JP2019041339A - Radio communication system, radio communication method, radio base station, and control station - Google Patents

Abstract

To improve the frequency utilization efficiency or total throughput or user QoS/QoE of an entire radio communication system in a dense environment of wireless LANs.SOLUTION: A radio base station comprises scenario information notification means which selects, based upon environment information that belonging radio terminals and the station itself can gather, proper scenario information indicative of current operation states of the station itself and belonging radio terminals out of a plurality of predefined prescribed scenarios, and notifies a control station of the proper scenario information. The control station selects, based upon scenario information of a plurality of radio base stations, proper policy information out of prescribed policies indicative of setting principles of parameters used for communication control over the respective base stations, and notifies the respective radio base stations of the setting principles. A radio base station comprises parameter setting means which sets, based upon the environment information, scenario information, and policy information, parameters for improving a radio environment as parameters used for communication control over the station itself and the radio terminals belonging to the station itself.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wireless communication system, a wireless communication method, a wireless base station, and a control station that improve a decrease in throughput in a dense environment of a wireless LAN (Local Area Network) by control according to the wireless environment of each wireless station. .

  In recent years, with the spread of portable and high-performance wireless terminals such as laptop computers and smartphones, wireless LANs based on the IEEE 802.11 standard have been widely used not only in businesses and public spaces, but also in general homes. The IEEE802.11 standard wireless LAN includes an IEEE802.11b / g / n standard wireless LAN using the 2.4 GHz band and an IEEE802.11a / n / ac standard wireless LAN using the 5 GHz band.

  In the wireless LAN of IEEE802.11b standard or IEEE802.11g standard, 13 channels are prepared at intervals of 5 MHz between 2400 MHz and 2483.5 MHz. However, when a plurality of channels are used at the same location, if the channels are used so that the spectra do not overlap in order to avoid interference, a maximum of 3 channels, and in some cases, 4 channels can be used simultaneously.

  In the wireless LAN of IEEE802.11a standard, in Japan, a total of 19 channels of 8 channels and 11 channels that do not overlap each other are defined between 5170 MHz and 5330 MHz and between 5490 MHz and 5710 MHz. In the IEEE802.11a standard, the bandwidth per channel is fixed at 20 MHz.

  The maximum transmission speed of the wireless LAN is 11 Mbps for the IEEE802.11b standard, and 54 Mbps for the IEEE802.11a standard or the IEEE802.11g standard. However, the transmission rate here is the transmission rate on the physical layer. Actually, since the transmission efficiency in the MAC (Medium Access Control) layer is about 50 to 70%, the upper limit of the actual throughput is about 5 Mbps in the IEEE802.11b standard, and 30 Mbps in the IEEE802.11a standard and the IEEE802.11g standard. Degree. In addition, the transmission rate further decreases as the number of communication stations that attempt to transmit information increases.

  On the other hand, in wired LANs, the introduction of Ethernet (registered trademark) 100Base-T interface and the spread of FTTH (Fiber to the home) using optical fiber in each home has led to the provision of high-speed lines of 100 Mbps to 1 Gbps. It is widespread, and further increase in transmission speed is required even in wireless LAN.

  Therefore, in the IEEE802.11n standard, which was standardized in 2009, the channel bandwidth, which had been fixed at 20 MHz, has been expanded to a maximum of 40 MHz, and the multiple input multiple output (MIMO) technology The introduction was decided. When transmission / reception is performed by applying all functions defined in the IEEE802.11n standard, a maximum communication speed of 600 Mbps can be realized in the physical layer.

  Furthermore, in the IEEE802.11ac standard, which was standardized in 2013, the channel bandwidth was expanded to 80 MHz or up to 160 MHz, and multi-user MIMO (MU) using Space Division Multiple Access (SDMA) was applied. -MIMO) The introduction of transmission methods has been decided. When transmission / reception is performed by applying all functions defined in the IEEE802.11ac standard, a maximum communication speed of about 6.9 Gbps can be realized in the physical layer.

  However, when the channel bandwidth is widened to 40 MHz, 80 MHz, 160 MHz, or 80 MHz + 80 MHz in the IEEE802.11ac standard, the number of channels that can be used simultaneously in the same place in the 5 GHz band is 19 channels with a channel bandwidth of 20 MHz. There are fewer 4 channels and 2 channels. That is, as the channel bandwidth increases, the number of usable channels decreases.

  In this way, the number of channels that can be used simultaneously in the same place is three for a 2.4 GHz band wireless LAN, two, four, nine, or nineteen channels for a 5 GHz band wireless LAN, depending on the channel bandwidth used for communication. Therefore, when actually introducing a wireless LAN, it is necessary to select a channel used by the wireless base station (access point: AP) in its own cell (BSS: Basic Service Set).

  Here, in a dense environment of a wireless LAN where the number of BSSs is larger than the number of usable channels, a plurality of BSSs use the same channel (OBSS: Overlapping BSS). In this case, the throughput of the BSS and the entire system is reduced due to the influence of interference between BSSs using the same channel. Therefore, in the wireless LAN, autonomous distributed access control that uses CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) to transmit data only when a channel is free due to carrier sense is used.

  Specifically, a communication station that has generated a transmission request first performs carrier sense for a predetermined sensing period (DIFS: Distributed Inter-Frame Space) to monitor the state of the wireless medium, and during this time, transmission by other communication stations is performed. If no signal is present, a random backoff is performed. The communication station continues to perform carrier sense even during the random back-off period, and obtains the right to use the channel when there is no transmission signal from another communication station during this period. A communication station that has acquired the right to use the channel can transmit data to other communication stations in the same BSS and receive data from those communication stations. When such CSMA / CA control is performed, in a dense environment of a wireless LAN using the same channel, the frequency of the channel becoming busy due to carrier sense increases, so the transmission opportunity (opportunity to obtain channel usage rights) decreases. As a result, the throughput decreases. Therefore, it is important to monitor the surrounding environment and select an appropriate channel.

  The channel selection method in the radio base station is not determined by the IEEE802.11 standard, so each vendor adopts its own method, but the most common channel selection method is the channel with the least interference power. There is a method for selecting the items in an autonomous and distributed manner. The radio base station performs carrier sensing for all channels for a certain period, selects a channel with the smallest interference power, and transmits / receives data to / from a terminal device under the selected channel. The interference power is a level of a signal received from a neighboring BSS or another system, and can be measured by, for example, a received signal strength indicator (RSSI).

  Here, a CCA (Clear Channel Assessment) threshold value for determining the channel usage status using the received signal strength (RSSI) is set when performing carrier sense in the radio base station. For example, in the IEEE802.11 standard, two CCA thresholds are defined. One is a CCA-SD (Signal Detection) threshold used when a preamble of a radio frame received by carrier sense can be detected, and the other is a wireless LAN signal in a received signal received by carrier sense. This is a CCA-ED (Energy Detection) threshold used when no preamble has been detected. In the IEEE802.11a standard, the CCA-SD threshold is set to -82 dBm, and the CCA-ED threshold is set to -62 dBm.

  When the RSSI is equal to or greater than the CCA-SD threshold and the preamble of the wireless LAN signal is detected by carrier sense, the channel is determined to be busy (communication impossible). Even if the preamble of the wireless LAN signal cannot be detected by carrier sense, if the RSSI is equal to or greater than the CCA-ED threshold, it is determined that the channel is busy (communication impossible) by considering it as an interference wave from a neighboring BSS or another system. . In other cases, it is determined that the channel is idle (communication is possible).

  As described above, in the wireless LAN of the IEEE802.11 standard, when a wireless base station (AP) forms a BSS, a channel that can be operated by the own BSS is determined. It is necessary to determine how much transmission power is used to transmit a radio signal.

  Then, the AP describes in a beacon frame that periodically transmits a set value of a parameter used in the own BSS and other parameters that can be supported by the own BSS, a probe response frame for a probe request frame received from a wireless terminal, and the like. The BSS is operated by transmitting a frame on the channel on which the operation is determined and notifying the wireless terminal to which the operation belongs and other wireless stations in the vicinity.

  In the wireless LAN, since such control is performed, the throughput decreases as the number of adjacent BSSs increases. Therefore, it is necessary to monitor the surrounding radio environment and set various parameters such as an appropriate channel, transmission power value, and CCA threshold.

  Here, in addition to the CCA threshold value used for CSMA / CA carrier sense, the setting value of the parameter used in the own BSS includes a transmission power value, an RS (Receiving Sensitively) threshold value that determines reception sensitivity, and a CW (Contention Window) value. Parameter values relating to access right acquisition such as minimum and maximum values and parameter values such as QoS (Quality of Services) are included. In addition, other parameters that can be supported by the AP include the bandwidth used for frame transmission, the basic data rate used for control frame transmission, and the data rate set (MCS: Modulation and coding scheme) related to the data rate at which data can be transmitted and received. Is included. Further, it is conceivable to change the size and shape of the communication area by dynamically changing the antenna directivity pattern by analog / digital beam forming or antenna switching.

  Furthermore, since the wireless LAN operates in CSMA / CA as described above, in an environment where BSSs are densely arranged, the frequency of the channel becoming busy due to interference in carrier sense increases. The opportunity to obtain the right to use) will decline. Therefore, it has been proposed to control the BSS communication area by controlling parameters such as antenna directivity pattern, transmission power value, CCA threshold value, RS threshold value, and improve throughput by increasing transmission opportunities (for example, Non-patent documents 1, 2).

  As a method for selecting and setting various parameters such as a use channel and transmission power value in the AP, for example, (a) a method using the default parameter value set by the AP manufacturer as it is, and (b) a user operating the AP. (C) A method for autonomously selecting and setting a parameter value based on wireless environment information detected by each AP at start-up, (d) A wireless LAN controller, etc. For example, a method of setting using parameter values determined by the centralized control device can be given.

J. Zhu (Intel), et al., “Adaptive CSMA for scalable network capacity in high-density WLAN: a hardware prototyping approach,” in Proc. IEEE INFOCOM, 2006. H. Ma, et al., “On loss differentiation for CSMA-based dense wireless network,” IEEE Commun. Lett., Vol.11, no.11, pp.877-879, Nov. 2007.

  Among the methods (a) to (d) for selecting and setting the frequency channel, bandwidth, and other parameters described above, in particular, an inexpensive AP often uses default parameters set by the manufacturer as they are. . However, in an environment where a plurality of APs of the same manufacturer are installed nearby, all APs use the same frequency channel and transmission power value, so interference occurs between APs and communication quality deteriorates. There is a problem to do.

  In a relatively small network such as a general home, it is conceivable that a user operating a wireless LAN sets appropriate parameters. In particular, various parameters can be set in an environment where there is no external interference source. However, in environments where wireless LAN is used in urban areas, apartment buildings, etc., or in medium or large networks, each wireless LAN is appropriate. It is difficult for a user or an administrator to set a simple parameter setting.

  In an AP capable of autonomous distributed operation in which each AP autonomously selects a parameter value based on wireless environment information detected at its own station at the time of activation, an appropriate parameter value varies depending on the order in which the AP is activated. In addition, each AP can select and set appropriate parameter values in its own station, so it can be optimized locally. However, the entire system cannot be optimized. It becomes difficult.

  For example, even if such a change in the wireless environment occurs, such as a change in the number of APs being activated, a change in the wireless terminal devices under each AP, a change in the amount of data transmitted by the wireless devices in each cell, the channel used In addition, since the bandwidth is not optimized, there is a problem that a difference occurs between the throughputs of the respective cells or the throughput of the entire system deteriorates.

  For this reason, for example, in the case of a small to large-scale wireless LAN system formed by several tens to several hundreds of APs such as a university, office, stadium, and station environment, a dedicated device called a “wireless LAN controller” is used. There is a method of controlling the AP by arranging it, determining the parameter value of each AP by the wireless LAN controller, and reflecting it on the AP.

  In order to perform appropriate parameter setting by the wireless LAN controller, environment information regarding the wireless environment and traffic status is collected from the control target AP, the wireless terminal belonging to them, the user terminal using a different frequency such as a license band, and the like. It is necessary to calculate appropriate parameters after processing environmental information. However, since the number of unlicensed band APs including wireless LAN routers that are temporarily installed and the number of terminals that use them have increased explosively, the amount of environmental information collected has become enormous, and the optimal parameters are repeated. There was a problem that took a long time to calculate. Furthermore, it is difficult to flexibly cope with cases where the optimization index is different.

  The present invention performs AP parameter setting so as to improve the frequency utilization efficiency or overall throughput or user QoS / QoE of the entire wireless communication system in a dense environment of a wireless LAN, and reduces local throughput or QoS / It is an object of the present invention to provide a radio communication system, a radio communication method, a radio base station, and a control station that can avoid QoE degradation.

  The first invention is based on CSMA / CA access control, a plurality of radio base stations that perform radio communication with their respective radio terminals, and a plurality of radio base stations connected to the radio environment information and operation of the plurality of radio base stations. In a wireless communication system comprising a control station for notifying information necessary for determining parameters used for communication control of each wireless base station and wireless terminal based on environmental information including medium setting information and accommodated traffic information, Based on the environmental information that can be collected by the base station and its own radio terminal, the base station can select appropriate scenario information that indicates the current operating status of the base station and the radio terminal from among a plurality of predefined scenarios. Scenario information notifying means for selecting and notifying the control station, the control station based on the scenario information of a plurality of radio base stations, the parameters used for communication control of each radio base station. Policy information notification means is provided for selecting appropriate policy information from a prescribed policy indicating a meter setting policy and notifying each radio base station, and the radio base station communicates with the own station and the radio terminal belonging to the own station. As parameters used for control, parameter setting means for setting parameters for improving the wireless environment based on environment information, scenario information, and policy information notified from the control station is provided.

  In the wireless communication system of the first invention, the scenario information notification means of the wireless base station includes, as environment information, the number of belonging terminals, the number of peripheral management APs, the number of peripheral management APs, the traffic amount for each channel, the uplink traffic ratio, the interference amount Predefined based on (SINR), transmission packet length, packet retransmission rate, up / down throughput, capability information of own station and belonging terminal station, operation information of own station and belonging terminal station, and all or part of radar detection information In this configuration, the environmental similarity with each of the plurality of prescribed scenarios is calculated, and appropriate scenario information indicating the current operation state of the own station is selected.

  In the wireless communication system of the first invention, the policy information notification means of the control station selects a parameter to be operated by the wireless base station or a parameter to be operated corresponding to the scenario information notified from the scenario information notification means The policy information corresponding to the conditions to be considered is selected.

  In the wireless communication system of the first invention, the scenario information notifying means of the wireless base station is a means for updating a predefined defined scenario or creating a new defined scenario based on environmental information, scenario information and policy information. including.

  In the wireless communication system of the first invention, the policy information notifying means of the control station includes means for updating a specified policy or creating a new specified policy based on scenario information notified from a plurality of wireless base stations. .

  In the wireless communication system according to the first aspect of the invention, scenario information output from a plurality of wireless base stations is aggregated between the wireless base station and the control station and notified to the control station, and policy information notified from the control station Intermediate control stations that reconfigure and notify each radio base station may be hierarchically provided.

  A second invention is a control station connected to a plurality of radio base stations that perform radio communication with a radio terminal to which each belongs by CSMA / CA access control, and includes radio environment information and operational setting information of the plurality of radio base stations. In the wireless communication method for notifying information necessary for determining parameters used for communication control of each wireless base station and wireless terminal based on environment information including accommodation traffic information, the wireless base station includes: Based on the environmental information that can be collected by the local station, select the appropriate scenario information indicating the current operating status of the local station and the wireless terminal to which it belongs from a number of predefined scenarios, and notify the control station A scenario information notification step, and the control station is a rule indicating a policy for setting parameters used for communication control of each radio base station based on scenario information of a plurality of radio base stations. It has a policy information notification step of selecting appropriate policy information from the policy and notifying each radio base station, and the radio base station is used as a parameter used for communication control of the own station and the radio terminal belonging to the own station. There is a parameter setting step for setting parameters for improving the wireless environment based on the environment information, the scenario information, and the policy information notified from the control station.

  According to a third aspect of the present invention, a plurality of radio base stations that perform radio communication with a radio terminal to which each belongs, and a plurality of radio base stations, and radio environment information and operation of the plurality of radio base stations, by CSMA / CA access control. A radio base station of a radio communication system comprising a control station for notifying information necessary for determining parameters used for communication control of each radio base station and radio terminal based on environmental information including medium setting information and accommodated traffic information Based on the environment information that can be collected at the station and the wireless terminal to which the station belongs, appropriate scenario information indicating the current operational status of the station and the wireless terminal to which the station belongs is selected from a plurality of predefined scenarios. Based on scenario information notification means for selecting and notifying the control station, environment information, and scenario information of multiple radio base stations from the control station, it is used for communication control of each radio base station. That based on the policy information notified by selecting from among the specified policy that indicates the parameter setting policies, and a parameter setting means for setting the parameters to improve the radio environment.

  According to a fourth aspect of the present invention, wireless environment information and operation of a plurality of wireless base stations connected to a plurality of wireless base stations and a plurality of wireless base stations that perform wireless communication with wireless terminals to which the wireless terminal belongs are controlled by CSMA / CA access control. A control station of a radio communication system comprising a control station for notifying information necessary for determining parameters used for communication control of each radio base station and radio terminal based on environment information including medium setting information and accommodated traffic information In this case, scenario information indicating the current operation state of the local station and the associated wireless terminal is notified based on the wireless terminal belonging to the wireless base station and the environmental information that can be collected by the own station. Policy information that selects appropriate policy information from the specified policies that indicate the policy for setting parameters used for base station communication control, and notifies each radio base station Including intellectual means.

  According to the present invention, in a dense environment of a wireless LAN in which access control is performed by CSMA / CA, the environment information is converted into “scenario information” in each radio base station, and the control station converts each radio based on the “scenario information”. “Policy information” indicating a parameter setting policy used for communication control of the base station is generated and notified to each radio base station. Each AP sets the appropriate parameters based on the policy information and the environmental information collected by itself, thereby optimizing the entire wireless communication system using the centralized control method and calculating the parameters using the autonomous distributed control method. Real-time characteristics can be achieved. As a result, the frequency of channel access by CSMA / CA is improved, and each radio base station can improve the throughput while increasing the communication opportunity. Therefore, user QoS / QoE can be improved.

It is a figure which shows the structural example of the radio | wireless communications system of this invention. It is a figure which shows the flow of information in the radio | wireless communications system of this invention, and a specific example. It is a figure which shows the example of a parameter setting according to policy information. It is a figure which shows the structural example of AP and a control station.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration example of a wireless communication system of the present invention.
In FIG. 1, wireless base stations (AP) 1 and 2 perform wireless communication with wireless terminals (STAs) to which they belong on the shared wireless frequency band of the wireless LAN. AP1 performs wireless communication with the associated STA11 and STA12, and AP2 performs wireless communication with the associated STA21 and STA / UE22. Here, the STA / UE 22 has a function of communicating via another line such as a cellular line. The APs 1 and 2 are connected to the control station 5 via a network such as a wired line or a cellular line. There are many APs connected to the control station 5, and intermediate control stations may be arranged hierarchically between the AP and the control station 5.

  Further, a higher-level control station 6 or an external database 7 may be connected to the control station 5. The external database 7 stores information other than communication such as monitoring camera information, weather forecast information, and event holding information. The control station 5 may exchange information with the host control station 6 or the external database 7 and use it together with scenario information from the APs 1 and 2 when determining policy information to be described later.

  The interference range / carrier detection range 10 of AP1 includes AP2, STA21, and STA / UE22 in addition to the belonging STA11 and STA12. The AP2 interference range / carrier detection range 20 includes unmanaged APs in addition to the belonging STA21 and STA / UE22. Therefore, the wireless environments of AP1 and AP2 are different, and the environment information collected by each is different.

  For this reason, the centralized control method for individually calculating appropriate parameters used for communication control of each AP based on the environment information of each AP in the control station 5 is collected, although the entire wireless communication system can be optimized. Since the amount of information is enormous, the processing time is long and real-time control is difficult. On the other hand, the autonomous distributed control method in which each AP distributes and controls parameters according to the environment information of the own station can calculate parameters in the own station in real time, but it is difficult to optimize the entire wireless communication system. The present invention takes advantage of both types of features and converts the environment information into “scenario information” in which each AP is aggregated, and the control station 5 sets parameters used for communication control of each AP based on this “scenario information”. “Policy information” indicating the policy is generated and notified to each AP. Each AP sets the appropriate parameters based on the policy information and the environmental information collected by itself, thereby optimizing the entire wireless communication system using the centralized control method and calculating the parameters using the autonomous distributed control method. Real-time characteristics can be achieved.

FIG. 2 shows a flow of information and a specific example in the wireless communication system of the present invention.
In FIG. 2, the STA measures the environmental information around the own station according to an instruction from the belonging AP or the control station or voluntarily, and notifies the collected AP of the collected environmental information.

  The AP (1) measures the environmental information of its own station, (2) collects environmental information notified from the STA to which it belongs, and (3) stores the environmental information in its own station based on the environmental information of the STA and the STA to which it belongs. The degree of environmental similarity with each of a plurality of predefined scenarios is calculated, and appropriate scenario information indicating the current operation state of the own station is selected and notified to the control station. Here, the environmental information includes, for example, the number of belonging terminals, the number of peripheral management APs, the number of non-peripheral management APs, the traffic amount for each channel, the uplink traffic ratio, the interference amount (SINR), the transmission packet length, the packet retransmission rate, the upper and lower throughputs. , Capability information of own station and belonging terminal station, operation information of own station and belonging terminal station, radar detection information, and the like.

The scenario information is information that is aggregated based on the relationship between each parameter set in the AP and STA and the effect on the environment information, and is information that enables selection of policy information in the control station. For example, the antenna attenuator (ATT) control effect, the channel allocation effect, the bandwidth control effect, the attribution change effect, the RTS / CTS application effect, and the like are expressed as “Yes / No” or “Large / Medium / Small”. For example, the scenario information for the environmental information of AP1 and the belonging STAs 11 and 12 is as follows.
ATT control effect: No Channel allocation effect: Yes Bandwidth control effect: Yes Attribution change effect: No

The scenario information for the environmental information of AP2 and the STA21 and STA / UE22 to which it belongs is as follows.
ATT control effect: None Channel allocation effect: None Bandwidth control effect: Available Attribution change effect: None

  The scenario information may be notified to the control station by further collecting scenario information from a plurality of APs at the intermediate control station. The scenario information may include a part of the environment information.

  The control station (1) collects scenario information from multiple APs, and (2) corresponds to the parameters that the AP should operate in response to the acquired scenario information, or the conditions that should be considered in selecting the parameters to operate Appropriate policy information is selected from the prescribed policies and notified to the AP.

The policy information is a parameter setting policy used for communication control of each AP with respect to the scenario information as described above, and includes the following, for example.
(a) Fixed parameters that uniquely determine and notify parameters • Channel = 36
・ ATT = 10dB
(b) Range specification parameter that specifies only the value range • Channel = 36 to 40
・ ATT = 10dB or more

(c) Conditional parameters used under specified conditions • Traffic volume is less than 20 Mbps: channel = 36
・ Traffic volume is 20Mbps or more: Channel = 40
・ The number of peripheral management APs is less than 30: ATT = 10 dB or more ・ The number of peripheral management APs is 30 or more: ATT = 20 dB or more
(d) Parameters used for each service-General user SSID: ATT = 10 dB
・ Press member SSID: ATT = 0dB

  The AP (1) collects policy information from the control station. (2) Based on the collected policy information, scenario information in the own station, and each environment information of the own station and the belonging STA, the AP and the belonging STA. The parameters used for the communication control are generated, set in the own station, and notified to the STA to which it belongs.

  Furthermore, the AP selects scenario information corresponding to the environment information from the predefined scenarios defined in its own station, and defines the defined scenario based on the collected environmental information and policy information notified from the control station. It may be updated or newly established. Further, the control station 5 selects the policy information of each AP from the prescribed policy in consideration of the scenario information from a plurality of APs. However, the prescribed policy may be updated or newly established based on the collected scenario information.

  Further, the policy information may be an autonomous distributed control procedure in each AP as shown below, or a value passed to the autonomous distributed control of each AP.

FIG. 3 shows an example of parameter selection according to the policy information.
In FIG. 3, (1) is an example showing a procedure of autonomous distributed control in each AP as policy information. The AP 1 grasps the traffic amount: 15 Mbps as environment information, and notifies the control station 5 of “channel allocation effect” and the like as scenario information including other environment information. Based on this scenario information, the control station 5 notifies AP1 of “traffic volume and channel correspondence table” which is a procedure of autonomous distributed control as policy information. Since the traffic volume of the AP 1 is 15 Mbps, the AP 1 sets the local station to communicate via the channel 36 according to this “traffic volume and channel correspondence table” and notifies the STA to which it belongs.

  (2) is an example showing values passed to autonomous distributed control of each AP as policy information. AP2 grasps the traffic volume: 25 Mbps as environmental information, has an “area congestion level and channel correspondence table” as an autonomous decentralized control procedure, and includes “channel allocation effect” and “ The control station 5 is notified of the traffic volume for each channel. Based on this scenario information, the control station 5 notifies AP2 of “area congestion level: 2” as policy information. The AP 2 sets the local station to communicate with the channel 40 corresponding to the “area congestion level: 2” according to the “area congestion level and channel correspondence table” of the local station, and notifies the STA to which it belongs.

FIG. 4 shows a configuration example of the AP and the control station.
FIG. 4 (1) shows a configuration example of the AP. The communication unit 101 communicates with the control station via the belonging STA and the network. The environmental information collection unit 102 collects environmental information measured by the local station. The environment information holding unit 103 holds environment information notified from the belonging STA. The scenario information determination unit 104 selects appropriate scenario information indicating the current operation state of the local station from the predefined scenarios defined in the local station based on the environment information of the local station and the STA to which it belongs, and performs communication. Notification is made to the control station via the unit 101. The prescribed scenario update unit 105 updates or newly establishes the definition of the prescribed scenario based on the collected environment information and policy information notified from the control station. The policy information holding unit 106 holds policy information notified from the control station. The parameter setting unit 107 generates parameters used for communication control of the local station and the belonging STA based on the policy information notified from the control station, the scenario information in the own station, and the environment information of the own station and the belonging STA. Then, the STA is set to its own station and notified to the STA to which it belongs. The control unit 108 controls the overall operation of the AP.

  FIG. 4 (2) shows a configuration example of the control station. The communication unit 501 communicates with the AP via a network. The scenario information holding unit 502 holds scenario information notified from the AP. Based on the acquired scenario information, the policy information generation unit 503 selects appropriate policy information from the prescribed policy indicating the parameter setting policy used for communication control of each AP, and notifies the AP. The prescribed policy update unit 504 updates or newly establishes the prescribed policy based on the collected scenario information. The control unit 505 controls the operation of the entire control station.

1, 2 Radio base station (AP)
4 Network 5 Control Station 6 Higher Control Station 7 External Database 10 AP1 Interference Range / Carrier Detection Range 11, 12 Wireless Terminal (STA)
20 AP2 interference range / carrier detection range 21 Wireless terminal (STA)
22 Wireless terminal (STA / UE)

Claims (9)

With CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) access control, a plurality of wireless base stations that perform wireless communication with the wireless terminals to which they belong,
Based on the environment information including the wireless environment information, operational setting information, and accommodated traffic information of the plurality of wireless base stations connected to the plurality of wireless base stations, communication control of each wireless base station and the wireless terminal is performed. A wireless communication system including a control station that notifies information necessary for determining a parameter to be used,
The radio base station indicates a current operation state of the own station and the belonging radio terminal from a plurality of predefined rules based on the environment information that can be collected by the assigned radio terminal and the own station. A scenario information notification means for selecting appropriate scenario information and notifying the control station;
The control station selects appropriate policy information from a prescribed policy indicating a parameter setting policy used for communication control of each radio base station based on the scenario information of the plurality of radio base stations, and each radio base station Policy information notification means to notify
The radio base station improves the radio environment based on the environment information, the scenario information, and the policy information notified from the control station as the parameters used for communication control of the own station and a radio terminal belonging to the own station. A wireless communication system, comprising: parameter setting means for setting a parameter for performing the operation. The wireless communication system according to claim 1, wherein
The scenario information notification means of the radio base station includes, as the environment information, the number of belonging terminals, the number of peripheral management APs, the number of APs not managed by peripheral management, the traffic amount for each channel, the uplink traffic ratio, the interference amount (SINR), the transmission packet length Multiple predefined scenarios based on all or part of packet retransmission rate, up / down throughput, capability information of own station and belonging terminal station, operation information of own station and belonging terminal station, radar detection information A wireless communication system, wherein the scenario similarity is calculated and the appropriate scenario information indicating the current operation state of the local station is selected. The wireless communication system according to claim 1, wherein
The policy information notification means of the control station is a parameter to be operated by the radio base station corresponding to the scenario information notified from the scenario information notification means, or a condition to be considered in selecting a parameter to be operated A wireless communication system, characterized in that the policy information corresponding to is selected. The wireless communication system according to claim 1, wherein
The scenario information notifying means of the radio base station includes means for updating a predefined rule scenario or creating a new rule scenario based on the environment information, the scenario information, and the policy information. A wireless communication system. The wireless communication system according to claim 1, wherein
The policy information notifying means of the control station includes means for updating the specified policy or creating a new specified policy based on the scenario information notified from the plurality of radio base stations. Wireless communication system. The wireless communication system according to claim 1, wherein
The scenario information output from a plurality of radio base stations is aggregated between the radio base station and the control station and notified to the control station, and the policy information notified from the control station is reconfigured. A wireless communication system characterized in that intermediate control stations that notify each wireless base station are hierarchically provided. CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) access control, which is a control station connected to a plurality of radio base stations that perform radio communication with a radio terminal to which each belongs, Radio environment information of the plurality of radio base stations, In a wireless communication method for notifying information necessary for determining parameters used for communication control of each wireless base station and the wireless terminal based on environment information including operational setting information and accommodated traffic information,
The radio base station indicates a current operation state of the own station and the belonging radio terminal from a plurality of predefined rules based on the environment information that can be collected by the assigned radio terminal and the own station. A scenario information notification step of selecting appropriate scenario information and notifying the control station;
The control station selects appropriate policy information from a prescribed policy indicating a parameter setting policy used for communication control of each radio base station based on the scenario information of the plurality of radio base stations, and each radio base station A policy information notification step for notifying
The radio base station improves the radio environment based on the environment information, the scenario information, and the policy information notified from the control station as the parameters used for communication control of the own station and a radio terminal belonging to the own station. A wireless communication method comprising: a parameter setting step for setting a parameter to be performed. With CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) access control, a plurality of wireless base stations that perform wireless communication with the wireless terminals to which they belong,
Based on the environment information including the wireless environment information, operational setting information, and accommodated traffic information of the plurality of wireless base stations connected to the plurality of wireless base stations, communication control of each wireless base station and the wireless terminal is performed. In a radio base station of a radio communication system comprising a control station that notifies information necessary for determining parameters to be used,
Based on the environmental information that can be collected by the wireless terminal to which it belongs and its own station, select appropriate scenario information indicating the current operating status of the wireless station and the wireless terminal to which it belongs from a plurality of predefined scenarios. Scenario information notifying means for notifying the control station;
Based on the environment information and the scenario information of the plurality of radio base stations from the control station, the policy information selected and notified from the regulation policy indicating the parameter setting policy used for communication control of each radio base station Parameter setting means for setting parameters for improving the wireless environment based on
A wireless base station of a wireless communication system, comprising: With CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) access control, a plurality of wireless base stations that perform wireless communication with the wireless terminals to which they belong,
Based on the environment information including the wireless environment information, operational setting information, and accommodated traffic information of the plurality of wireless base stations connected to the plurality of wireless base stations, communication control of each wireless base station and the wireless terminal is performed. A control station of a wireless communication system comprising a control station for notifying information necessary for determining a parameter to be used,
Based on the environmental information that can be collected by the wireless base station and the local station from the wireless base station, the scenario information indicating the current operation state of the local station and the wireless terminal to which it belongs is notified, and based on the scenario information, A radio communication system comprising policy information notification means for selecting appropriate policy information from a prescribed policy indicating a parameter setting policy used for communication control of a radio base station and notifying each radio base station Control station.

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