JP6806498B2 - Wireless LAN device and communication processing method - Google Patents

Description

The present invention relates to the selection of a wireless LAN access point to which a wireless LAN (Local Area Network) station is connected.

Conventionally, a wireless LAN having a plurality of wireless LAN access points has been known. In such a wireless LAN, the wireless LAN station communicates with a certain wireless LAN access point A. Here, if the wireless LAN station moves and moves away from the wireless LAN access point A, the communication quality deteriorates. In such a case, the wireless LAN station may be close to another wireless LAN access point B. Therefore, if communication is performed with the wireless LAN access point B, deterioration of communication quality can be prevented.

As a technique for detecting that the wireless LAN station is away from the wireless LAN access point A and approaching the wireless LAN access point B, a method having the following steps 1 and 2 is known (for example, (See summary of Patent Document 1 and FIG. 2).

(Step 1) A signal is periodically transmitted from the wireless LAN station to the wireless LAN access points A and B.

(Step 2) The strengths of the signals received by the wireless LAN access points A and B are compared.

In addition, there are Patent Documents 2 to 5 as a conventional technique relating to a wireless LAN.

JP-A-2010-933360 Special Table 2015-510738 Special Table 2008-538260 Japanese Unexamined Patent Publication No. 2006-67178 Japanese Unexamined Patent Publication No. 2010-21765

However, according to the above-mentioned prior art, a plurality of wireless LAN access points have to keep waiting for a signal from a wireless LAN station whose transmission is unknown, which hinders the operation of the plurality of wireless LAN access points. To bring up.

For example, each of a plurality of wireless LAN access points generally provides wireless communication services on different channels in order to avoid congestion in the wireless space. In this case, each of the plurality of wireless LAN access points must match the channel of the signal from the wireless LAN station to the channel of the signal from the wireless LAN station while waiting for the signal from the wireless LAN station, and the provision of the wireless communication service is stopped. Must.

Therefore, an object of the present invention is to detect a wireless LAN access point suitable for wireless communication with a wireless LAN station so as not to hinder the operation of the wireless LAN access point as much as possible.

The wireless LAN device according to the present invention is a response request signal that requests a response from a wireless LAN access point that is wirelessly communicating with the wireless LAN access point. One wireless LAN access point that transmits the above and another wireless LAN access point that is different from the one wireless LAN access point, and waits for the reception of the response according to the time point of transmission of the response request signal. It is a wireless LAN device connected to another wireless LAN access point to be started, and the received signal strength at the time of the wireless communication at the one wireless LAN access point among the other wireless LAN access points. Rather, it is configured to include a wireless LAN access point detection unit that detects a wireless LAN access point having a strong reception signal strength of the response.

The wireless LAN device configured as described above is a wireless LAN access point, and requests a response from a wireless LAN communication terminal that is performing wireless communication with the one wireless LAN access point. A wireless LAN access point for transmitting a response request signal and a wireless LAN access point different from the one wireless LAN access point, waiting for reception of the response to transmit the response request signal. It is connected to another wireless LAN access point that starts according to the time point. Among the other wireless LAN access points, the wireless LAN access point detection unit has a wireless LAN in which the received signal strength of the response is stronger than the received signal strength of the wireless communication at the one wireless LAN access point. Detect the access point.

The wireless LAN device according to the present invention has a transmission instruction unit that instructs one wireless LAN access point to transmit the response request signal, and the other wireless LAN access point waits for reception of the response. It may be provided with a reception standby instruction unit for instructing.

In the wireless LAN device according to the present invention, the standby for receiving the response may be started at the same time as the transmission of the response request signal.

In the wireless LAN device according to the present invention, the standby for receiving the response may be started before the reception of the response by the other wireless LAN access point.

In the wireless LAN device according to the present invention, the standby for receiving the response may be such that the other wireless LAN access point can receive the signal of the channel of the response.

In the wireless LAN device according to the present invention, the response request signal may be ARP Request or Null Data.

The wireless LAN device according to the present invention instructs one wireless LAN access point to disconnect communication with the wireless LAN communication terminal when there is a detection result of the wireless LAN access point detection unit. A communication disconnection instruction unit may be provided.

The wireless LAN device according to the present invention may transmit one of the detection results of the wireless LAN access point detection unit to the wireless LAN communication terminal.

The present invention is a wireless LAN access point that transmits a response request signal requesting a response to a wireless LAN communication terminal that is performing wireless communication with the wireless LAN access point. One wireless LAN access point and another wireless LAN access point different from the one wireless LAN access point, and another wireless LAN access point that starts waiting for reception of the response according to a time point of transmission of the response request signal. It is a communication processing method in a wireless LAN device connected to a wireless LAN access point, and is based on the received signal strength at the time of the wireless communication at the one wireless LAN access point among the other wireless LAN access points. Is also a communication processing method including a wireless LAN access point detection step for detecting a wireless LAN access point having a strong received signal strength of the response.

It is a figure which shows the wireless LAN system which concerns on embodiment of this invention. It is a functional block diagram which shows the structure of the wireless LAN controller (wireless LAN apparatus) 10 which concerns on embodiment of this invention. It is a flowchart which shows the operation of the wireless LAN system which concerns on embodiment of this invention. It is a timing chart which shows the operation of the wireless LAN system which concerns on embodiment of this invention. It is a functional block diagram which shows the operation before the timing t0 of the wireless LAN system which concerns on embodiment of this invention. It is a functional block diagram which shows the operation at the timing t0 of the wireless LAN system which concerns on embodiment of this invention. It is a functional block diagram which shows the operation after the timing t0 of the wireless LAN system which concerns on embodiment of this invention. It is a functional block diagram which shows the operation after the timing t0 of the wireless LAN system which concerns on embodiment of this invention (but after the comparison of received signal strengths).

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

FIG. 1 is a diagram showing a wireless LAN system according to an embodiment of the present invention.

The wireless LAN system according to the embodiment of the present invention includes a wireless LAN controller 10, wireless LAN access points 21, 22, 23, and a wireless LAN station 30. In the drawings, the notation of "wireless LAN" is omitted, and the notation of the controller 10, the access points 21, 22, 23 and the station 30 is used.

The wireless LAN station (wireless LAN communication terminal) 30 is a terminal that performs wireless communication in a wireless LAN system. The wireless LAN station 30 is performing wireless communication with one wireless LAN access point 21. One wireless LAN access point 21 transmits a response request signal (for example, ARP Request or Null Data) requesting a response to the wireless LAN station 30. If the response request signal is an ARP Request, the response is an ARP Reply, and if the response request signal is Null Data, the response is an Ack frame.

The wireless LAN access points (other wireless LAN access points) 22 and 23 are wireless LAN access points different from one wireless LAN access point 21. The other wireless LAN access points 22 and 23 start waiting for the reception of the response according to the time when the response request signal is transmitted. For example, another wireless LAN access points 22 and 23 start waiting for the reception of the response at the same time as the transmission of the response request signal (for example, timing t0).

The wireless LAN access points 21, 22, and 23 each transmit and receive signals of different channels. As a result, congestion in the wireless space between the wireless LAN access points 21, 22, and 23 is avoided.

Further, in the standby for receiving the response, the other wireless LAN access points 22 and 23 can receive the signal of the response channel (the channel used by one wireless LAN access point 21 for transmission / reception). Is. For example, performing RF scan in promiscuous mode on the channel used by one wireless LAN access point 21 for transmission and reception by another wireless LAN access points 22 and 23 corresponds to waiting for reception of a response. To do.

Further, another wireless LAN access point 23, one wireless LAN access point 21, and another wireless LAN access point 22 are arranged in order of proximity to the wireless LAN station 30. Another wireless LAN access point 23 is closest to the wireless LAN station 30.

The wireless LAN controller (wireless LAN device) 10 is connected to one wireless LAN access point 21 and another wireless LAN access points 22 and 23 by a LAN cable. The wireless LAN controller 10 performs wired communication with one wireless LAN access point 21 and another wireless LAN access points 22 and 23.

FIG. 2 is a functional block diagram showing a configuration of a wireless LAN controller (wireless LAN device) 10 according to an embodiment of the present invention. The wireless LAN controller (wireless LAN device) 10 according to the embodiment of the present invention includes a timing designation unit 11, a transmission instruction unit 13, a reception standby instruction unit 15, an RSSI recording unit 12, an RSSI reception unit 14, and an RSSI comparison unit (wireless LAN). An access point detection unit) 16, a candidate selection unit 17, and a communication disconnection instruction unit 18 are provided.

The timing designation unit 11 gives the transmission instruction unit 13 and the reception standby instruction unit 15 the timing t0, which is the time when the response request signal is transmitted and the standby for receiving the response is started.

The transmission instruction unit 13 instructs one wireless LAN access point 21 to transmit a response request signal. Note that this instruction includes timing t0, and one wireless LAN access point 21 transmits a response request signal at this timing t0.

The reception standby instruction unit 15 instructs the other wireless LAN access points 22 and 23 to wait for the response to be received. Note that this instruction includes the timing t0, and the other wireless LAN access points 22 and 23 start waiting for the reception of the response at the time of the timing t0.

The RSSI recording unit 12 records the received signal strength indicator (RSSI) at the time of wireless communication with the wireless LAN station 30 at one wireless LAN access point 21. The received signal strength is measured by one wireless LAN access point 21 during wireless communication between one wireless LAN access point 21 and the wireless LAN station 30.

The RSSI receiving unit 14 receives the received signal strength of the response at the other wireless LAN access points 22 and 23. The received signal strength is measured when the response is received at the other wireless LAN access points 22 and 23, and is received from the other wireless LAN access points 22 and 23.

The RSSI comparison unit (wireless LAN access point detection unit) 16 includes the received signal strength of the response received from the RSSI reception unit 14 at the other wireless LAN access points 22 and 23, and one radio recorded in the RSSI recording unit 12. The strength of the received signal during wireless communication at the LAN access point 21 is compared. Based on this comparison result, the RSSI comparison unit 16 has a response reception signal strength rather than a reception signal strength at the time of wireless communication at one wireless LAN access point 21 among the other wireless LAN access points 22 and 23. Detects a strong wireless LAN access point. In the example of FIG. 1, the detection result is another wireless LAN access point 23.

The candidate selection unit 17 receives the detection result by the RSSI comparison unit 16, selects one of them, and gives the communication disconnection instruction unit 18. The candidate selection unit 17 selects, for example, the detection result obtained by the RSSI comparison unit 16 having the strongest received signal strength of the response. In the example of FIG. 1, since the detection result by the RSSI comparison unit 16 is only another wireless LAN access point 23, the candidate selection unit 17 selects another wireless LAN access point 23.

The communication disconnection instruction unit 18 is a wireless LAN station for a certain wireless LAN access point 21 when the candidate selection unit 17 selects some candidate (meaning that there is a detection result by the RSSI comparison unit 16). (Wireless LAN communication terminal) Instructs to disconnect communication with 30. The communication disconnection instruction unit 18 may transmit the candidate selected by the candidate selection unit 17 (one of the detection results by the RSSI comparison unit 16) to the wireless LAN station 30.

Next, the operation of the embodiment of the present invention will be described.

FIG. 3 is a flowchart showing the operation of the wireless LAN system according to the embodiment of the present invention. In FIG. 3, the operation is shown separately for the wireless LAN controller 10, one wireless LAN access point 21, another wireless LAN access point 22, 23, and the wireless LAN station 30.

FIG. 4 is a timing chart showing the operation of the wireless LAN system according to the embodiment of the present invention. Note that FIG. 4 illustrates the operation of the wireless LAN controller 10, one wireless LAN access point 21, another wireless LAN access point 22, another wireless LAN access point 23, and the wireless LAN station 30. ..

First, the operation before the timing t0 will be described.

FIG. 5 is a functional block diagram showing an operation before the timing t0 of the wireless LAN system according to the embodiment of the present invention.

First, the transmission instruction unit 13 of the wireless LAN controller 10 instructs one wireless LAN access point 21 to transmit a response request signal (for example, ARP Request or Null Data) (S10). One wireless LAN access point 21 receives a transmission instruction (S10) from the wireless LAN controller 10 by wired communication (S20). The transmission instruction (S10) and the instruction reception (S20) are almost simultaneous.

The transmission instruction (S10) includes the timing t0 (that is, the time point at which the response request signal is transmitted) designated by the timing designation unit 11.

After that, the reception standby instruction unit 15 of the wireless LAN controller 10 instructs the other wireless LAN access points 22 and 23 to wait for the reception of the response (S12). The other wireless LAN access points 22 and 23 receive the reception standby instruction (S12) from the wireless LAN controller 10 by wired communication (S30). The reception standby instruction (S12) and the instruction reception (S30) are almost simultaneous.

The reception standby instruction (S12) includes the timing t0 designated by the timing designation unit 11 (that is, the time when the standby start of receiving the response is started).

Eventually, time has passed and timing t0 has arrived.

FIG. 6 is a functional block diagram showing an operation at timing t0 of the wireless LAN system according to the embodiment of the present invention.

One wireless LAN access point 21 transmits a response request signal to the wireless LAN station 30 (S22). At the same time, the other wireless LAN access points 22 and 23 start waiting for the reception of the response (S32).

The response request signal is received by the wireless LAN station 30 after the timing t0.

FIG. 7 is a functional block diagram showing the operation of the wireless LAN system according to the embodiment of the present invention after the timing t0.

Upon receiving the response request signal, the wireless LAN station 30 transmits a response signal (for example, an ARP Reply or an Ack frame) (S40). The response signal is received by another wireless LAN access points 22 and 23 (S34). The other wireless LAN access point 22 is farther from the wireless LAN station 30 than the other wireless LAN access point 23, but since the propagation speed of the response signal is almost the optical speed, the other wireless LAN access point 22 The reception of the response by (S34) and the reception of the response by another wireless LAN access point 23 (S34) are almost simultaneous.

The other wireless LAN access points 22 and 23 each measure the received signal strength (RSSI) of the received (S34) response (S36). The measured received signal strength (RSSI) is transmitted to the wireless LAN controller 10 and received by the RSSI receiving unit 14 of the wireless LAN controller 10 (S14).

The received signal strength (RSSI) received by the RSSI receiving unit 14 (measured by another wireless LAN access points 22 and 23) is the received signal strength (RSSI) recorded by the RSSI recording unit 12 (one of them). It is compared with the one measured by the wireless LAN access point 21).

FIG. 8 is a functional block diagram showing an operation after the timing t0 of the wireless LAN system according to the embodiment of the present invention (however, after the comparison of received signal strengths).

The received signal strength (RSSI) received by the RSSI receiving unit 14 of the wireless LAN controller 10 (measured by another wireless LAN access points 22 and 23) and the received signal strength (RSSI) recorded by the RSSI recording unit 12. ) (Measured by one wireless LAN access point 21) is given to the RSSI comparison unit (wireless LAN access point detection unit) 16.

The RSSI comparison unit 16 compares the received signal strength (RSSI) received by the RSSI receiving unit 14 with the received signal strength (RSSI) recorded in the RSSI recording unit 12 (S16). Based on this comparison result, the RSSI comparison unit 16 further receives a response rather than the reception signal strength at the time of wireless communication at one wireless LAN access point 21 among the other wireless LAN access points 22 and 23. Detects a wireless LAN access point with strong signal strength. In the example of FIG. 1, the RSSI comparison unit 16 detects another wireless LAN access point 23. Then, the candidate selection unit 17 selects another wireless LAN access point 23.

The communication disconnection instruction unit 18 of the wireless LAN controller 10 receives another wireless LAN access point 23, which is a candidate selected from the candidate selection unit 17, and with respect to one wireless LAN access point 21, the wireless LAN station 30 and the wireless LAN station 30. Instructs to disconnect the communication (S18). One wireless LAN access point 21 disconnects wireless communication with the wireless LAN station 30 (S24).

After that, the wireless LAN station 30 establishes wireless communication with another nearest wireless LAN access point 23 by roaming.

However, the communication disconnection instruction unit 18 may transmit another wireless LAN access point 23, which is a candidate for establishing new wireless communication, to the wireless LAN station 30. In this case, the wireless LAN station 30 attempts wireless communication with another wireless LAN access point 23 and establishes wireless communication.

According to the embodiment of the present invention, it is possible to detect the wireless LAN access point 23 suitable for wireless communication with the wireless LAN station 30 so as not to interfere with the operation of the other wireless LAN access points 22 and 23 as much as possible. it can.

That is, the other wireless LAN access points 22 and 23 use the response channel (one wireless LAN access point 21 for transmission and reception) for a short time from the start of the reception standby (S32) to the reception of the response (S34). It suffices to make it possible to receive the signal of the channel). Other wireless LAN access points 22 and 23 cannot be used for normal operation (transmission and reception are performed on a channel "different" from the channel used by one wireless LAN access point 21 for transmission and reception). Is only this short time and does not hinder the operation.

It should be noted that the other wireless LAN access points 22 and 23 may start waiting for the reception of the response according to the time when the response request signal is transmitted from one wireless LAN access point 21 (for example, they start at the same time). If possible, the timing designation unit 11, the transmission instruction unit 13, and the reception standby instruction unit 15 may be omitted. For example, one wireless LAN access point 21 may determine the time point at which the response request signal is transmitted and notify the other wireless LAN access points 22 and 23. Alternatively, another wireless LAN access point 22 or 23 may determine the start time of waiting for the reception of the response and notify one wireless LAN access point 21.

Further, in the embodiment of the present invention, the waiting for receiving the response is started at the same time as t0 at the time of transmitting the response request signal, but it does not necessarily have to be at the same time. Waiting for the reception of the response may be started according to the time point t0 of the transmission of the response request signal.

For example, the standby for receiving the response is started after the time t0 of the transmission of the response request signal from one wireless LAN access point 21 and before the reception of the response by the other wireless LAN access points 22 and 23. You may try to do so.

Alternatively, the standby for receiving the response may be started shortly before the time t0 of the transmission of the response request signal from one wireless LAN access point 21. However, if it is too far before the timing t0, it interferes with the normal operation of the other wireless LAN access points 22 and 23, so the waiting for receiving the response should be started "a little" before the timing t0. ..

In the present embodiment, another wireless LAN access point 23 (closest to the wireless LAN station 30), one wireless LAN access point 21, and another wireless LAN access point 22 are arranged in the order of proximity to the wireless LAN station 30. It is supposed to be arranged. However, the positional relationship is not necessarily limited to this.

(1) When one wireless LAN access point 21 is the farthest For example, another wireless LAN access point 23 (closest to the wireless LAN station 30), another wireless LAN access point 22, in order of proximity to the wireless LAN station 30. There may be a case where a certain wireless LAN access point 21 is arranged. In such a case, the received signal strength of the response of not only another wireless LAN access point 23 but also another wireless LAN access point 22 is stronger than the received signal strength at the time of wireless communication at one wireless LAN access point 21. .. Therefore, the different wireless LAN access points 22 and 23 are the detection results by the RSSI comparison unit 16. The candidate selection unit 17 selects another wireless LAN access point 23 having the strongest response reception signal strength.

(2) When one wireless LAN access point 21 is the closest For example, one wireless LAN access point 21 (closest to the wireless LAN station 30) and another wireless LAN access point 23 in the order of proximity to the wireless LAN station 30. , Another wireless LAN access point 22 may be arranged. In such a case, the received signal strength of the response of the other wireless LAN access points 22 and 23 is weaker than the received signal strength at the time of wireless communication at one wireless LAN access point 21. Therefore, there is no detection result by the RSSI comparison unit 16. The candidate selection unit 17 does not select a candidate. If the candidate selection unit 17 does not select any candidate, the communication disconnection instruction unit 18 does not give an instruction to disconnect the communication.

Further, in the present embodiment, the candidate selection unit 17 selects the detection result by the RSSI comparison unit 16 having the strongest received signal strength of the response. However, the candidate selection unit 17 may select any one of the detection results by the RSSI comparison unit 16, and is not limited to the above selection method. For example, another wireless LAN access point with the strongest received signal strength may be selected except for another wireless LAN access point that is congested.

(1) When one wireless LAN access point 21 is the farthest, that is, another wireless LAN access point 23 (closest to the wireless LAN station 30) and another wireless LAN access point 22 in the order of proximity to the wireless LAN station 30. A method of selecting a further candidate by the candidate selection unit 17 will be described by taking as an example a case where a certain wireless LAN access point 21 is arranged.

Here, it is assumed that the other wireless LAN access point 23 is congested, while the other wireless LAN access point 22 is not congested. Then, the wireless LAN access point having the strongest reception signal strength except for the congested wireless LAN access point 23 is the wireless LAN access point 22, and the candidate selection unit 17 selects the wireless LAN access point 22.

However, whether or not it is congested may be determined by whether or not the number of wireless LAN stations connected to another wireless LAN access point exceeds a predetermined threshold value. Alternatively, even if it is determined whether or not (the traffic volume of another wireless LAN access point (bps)) / (the maximum traffic volume (bps) that another wireless LAN access point can communicate with) exceeds a predetermined threshold value. Good.

Further, the above embodiment can be realized as follows. A computer equipped with a CPU, a hard disk, and a media (floppy (registered trademark) disk, CD-ROM, etc.) reader is provided with the above parts, for example, the wireless LAN controller 10 or the wireless LAN access points 21, 22, and 23. Read the media on which the program to be realized is recorded and install it on the hard disk. The above function can also be realized by such a method.

10 Wireless LAN controller (wireless LAN device)
11 Timing specification unit t0 Timing 13 Transmission instruction unit 15 Reception standby instruction unit 12 RSSI recording unit 14 RSSI reception unit 16 RSSI comparison unit (wireless LAN access point detection unit)
17 Candidate selection unit 18 Communication disconnection instruction unit 21 One wireless LAN access point 22, 23 Another wireless LAN access point 30 Wireless LAN station (wireless LAN communication terminal)

Claims (9)

A wireless LAN access that transmits a response request signal requesting a response to a wireless LAN access point that is wirelessly communicating with the wireless LAN access point. Points and
Another wireless LAN access point that is different from the one wireless LAN access point and that starts waiting for reception of the response according to the time of transmission of the response request signal.
It is a wireless LAN device connected to
A means for giving a time point for transmitting the response request signal to the one wireless LAN access point, and
A means of giving the other wireless LAN access point a time point at which to start waiting for reception of the response.
Among the other wireless LAN access points, a wireless LAN access that detects a wireless LAN access point whose response reception signal strength is stronger than the reception signal strength at the time of the wireless communication at the one wireless LAN access point. Equipped with a point detector
Receives the received signal strength during the wireless communication from the one wireless LAN access point.
Receives the received signal strength of the response from the other wireless LAN access point.
Wireless LAN device. The wireless LAN device according to claim 1.
A transmission instruction unit that instructs the one wireless LAN access point to transmit the response request signal, and
A reception standby instruction unit that instructs the other wireless LAN access point to wait for reception of the response,
Wireless LAN device equipped with. The wireless LAN device according to claim 1.
The other wireless LAN access point is provided with a reception standby instruction unit for instructing reception of the response.
Waiting for the reception of the response starts at the same time as the transmission of the response request signal.
Wireless LAN device. The wireless LAN device according to claim 1.
The other wireless LAN access point is provided with a reception standby instruction unit for instructing reception of the response.
Waiting for the response to be received begins prior to the reception of the response by the other wireless LAN access point.
Wireless LAN device. The wireless LAN device according to claim 1.
The other wireless LAN access point is provided with a reception standby instruction unit for instructing reception of the response.
Waiting for the response to be received is to enable the other wireless LAN access point to receive the signal of the response channel.
Wireless LAN device. The wireless LAN device according to claim 1.
The one wireless LAN access point is provided with a transmission instruction unit for instructing the transmission of the response request signal.
The response request signal is ARP Request or Null Data.
Wireless LAN device. The wireless LAN device according to claim 1.
A wireless LAN device provided with a communication disconnection instruction unit that instructs one wireless LAN access point to disconnect communication with the wireless LAN communication terminal when there is a detection result of the wireless LAN access point detection unit. .. The wireless LAN device according to claim 1.
A wireless LAN device that transmits one of the detection results of the wireless LAN access point detection unit to the wireless LAN communication terminal. A wireless LAN access that transmits a response request signal requesting a response to a wireless LAN access point that is wirelessly communicating with the wireless LAN access point. Points and
Another wireless LAN access point that is different from the one wireless LAN access point and that starts waiting for reception of the response according to the time of transmission of the response request signal.
It is a communication processing method in a wireless LAN device connected to
A step of giving the time point of transmission of the response request signal to the one wireless LAN access point, and
A step of giving the other wireless LAN access point a time point at which the waiting for receiving the response starts is given.
The process of receiving the received signal strength during wireless communication from the one wireless LAN access point,
The step of receiving the received signal strength of the response from the other wireless LAN access point, and
Among the other wireless LAN access points, a wireless LAN access that detects a wireless LAN access point whose response reception signal strength is stronger than the reception signal strength at the time of the wireless communication at the one wireless LAN access point. Point detection process and
Communication processing method with.

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