JP2016012817A - Radio communication device and radio communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication device capable of determining a time and a channel by which effective transmission and reception of data can be performed.SOLUTION: A radio communication device (10) comprises: a radio communication unit (Wi-Fi communication unit 110) configured to be able to communicate data with an external apparatus (information processing device 20) by radio communication selectively using any of a plurality of channels; a radio environment observation unit (120) configured to be able to observe time variation in a surrounding radio environment; and a radio communication environment determination unit (130) configured to be able to determine a time and a channel when and where interference by other radio communication is little on the basis of an observation result by the radio environment observation unit.

Description

  One embodiment of the present invention relates to a wireless communication device or the like capable of transmitting and receiving data by wireless communication.

  In recent years, wireless communication devices capable of transmitting and receiving data by wireless communication have been widely distributed. In such a wireless communication device, the amount of data that can be transmitted and received by wireless communication changes due to mutual radio wave interference between the wireless communication devices. On the other hand, conventionally, data backup using wired communication such as a LAN is performed by a PC (Personal Computer) or a server device. Such data backup is scheduled and periodically executed at a time such as midnight when the LAN line is relatively rarely used, so that the user does not affect the use of the LAN line for purposes other than backup. In addition, data backup was possible in a short time. Such scheduled and periodic data backup is also called scheduling backup. By the way, Patent Document 1 discloses a technique for selecting a channel with as little interference as possible when performing wireless communication. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique that allows communication bands to be interchanged in an environment where connection communication between wireless communication access points is possible. Patent Document 3 discloses a technique for monitoring interference due to other channels in wireless communication.

JP 2010-233187 A JP 2010-206577 A JP 2013-168904 A

  However, in the above-described conventional technology, it has not been possible to determine the time and channel at which data can be efficiently transmitted and received in a wireless communication environment. Further, in such a wireless communication environment, a method for effectively backing up data such as a PC or a server device has not been sufficiently studied.

  The present invention adopts the following means in order to solve the above problems. In the following description, in order to facilitate understanding of the invention, reference numerals and the like in the drawings are appended in parentheses, but each component of the present invention is not limited to these appendices. It should be construed broadly to the extent that contractors can technically understand.

Means 1 of the present invention include
A wireless communication unit (Wi-Fi communication unit 110) configured to be able to transmit and receive data by wireless communication with an external device (information processing apparatus 20) selectively using any of a plurality of channels;
A wireless environment observation unit (120) configured to be capable of observing temporal changes in the surrounding wireless environment;
A wireless communication environment determination unit (130) configured to be able to determine a time and a channel with less interference due to other wireless communication based on the observation result of the wireless environment observation unit. (10).

  According to the wireless communication device (10) having the above configuration, it is possible to determine a time and a channel in which data can be efficiently transmitted and received with less interference from other wireless communication in the vicinity.

Means 2 of the present invention
A data storage device (storage device 30) configured to receive data from an external device (information processing device 20) according to the time and channel determined by the wireless communication environment determination unit (130) and store the data. The wireless communication device (10) of the means 1 further comprises a data transmission / reception control unit (CPU 100) configured to be controllable to transmit the received data.

  According to the wireless communication device (10) having the above-described configuration, the data storage device (storage device 30) is connected to the external device (information processing) using the determined time and channel capable of efficiently transmitting and receiving data. Data received from the device 20) can be transmitted. As a result, it is possible to efficiently back up the data of the external device (information processing apparatus 20).

Means 3 of the present invention
The wireless environment observation unit (120) observes a time change of a surrounding wireless environment by acquiring a wireless beacon (Beacon) emitted by another wireless communication device. A communication device (10).

  According to the wireless communication apparatus (10) having the above-described configuration, it is possible to observe a time change of the surrounding wireless environment using a wireless sign (Beacon) widely used in wireless communication devices.

The means 4 of the present invention
The wireless environment observing unit (120) transmits and receives data by wireless communication with an external device (information processing apparatus 20) to acquire an interference occurrence state, thereby observing time changes in the surrounding wireless environment. The wireless communication device (10) of the means 1 or 2 is characterized.

  According to the wireless communication device (10) having the above-described configuration, it is possible to observe time changes in the surrounding wireless environment by actually performing wireless communication with the external device (information processing device 20).

The means 5 of the present invention
The wireless environment observation unit (120) observes a time change of the surrounding wireless environment by acquiring a packet amount in the surrounding wireless environment. The wireless communication device (10) of the means 1 or 2 It is.

  According to the wireless communication device (10) having the above configuration, it is possible to observe the time change of the surrounding wireless environment by using the packet capture function.

The means 6 of the present invention
A wireless communication method that is executed by a wireless communication device capable of transmitting and receiving data by wireless communication with an external device by selectively using one of a plurality of channels,
A first step (S620) of observing a time change of the surrounding wireless environment;
A second step (S620) for determining a time and channel with less interference due to other wireless communication based on the observation result in the first step;
A third step (S670) of receiving data from an external device according to the time and channel determined in the second step, and transmitting the received data to a data storage device configured to store the data; A wireless communication method characterized by including the wireless communication method.

  According to the wireless communication method having the above configuration, the data storage device (storage device 30) is connected to the external device (information processing device 20) using the determined time and channel at which data can be efficiently transmitted and received. Data received from can be transmitted. As a result, it is possible to efficiently back up the data of the external device (information processing apparatus 20).

The figure which shows the structural example of a radio | wireless communications system. The flowchart which shows a data backup process. The figure which shows the specific example of the time change of the communication for every access point. The figure which shows the specific example of the radio | wireless environment around 8:00. The figure which shows the specific example of the surrounding wireless environment at 22:00.

An embodiment according to the present invention will be specifically described according to the following configuration with reference to the drawings. However, the embodiment described below is merely an example of the present invention and does not limit the technical scope of the present invention. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and the description may be abbreviate | omitted.
1. Embodiment 1
(1) Configuration example of wireless communication system (2) Specific example of data backup processing Embodiment 2
3. Embodiment 3
4). Supplementary items 5. Features of the present invention

<1. Embodiment 1>
First, Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 5.

  The wireless communication system of this embodiment is characterized by a method in which an information processing device such as a PC (Present Computer) or a server device backs up data to a storage device such as an HDD using a wireless communication device such as a wireless router. Have.

<(1) Configuration example of wireless communication system>
FIG. 1 is a diagram illustrating a configuration example of a wireless communication system according to the present embodiment. The wireless communication system includes a wireless communication device 10, an information processing device 20, and a storage device 30. The wireless communication device 10 is connected to the information processing device 20 wirelessly. The wireless communication device 10 is connected to the storage device 30 by wire.

<Wireless communication apparatus 10>
The wireless communication device 10 is a device that can transmit and receive data by wireless communication, such as a wireless router, and includes a CPU 100, a Wi-Fi communication unit 110, a wireless environment observation unit 120, a wireless communication environment determination unit 130, and an interface unit 140. It is comprised including. These CPU 100, Wi-Fi communication unit 110, wireless environment observation unit 120, wireless communication environment determination unit 130, and interface unit 140 are configured to be able to execute transmission / reception of signals with each other via a bus 160.

<CPU 100>
The CPU 100 is a central processing unit configured to be able to execute various processes in the wireless communication device 10, and includes a Wi-Fi communication unit 110, a wireless environment observation unit 120, a wireless communication environment determination unit 130, and an interface unit 140. It is configured to be controllable via the bus 160. Further, the CPU 100 is configured to be controllable to transmit data received from an external device such as the information processing apparatus 20 to the storage apparatus 30 via the interface unit 140.

<Wi-Fi communication unit 110>
The Wi-Fi communication unit 110 is configured to be able to execute data transmission / reception by wireless communication by selectively using any of a plurality of (for example, 13) channels with an external device including the information processing apparatus 20. Is done. The Wi-Fi communication unit 110 is configured to be able to determine and change a channel used for wireless communication under the control of the wireless communication environment determination unit 130 or the CPU 100.

<Wireless Environment Observation Unit 120>
The wireless environment observation unit 120 is configured to be able to continuously or intermittently observe the wireless environment around the wireless communication device 10 and store the observation results. For example, the wireless environment observation unit 120 periodically acquires a beacon issued by another wireless communication device as a surrounding wireless environment (for example, every 10 minutes), and (1) a channel band of another wireless communication , (2) Link speed of other wireless communication, and (3) Signal strength of other wireless communication can be observed.

<Wireless Communication Environment Determination Unit 130>
The wireless communication environment determination unit 130 determines a time and channel with less interference due to other wireless communication based on the observation result of the wireless environment observation unit 120 for a certain time or more (for example, 48 hours or more). That is, based on the observed radio beacon, the radio observation unit regularly observes the channel used for other radio communication and the radio wave intensity of this radio communication, for example, in 24 hours, which time Determine which channels have relatively little interference. A specific example of this determination will be described later.

<Interface unit 140>
The interface unit 140 is configured to be able to execute data transmission / reception with the storage apparatus 30 connected to the outside of the wireless communication apparatus 10 by wire. For the connection between the wireless communication device 10 and the storage device 30, various wired connection methods such as USB or wired LAN can be adopted. The wireless communication device 10 and the storage device 30 may be connected by a wireless LAN or other wireless connection method. The interface unit 140 is configured to be able to transmit data received from the information processing apparatus 20 to the storage apparatus 30 under the control of the CPU 100.

<Bus 160>
The bus 160 is connected to each element included in the wireless communication device 10, and each of these elements is used to execute transmission / reception of data with each other.

<Information processing apparatus 20>
The information processing apparatus 20 includes a CPU 200, a Wi-Fi communication unit 210, a display unit 220, and an operation input unit 230. The CPU 200, Wi-Fi communication unit 210, display unit 220, and operation input unit 230 are configured to be able to execute transmission / reception of signals with each other via a bus 260.

<CPU 200>
The CPU 200 is a central processing unit configured to execute various processes in the information processing apparatus 20, and can control the Wi-Fi communication unit 210, the display unit 220, and the operation input unit 230 via the bus 260. Composed. Further, the CPU 200 is configured to be controllable to transmit data to be backed up to the wireless communication apparatus 10 and information related to the size of the data.

<Wi-Fi communication unit 210>
The Wi-Fi communication unit 210 is configured to be able to execute transmission / reception of data with the wireless communication apparatus 10 by wireless communication using any channel. The Wi-Fi communication unit 210 is configured to be able to determine and change a channel used for wireless communication through communication with the wireless communication device 10.

<Display unit 220>
The display unit 220 is configured by an LCD (Liquid Crystal Display), an organic EL display, or the like, and configured to be able to display the execution result of the software executed by the CPU 200 in a state that the user can visually recognize.

<Operation input unit 230>
The operation input unit 230 is connected to a keyboard or a mouse that can be input by the user, detects an operation input by the user, and is configured to output the detected operation input to the CPU 200.

<Storage device 30>
The storage device 30 is an information storage device such as an HDD, and is configured to store data. In particular, in the present embodiment, the storage apparatus 30 is used for backing up data of the information processing apparatus 20.

<(2) Specific example of data backup processing>
Next, a specific example of data backup processing executed by the information processing apparatus 20 and the wireless communication apparatus 10 will be described. FIG. 2 is a flowchart showing a specific example of this data backup processing.

<S500 to S510>
First, when the data backup process is started in the information processing apparatus 20 (S500), the information processing apparatus 20 confirms the size of data to be backed up under the control of the CPU 200, and determines the confirmed data size as Wi-. It transmits with respect to the radio | wireless communication apparatus 10 via the Fi communication part 210 (S510).

<S610>
The Wi-Fi communication unit 110 of the wireless communication device 10 that has received the data size of the data to be backed up from the information processing device 20 outputs this data size to the CPU 100 (S610). The CPU 100 estimates the time required for data backup based on the input data size.

<S620>
Next, under the control of the CPU 100, the wireless communication environment determination unit 130 determines the backup execution time and the channel used for the backup from the time change information of the wireless environment observed in advance by the wireless environment observation unit 120. (S620).

  Here, a specific example of the backup time and channel determination method performed by the wireless environment observation unit 120 and the wireless communication environment determination unit 130 will be described with reference to FIGS.

  FIG. 3 is a diagram illustrating a time change of wireless communication for each access point. FIG. 3 shows which channel (CH) is used for wireless communication by each access point (AP1 to AP6) in which time zone. For example, AP2 (access point 2) is performing wireless communication using CH1 (channel 1) approximately between about 9:00 and 18:00. At the time of 8 o'clock indicated by time T1, all of AP1 to AP6 are performing wireless communication using any one of the channels. Further, at 22:00 indicated by time T2, AP1, AP2, AP3, and AP5 are performing wireless communication, while AP4 and AP6 are not performing wireless communication.

  FIG. 4 is a diagram illustrating a wireless environment around the wireless communication device 10 at 8:00 indicated by the time T1. FIG. 5 is a diagram illustrating a wireless environment around the wireless communication device 10 at 22:00 indicated by time T2. 4 and 5, the horizontal axis indicates the channel, and the vertical axis indicates the radio wave intensity. Wireless communication using a certain channel also affects a channel adjacent to the channel to be used. Here, it is assumed that wireless communication affects (interfers with) communication in five channels centering on the channel being used. In addition, each radio communication has a radio field intensity, and a radio communication having a higher radio field intensity interferes with (or tends to affect) other radio communications.

  As shown in FIG. 4, at 8 o'clock, wireless communication is being performed on all channels. For example, in the vicinity of the channel 9, it can be seen that interference due to wireless communication with a strong radio field intensity of 2 occurs. Alternatively, it can be seen that interference due to other wireless communication is relatively reduced in the vicinity of the channel 4.

  On the other hand, as shown in FIG. 5, at 22:00, the wireless environment by other wireless communication shown in the actual battle is observed. That is, it can be seen that channel 7 and channel 8 do not cause interference due to other wireless communication. Therefore, for example, as indicated by a dotted line, even if the wireless communication device 10 and the information processing device 20 transmit and receive data by wireless communication using the channel 6, interference by other wireless communication is considerably small. It turns out that it becomes.

  The wireless communication environment determination unit 130 determines a time and a channel suitable for data backup based on the observation result by the wireless environment observation unit 120 as described above. For example, when the time change of the wireless environment as shown in FIGS. 3 to 5 is observed as described above and the time required for backup is about 1 hour, the wireless communication environment determining unit 130 performs the operation from 22:00 to 23 In the meantime, it is decided to use channel 6 to back up data.

<S630>
Next, the wireless communication environment determination unit 130 outputs the determined backup execution time and the channel used for backup execution to the CPU 100. The CPU 100 transmits the backup execution time and the channel used for backup execution to the information processing apparatus 20 via the Wi-Fi communication unit 110 (S630).

<S520>
The Wi-Fi communication unit 210 of the information processing apparatus 20 that has received the data backup execution time and the channel used for backup execution from the wireless communication apparatus 10 outputs this information to the CPU 200. The CPU 200 stores the execution time of these backups and the channel used for executing the backup. In the present embodiment, the start of the backup process in the information processing apparatus 20 starts as a result of receiving information from the wireless communication apparatus 10 as described below. However, the information processing apparatus 20 starts the backup process. It may be.

<S640-S660>
Next, in the wireless communication apparatus 10, the CPU 100 confirms whether or not the backup time has come (S640). When the backup time is reached (Y in S640), the wireless environment monitoring unit 120 confirms the surrounding wireless environment at this time, and uses the scheduled channel while avoiding interference due to other wireless communication. It is confirmed whether or not wireless data transmission / reception can be executed (S650). That is, in the above example, the wireless environment observation unit 120 confirms whether other wireless communication with strong radio field intensity is not observed in a channel near channel 6 at 22:00, for example. Here, if a channel that was scheduled and other wireless communication with strong radio field intensity is observed in the vicinity of the channel, the wireless communication environment determination unit 130 determines that the channel is estimated to have the least interference at this time. It is determined to transmit / receive data wirelessly using S (S660).

<S670>
Next, the CPU 100 of the wireless communication device 10 sends information about the start of backup and information on the used channel determined by the wireless communication environment determination unit 130 as described above via the Wi-Fi communication unit 110. Transmit to the processing device 20.

<S530 to S550>
In the information processing apparatus 20 that has received the information from the wireless communication apparatus 10 (S530), under the control of the CPU 200, transmission of backup data to the wireless communication apparatus 10 is started by wireless communication using the specified channel. (S540). When the transmission of the data to be backed up is completed (S550), the backup process in the information processing apparatus 20 ends (S550).

<S680>
The wireless communication device 10 that has received the data to be backed up from the information processing device 20 through the above processing transmits the received data to the storage device 30 via the interface unit 140. The storage device 30 that has received the data stores this data.

<S690>
When all the data transmitted from the information processing device 20 is stored in the storage device 30, the backup process in the wireless communication device 10 ends (S690).

  With the above processing, the data backup processing of the information processing apparatus 20 in the wireless communication system is performed.

<2. Second Embodiment>
Next, Embodiment 2 of the present invention will be described. In the present embodiment, the configuration of the wireless communication system and the data backup processing are the same as in the first embodiment, but the information used for observation of the wireless environment is different. For this reason, the processing of the wireless environment observation unit 120 is different from that of the first embodiment. Hereinafter, only the difference will be described, and the description of the same points as in the first embodiment will be omitted.

<Wireless Environment Observation Unit 120>
The wireless environment observation unit 120 is configured to be able to continuously or intermittently observe the wireless environment around the wireless communication device 10 and store the observation results. The wireless environment observation unit 120 of the present embodiment actually transmits and receives data to and from the information processing apparatus 20 using the Wi-Fi communication unit 110 to observe the surrounding wireless environment, and interferes with other wireless communication. Observe the occurrence of. Data transmission / reception for observation of the wireless environment is performed periodically (for example, every 10 minutes) several times. At this time, the wireless environment observation unit 120 observes the carrier wave detection before the start of wireless communication, the number of occurrences of collision avoidance, the transmission retry status at the time of data transfer, and the error correction after the data transfer. Based on these observation results, the wireless environment observation unit 120 determines what kind of interference occurs during data transfer. Based on the determination of the degree of interference by the wireless environment observation unit 120, the wireless communication environment determination unit 130 determines a time and channel with less interference due to other wireless communication.

<3. Embodiment 3>
Next, a third embodiment of the present invention will be described. In the present embodiment, the configuration of the wireless communication system and the data backup process are the same as in the first or second embodiment, but the information used for observation of the wireless environment is different. For this reason, the processing of the wireless environment observation unit 120 is different from both the first and second embodiments. Hereinafter, only the difference will be described, and the description of the same points as in the first and second embodiments will be omitted.

<Wireless Environment Observation Unit 120>
The wireless environment observation unit 120 is configured to be able to continuously or intermittently observe the wireless environment around the wireless communication device 10 and store the observation results. The wireless environment observation unit 120 of the present embodiment uses a packet capture function to observe the surrounding wireless environment, and periodically (for example, every 10 minutes) the amount of packets actually transmitted and received by other wireless communication. Observe. In this way, by monitoring the actual amount of packets, it becomes possible to distinguish between interference in a wireless LAN network and interference from other systems (such as those caused by microwave ovens or other wireless devices). The wireless environment can be categorized more specifically. This makes it possible to determine the radio environment more accurately.

<4. Supplementary items>
The specific description of the embodiment of the present invention has been given above. The above description is merely an embodiment, and the scope of the present invention is not limited to this embodiment, but should be broadly interpreted to the extent that a person skilled in the art can grasp.

  In the above embodiment, the storage apparatus 30 is connected to the wireless communication apparatus 10 via the interface unit 140. However, as described above, the storage apparatus 30 is not limited to such a form. The storage device 30 may be connected to the wireless communication device 10 via, for example, a network (including a so-called cloud form). The wireless communication device 10 may be configured to include the storage device 30.

  Further, data backup is not necessarily performed at a time, and may be performed in several times within 24 hours.

<5. Features of the present invention>
The wireless communication device 10 or the wireless communication method configured as described above has the following characteristics.

  The wireless communication device 10 according to the present invention is configured to perform wireless data communication with an external device (information processing device 20) by selectively using any one of a plurality of channels (Wi-Fi). A communication unit 110), a wireless environment observation unit 120 configured to be able to observe a time change of the surrounding wireless environment, and a time and channel with less interference due to other wireless communication based on the observation result of the wireless environment observation unit 120 And a wireless communication environment determination unit 130 configured to be able to determine the above.

  According to the wireless communication device 10 configured as described above, it is possible to determine a time and a channel in which data can be efficiently transmitted and received with less interference due to other wireless communication in the vicinity.

  Further, in the wireless communication device 10 of the present invention, a data storage device configured to receive data from an external device (information processing device 20) based on the time and channel determined by the wireless communication environment determination unit 130 and to be able to store the data. The data storage / transmission control unit (CPU 100) is configured to be controllable to transmit the received data to the (storage device 30).

  According to the wireless communication device 10 configured as described above, the data storage device (storage device 30) is connected to the external device (information processing device 20) using the determined time and channel capable of efficiently transmitting and receiving data. ) Can be sent. As a result, it is possible to efficiently back up the data of the external device (information processing apparatus 20).

Further, in the wireless communication device 10 of the present invention, the wireless environment observation unit 120 observes a time change of the surrounding wireless environment by acquiring a radio beacon emitted by another wireless communication device. To do.

  According to the wireless communication device 10 having the above-described configuration, it is possible to observe a time change of the surrounding wireless environment using a wireless beacon (Beacon) widely used in wireless communication devices.

  Further, in the wireless communication device 10 of the present invention, the wireless environment observation unit (120) transmits and receives data through wireless communication with an external device (information processing device 20) to acquire the interference occurrence state, thereby It is characterized by observing changes in the wireless environment over time.

  According to the wireless communication device 10 having the above configuration, it is possible to observe a time change of the surrounding wireless environment by actually performing wireless communication with the external device (information processing device 20).

  Further, in the wireless communication device 10 of the present invention, the wireless environment observation unit (120) is characterized by observing temporal changes in the surrounding wireless environment by acquiring the packet amount in the surrounding wireless environment.

  According to the wireless communication apparatus 10 configured as described above, it is possible to observe the time change of the surrounding wireless environment by using the packet capture function.

  The wireless communication method of the present invention is a wireless communication method executed by a wireless communication device capable of transmitting and receiving data by wireless communication with an external device by selectively using any of a plurality of channels, A first step (S620) for observing a time change of the wireless environment of (2), a second step (S620) for determining a time and a channel with less interference due to other wireless communication based on the observation result in the first step, A third step (S670) of receiving data from the external device according to the time and channel determined in the second step and transmitting the received data to a data storage device configured to store the data. It is characterized by that.

  According to the wireless communication method having the above configuration, the data storage device (storage device 30) is connected to the external device (information processing device 20) using the determined time and channel at which data can be efficiently transmitted and received. Data received from can be transmitted. As a result, it is possible to efficiently back up the data of the external device (information processing apparatus 20).

  The present invention is preferably applied as a wireless communication apparatus having a function of effectively backing up data of connected devices.

DESCRIPTION OF SYMBOLS 10 ... Wireless communication apparatus 20 ... Information processing apparatus 30 ... Storage apparatus 110 ... Communication part 120 ... Wireless environment observation part 130 ... Wireless communication environment determination part 140 ... Interface part 160 ... Bus 210 ... Communication part 220 ... Display part 230 ... Operation input Part 260 ... Bus

Claims (6)

A wireless communication unit configured to be able to transmit and receive data by wireless communication with an external device selectively using one of a plurality of channels;
A wireless environment observation unit configured to be capable of observing temporal changes in the surrounding wireless environment;
A wireless communication environment determining unit configured to be able to determine a time and a channel with less interference due to other wireless communication based on an observation result of the wireless environment monitoring unit. It is configured to be able to receive data from an external device according to the time and channel determined by the wireless communication environment determination unit, and to transmit the received data to a data storage device configured to store the data. The wireless communication apparatus according to claim 1, further comprising a data transmission / reception control unit. The wireless communication device according to claim 1, wherein the wireless environment observation unit observes a time change of a surrounding wireless environment by acquiring a wireless sign emitted by another wireless communication device. . The wireless environment observation unit observes a time change of a surrounding wireless environment by transmitting and receiving data by wireless communication with an external device and acquiring an interference occurrence state. 2. A wireless communication device according to 2. The wireless communication apparatus according to claim 1, wherein the wireless environment observation unit observes a temporal change in the surrounding wireless environment by acquiring a packet amount in the surrounding wireless environment. A wireless communication method that is executed by a wireless communication device capable of transmitting and receiving data by wireless communication with an external device by selectively using one of a plurality of channels,
A first step of observing temporal changes in the surrounding wireless environment;
A second step of determining a time and a channel with less interference due to other wireless communication based on the observation result in the first step;
Receiving the data from the external device according to the time and channel determined in the second step, and transmitting the received data to a data storage device configured to store the data. A wireless communication method.

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