process of controlling the transmission power of the access point based on the determined transmission power, and controlling the grouped access points to transmit the same signal at a synchronized timing ;
Communication control method to do . In a communication control system including a plurality of access points that can communicate with a terminal wirelessly and a network control unit capable of communicating with the plurality of access points,
The plurality of access points or the network control unit,
Processing for acquiring an interference amount resulting from wireless communication between the terminal and the access point;
With reference to the acquired interference amount, access points whose mutual interference amount is equal to or greater than a threshold value are grouped to recalculate the interference amount when regarded as one access point, and among the grouped access points If the amount of interference that the recalculation is connected the terminal to the maximum access points, grouped the access point index value indicating the reception intensity becomes maximum with respect to the desired terminal, the other terminal Processing for determining the amplitude and phase of the transmission signal so that the received power is minimized,
A process for assisting the grouped access points to transmit the same signal at a synchronized timing; and
Controlling the access point based on the determined amplitude and phase ;
Communication control method to do . The plurality of access points or the network control unit,
Resetting the threshold so that the number of terminals accommodated in the grouped access points or the rate of accommodation satisfies a setting condition, and grouping the access points,
The communication control method according to claim 4 or 5.

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