WO2013094331A1

WO2013094331A1 - Communication device

Info

Publication number: WO2013094331A1
Application number: PCT/JP2012/079067
Authority: WO
Inventors: 柘植　数夫
Original assignee: 日本電気株式会社
Priority date: 2011-12-22
Filing date: 2012-11-09
Publication date: 2013-06-27
Also published as: JPWO2013094331A1

Abstract

A measurement unit (110) measures the strength of reception of radio waves from other communication devices. When the communication device is operating in client mode, a notification unit (160) sends a notification of the result of the measurement by the measurement unit (110) to an owner communication device, which is a communication device among the other communication devices that is operating in owner mode. When the communication device is operating in owner mode, a candidate determination unit (150) determines an owner candidate communication device from amongst the other communication devices on the basis of the notification of the measurement result sent from other communication devices, and the notification unit (160) sends a notification of the owner candidate communication device determined by the candidate determination unit (150) to other communication devices. When the communication device is operating in client mode, when communication with the owner communication device is no longer possible, a connection unit (140) establishes a connection with the owner candidate communication device for which a notification has been sent from the owner communication device.

Description

Communication device

The present invention relates to a communication device, a communication system, a communication method, and a program for performing communication, and more particularly to a communication device, a communication system, a communication method, and a program for performing wireless communication.

As an example of a form for performing general wireless communication, a form configured by a wireless access point connected to a wired network and a wireless client device connected to the wired network via the wireless access point (for example, a patent) Reference 1).

In such a form, one wireless network is configured by one wireless access point and a wireless client device existing in an area where wireless communication with the wireless access point is possible.

Also, as a similar form, there is an ad hoc wireless network such as Wi-Fi Direct. In this Wi-Fi Direct, one of the wireless communication devices participating in the network is a group owner having an access point function, and is directly connected to another wireless communication device (hereinafter referred to as a client). In addition, when a client communicates with another client, the client communicates via the group owner.

JP 2006-165623 A

However, in the above-described ad hoc network, when a group owner becomes unable to communicate due to a failure or the like, a client participating in the network cannot communicate with other clients. There is a problem.

An object of the present invention is to provide a communication device, a communication system, a communication method, and a program that solve the above-described problems.

The communication device of the present invention
A communication device having an owner mode that operates as an access point and a client mode that operates as a client, and performs wireless communication with other communication devices,
A measurement unit for measuring the reception intensity of the radio wave transmitted by the other communication device;
When operating in the client mode, a notification unit that notifies the owner communication device operating in the owner mode of the other communication devices, the measurement result of the measurement unit,
When operating in the client mode, when it becomes impossible to communicate with the owner communication device, a connection unit for connecting to the owner candidate communication device notified from the owner communication device,
When operating in the owner mode, when the measurement result is notified from the other communication device, candidate determination for determining the owner candidate communication device from the other communication devices based on the measurement result And
When the notification unit is operating in the owner mode, the notification unit notifies the other communication device of the owner candidate communication device determined by the candidate determination unit.

The communication system of the present invention
A communication system having an owner mode that operates as an access point and a client mode that operates as a client, and having a plurality of communication devices that perform wireless communication with other communication devices,
The communication device
A measurement unit for measuring the reception intensity of the radio wave transmitted by the other communication device;
When operating in the client mode, a notification unit that notifies the owner communication device operating in the owner mode of the other communication devices, the measurement result of the measurement unit,
When operating in the client mode, when it becomes impossible to communicate with the owner communication device, a connection unit for connecting to the owner candidate communication device notified from the owner communication device,
When operating in the owner mode, when the measurement result is notified from the other communication device, candidate determination for determining the owner candidate communication device from the other communication devices based on the measurement result And
When the notification unit is operating in the owner mode, the notification unit notifies the other communication device of the owner candidate communication device determined by the candidate determination unit.

Further, the communication method of the present invention includes:
A communication method in a communication system having an owner mode that operates as an access point and a client mode that operates as a client, and having a plurality of communication devices that perform wireless communication with other communication devices,
A process in which the communication device measures reception intensity of a radio wave transmitted by the other communication device;
A process in which the client communication device operating in the client mode of the communication devices notifies the measurement result to the owner communication device operating in the owner mode of the communication device;
The owner communication device determines an owner candidate communication device from the client communication device based on the measurement result notified from the client communication device;
The owner communication device notifies the client communication device of the determined owner candidate communication device;
When the client communication device becomes unable to communicate with the owner communication device, the client communication device performs a process of connecting to the owner candidate communication device notified from the owner communication device.

The program of the present invention is
A program for causing a communication device to perform wireless communication with another communication device, including an owner mode that operates as an access point and a client mode that operates as a client,
A procedure for measuring the reception intensity of radio waves transmitted by the other communication device;
When operating in the client mode, a procedure for notifying the measured result to the owner communication device operating in the owner mode among the other communication devices;
When operating in the owner mode, when the measurement result is notified from the other communication device, a procedure for determining an owner candidate communication device from the other communication devices based on the measurement result;
When operating in the owner mode, a procedure for notifying the determined other candidate communication device to the other communication device;
When operating in the client mode, when communication with the owner communication device becomes impossible, a procedure for connecting to the owner candidate communication device notified from the owner communication device is executed.

As described above, in the present invention, even when a group owner becomes unable to communicate, an optimum communication environment is established between other communication devices participating in the network to perform communication. be able to.

It is a figure which shows one Embodiment of the communication system of this invention. It is a figure which shows an example of an internal structure of the communication apparatus shown in FIG. It is a sequence diagram for demonstrating the communication method in the communication system shown in FIG. It is a figure which shows the connection form of the wireless network in which the Wi-Fi connection was established by making a communication apparatus into an owner communication apparatus. It is a figure which shows an example of the electromagnetic wave intensity | strength list | wrist which each communication apparatus produced. It is a figure which shows an example of a mode when communication becomes impossible between an owner communication apparatus and a client communication apparatus. It is a figure which shows an example of a mode when an owner candidate communication apparatus and a client communication apparatus are connected after communication becomes impossible between an owner communication apparatus and a client communication apparatus.

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

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

As shown in FIG. 1, the present embodiment is a wireless network 200 composed of a plurality of communication devices 100-1 to 100-4.

The communication devices 100-1 to 100-4 are communication devices having a wireless communication function. Communication apparatuses 100-1 to 100-4 each have an owner mode that operates as an access point and a client mode that operates as a client. These two operation modes will be described later. Note that the communication devices 100-1 to 100-4 may operate in either the owner mode or the client mode. In this case, however, the communication devices 100-1 to 100-4 periodically operate when operating in the client mode. Operates in owner mode. Further, the communication devices 100-1 to 100-4 may always operate at the same time in the owner mode and the client mode.

In the communication system shown in FIG. 1, a case where there are four communication devices is shown as an example, but three or five or more communication devices may be used.

FIG. 2 is a diagram illustrating an example of an internal configuration of the communication apparatus 100-1 illustrated in FIG. The internal configuration of communication apparatuses 100-2 to 100-4 shown in FIG. 1 is the same as the internal configuration of communication apparatus 100-1 shown in FIG.

As shown in FIG. 2, the communication device 100-1 shown in FIG. 1 includes a measurement unit 110, a reception unit 120, a storage unit 130, a connection unit 140, a candidate determination unit 150, and a notification unit 160. Is provided. FIG. 2 shows only the components related to the present invention among the components included in the communication device 100-1.

The measuring unit 110 measures the reception intensity of radio waves transmitted from the other communication devices 100-2 to 100-4. Although a specific measurement method is not particularly defined, for example, by measuring the S / N ratio, error rate, etc., and calculating the communication quality, the one with high communication quality is made strong in radio wave reception strength. Also good.

Also, the measurement unit measures the strength of radio waves transmitted by other communication devices 100-2 to 100-4 periodically operating in the owner mode.

The receiving unit 120 receives signals transmitted from the other communication devices 100-2 to 100-4. Specifically, the receiving unit 120 receives signals transmitted from the communication devices 100-2 to 100-4 when the communication device 100-1 operates in the owner mode. In addition, when communication device 100-1 operates in the client mode, reception unit 120 receives a signal transmitted from a communication device operating in owner mode (hereinafter referred to as an owner communication device). .

The storage unit 130 stores the reception intensity of the radio wave measured by the measurement unit 110 as a radio wave intensity list. Further, the storage unit 130 stores the radio wave intensity list transmitted from the communication devices 100-2 to 100-4 and received by the receiving unit 120 when the communication device 100-1 operates in the owner mode. Store every 100-4.

When the communication device 100-1 is operating in the client mode, the connection unit 140 connects to the owner candidate communication device that has already been notified from the owner communication device when communication with the owner communication device becomes impossible. Here, the connection unit 140 does not particularly define a method for determining whether or not the communication device 100-1 can no longer communicate with the owner communication device. For example, when the owner communication device periodically transmits a predetermined signal to a communication device (hereinafter referred to as a client communication device) operating in the client mode, and the receiving unit 120 does not receive the signal, It may be determined that communication with the owner communication device is no longer possible. Further, the information on the owner candidate communication device already notified from the owner communication device is received by the receiving unit 120 and stored in the storage unit 130.

When communication device 100-1 is operating in the owner mode, candidate determination unit 150, when notified of the measurement results of the radio wave reception intensity from communication devices 100-2 to 100-4, based on the measurement results Then, an owner candidate communication device to be the next owner communication device is determined from among the communication devices 100-2 to 100-4. Here, the measurement result of the radio wave reception intensity notified from the communication devices 100-2 to 100-4 is stored in the storage unit 130. Then, candidate determination unit 150 reads out the measurement result of the radio wave reception intensity notified from communication devices 100-2 to 100-4 stored in storage unit 130, and determines an owner candidate communication device.

This owner candidate communication device determination method will be described later.

When the communication device 100-1 is operating in the client mode, the notification unit 160 notifies the owner communication device of the result measured by the measurement unit 110. Here, since the measurement result is stored in the storage unit 130 as a radio wave intensity list, the notification unit 160 reads out the radio wave intensity list from the storage unit 130 and notifies (transmits) it to the owner communication device.

In addition, when the communication device 100-1 operates in the owner mode, the notification unit 160 notifies the communication device 100-2 to 100-4 of the owner candidate communication device determined by the candidate determination unit 150.

In addition, when the notification unit 160 operates in the client mode, the notification unit 160 also periodically operates as the owner mode to transmit radio waves.

Hereinafter, a communication method in the communication system shown in FIG. 1 will be described. Here, a case will be described as an example where the communication device 100-1 is initially set as the owner communication device. Note that any method may be used for determining which communication device is the owner communication device first.

FIG. 3 is a sequence diagram for explaining a communication method in the communication system shown in FIG.

First, in step 1, the communication devices 100-2 to 100-4 as client communication devices establish a Wi-Fi connection with the communication device 100-1 as an owner communication device.

FIG. 4 is a diagram showing a connection form of the wireless network 200 in which Wi-Fi connection is established with the communication device 100-1 as the owner communication device.

As shown in FIG. 4, the connection between the communication device 100-1 as the owner communication device and the communication devices 100-2 to 100-4 is established. In FIG. 4, the communication device 100-1 and the communication devices 100-2 to 100-4 are connected by a solid line to show the connection, but this connection is not a wired connection but a wireless connection.

Thereafter, in step 2, each measurement unit 110 of each of communication devices 100-1 to 100-4 measures the reception intensity of radio waves transmitted from other communication devices, and creates a list of measurement results (radio wave intensity list). And stored in the storage unit 130. Radio waves are transmitted from the communication devices 100-1 to 100-4 when they are periodically operated in the owner mode. The radio wave includes SSID (Service Set Identifier) used in the wireless network 200 and MAC (Media Access Control) address assigned to each of the communication devices 100-1 to 100-4. The source of the transmitted radio wave can be identified.

FIG. 5 is a diagram showing an example of a radio wave intensity list created by each of the communication devices 100-1 to 100-4.

As shown in FIG. 5, each of the communication devices 100-1 to 100-4 has a radio wave intensity list created from the results measured by the measurement unit 110.

Referring to the radio wave intensity list created by communication apparatus 100-1, the measurement result of the reception intensity of the radio wave transmitted from communication apparatus 100-2 is “90”, and the reception of the radio wave transmitted from communication apparatus 100-3 is received. The measurement result of the strength is “70”, the measurement result of the reception strength of the radio wave transmitted from the communication device 100-4 is “60”, and the priority (priority) is given from the higher measurement result. ing. That is, the priority is in the order of the communication device 100-2, the communication device 100-3, and the communication device 100-4.

Further, referring to the radio wave intensity list created by the communication apparatus 100-2, the measurement result of the reception intensity of the radio wave transmitted from the communication apparatus 100-1 is “90”, and the radio wave intensity transmitted from the communication apparatus 100-3. The measurement result of the received signal strength is “40”, the measurement result of the received signal strength of the radio wave transmitted from the communication device 100-4 is “30”, and the priority (priority) is higher from the higher measurement result. Has been granted. That is, the priority is in the order of the communication device 100-1, the communication device 100-3, and the communication device 100-4.

Further, referring to the radio wave intensity list created by the communication apparatus 100-3, the measurement result of the reception intensity of the radio wave transmitted from the communication apparatus 100-1 is “70”, and the radio wave intensity transmitted from the communication apparatus 100-2. The measurement result of the received signal strength is “40”, the measurement result of the received signal strength of the radio wave transmitted from the communication device 100-4 is “50”, and the priority (priority) is higher from the higher measurement result. Has been granted. That is, the priority is in the order of the communication device 100-1, the communication device 100-4, and the communication device 100-2.

Further, referring to the radio wave intensity list created by the communication device 100-4, the measurement result of the reception intensity of the radio wave transmitted from the communication device 100-1 is “60”, and the radio wave transmitted from the communication device 100-2. The measurement result of the received signal strength is “30”, the measurement result of the received signal strength of the radio wave transmitted from the communication device 100-3 is “50”, and the priority (priority) is higher from the higher measurement result. Has been granted. That is, the priority is in the order of the communication device 100-1, the communication device 100-3, and the communication device 100-2.

In addition, in FIG. 5, the numerical value of the radio wave reception intensity shown in each list is shown in the explanation of the radio wave intensity list so that the mutual strength relationship can be easily understood. Is different.

Subsequently, in step 3, the communication apparatuses 100-2 to 100-4 as client communication apparatuses transmit the radio wave intensity list from the notification unit 160 to the communication apparatus 100-1, thereby measuring the received radio wave intensity. To the communication device 100-1.

Then, the communication device 100-1 that has received the radio wave intensity list stores the received radio wave intensity list in the storage unit 130. In step 4, candidate determination unit 150 of communication device 100-1 determines an owner candidate communication device based on the radio wave intensity list.

This determination method has the highest priority in the radio wave intensity lists of the communication apparatuses 100-2 to 100-4 except for the radio wave reception intensity from the communication apparatus 100-1 that is the owner communication apparatus (reception of radio waves). The one with the highest intensity) is extracted from each radio wave intensity list, and the communication device with the largest number is determined as the owner candidate communication device.

The specific determination method will be described by taking as an example the case where the radio wave intensity lists created by the communication devices 100-2 to 100-4 are those shown in FIG.

Of the list of radio wave strengths created by the communication device 100-2, the one with the highest priority (highest radio wave strength) excluding the reception strength of radio waves from the communication device 100-1 is the communication device 100-3. . Of the radio wave intensity lists created by the communication device 100-3, the one with the highest priority (highest radio wave intensity) excluding the radio wave reception strength from the communication device 100-1 is the communication device 100-4. It is. Of the radio wave intensity lists created by the communication apparatus 100-4, the one with the highest priority (highest radio wave intensity) excluding the radio wave reception intensity from the communication apparatus 100-1 is the communication apparatus 100-3. It is. Therefore, since the number of communication devices 100-3 is 2 and the number of communication devices 100-4 is 1, the candidate determining unit 150 determines the communication device 100-3 as an owner candidate communication device.

Further, in the radio wave intensity list of each of the communication apparatuses 100-2 to 100-4, the communication having the highest average radio wave reception intensity except for the radio wave reception intensity from the communication apparatus 100-1 as the owner communication apparatus. The device may be determined as an owner candidate communication device.

In the example shown in FIG. 5, the average value of the reception intensity of the radio wave transmitted by the communication device 100-2 is
(40 + 30) ÷ 2 = 35
The average value of the reception intensity of the radio wave transmitted by the communication device 100-3 is
(40 + 50) ÷ 2 = 45
The average value of the reception intensity of the radio wave transmitted by the communication device 100-4 is
(30 + 50) ÷ 2 = 40
The communication device 100-3 has the highest average value. Therefore, candidate determination unit 150 determines communication device 100-3 as an owner candidate communication device.

When the owner candidate communication device is determined, in step 5, the notification unit 160 of the communication device 100-1 notifies the determined owner candidate communication device to the communication devices 100-2 to 100-4. Specifically, the notification unit 160 transmits to the communication devices 100-2 to 100-4, as owner candidate information, a signal indicating that the owner candidate communication device to be the next owner communication device is the communication device 100-3.

The communication devices 100-2 to 100-4 store the owner candidate information transmitted from the communication device 100-1 in the storage unit 130.

Note that the processing in steps 2 to 5 may be periodically repeated, or may be performed at a predetermined timing.

Thereafter, when communication with the communication device 100-1 is interrupted, in step 6, the connection unit 140 of the communication devices 100-2 and 100-4 stores the communication device stored as the owner candidate communication device. A Wi-Fi connection is established with 100-3.

FIG. 6 is a diagram illustrating an example of a state where communication between the owner communication device and the client communication device becomes impossible.

FIG. 7 is a diagram illustrating an example of a state when the owner candidate communication device and the client communication device are connected after communication between the owner communication device and the client communication device is disabled.

As shown in FIG. 6, when communication is not possible between the communication device 100-1 that is the owner communication device and the communication devices 100-2 to 100-4 that are the client communication devices, the process of step 6 is performed. As shown in FIG. 7, a communication device 100-3 that is an owner candidate communication device and communication devices 100-2 and 100-4 that are client communication devices are connected.

Then, the processing of steps 2 to 5 is performed in the communication devices 100-2 to 100-4.

As described above, after the communication between the owner communication device and the client communication device becomes impossible, the connection between the owner candidate communication device and the client communication device is not established, but the owner communication device and the client A connection between the owner candidate communication device and the client communication device may be established in the background while communication with the communication device is possible. In this case, there is no time loss when re-establishing the connection, and smoother network switching can be performed when communication with the owner communication device is not possible. Furthermore, the communication interruption period can be shortened.

In this way, even if the group owner becomes unable to communicate, other communication devices are used to determine the new group owner from other communication devices participating in the network and perform communication. Communication between devices can be continued. Furthermore, since the new group owner is determined based on the radio wave reception intensity, the optimum group owner can be determined.

The processing performed by each component provided in each of the communication devices 100-1 to 100-4 may be performed by a logic circuit that is produced according to the purpose. In addition, a computer program (hereinafter referred to as a program) in which processing contents are described as a procedure is recorded on a recording medium readable by each of the communication devices 100-1 to 100-4, and the program recorded on the recording medium is communicated. The devices 100-1 to 100-4 may be read and executed. The recording media readable by each of the communication devices 100-1 to 100-4 include transferable recording media such as a floppy (registered trademark) disk, a magneto-optical disk, a DVD, and a CD, as well as the communication devices 100-1 to 100-4. Reference numeral 100-4 indicates a memory such as a ROM and a RAM, an HDD, and the like built in each. The program recorded on the recording medium is read by a CPU (not shown) provided in each of the communication devices 100-1 to 100-4, and the same processing as described above is performed under the control of the CPU. Here, the CPU operates as a computer that executes a program read from a recording medium on which the program is recorded.

As mentioned above, although this invention was demonstrated with reference to embodiment, this invention is not limited to the said embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2011-281355 filed on Dec. 22, 2011, the entire disclosure of which is incorporated herein.

Claims

A communication device having an owner mode that operates as an access point and a client mode that operates as a client, and performs wireless communication with other communication devices,
A measurement unit for measuring the reception intensity of the radio wave transmitted by the other communication device;
When operating in the client mode, a notification unit that notifies the owner communication device operating in the owner mode of the other communication devices, the measurement result of the measurement unit,
When operating in the client mode, when it becomes impossible to communicate with the owner communication device, a connection unit for connecting to the owner candidate communication device notified from the owner communication device,
When operating in the owner mode, when the measurement result is notified from the other communication device, candidate determination for determining the owner candidate communication device from the other communication devices based on the measurement result And
When the notification unit is operating in the owner mode, the notification unit notifies the other communication device of the owner candidate communication device determined by the candidate determination unit.
The communication device according to claim 1,
When operating in the client mode, also periodically operates as the owner mode,
The notification unit emits radio waves when operating as the owner mode,
The communication device is characterized in that the measurement unit measures the intensity of a radio wave transmitted by the other communication device operating in the owner mode.
The communication device according to claim 1 or 2,
The candidate determination unit is the communication device having the highest number of communication devices having the highest radio wave reception intensity, excluding the radio wave reception strength from the owner communication device, among the measurement results notified from the other communication devices. Is determined as the owner candidate communication device.
The communication device according to claim 1 or 2,
The candidate determination unit determines a communication device having the highest average radio wave reception intensity from the measurement results notified from the other communication device, except for the radio wave reception intensity from the owner communication device. A communication apparatus characterized by being determined as a communication apparatus.
The communication device according to any one of claims 1 to 4,
The communication unit establishes a connection to an owner candidate communication device notified from the owner communication device while communicating with the owner communication device.
A communication system having a plurality of communication devices according to any one of claims 1 to 5.
A communication method in a communication system having an owner mode that operates as an access point and a client mode that operates as a client, and having a plurality of communication devices that perform wireless communication with other communication devices,
A process in which the communication device measures reception intensity of a radio wave transmitted by the other communication device;
A process in which the client communication device operating in the client mode of the communication devices notifies the measurement result to the owner communication device operating in the owner mode of the communication device;
The owner communication device determines an owner candidate communication device from the client communication device based on the measurement result notified from the client communication device;
The owner communication device notifies the client communication device of the determined owner candidate communication device;
A communication method for performing processing of connecting to an owner candidate communication device notified from the owner communication device when the client communication device becomes unable to communicate with the owner communication device.
A communication device that has an owner mode that operates as an access point and a client mode that operates as a client, and performs wireless communication with other communication devices.
A procedure for measuring the reception intensity of radio waves transmitted by the other communication device;
When operating in the client mode, a procedure for notifying the measured result to the owner communication device operating in the owner mode among the other communication devices;
When operating in the owner mode, when the measurement result is notified from the other communication device, a procedure for determining an owner candidate communication device from the other communication devices based on the measurement result;
When operating in the owner mode, a procedure for notifying the determined other candidate communication device to the other communication device;
A program for executing a procedure of connecting to an owner candidate communication device notified from the owner communication device when communication with the owner communication device becomes impossible when operating in the client mode.