JP4821332B2 - Wireless LAN system and access point - Google Patents

Description

  The present invention relates to a wireless LAN terminal that performs wireless communication based on a wireless LAN standard, an access point, and a wireless LAN system including these.

  Wireless LAN systems based on standards such as IEEE 802.11a and IEEE 802.11b are known. In such a wireless LAN system, there is a method in which each wireless LAN terminal communicates with each other via a relay station called an access point. In such a system, when the number of wireless LAN terminals that communicate via one access point increases, the communication load generated at the access point by these wireless LAN terminals increases.

  When the communication load of the access point exceeds a value that allows normal communication, a loss of communication data or the like occurs. In such a situation, in the case of communication such as voice communication such as VoIP (Voice over Internet Protocol) or communication that requires a relatively real time property such as streaming distribution of video or the like, retransmission of missing communication data is not performed. Sound and video are interrupted, which is a problem.

  In order to avoid this, for example, Patent Document 1 discloses a technique for distributing the attribution of a terminal device to an appropriate access point according to the load status of each access point. When the wireless LAN terminal belongs to an access point, the wireless system described in the patent document permits the terminal device to belong to the access point if the load on the access point is lighter than a predetermined value. The wireless LAN terminal to which the wireless LAN terminal intends to belong is reported, and the wireless LAN terminal is instructed to belong to a relatively light load among the other access points included in the report.

JP 2004-221684 A

  By the way, in a wireless LAN system, a wireless LAN terminal can be connected to a network by belonging to the nearest access point. However, only being connected to the network generates a small amount of traffic, and the communication load on the access point to which the wireless LAN terminal belongs is only caused by control data or the like.

  Here, the wireless system described in Patent Literature 1 may change the access point to which it belongs, depending on the communication load status of the access point at the time of belonging, regardless of whether or not data communication is performed. is there. Usually, a wireless LAN terminal often attempts to belong to an access point with the best received signal quality. For this reason, when the access point to be attributed is changed, the wireless LAN terminal is attributed to an access point having relatively poor received signal quality, even if it is only attributed.

  Generally, the communication load of an access point changes from moment to moment depending on the communication status of other wireless LAN terminals belonging to the access point. For this reason, with the technique described in Patent Document 1, the wireless LAN terminal will be assigned to an access point with relatively poor received signal quality after that because the communication load of the access point exceeds a predetermined value at the time of belonging. .

  In particular, when the wireless LAN terminal is a telephone terminal, only a few wireless LAN terminals belonging to one access point actually perform communication, and most of them wait for an incoming call only by belonging. There are many usages. In such a usage, when other wireless LAN terminals are communicating, at the time of belonging, if the belonging is changed to a distant access point, the wireless LAN terminal will be in a state of poor received signal quality thereafter. As a result, outgoing or incoming calls are made, and the call quality may not be kept high.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to maintain a high communication quality and to allow many wireless LAN terminals to belong to one access point. It is in.

  In order to solve the above-described problem, the access point according to the present invention permits the wireless LAN terminal to belong to the wireless LAN terminal regardless of the current communication load of the wireless LAN terminal and belongs to the wireless LAN terminal. When a wireless LAN terminal starts data communication, prior to the start of data communication of the wireless LAN terminal, whether to allow data communication by the wireless LAN terminal is controlled according to its own communication load.

For example, a first aspect of the present invention is a wireless LAN system including a plurality of access points and a plurality of wireless LAN terminals,
Each of the plurality of wireless LAN terminals is
A terminal side attribution processing means that performs attribution processing with the nearest access point,
Prior to data communication via the belonging access point, a communication request transmitting means for transmitting to the access point a communication request for inquiring whether data communication via the access point is possible,
In response to the communication request, when a communication permission for permitting data communication via the access point is acquired from the access point, data communication means for performing data communication via the access point by wireless communication ;
A primary or secondary request for an AP list in which the received signal quality from the access point is associated with the identification information of the access point receiving the radio wave of sufficient strength to belong is received from the belonging access point An AP list transmission means for searching for another access point to create the AP list, and transmitting the created AP list to the access point to which it belongs,
When an attribution change instruction including identification information of the belonging access point is received from the belonging access point, the terminal side attribution processing means is instructed to the identification information access point included in the attribution change instruction. After changing the attribution, the communication request transmission means is instructed to have the attribution change instruction means to transmit the communication request to the newly attributed access point , and
Each of the plurality of access points is
AP side attribution processing means for performing attribution processing with the wireless LAN terminal;
A communication load calculating means for calculating a communication load generated in the own access point by wireless communication of the wireless LAN terminal belonging to the own access point;
A communication load determination unit that determines whether or not the communication load calculated by the communication load calculation unit is less than a predetermined value when the communication request is received from a wireless LAN terminal belonging to the own access point;
When the communication load determining means determines that the communication load is less than a predetermined value, the communication permission is transmitted to the wireless LAN terminal that has transmitted the communication request, and the communication load is determined in advance. If it is determined that the value above, the communication availability transmitting means for transmitting a primary request for the AP list to the wireless LAN terminal having transmitted the communication request,
When the AP list is received from the wireless LAN terminal belonging to the own access point, a load status primary request for inquiring whether the communication load is less than the predetermined value is displayed in the AP list. Load status requesting means for transmitting to other access points corresponding to the included identification information;
A load including the determination result by causing the communication load determination means to determine whether or not the communication load is less than a predetermined value when receiving a primary or secondary request of the load status from another access point A load status notification means for transmitting a status notification;
When a load status notification including that the communication load is less than a predetermined value is received from another access point, another access with a communication load less than a predetermined value is referred to the AP list. An attribution change instruction transmitting means for transmitting an attribution change instruction including identification information of another access point associated with the highest received signal quality among the points to the wireless LAN terminal that has transmitted the AP list; /> I have a,
The communication availability transmitting means is
When the AP list transmitted from the wireless LAN terminal in response to the primary request for the AP list does not include the identification information of other access points, the other information being communicated through the own access point Send a secondary request for the AP list to the wireless LAN terminal,
The load status request means includes
When receiving the AP list from a wireless LAN terminal in response to the secondary request for the AP list, a secondary request for a load status for inquiring whether the communication load is less than the predetermined value, Send to other access points corresponding to the identification information included in the AP list,
Attribution change instruction transmission means
In response to a secondary request of the AP list, when a load status notification including that the communication load is less than a predetermined value is received from another access point in response to the secondary request of the load situation, With reference to the AP list received from the wireless LAN terminal, identification information of other access points associated with the highest received signal quality among other access points having a communication load less than a predetermined value is obtained. attribution change instruction containing, and transmits to the AP list wireless LAN terminal having transmitted, and instructs the communication availability transmitting unit, to transmit said communication permission to the wireless LAN terminal having transmitted the communication request Rukoto A wireless LAN system is provided.

A second aspect of the present invention is an access point that is used in a wireless LAN system and performs wireless communication with a wireless LAN terminal,
AP side attribution processing means for performing attribution processing with the wireless LAN terminal;
A communication load calculating means for calculating a communication load generated in the own access point by wireless communication of the wireless LAN terminal belonging to the own access point;
A communication load determining means for determining whether or not the communication load calculated by the communication load calculating means is less than a predetermined value when a communication request is received from a wireless LAN terminal belonging to the own access point;
When the communication load determining means determines that the communication load is less than a predetermined value, a communication permission is transmitted to the wireless LAN terminal that has transmitted the communication request, and the communication load is determined in advance. When it is determined that the value is equal to or greater than the value, the other access point is included in the identification information of the other access point that is receiving a radio wave having sufficient strength to belong to the wireless LAN terminal that has transmitted the communication request. a communication availability transmitting means for transmitting a primary request AP list that associates reception signal quality from,
When the AP list is received from the wireless LAN terminal belonging to the own access point, a load status primary request for inquiring whether the communication load is less than the predetermined value is displayed in the AP list. Load status requesting means for transmitting to other access points corresponding to the included identification information;
A load including the determination result by causing the communication load determination means to determine whether or not the communication load is less than a predetermined value when receiving a primary or secondary request of the load status from another access point A load status notification means for transmitting a status notification;
When a load status notification including that the communication load is less than a predetermined value is received from another access point, another access with a communication load less than a predetermined value is referred to the AP list. An attribution change instruction transmitting means for transmitting an attribution change instruction including identification information of another access point associated with the highest received signal quality among the points to the wireless LAN terminal that has transmitted the AP list; /> I have a,
The communication availability transmitting means is
When the AP list transmitted from the wireless LAN terminal in response to the primary request for the AP list does not include the identification information of other access points, the other information being communicated through the own access point Send a secondary request for the AP list to the wireless LAN terminal,
The load status request means includes
When receiving the AP list from a wireless LAN terminal in response to the secondary request for the AP list, a secondary request for a load status for inquiring whether the communication load is less than the predetermined value, Send to other access points corresponding to the identification information included in the AP list,
Attribution change instruction transmission means
In response to a secondary request of the AP list, when a load status notification including that the communication load is less than a predetermined value is received from another access point in response to the secondary request of the load situation, With reference to the AP list received from the wireless LAN terminal, identification information of other access points associated with the highest received signal quality among other access points having a communication load less than a predetermined value is obtained. attribution change instruction containing, and transmits to the AP list wireless LAN terminal having transmitted, and instructs the communication availability transmitting unit, to transmit said communication permission to the wireless LAN terminal having transmitted the communication request Rukoto Provide an access point characterized by

  According to the wireless LAN system of the present invention, the communication quality of the wireless LAN terminal can be kept high, and more wireless LAN terminals can be attributed to one access point.

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

  FIG. 1 shows an example of the configuration of a wireless LAN system 10 according to an embodiment of the present invention. The wireless LAN system 10 includes a plurality of wireless LAN terminals 20 and a plurality of access points 30. The communication area 13-1 indicates a range in which a radio wave having an assignable intensity is transmitted from the access point 30-1. The communication area 13-2 indicates a range in which a radio wave having an assignable intensity is transmitted from the access point 30-2. In FIG. 1, a dotted-line double arrow indicates that the wireless LAN terminal 20 is belonging, and a solid-line double arrow indicates that the wireless LAN terminal 20 is communicating.

  Each access point 30 is connected to the wired network 11, and performs wireless communication with each wireless LAN terminal 20 based on a wireless LAN standard such as IEEE802.11a or IEEE802.11b. Wired communication is performed with another communication device 12 connected to the wired network 11 via the communication standard such as Ethernet (registered trademark). In FIG. 1, the wired network 11 is applied as a network connecting a plurality of access points 30, but this may be a wireless network of a method different from the communication with the wireless LAN terminal 20.

  Each wireless LAN terminal 20 belongs to, for example, the access point 30 having the best received signal quality. The received signal quality is, for example, received electric field strength, SNR (Signal to Noise Ratio), BER (Bit Error Rate) or the like. Then, the wireless LAN terminal 20 performs wireless communication based on the wireless LAN with the access point 30 to which the wireless LAN terminal 20 belongs, and through the access point 30, another wireless LAN terminal 20 belonging to the access point 30 or other Communication is performed with other wireless LAN terminals 20 belonging to the access point 30, the communication device 12 connected to the wired network 11, and the like. In the present embodiment, each wireless LAN terminal 20 is a voice communication terminal that mainly handles voice data. As another example, the wireless LAN terminal 20 may be a data communication terminal that handles data other than voice data.

  By the way, when the number of wireless LAN terminals 20 that communicate via one access point 30 increases, the communication band allocated to each wireless LAN terminal 20 may decrease, and audio and video images that require real-time characteristics may be reduced. Transmission may be hindered. In order to avoid this, the access point 30 in the present embodiment starts the communication of each wireless LAN terminal 20 so that the communication load generated by the communication of the subordinate wireless LAN terminal 20 is less than a predetermined value. Allow or deny

  Here, the communication load is the data amount actually transmitted / received with respect to the data amount that can be transmitted / received per unit time. In the present embodiment, the wireless LAN terminal 20 has a voice communication function, and the wireless LAN terminal 20 is connected to the number of wireless LAN terminals 20 in communication with one wireless LAN terminal 20 as voice communication. The communication load is simply calculated by multiplying by the communication load calculated in advance. In this embodiment, each access point 30 restricts the number of subordinate wireless LAN terminals 20 that can communicate simultaneously to, for example, three or less, thereby generating communication caused by communication of the subordinate wireless LAN terminals 20. The load is set to be less than a predetermined value.

  In addition, each access point 30, such as the wireless LAN terminal 20-1 shown in FIG. 1, when newly assigning the wireless LAN terminal 20, other authentication or the like regardless of the current communication load. The attribution of the wireless LAN terminal 20 is permitted in consideration of the factors. In this case, the access point 30 stores in advance the maximum value of the number of wireless LAN terminals 20 to which the access point 30 can belong, and if it is less than the maximum value, the access point 30 considers other factors such as authentication and assigns the wireless LAN terminal 20 to the attribution. If it is permitted and the value exceeds the maximum value, the attribution of the new wireless LAN terminal 20 may not be permitted.

  Here, when the wireless LAN terminal 20-4, the wireless LAN terminal 20-5, and the wireless LAN terminal 20-7 are communicating via the access point 30-1, as shown in FIG. When the LAN terminal 20-6 starts communication, the wireless LAN terminal 20-6 transmits a communication request to the belonging access point 30-1. If there are less than three wireless LAN terminals 20 in communication, the access point 30-1 returns a communication permission in response to the communication request, and the wireless LAN terminal 20-6 passes through the access point 30-1. Start communication.

  However, in the example shown in FIG. 1, three wireless LAN terminals 20 are already communicating via the access point 30-1. Therefore, the access point 30-1 sends a primary request for an AP list, which is a list of identification information of other access points 30 receiving a sufficiently strong radio wave, to the wireless LAN terminal 20-6. Send. The wireless LAN terminal 20-6 performs channel search or the like to detect that a radio wave having sufficient strength to belong is received from the access point 30-2. Then, for example, the wireless LAN terminal 20-6 acquires the identification information of the access point 30-2 from the information included in the beacon, creates a primary response of the AP list including the acquired identification information, and creates the access point 30 -1.

  The access point 30-1 makes a load status request for inquiring whether or not the communication load is less than a predetermined value to the access point 30-2 corresponding to the identification information included in the primary response of the acquired AP list. And transmitted via the wired network 11. The access point 30-2 determines whether or not the current communication load is less than a predetermined value based on the current communication load, and sends a load status response including the result to the access point 30-1. Reply via the network 11. In the example shown in FIG. 1, the access point 30-2 has a communication load generated by the communication of one wireless LAN terminal 20, and there is still room for a predetermined communication load. The access point 30-2 returns a load status response including that the current communication load is less than a predetermined value to the access point 30-1.

  Based on the load status response received from the access point 30-2, the access point 30-1 detects that there is a margin in the communication load of the access point 30-2, and sends the access point 30-2 to the wireless LAN terminal 20-6. -2 is sent to the user to change the attribution including the identification information of -2. The wireless LAN terminal 20-6 cancels the belonging to the access point 30-1, changes the belonging to the access point 30-2 corresponding to the identification information included in the belonging change instruction, and communicates to the access point 30-2. Send a request. The access point 30-2 detects that there is a margin in the communication load based on the current communication load, and transmits a communication permission to the wireless LAN terminal 20-6. The wireless LAN terminal 20-6 starts communication via the access point 30-2.

  As described above, when the communication load of the access point 30 being affiliated does not have a margin, the wireless LAN terminal 20 starts communication via another access point 30 to which the wireless LAN terminal 20 can belong, so Communication can be started without affecting the communication quality of the LAN terminal 20.

  In the case shown in FIG. 1, when the wireless LAN terminal 20-3 newly starts communication, the wireless LAN terminal 20-3 transmits a communication request to the belonging access point 30-1. In the example shown in FIG. 1, since there are three or more wireless LAN terminals 20 currently in communication, the access point 30-1 transmits a primary request for an AP list to the wireless LAN terminal 20-3. The wireless LAN terminal 20-3 searches for another access point 30 to which it can belong by performing a channel search. However, in the example shown in FIG. 1, since the wireless LAN terminal 20-3 is in a place where it cannot receive radio waves of sufficient strength from other than the access point 30-1, the AP that does not include the identification information of the access point 30 The primary response of the list is transmitted to the access point 30-1.

  When the identification information of the access point 30 is not included in the primary response of the AP list, the access point 30-1 is the wireless LAN terminal 20-4, the wireless LAN terminal 20-5, and the wireless LAN terminal that are currently communicating. The secondary request for the AP list is transmitted to 20-7. Each of the wireless LAN terminal 20-4, wireless LAN terminal 20-5, and wireless LAN terminal 20-7 that has received the secondary request for the AP list creates a secondary response for the AP list by performing a channel search. To the access point 30-1. In the example shown in FIG. 1, the wireless LAN terminal 20-7 creates a secondary response of the AP list including the identification information of the access point 30-2, and the wireless LAN terminal 20-4 and the wireless LAN terminal 20-5 A secondary response of the AP list that does not include the identification information of the access point 30 is created.

  The access point 30-1 transmits a load status request via the wired network 11 to the access point 30-2 having the identification information included in the secondary response of the AP list acquired from the wireless LAN terminal 20-7. In the example illustrated in FIG. 1, the access point 30-2 returns a load status response including that the current communication load is less than a predetermined value to the access point 30-1. Based on the load status response received from the access point 30-2, the access point 30-1 detects that there is a margin in the communication load of the access point 30-2, and sends the access point 30-2 to the wireless LAN terminal 20-7. -2 is sent to the user to change the attribution including the identification information -2.

  The wireless LAN terminal 20-7 cancels the belonging to the access point 30-1, changes the belonging to the access point 30-2 corresponding to the identification information included in the belonging change instruction, and communicates to the access point 30-2. Send a request. The access point 30-2 detects that there is a margin in the communication load based on the current communication load, transmits a communication permission to the wireless LAN terminal 20-7, and the wireless LAN terminal 20-7 Communication continues through 30-2.

  The access point 30-1 transmits a belonging change instruction including the identification information of the access point 30-2 to the wireless LAN terminal 20-7, and then notifies the wireless LAN terminal 20-3 of communication permission. The wireless LAN terminal 20-3 can start communication via the access point 30-1.

  As described above, even when the wireless LAN terminal 20 that starts communication cannot receive radio waves with sufficient strength from the plurality of access points 30, the radio LAN system 10 receives radio waves with sufficient strength from the plurality of access points 30. The wireless LAN terminal 20 is capable of receiving the wireless LAN terminal 20 by changing the attribution of the wireless LAN terminal 20 in communication to another access point 30 without affecting the communication of the other wireless LAN terminal 20. Communication of the terminal 20-3 can be started.

  Hereinafter, functions of the wireless LAN terminal 20 and the access point 30 for realizing the above processing will be described in detail.

  FIG. 2 shows an example of a detailed functional configuration of the wireless LAN terminal 20. The wireless LAN terminal 20 includes a communication data transmission / reception unit 200, a communication request transmission unit 201, an attribution change instruction unit 202, an attribution processing unit 203, an AP list transmission unit 204, and a wireless communication unit 205.

  The wireless communication unit 205 performs wireless communication with the access point 30 based on the wireless LAN. The attribution processing unit 203 executes attribution processing with the nearest access point 30 via the wireless communication unit 205. For example, the attribution processing unit 203 executes attribution processing with the access point 30 having the best reception quality.

  The communication data transmission / reception unit 200 is a block that performs processing related to communication, and converts voice into digital data, performs call processing necessary for voice communication, and the like. Further, when starting communication, the communication data transmitting / receiving unit 200 notifies the communication request transmitting unit 201 to that effect. When the communication permission is received from the access point 30 belonging to the wireless communication unit 205 via the wireless communication unit 205, communication is started via the wireless communication unit 205.

  When the communication request transmitting unit 201 is notified by the communication data transmitting / receiving unit 200 that communication is to be started, the communication request transmitting unit 201 transmits a communication request for inquiring whether communication via the belonging access point 30 is possible to the access point 30 by wireless communication. The data is transmitted via the unit 205.

  When the AP list transmission unit 204 receives a primary request or secondary request for an AP list from the access point 30 to which it belongs, via the wireless communication unit 205, the AP list transmission unit 204 searches for another access point 30 by performing a channel search. Search and create primary response or secondary response of AP list. Then, the AP list transmission unit 204 transmits the primary response or secondary response of the created AP list to the belonging access point 30.

  For example, as shown in data 40 and data 44 in FIG. 3, the AP list transmission unit 204 sets the received signal quality from each other access point 30 associated with the identification information of the other access point 30 searched for. Create a primary response and a secondary response of the AP list that includes them, and transmit them to the access point 30.

  When the attribution change instruction unit 202 receives an attribution change instruction including identification information of the belonging access point 30 from the belonging access point 30, the attribution change instruction unit 202 instructs the attribution processing unit 203 to include the attribution change instruction. The attribution of the identification information to be changed is changed to the access point 30. Then, the belonging change instruction unit 202 instructs the communication request transmitting unit 201 to transmit a communication request to the newly belonging access point 30.

  FIG. 4 shows an example of a detailed functional configuration of the access point 30. The access point 30 includes a load status notification unit 300, a wired communication unit 301, a load status request unit 302, an attribution change instruction transmission unit 303, a communication load determination unit 304, a communication availability transmission unit 305, a wireless communication unit 306, and a communication load calculation unit. 307 and an attribution processing unit 308.

  The wireless communication unit 306 performs wireless communication based on the wireless LAN with the wireless LAN terminal 20, sends communication data received from the wireless LAN terminal 20 to the wired communication unit 301, and wirelessly communicates communication data received from the wired communication unit 301. To the wireless LAN terminal 20. In addition, the wireless communication unit 306 communicates when the subordinate wireless LAN terminal 20 starts communication via the own access point 30 and when the wireless LAN terminal 20 that is communicating through the own access point 30 communicates. When the process is completed, the communication load calculation unit 307 is notified of this. The wired communication unit 301, the load status request unit 302, the attribution change instruction transmission unit 303, the communication enable / disable transmission unit 305, and the attribution processing unit 308 perform transmission / reception of communication data with the wireless LAN terminal 20 via the wireless communication unit 306.

  The wired communication unit 301 performs wired communication with other communication devices 12 and the like via the wired network 11 based on, for example, Ethernet (registered trademark). The attribution processing unit 308 executes attribution processing with the wireless LAN terminal 20 via the wireless communication unit 306.

  The communication load calculation unit 307 calculates a communication load generated at the own access point 30 by wireless communication via the own access point 30 of the wireless LAN terminal 20 belonging to the own access point 30. In the present embodiment, the communication load calculation unit 307 manages the number of wireless LAN terminals 20 currently in communication via the own access point 30 based on information from the wireless communication unit 306. Then, the communication load calculation unit 307 multiplies the number of wireless LAN terminals 20 in communication via the own access point 30 by a communication load calculated in advance for each wireless LAN terminal 20 as voice communication. The current communication load of the own access point 30 is simply calculated.

  The communication load determination unit 304 stores a predetermined communication load value, refers to the current communication load of the own access point 30 calculated by the communication load calculation unit 307, and refers to the current own access point 30. Is determined to be less than a predetermined value, and the determination result is notified to the communication availability transmission unit 305 and the load status notification unit 300.

  When receiving a communication request from the wireless LAN terminal 20, the communication enable / disable transmitting unit 305 instructs the communication load determining unit 304 to determine whether or not the current communication load of the own access point 30 is less than a predetermined value. Let it be judged. When the communication load of the current access point 30 is less than a predetermined value, the communication permission / inhibition transmission unit 305 transmits a communication permission to the wireless LAN terminal 20 that has transmitted the communication request. Further, the communication permission / inhibition transmission unit 305 transmits the communication permission to the instructed wireless LAN terminal 20 even when the attribution change instruction transmission unit 303 is instructed to transmit the communication permission.

  On the other hand, when the communication load of the current access point 30 is equal to or greater than a predetermined value, the communication availability transmission unit 305 transmits the primary request for the AP list to the wireless LAN terminal 20 that has transmitted the communication request. Further, when instructed from the load status request unit 302, the communication availability transmission unit 305 transmits a secondary request for an AP list to the wireless LAN terminal 20 that is currently communicating via the own access point 30. For example, as shown in the data 43 in FIG. 3, the communication propriety transmission unit 305 transmits a secondary request for an AP list including identification information (ID) of the wireless LAN terminal 20 that has transmitted the communication request.

  Further, when instructed by the load status requesting unit 302, the communication enable / disable transmitting unit 305 transmits a communication rejection for rejecting communication via its own access point to the wireless LAN terminal 20 that has transmitted the communication request.

  When receiving the primary response of the AP list from the wireless LAN terminal 20, the load status request unit 302 receives the primary request for the load status for inquiring whether the communication load is less than a predetermined value. To the other access point 30 corresponding to the identification information included in the primary response of the AP list that has been sent, via the wired communication unit 301. For example, as illustrated in data 41 of FIG. 3, the load status request unit 302 creates and transmits a primary request for load status including identification information of the wireless LAN terminal 20 that has transmitted the communication request.

  Then, the load status request unit 302 receives the primary response of the load status including that the communication load is equal to or greater than a predetermined value, and includes the load status including that the communication load is less than the predetermined value. If the primary response is not received, the communication enable / disable transmission unit 305 is instructed to transmit the secondary request for the AP list to the other wireless LAN terminal 20 in communication via the own access point 30. In the primary response of the load status, for example, as shown in the data 42 of FIG. 3, the identification information of the wireless LAN terminal 20 that has transmitted the communication request, the identification information of the access point 30 that has notified the load status, and the load status Is included.

  When the identification information of the other access point 30 is not included in the primary request of the AP list, the load status request unit 302 instructs the communication availability transmission unit 305 to transmit the secondary request of the AP list. .

  Further, when the secondary response of the AP list is received from the wireless LAN terminal 20, the load status request unit 302 corresponds to the identification information included in the secondary response of the received AP list when receiving the secondary request of the load status. To the other access point 30 to be transmitted via the wired communication unit 301. In the secondary request for the load status, for example, as shown in the data 45 of FIG. 3, the identification information of the wireless LAN terminal 20 that transmitted the communication request and the wireless LAN terminal 20 that transmitted the secondary response of the AP list is included. included.

  Then, the load status request unit 302 receives the secondary response of the load status including that the communication load is equal to or greater than a predetermined value, and includes the load status including that the communication load is less than the predetermined value. If the secondary response is not received, the communication enable / disable transmission unit 305 is instructed to transmit a communication rejection to the wireless LAN terminal 20 that has transmitted the secondary request of the AP list. For example, as shown in the data 46 of FIG. 3, the secondary response of the load status includes the identification information of the wireless LAN terminal 20 that has transmitted the communication request. A communication rejection is transmitted to the wireless LAN terminal 20 corresponding to.

  When the load status notification unit 300 receives a primary request or a secondary request for a load status from another access point 30 via the wired communication unit 301, the load status notification unit 300 instructs the communication load determination unit 304 to It is determined whether or not the communication load of the own access point 30 is less than a predetermined value. Then, the load status notifying unit 300 sends the primary response or secondary response of the AP list including the determination result to the other access point 30 that has transmitted the primary request or secondary request of the load status to the wired communication unit. Reply via 301.

  When the attribution change instruction transmission unit 303 receives a primary response of a load situation including that the communication load is less than a predetermined value, the attribution change instruction transmission unit 303 changes the attribution to the access point 30 that has transmitted the primary response of the load situation. An attribution change instruction to be transmitted is transmitted to the wireless LAN terminal 20 that has transmitted the communication request. The attribution change instruction includes, for example, identification information of the access point 30 that is the attribution change destination, as shown in the data 47 of FIG.

  Here, when the primary response of the load situation including that the communication load is less than the predetermined value is received from the plurality of access points 30, the belonging change instruction transmission unit 303 displays the primary response of the load situation. The primary response of the corresponding AP list is acquired from the load status request unit 302. Then, the belonging change instruction transmitting unit 303 has the best received signal quality among the plurality of access points 30 that have received the primary response of the load situation including that the communication load is less than a predetermined value. 30 identification information is extracted, and an attribution change instruction is created using the extracted identification information as identification information of the access point 30 that is the attribution change destination. Then, the attribution change instruction transmission unit 303 transmits the created attribution change instruction to the wireless LAN terminal 20 that has transmitted the communication request included in the primary response of the load status.

  For example, the attribution change instruction transmission unit 303 obtains the primary response of the AP list having the same identification information of the wireless LAN terminal 20 that has transmitted the communication request from the load status request unit 302, thereby The primary response of the AP list corresponding to the primary response is acquired from the load status request unit 302.

  Further, when receiving a secondary response of a load situation including that the communication load is less than a predetermined value, the attribution change instruction transmission unit 303 belongs to the access point 30 that has transmitted the secondary response of the load situation. Is transmitted to the wireless LAN terminal 20 that has transmitted the secondary response of the AP list corresponding to the secondary response of the load status, and communication permission is transmitted to the wireless LAN terminal 20 that has transmitted the communication request. Send.

  FIG. 5 is a flowchart showing an example of the operation of the wireless LAN terminal 20. For example, at a predetermined timing such as when the power is turned on, the wireless LAN terminal 20 starts the processing shown in this flowchart.

  First, the attribution processing unit 203 determines which access point 30 can be attributed by performing a channel search or the like (S100). If the attribution is not possible (S100: No), the attribution processing unit 203 repeats step 100 until the attribution is possible.

  When the attribution is possible (S100: Yes), the attribution processing unit 203 performs an attribution process such as authentication (S101). Then, the communication data transmitting / receiving unit 200 determines whether to start communication (S102). When the communication is not started (S102: No), the belonging processing unit 203 continues the belonging state including the handover process accompanying the movement (S103), and the communication data transmitting / receiving unit 200 performs the process shown in Step 102 again. Do.

  When communication is started (S102: Yes), the wireless LAN terminal 20 executes pre-communication processing for determining an access point 30 as a communication relay destination (S120). When the wireless LAN terminal 20 can determine the relay destination access point 30, the wireless LAN terminal 20 starts communication via the determined access point 30 and changes the relay destination access point 30 during communication. (S130) and step 102 or step 120 is executed again.

  FIG. 6 is a flowchart illustrating an example of detailed processing in step 120. When communication is started (S102: Yes), the communication request transmission unit 201 receives a communication start instruction from the communication data transmission / reception unit 200, and transmits a communication request to the access point 30 belonging to (S121). Then, the communication data transmitting / receiving unit 200 determines whether or not a communication permission has been received (S122). When the communication permission is received (S122: Yes), the wireless LAN terminal 20 executes the process shown in step 130.

  When the communication permission has not been received (S122: No), the communication data transmitting / receiving unit 200 determines whether a communication rejection has been received (S123). When the communication rejection is received (S123: Yes), the communication data transmitting / receiving unit 200 notifies the user of the wireless LAN terminal 20 of an error (S124), and executes the process shown in step 102 again.

  When the communication rejection has not been received (S123: No), the attribution change instruction unit 202 determines whether or not an attribution change instruction has been received (S125). When an attribution change instruction is received (S125: Yes), attribution cancellation processing is executed with the belonging access point 30, and new attribution is performed on the access point 30 corresponding to the identification information included in the attribution change instruction ( S126), the communication request transmission unit 201 executes the process shown in step 121 again.

  If an attribution change instruction has not been received (S125: No), the AP list transmission unit 204 determines whether or not an AP list primary request has been received (S127). When the primary request for the AP list has not been received (S127: No), the communication request transmission unit 201 executes the process shown in step 121 again. When the AP list primary request is received (S127: Yes), the AP list transmission unit 204 executes a channel search or the like to create an AP list primary response. Then, the AP list transmission unit 204 transmits the created primary response of the AP list to the access point 30 belonging to (S128), and the communication request transmission unit 201 executes the process shown in step 121 again.

  FIG. 7 is a flowchart showing an example of detailed processing of step 130. When the communication permission is received (S122: Yes), the communication data transmitting / receiving unit 200 determines whether the communication data is received (S131). When the communication data is received (S131: Yes), the communication data transmitting / receiving unit 200 processes the received communication data (S132), and executes the process shown in step 131 again.

  If communication data has not been received (S131: No), the AP list transmission unit 204 determines whether or not a secondary request for an AP list has been received (S133). When the secondary request for the AP list is received (S133: Yes), the AP list transmission unit 204 executes a channel search or the like to create a secondary response for the AP list. Then, the AP list transmitting unit 204 transmits the created secondary response of the AP list to the communicating access point 30 (S134), and the communication data transmitting / receiving unit 200 executes the process shown in step 131 again.

  When the secondary request for the AP list has not been received (S133: No), the attribution change instruction unit 202 determines whether an attribution change instruction has been received (S135). When an attribution change instruction is received (S135: Yes), the attribution processing unit 203 executes attribution cancellation processing with the access point 30 that is belonging to the access point 30 corresponding to the identification information included in the attribution change instruction. New attribution is performed (S136), and the communication request transmission unit 201 executes the process shown in step 121 again.

  When the attribution change instruction has not been received (S135: No), the communication data transmitting / receiving unit 200 determines whether there is data to be transmitted (S137). If there is data to be transmitted (S137: Yes), the communication data transmitting / receiving unit 200 transmits the data (S138) and executes the process shown in step 131 again. When there is no data to be transmitted (S137: No), the communication data transmitting / receiving unit 200 determines whether to end the communication (S139). When the communication is to be ended (S139: Yes), the communication data transmitting / receiving unit 200 executes the process shown in step 102 again. When the communication is continued (S139: No), the communication data transmitting / receiving unit 200 executes the process shown in step 131 again.

  FIG. 8 and FIG. 9 are flowcharts showing an example of the operation of the access point 30. For example, at a predetermined timing such as when the power is turned on, the access point 30 executes the processing shown in this flowchart.

  First, the attribution processing unit 308 determines whether an attribution request has been received (S200). When the attribution request is received (S200: Yes), the attribution processing unit 308 executes processing necessary for attribution such as authentication (S201), and executes Step 200 again.

  When the attribution request has not been received (S200: No), the communication enable / disable transmission unit 305 determines whether a communication request has been received (S202). When a communication request is received (S202: Yes), the communication load calculation unit 307 determines whether or not the current communication load of the own access point 30 is less than a predetermined value (S203).

  When the communication load is less than a predetermined value (S204: Yes), the communication availability transmission unit 305 returns a communication permission (S204). The wireless communication unit 306 detects the communication started by the wireless LAN terminal 20 that has received the communication permission, and notifies the communication load calculation unit 307 that the belonging wireless LAN terminal 20 has newly started communication. . The communication load calculation unit 307 updates the number of wireless LAN terminals 20 currently in communication (S205), and the attribution processing unit 308 executes Step 200 again.

  When the communication load is equal to or greater than a predetermined value (S204: No), the communication availability transmission unit 305 returns a primary request of the AP list to the wireless LAN terminal 20 that has transmitted the communication request (S206). The processing unit 308 executes Step 200 again.

  When a communication request has not been received (S202: No), the load status request unit 302 determines whether a primary response of the AP list has been received (S207). When the primary response of the AP list is received (S207: Yes), the load status requesting unit 302 determines whether or not the identification information of the other access point 30 is included in the received primary response of the AP list. Is determined (S208).

  When identification information of another access point 30 is included in the received primary response of the AP list (S208: Yes), the load status request unit 302 is included in the primary response of the AP list. The load request primary request is transmitted to the access point 30 corresponding to the identification information via the wired communication unit 301 (S209), and the attribution processing unit 308 executes step 200 again. In step 209, when the identification information of the plurality of access points 30 is included in the primary response of the AP list, the load status request unit 302 sends the load status to the access point 30 corresponding to each identification information. Send primary request.

  When the received primary response of the AP list does not include the identification information of the other access point 30 (S208: No), the load status request unit 302 instructs the communication availability transmission unit 305 to indicate the AP list. The secondary request is transmitted to the other wireless LAN terminal 20 currently communicating via the own access point 30 (S210), and the attribution processing unit 308 executes Step 200 again.

  When the primary response of the AP list has not been received (S207: No), the load status request unit 302 and the belonging change instruction transmission unit 303 have received the primary response of the load status from the other access point 30 or not. Is determined (S211). When the primary response of the load situation is received (S211: Yes), the load situation request unit 302 and the attribution change instruction transmission unit 303 determine the current communication load in the received primary response of the load situation. It is determined whether or not it is less than the value (S212).

  When the primary response of the load situation including the fact that the current communication load is less than a predetermined value is received (S212: Yes), the belonging change instruction transmission unit 303 determines that the current communication load is predetermined. Wireless LAN that has transmitted a communication request with an attribute change instruction that uses the identification information of the access point 30 that has transmitted the primary response of the load status including that it is less than the specified value as the identification information of the access point 30 that is the attribute change destination The transmission is transmitted to the terminal 20 (S213), and the attribution processing unit 308 executes Step 200 again.

  In step 213, when the primary response of the load situation including that the communication load is less than the predetermined value is received from the plurality of access points 30, the attribution change instruction transmission unit 303 displays the primary response of the load situation. 1 is acquired from the load status request unit 302. Then, the belonging change instruction transmitting unit 303 has the best received signal quality among the plurality of access points 30 that have received the primary response of the load situation including that the communication load is less than a predetermined value. 30 identification information is extracted, and an attribution change instruction is created using the extracted identification information as identification information of the access point 30 that is the attribution change destination.

  When the primary response of the load situation including the fact that the current communication load is less than a predetermined value is not received (S212: No), the load situation request unit 302 sends to the communication availability transmission unit 305. Then, the secondary request for the AP list is transmitted to another wireless LAN terminal 20 that is currently communicating via the own access point 30 (S214), and the attribution processing unit 308 executes Step 200 again.

  When the primary response of the load status has not been received (S211: No), the load status request unit 302 determines whether or not the secondary response of the AP list has been received (S215). When the secondary response of the AP list is received (S215: Yes), the load status requesting unit 302 determines whether or not the identification information of the other access point 30 is included in the received secondary response of the AP list. Is determined (S216).

  When the received secondary response of the AP list includes identification information of another access point 30 (S216: Yes), the load status request unit 302 is included in the secondary response of the AP list. A secondary request for the load status is transmitted to the access point 30 corresponding to the identification information via the wired communication unit 301 (S217), and the attribution processing unit 308 executes Step 200 again. In step 217, if the identification list information of the plurality of access points 30 is included in the secondary response of the AP list, the load status requesting unit 302 sends the load status to the access point 30 corresponding to each identification information. Send a secondary request.

  When the received secondary response of the AP list does not include the identification information of the other access point 30 (S216: No), the load status request unit 302 instructs the communication availability transmission unit 305 to reject communication. Is transmitted to the wireless LAN terminal 20 that has transmitted the communication request (S218), and the attribution processing unit 308 executes Step 200 again.

  When the secondary response of the AP list has not been received (S215: No), the load status request unit 302 and the attribution change instruction transmission unit 303 have received the secondary response of the load status from the other access point 30 or not. Is determined (S219). When the secondary response of the load status is received (S219: Yes), the load status request unit 302 and the attribution change instruction transmission unit 303 determine the current communication load in the received secondary response of the load status. It is determined whether or not it is less than the value (S220).

  When the secondary response of the load situation including the fact that the current communication load is less than a predetermined value is received (S220: Yes), the belonging change instruction transmission unit 303 determines that the current communication load is predetermined. Wireless LAN that has transmitted a communication request with an attribute change instruction that uses the identification information of the access point 30 that has transmitted the secondary response of the load status including that it is less than the specified value as the identification information of the access point 30 that is the attribute change destination It transmits to the terminal 20 (S221). Then, the attribution change instruction transmission unit 303 instructs the communication enable / disable transmission unit 305 to transmit a communication permission to the wireless LAN terminal 20 that has transmitted the communication request (S222), and the attribution processing unit 308 performs step 200 again. Execute.

  In step 221, when a secondary response of a load situation including that the communication load is less than a predetermined value is received from a plurality of access points 30, the attribution change instruction transmission unit 303 receives the secondary response of the load situation. The secondary response of the AP list corresponding to the response is acquired from the load status request unit 302. Then, the attribution change instruction transmission unit 303 has the best received signal quality among the plurality of access points 30 that have received the secondary response of the load status including that the communication load is less than a predetermined value. 30 identification information is extracted, and an attribution change instruction is created using the extracted identification information as identification information of the access point 30 that is the attribution change destination.

  When the secondary response of the load status including that the current communication load is less than a predetermined value is not received (S220: No), the load status request unit 302 sends the communication status transmission unit 305 to the communication enable / disable transmission unit 305. Instructing it causes the wireless LAN terminal 20 that has transmitted the communication request to transmit a communication rejection (S223), and the attribution processing unit 308 executes Step 200 again.

  FIG. 10 is a sequence diagram illustrating an example of the operation of the wireless LAN system 10. The sequence shown in FIG. 10 shows a case where the wireless LAN terminal 20 starts communication via the access point 30 with a sufficient communication load.

  First, the wireless LAN terminal 20 transmits an attribution request to the nearest access point 30 (S300), and executes attribution processing with the access point 30 (S301). Then, the wireless LAN terminal 20 transmits a communication request to the access point 30 to which the wireless LAN terminal 20 belongs (S302). The access point 30 that has received the communication request determines the current communication load (S303), and returns a communication permission (S304). Then, the wireless LAN terminal 20 communicates with the communication device 12 via the access point 30 (S305).

  In this way, when the wireless LAN terminal 20 to which the access point 30 belongs starts communication, the access point 30 determines whether communication is possible based on its current communication load. The influence on the communication quality of the terminal 20 can be reduced, and more wireless LAN terminals 20 can be attributed to themselves.

  FIG. 11 is a sequence diagram illustrating an example of the operation of the wireless LAN system 10. In the sequence shown in FIG. 11, the wireless LAN terminal 20 in a position where it can receive radio waves with sufficient strength to belong from a plurality of access points 30 is attributed to the access point 30 where there is no margin in the current communication load. In this example, when communication is started, a change in attribution is instructed to another access point 30 having a sufficient communication load. In FIG. 11, the processes denoted by the same reference numerals as those in FIG. 10 are the same processes as the processes described in FIG. 10, and thus the description is omitted except for the points described below.

  The access point 30-1 that has received the communication request determines the current communication load (S303), detects that its current communication load is equal to or greater than a predetermined value, and has transmitted the communication request. An AP list primary request is returned to the wireless LAN terminal 20 (S310). The wireless LAN terminal 20 performs a channel search or the like, creates an AP list primary response (S311), and transmits the created AP list primary response to the access point 30-1 (S312).

  The access point 30-1 determines whether the identification information of the access point 30 is included in the primary response of the received AP list (S313), and the identification included in the primary response of the AP list A primary request for the load status is transmitted via the wired network 11 to the access point 30-2 corresponding to the information (S314). The access point 30-2 that has received the primary request for the load status determines the current communication load (S315), detects that the current communication load is less than a predetermined value, and includes that effect. The primary response of the load status is transmitted to the access point 30-1 (S316).

  Similarly, the access point 30-1 transmits the primary request of the load status via the wired network 11 to the access point 30-3 corresponding to the identification information included in the primary request of the AP list. (S317). The access point 30-3 that has received the primary request for the load status determines the current communication load (S318), detects that the current communication load is less than a predetermined value, and includes that effect. The primary response of the load status is transmitted to the access point 30-1 (S319).

  If the access point 30-1 receives the primary response of the load status from all the access points 30 that have transmitted the primary request of the load status, the access point 30-1 determines whether or not there is an access point 30 with a sufficient communication load. Determine (S320). When there are a plurality of access points 30 with sufficient communication load (in this example, access point 30-2 and access point 30-3), the access point 30-1 returns the primary response of the AP list received in step 312. Referring to the wireless LAN terminal 20, an access change instruction is sent to the access point 30 having the best received signal quality (access point 30-3 in this example) as the change destination of the access (S321).

  The wireless LAN terminal 20 performs a process of canceling the attribution with the access point 30-1 (S322), transmits an attribution request to the access point 30-3 (S323), and performs an attribution process with the access point 30-3. Is executed (S324). Thereafter, the wireless LAN terminal 20 transmits a communication request to the access point 30-3 (S325). The access point 30-3 determines its own communication load (S326), and transmits a communication permission to the wireless LAN terminal 20 (S327). The wireless LAN terminal 20 communicates with the communication device 12 via the access point 30-3.

  FIG. 12 is a sequence diagram illustrating an example of the operation of the wireless LAN system 10. In the sequence shown in FIG. 12, the wireless LAN terminal 20-2 belongs to the access point 30 that has no sufficient communication load, and receives radio waves with sufficient strength to belong from other than the access point 30. When the wireless LAN terminal 20-2 starts communication when the wireless LAN terminal 20-2 starts communication when the wireless LAN terminal 20-2 is in a position where the communication cannot be performed, the wireless LAN terminal 20-1 is changed to belong to another access point 30 with a sufficient communication load An example is shown. In FIG. 12, the processes denoted by the same reference numerals as those in FIG. 10 or FIG. 11 are the same processes as those described in FIG. 10 or FIG.

  In step 313, the access point 30-1 detects that the identification information of the access point 30 is not included in the primary response of the received AP list, and sends the AP list to the currently communicating wireless LAN terminal 20-1. The secondary request is transmitted (S330). The wireless LAN terminal 20-1 that has received the secondary request for the AP list performs a channel search or the like to create a secondary response for the AP list (S331), and sends the secondary response for the created AP list to the access point 30-. 1 is transmitted (S332).

  The access point 30-1 determines whether or not the identification information of the access point 30 is included in the secondary response of the received AP list (S333), and the identification included in the secondary response of the AP list A secondary request for the load status is transmitted via the wired network 11 to the access point 30-2 corresponding to the information (S334). The access point 30-2 that has received the secondary request for the load status determines the current communication load (S335), detects that the current communication load is less than a predetermined value, and includes that effect. A secondary response of the load status is transmitted to the access point 30-1 (S336).

  Similarly, the access point 30-1 transmits the secondary request for the load status via the wired network 11 to the access point 30-3 corresponding to the identification information included in the secondary request in the AP list. (S337). The access point 30-3 that has received the secondary request for the load status determines the current communication load (S338), detects that the current communication load is less than a predetermined value, and includes that effect. A secondary response of the load status is transmitted to the access point 30-1 (S339).

  If the access point 30-1 receives the secondary response of the load status from all the access points 30 that have transmitted the secondary request of the load status, the access point 30-1 determines whether there is an access point 30 with a sufficient communication load. Determine (S340). When there are a plurality of access points 30 with sufficient communication load (in this example, access point 30-2 and access point 30-3), the access point 30-1 returns the secondary response of the AP list received in step 332 With reference to the access point 30 having the best received signal quality, an attribution change instruction is sent to the wireless LAN terminal 20-1 with the attribution change destination (S341).

  The wireless LAN terminal 20-1 performs a process of canceling the attribution with the access point 30-1 (S342), transmits an attribution request to the access point 30 included in the attribution change instruction, and communicates with the access point 30. Execute attribution process. Then, after the belonging process is completed, the wireless LAN terminal 20-1 transmits a communication request and resumes communication.

  Next, the access point 30-1 transmits a communication permission to the wireless LAN terminal 20-2 (S343). Then, the wireless LAN terminal 20-2 starts communication with the communication device 12 via the access point 30-1 (S344).

  The embodiment of the present invention has been described above.

  As is clear from the above description, according to the wireless LAN system 10 of the present embodiment, communication is started to more wireless LAN terminals 20 without affecting the communication quality of other wireless LAN terminals 20 in communication. In addition, more wireless LAN terminals 20 can be attributed to one access point 30.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary.

  13 and 14 are flowcharts illustrating another example of the operation of the wireless LAN terminal 20. When there is an incoming call, the wireless LAN terminal 20 of the present embodiment executes different processing depending on whether the incoming call is a group incoming call. In the present embodiment, SIP (Session Initiation Protocol) will be described as an example of a call control procedure.

  First, the communication data transmitting / receiving unit 200 determines whether an INVITE request has been received (S400). When the INVITE request has not been received (S400: No), the communication data transmitting / receiving unit 200 repeats Step 400 until the INVITE request is received.

  When receiving the INVITE request (S400: Yes), the communication data transmitting / receiving unit 200 determines whether the INVITE request indicates a group incoming call based on the information in the INVITE request (S401). When the incoming call is a group incoming call (S401: Yes), the communication data transmitting / receiving unit 200 transmits a 180 RINGING response (S402) and determines whether or not an off-hook has been detected (S403).

  When the off-hook is not detected (S403: No), the communication data transmitting / receiving unit 200 determines whether a CANCEL request has been received (S410). When the CANCEL request has not been received (S410: No), the communication data transmitting / receiving unit 200 executes the process shown in step 403 again. When the CANCEL request is received (S410: Yes), the communication data transmitting / receiving unit 200 transmits a 200 OK response (S411), and the wireless LAN terminal 20 ends the process illustrated in this flowchart.

  When an off-hook is detected (S403: Yes), the communication request transmission unit 201 transmits a communication request (S404). Then, the AP list transmission unit 204 determines whether or not an AP list primary request has been received (S405). If the primary request for the AP list has not been received (S405: No), the communication data transmitting / receiving unit 200 executes the process shown in step 407.

  When the AP list primary request is received (S405: Yes), the AP list transmission unit 204 performs a channel search or the like to create and transmit an AP list primary response (S406). Then, the communication data transmitting / receiving unit 200 determines whether a communication permission has been received (S407). When the communication permission is received (S407: Yes), the communication data transmitting / receiving unit 200 transmits a 200OK response (S408) and starts communication.

  When the communication permission is not received (S407: No), the attribution processing unit 203 determines whether or not an attribution change instruction is received (S409). When the attribution change instruction is received (S409: Yes), the attribution processing unit 203 changes the attribution to the instructed access point 30, and the communication request transmitting unit 201 executes the process shown in step 404 again. When the attribution change instruction has not been received (S409: No), the communication data transmitting / receiving unit 200 executes the process shown in step 407 again.

  In step 401, when it is not a group incoming call (S401: No), the communication request transmission unit 201 transmits a communication request (S412). Then, the AP list transmission unit 204 determines whether or not an AP list primary request has been received (S413). If the primary request for the AP list has not been received (S413: No), the communication data transmitting / receiving unit 200 executes the process shown in step 415.

  When the AP list primary request is received (S413: Yes), the AP list transmission unit 204 performs a channel search or the like to create and transmit an AP list primary response (S414). Then, the communication data transmitting / receiving unit 200 determines whether or not the communication permission has been received (S415). When the communication permission is received (S415: Yes), the communication data transmitting / receiving unit 200 transmits a 180 RINGING response (S416), and determines whether or not an off-hook is detected (S417).

  When the off-hook is detected (S417: Yes), the communication data transmitting / receiving unit 200 transmits a 200OK response (S418) and starts communication. When the off-hook is not detected (S417: No), the communication data transmitting / receiving unit 200 determines whether a CANCEL request is received (S420). When the CANCEL request has not been received (S420: No), the communication data transmitting / receiving unit 200 executes the process shown in step 417 again. When the CANCEL request is received (S420: Yes), the communication data transmission / reception unit 200 transmits a 200OK response (S421), and the wireless LAN terminal 20 ends the processing shown in this flowchart.

  When the communication permission is not received in step 415 (S415: No), the attribution processing unit 203 determines whether or not an attribution change instruction is received (S419). When the attribution change instruction is received (S419: Yes), the attribution processing unit 203 changes the attribution to the instructed access point 30, and the communication request transmission unit 201 executes the process shown in Step 412 again. When the attribution change instruction has not been received (S419: No), the communication data transmitting / receiving unit 200 executes the process shown in step 415 again.

  FIG. 15 is a sequence diagram illustrating an example of the operation of the wireless LAN system 10 in the group incoming call. First, the wireless LAN terminal 20-1, the wireless LAN terminal 20-2, and the wireless LAN terminal 20-n execute processing for belonging to the access point 30 (S500, S501, S502).

  When the INVITE request is transmitted from the external communication device 12 to the relay server 14 (S503), the relay server 14 sends an INVITE request including a group incoming call via the access point 30 to the wireless LAN terminal 20-1. And transmitted to the wireless LAN terminal 20-2 and the wireless LAN terminal 20-n (S504, S505, S506). Each of the wireless LAN terminal 20-1, the wireless LAN terminal 20-2, and the wireless LAN terminal 20-n detects that it is a group incoming call from the received INVITE request, and relays a 180 RINGING response via the access point 30. It transmits to the server 14 (S507, S508, S509). The relay server 14 transmits a 180 RINGING response to the communication device 12.

  When one of the plurality of wireless LAN terminals 20 constituting the group (in this example, the wireless LAN terminal 20-1) responds to the incoming call (S511), the wireless LAN terminal 20-1 makes a communication request. Is transmitted to the access point 30 (S512). The access point 30 determines its current communication load (S513), and transmits a communication permission to the wireless LAN terminal 20-1 (S514).

  The wireless LAN terminal 20-1 transmits a 200 OK response to the relay server 14 via the access point 30 (S515). The relay server 14 transmits a CANCEL request to other wireless LAN terminals 20 constituting the group other than the wireless LAN terminal 20-1 (S516, S518), and receives a 200 OK response (S517, S519). Then, the relay server 14 transmits a 200 OK response to the communication device 12 (S520), and the wireless LAN terminal 20-1 and the communication device 12 start communication via the access point 30 and the relay server 14 (S521). ).

1 is a system configuration diagram showing an example of a configuration of a wireless LAN system 10 according to an embodiment of the present invention. 2 is a block diagram illustrating an example of a detailed functional configuration of a wireless LAN terminal 20. FIG. 2 is an explanatory diagram illustrating an example of a configuration of data transmitted / received in a wireless LAN system 10. FIG. 3 is a block diagram illustrating an example of a detailed functional configuration of an access point 30. FIG. 4 is a flowchart showing an example of the operation of the wireless LAN terminal 20. 7 is a flowchart showing an example of detailed processing in step 120. 7 is a flowchart showing an example of detailed processing in step 130. 3 is a flowchart showing an example of the operation of an access point 30. 3 is a flowchart showing an example of the operation of an access point 30. 4 is a sequence diagram illustrating an example of an operation of the wireless LAN system 10. FIG. 4 is a sequence diagram illustrating an example of an operation of the wireless LAN system 10. FIG. 4 is a sequence diagram illustrating an example of an operation of the wireless LAN system 10. FIG. 6 is a flowchart showing another example of the operation of the wireless LAN terminal 20. 6 is a flowchart showing another example of the operation of the wireless LAN terminal 20. It is a sequence diagram which shows an example of operation | movement of the wireless LAN system 10 in group incoming.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Wireless LAN system, 11 ... Wired network, 12 ... Communication equipment, 13 ... Communication area, 14 ... Relay server, 20 ... Wireless LAN terminal, 200 ... Communication data Transmission / reception unit, 201 ... communication request transmission unit, 202 ... attribution change instruction unit, 203 ... attribution processing unit, 204 ... AP list transmission unit, 205 ... wireless communication unit, 30 ... Access point 300 ... Load status notification unit 301 ... Wired communication unit 302 ... Load status request unit 303 ... Attribution change instruction transmission unit 304 ... Communication load determination unit 305 ..Communication availability transmission unit, 306... Wireless communication unit, 307... Communication load calculation unit, 308... Attribution processing unit, 40, 41, 42, 43, 44, 45, 46, 47. data

Claims (4)

A wireless LAN system comprising a plurality of access points and a plurality of wireless LAN terminals,
Each of the plurality of wireless LAN terminals is
A terminal side attribution processing means that performs attribution processing with the nearest access point,
Prior to data communication via the belonging access point, a communication request transmitting means for transmitting to the access point a communication request for inquiring whether data communication via the access point is possible,
In response to the communication request, when a communication permission for permitting data communication via the access point is acquired from the access point, data communication means for performing data communication via the access point by wireless communication ;
A primary or secondary request for an AP list in which the received signal quality from the access point is associated with the identification information of the access point receiving the radio wave of sufficient strength to belong is received from the belonging access point An AP list transmission means for searching for another access point to create the AP list, and transmitting the created AP list to the access point to which it belongs,
When an attribution change instruction including identification information of the belonging access point is received from the belonging access point, the terminal side attribution processing means is instructed to the identification information access point included in the attribution change instruction. After changing the attribution, the communication request transmission means is instructed to have the attribution change instruction means to transmit the communication request to the newly attributed access point , and
Each of the plurality of access points is
AP side attribution processing means for performing attribution processing with the wireless LAN terminal;
A communication load calculating means for calculating a communication load generated in the own access point by wireless communication of the wireless LAN terminal belonging to the own access point;
A communication load determination unit that determines whether or not the communication load calculated by the communication load calculation unit is less than a predetermined value when the communication request is received from a wireless LAN terminal belonging to the own access point;
When the communication load determining means determines that the communication load is less than a predetermined value, the communication permission is transmitted to the wireless LAN terminal that has transmitted the communication request, and the communication load is determined in advance. If it is determined that the value above, the communication availability transmitting means for transmitting a primary request for the AP list to the wireless LAN terminal having transmitted the communication request,
When the AP list is received from the wireless LAN terminal belonging to the own access point, a load status primary request for inquiring whether the communication load is less than the predetermined value is displayed in the AP list. Load status requesting means for transmitting to other access points corresponding to the included identification information;
A load including the determination result by causing the communication load determination means to determine whether or not the communication load is less than a predetermined value when receiving a primary or secondary request of the load status from another access point A load status notification means for transmitting a status notification;
When a load status notification including that the communication load is less than a predetermined value is received from another access point, another access with a communication load less than a predetermined value is referred to the AP list. An attribution change instruction transmitting means for transmitting an attribution change instruction including identification information of another access point associated with the highest received signal quality among the points to the wireless LAN terminal that has transmitted the AP list; /> I have a,
The communication availability transmitting means is
When the AP list transmitted from the wireless LAN terminal in response to the primary request for the AP list does not include the identification information of other access points, the other information being communicated through the own access point Send a secondary request for the AP list to the wireless LAN terminal,
The load status request means includes
When receiving the AP list from a wireless LAN terminal in response to the secondary request for the AP list, a secondary request for a load status for inquiring whether the communication load is less than the predetermined value, Send to other access points corresponding to the identification information included in the AP list,
Attribution change instruction transmission means
In response to a secondary request of the AP list, when a load status notification including that the communication load is less than a predetermined value is received from another access point in response to the secondary request of the load situation, With reference to the AP list received from the wireless LAN terminal, identification information of other access points associated with the highest received signal quality among other access points having a communication load less than a predetermined value is obtained. attribution change instruction containing, and transmits to the AP list wireless LAN terminal having transmitted, and instructs the communication availability transmitting unit, to transmit said communication permission to the wireless LAN terminal having transmitted the communication request Rukoto A wireless LAN system characterized by the above.   The wireless LAN system according to claim 1,
  The communication availability transmitting means is
  If there is no load status notification transmitted from another access point in response to the primary request for the load status, including that the communication load is less than a predetermined value, A wireless LAN system, wherein a secondary request for the AP list is transmitted to another wireless LAN terminal in communication via its own access point. An access point that is used in a wireless LAN system and performs wireless communication with a wireless LAN terminal,
AP side attribution processing means for performing attribution processing with the wireless LAN terminal;
A communication load calculating means for calculating a communication load generated in the own access point by wireless communication of the wireless LAN terminal belonging to the own access point;
A communication load determining means for determining whether or not the communication load calculated by the communication load calculating means is less than a predetermined value when a communication request is received from a wireless LAN terminal belonging to the own access point;
When the communication load determining means determines that the communication load is less than a predetermined value, a communication permission is transmitted to the wireless LAN terminal that has transmitted the communication request, and the communication load is determined in advance. When it is determined that the value is equal to or greater than the value, the other access point is included in the identification information of the other access point that is receiving a radio wave having sufficient strength to belong to the wireless LAN terminal that has transmitted the communication request. a communication availability transmitting means for transmitting a primary request AP list that associates reception signal quality from,
When the AP list is received from the wireless LAN terminal belonging to the own access point, a load status primary request for inquiring whether the communication load is less than the predetermined value is displayed in the AP list. Load status requesting means for transmitting to other access points corresponding to the included identification information;
A load including the determination result by causing the communication load determination means to determine whether or not the communication load is less than a predetermined value when receiving a primary or secondary request of the load status from another access point A load status notification means for transmitting a status notification;
When a load status notification including that the communication load is less than a predetermined value is received from another access point, another access with a communication load less than a predetermined value is referred to the AP list. An attribution change instruction transmitting means for transmitting an attribution change instruction including identification information of another access point associated with the highest received signal quality among the points to the wireless LAN terminal that has transmitted the AP list; /> I have a,
The communication availability transmitting means is
When the AP list transmitted from the wireless LAN terminal in response to the primary request for the AP list does not include the identification information of other access points, the other information being communicated through the own access point Send a secondary request for the AP list to the wireless LAN terminal,
The load status request means includes
When receiving the AP list from a wireless LAN terminal in response to the secondary request for the AP list, a secondary request for a load status for inquiring whether the communication load is less than the predetermined value, Send to other access points corresponding to the identification information included in the AP list,
Attribution change instruction transmission means
In response to a secondary request of the AP list, when a load status notification including that the communication load is less than a predetermined value is received from another access point in response to the secondary request of the load situation, With reference to the AP list received from the wireless LAN terminal, identification information of other access points associated with the highest received signal quality among other access points having a communication load less than a predetermined value is obtained. attribution change instruction containing, and transmits to the AP list wireless LAN terminal having transmitted, and instructs the communication availability transmitting unit, to transmit said communication permission to the wireless LAN terminal having transmitted the communication request Rukoto An access point characterized by   The access point according to claim 3,
  The communication availability transmitting means is
  If there is no load status notification transmitted from another access point in response to the primary request for the load status, including that the communication load is less than a predetermined value, An access point, wherein a secondary request for the AP list is transmitted to another wireless LAN terminal in communication via its own access point.

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