JP2009044384A - Radio communications equipment and radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide radio communications equipment capable of easily performing change setting of channels and further controlling timing for changing the channels. <P>SOLUTION: The radio communications equipment in one embodiment of the present invention is provided with a microcomputer 1, which determines the frequency channel used in radio communication; a radio chip 3 which receives information about the determined frequency channel from the microcomputer 1, to transmit and receive data with a plurality of devices using the determined frequency channel; and an infrared ray receiving module 2, which receives information for specifying the frequency channel to be transmitted to the microcomputer 1 by using infrared communication. When the infrared reception module 2 receives the information for specifying a frequency channel different from the frequency channel which is being used at the present by the infrared communication, the microcomputer 1 switches frequency channels of the radio chip 3 to a different frequency channel, transmits and receives the data with a plurality of devices by using the frequency channel after switching. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wireless communication device and a wireless communication system using the wireless communication device.

  FIG. 8 is a diagram illustrating a configuration of a conventional wireless communication apparatus having a wireless communication function. From the figure, the wireless communication device designates a microcomputer 21 that determines a frequency channel to be used in wireless communication, a wireless chip 23 that transmits / receives data to / from other wireless communication devices using the determined frequency channel, and a frequency channel. And a channel designation switch 22 for outputting the set value to the microcomputer 21.

  FIG. 9 is a diagram illustrating an illumination system that is one of wireless communication systems including a plurality of wireless communication devices. As shown in the figure, the lighting system includes a wall switch 71 and lighting fixtures 72 to 75. The wall switch 71 and the lighting fixtures 72 to 75 each incorporate the wireless communication device shown in FIG. 8, and by performing wireless communication with each other, lighting is turned on / off by operating the wall switch.

  Unlike infrared rays, wireless communication has low directivity, so there is no need to worry about the direction when installing or using a device. In addition, since the communication distance is long, application in various systems is considered. Usually, in such wireless communication, various frequency bands are used. However, in the 2.4 GHz band of the ISM band (Industrial Scientific and Medical band), a radio license is not required if the output is low. It has come to be used frequently.

  On the other hand, this ISM band, particularly the 2.4 GHz band, is used for communications such as wireless LAN (using IEEE802.11 standard), Bluetooth (using IEEE802.15.1 standard), ZigBee (using IEEE802.15.4 standard), etc. Therefore, if each standard is used at the same time, communication may be hindered by radio interference. FIG. 10 is a diagram showing the configurations of the IEEE 802.11 standard channels 97 to 99 and the IEEE 802.15.4 standard channels 81 to 96 in the 2.4 GHz band and their occupied frequencies.

  Next, with reference to FIGS. 8 to 10, the operation when changing the frequency channel used for wireless communication will be described. For example, it is assumed that data communication is first performed using the channel 81 which is wireless communication of the IEEE 802.15.4 standard. After that, when a wireless LAN is installed in the vicinity and the IEEE 802.11b channel 97 starts to be used for communication, the wireless communication state deteriorates due to interference with each other, the data communication rate decreases, or the worst data communication cannot be performed. There is a fear.

  In such a state, the conventional radio communication apparatus switches the frequency channel to be used by the channel designation switch 22. As the channel designation switch 22, for example, a dip switch or a rotary switch is used.

  Next, the microcomputer 21 reads the value of the channel designation switch 22, switches the wireless chip 23 to the frequency channel designated by this value, and performs wireless communication with other devices using the frequency channel after the switching. Here, when operating the wireless communication function, a value corresponding to a predetermined channel number is designated in this switch 21. When a problem such as wireless interference occurs, the person manually touches the value. The setting of the switch 21 was switched to change the channel used for wireless communication.

  The relationship between ZigBee and wireless LAN is disclosed in Non-Patent Document 1 below.

OTSL Inc., OTSL Column ZigBee and Wireless LAN, [online], June 15, 2005, OTSL Inc. [Search July 10, 2007], Internet <URL: http://www.otsl.jp/ zigbee / index.html>

  However, in the conventional wireless communication device, since the switch is switched manually by a person, for example, in order to change the setting of a lighting fixture installed at a high place such as a ceiling, it is necessary to perform the setting using a step board or the like. It was. Therefore, there is a problem that the setting is troublesome and takes time.

  In order to facilitate the setting, it is necessary to have a switch on the front of the device, but since the switch is provided on the front of the device, there is no freedom in design, and malfunctions caused by others. There was a problem such as.

  Furthermore, in the case of a lighting system having a large number of lighting devices, there has been a problem that the entire lighting system is not operating correctly until the channel to be used is switched by operating the switches of all the devices.

  Accordingly, the present invention has been made to solve such a problem, and it is an object of the present invention to provide a wireless communication apparatus that can easily perform channel change setting and control the timing for changing the channel.

  In the wireless communication device according to the embodiment of the present invention, when the infrared receiving module receives information specifying a frequency channel different from the frequency channel currently used by the wireless communication means by infrared communication, the microcomputer transmits the information to the different frequency channel. Switch the frequency channel of the wireless communication means. The wireless communication means transmits / receives data to / from a plurality of devices using the frequency channel after switching.

  In the wireless communication apparatus according to another embodiment of the present invention, the second wireless communication unit uses a specific frequency channel and the frequency channel different from the frequency channel currently used by the first wireless communication unit. Is received, the microcomputer switches the frequency channel of the first wireless communication means to the different frequency channel. The first wireless communication means transmits and receives data to and from a plurality of devices using the frequency channel after switching.

  In the wireless communication apparatus according to another embodiment of the present invention, the microcomputer switches the frequency channel of the wireless communication means to a specific frequency channel when the monitoring means of the wireless communication means determines that the communication state has deteriorated. In addition, when the wireless communication means receives the information specifying the frequency channel different from the frequency channel that has been used by using the specific frequency channel, the microcomputer uses the frequency channel that has been used until then. Switching the frequency channel of the wireless communication means to the different frequency channel. The wireless communication means transmits / receives data to / from a plurality of devices using the frequency channel after switching.

  According to the wireless communication apparatus in one embodiment of the present invention, a channel used in normal wireless communication can be set using infrared rays. As a result, it is possible to save the trouble of switching by hand contact. For example, even when switching by a switch is difficult, such as a lighting device installed on a ceiling, the channel can be easily and remotely changed.

  According to a wireless communication apparatus in another embodiment of the present invention, two wireless communication means are provided, and one wireless communication means uses a specific frequency channel, and the other wireless communication means performs normal wireless communication. You can set the channel to use. As a result, it is possible to save the trouble of switching by hand contact. For example, even when switching by a switch is difficult, such as a lighting device installed on a ceiling, the channel can be easily and remotely changed.

  According to the wireless communication apparatus in another embodiment of the present invention, the wireless communication unit includes a monitoring unit that monitors the wireless communication state. Therefore, if the wireless communication state deteriorates, a channel used for normal wireless communication is specified. Can switch to frequency channel. In addition, the wireless communication device can set a channel used in normal wireless communication using the specific frequency channel. As a result, it is possible to save the trouble of manually switching, and for example, even when switching by a switch is difficult as in a lighting device installed on a ceiling, it is possible to easily change a channel remotely.

<Embodiment 1>
FIG. 1 is a diagram showing a configuration of a wireless communication apparatus according to Embodiment 1 of the present invention. This wireless communication device receives a frequency channel determined from the microcomputer 1 that determines a frequency channel to be used in wireless communication, and transmits / receives data to / from a plurality of devices using the determined frequency channel. Wireless communication means (hereinafter referred to as a wireless chip 3) and an infrared receiving module 2 that receives information specifying a frequency channel using infrared communication and transmits the information to the microcomputer 1 are provided.

  In addition, the microcomputer 1 and the infrared receiving module 2 are connected to the microcomputer terminal 7 and the infrared module terminal 8 by the wiring 9, and normally, the microcomputer terminal 7 uses the interrupt input terminal of the microcomputer 1, thereby Infrared communication can be easily realized.

  FIG. 2 is a flowchart showing the operation of the microcomputer 1 of the wireless communication apparatus in the present embodiment. The wireless communication device performs data transmission / reception by wireless communication with a plurality of devices capable of wireless communication using any of the plurality of channels of the ISM band (S-11).

  Next, at a predetermined timing or at an arbitrary timing, the microcomputer 1 checks whether the infrared receiving module 2 has received information specifying the frequency channel from the infrared transmitting terminal (S-12).

  Next, if the infrared receiving module 2 is not receiving, normal wireless communication continues (S-11). On the other hand, if the infrared receiving module 2 receives information designating a frequency channel, and if it is information designating a frequency channel different from the currently used frequency channel, the microcomputer 1 sends the wireless chip 3 to this different frequency channel. Are switched (S-13).

  Next, the wireless chip 3 transmits / receives data to / from another wireless communication device using the new frequency channel after switching (S-11).

  In FIG. 2, it is described that S-11 and S12 are executed sequentially, but it is also possible to execute S-12 at an arbitrary timing using a software technique such as an interrupt processing routine. is there.

  Note that the infrared transmission terminal described above can be a portable terminal that is easy to carry. As a result, data indicating the channel change can be transmitted to each illumination device by operating the terminal by going to the side of each wireless communication device (for example, the illumination device).

  In addition, in the case of a lighting system where there are a large number of lighting devices, there is a problem that the entire lighting system does not operate correctly until switching to a frequency channel that designates the frequency channel of all devices. Can be transmitted including time information for channel change. When the infrared receiving module 2 receives the data including the time information, the microcomputer 1 uses the clock means provided in the microcomputer 1 to control the switching of the frequency channel at a timing corresponding to the time information.

  For example, when data is transmitted from the infrared transmission terminal to each lighting device, the remaining time until the channel change time is also transmitted as information, and each lighting device receives the channel from the time when the remaining time has elapsed after receiving the data from the infrared. To change. In this case, even when changing the channel setting for each of a large number of lighting devices using an infrared transmission terminal, the channels used by the lighting devices can be switched simultaneously at the same timing.

  As described above, the wireless communication device according to the present embodiment has an infrared communication function in addition to the ISM band wireless communication. Therefore, when wireless communication is hindered due to interference with other wireless standards. In addition, data can be received from other devices using infrared communication. Then, by giving an instruction to change the channel used for wireless communication by infrared communication, and changing the channel accordingly, wireless communication is performed using a channel that is not affected by interference by other wireless standards. Can do.

  As described above, the wireless communication apparatus according to the present embodiment can save the trouble of manually switching channels by using infrared communication, and is difficult to switch with a switch such as a lighting device installed on a ceiling. Even in this case, the channel can be easily changed remotely.

  Further, by including channel switching time information in infrared communication data, it becomes possible to switch channels used by a large number of lighting devices at the same timing.

  In the present embodiment, the channel switching information is transmitted. However, the data transmitted to each lighting device using infrared rays may be other setting parameters.

<Embodiment 2>
FIG. 3 is a diagram showing the configuration of the wireless communication apparatus according to Embodiment 2 of the present invention. This wireless communication device receives a frequency channel determined from the microcomputer 31 that determines a frequency channel to be used in wireless communication, and transmits / receives data to / from a plurality of devices using the determined frequency channel. Wireless communication means (hereinafter referred to as wireless chip 32), wireless communication means (hereinafter referred to as wireless chip 33) for receiving information specifying a frequency channel using a specific frequency channel and transmitting it to microcomputer 31; Is provided. That is, the infrared receiving module 2 in the first embodiment shown in FIG. 1 is replaced with the second wireless chip 33.

  Here, the specific frequency channel described above is a configuration setting channel. For example, in FIG. 10, a channel 96 having the highest frequency band is determined in advance as a channel used for configuration setting. As the setting channel, a channel that exists in a band that is not used in other wireless standards is selected as much as possible. The presence / absence of a channel that is not used in other wireless standards varies depending on the region of the world, but the most extreme channel is often applicable.

  If these channels are fixedly used as normal data communication channels, other wireless networks that use the same wireless standard in the surrounding area may all use this channel, resulting in increased collisions when using the channels. It is not preferable. Therefore, in normal wireless communication, it is preferable to select and use individual channels, and a configuration setting channel is used only when channel change is set.

  FIG. 4 is a flowchart showing the operation of the microcomputer 31 of the wireless communication apparatus according to the present embodiment. The wireless communication device transmits / receives data by wireless communication with a plurality of devices capable of wireless communication using any of the plurality of channels of the ISM band (S-41).

  Next, at a predetermined timing or at an arbitrary timing, the microcomputer 1 checks whether or not the wireless chip 33 has received information specifying a frequency channel from the wireless transmission terminal (S-42).

  Next, if the wireless chip 33 has not received, normal wireless communication continues (S-41). On the other hand, if the wireless chip 33 receives the information specifying the frequency channel, and if it is information specifying the frequency channel different from the currently used frequency channel, the microcomputer 1 assigns the wireless chip 32 to the different frequency channel. The frequency channel is switched (S-43).

  Next, the wireless chip 32 transmits / receives data to / from another wireless communication device using the new frequency channel after switching (S-41).

  In FIG. 4, it is described that data reception from the normal wireless communication channel and data reception from the configuration setting channel are executed sequentially, but both are received simultaneously by programming of the microcomputer 31. It is also possible to process.

  Further, similarly to Embodiment 1, the wireless transmission terminal can transmit the transmission data to be transmitted including the time information for performing channel change. When the wireless chip 33 receives the data including the time information, the microcomputer 31 can control the switching of the frequency channel at a timing corresponding to the time information using a clock means provided in the microcomputer 31.

  As described above, since the wireless communication apparatus according to the present embodiment includes the wireless chip 33 for setting the configuration separately from the wireless chip 32 used for normal wireless communication, the data on both channels are received simultaneously and constantly. It becomes possible to do. As a result, even if wireless interference occurs on the channel used for normal communication and communication cannot be performed, the configuration setting channel is used to send a change instruction to another channel, It can be sent from other devices.

  As described above, the wireless communication device according to the present embodiment can save the trouble of manually switching channels as in the case of the wireless communication device according to the first embodiment. For example, the wireless communication device can be switched like a lighting device installed on the ceiling. Even when switching by is difficult, it is possible to easily change the channel remotely.

  In addition, by including channel switching time information in the configuration setting data, it becomes possible for a large number of lighting devices to switch channels to be used at the same timing.

<Embodiment 3>
FIG. 5 is a diagram showing a configuration of a wireless communication apparatus according to Embodiment 3 of the present invention. This wireless communication device receives a frequency channel determined from the microcomputer 51 that determines a frequency channel to be used in wireless communication, and transmits / receives data to / from a plurality of devices using the determined frequency channel. Wireless communication means (hereinafter referred to as wireless chip 53) is provided. In addition, this wireless communication device includes a monitoring unit that uses the wireless chip 53 to monitor the communication state with a plurality of devices and determine whether the communication state has deteriorated. That is, the infrared receiving module 2 in the first embodiment is removed.

  FIG. 6 is a flowchart showing the operation of the microcomputer 51 of the wireless communication apparatus in the present embodiment. The wireless communication device transmits / receives data by wireless communication with a plurality of devices capable of wireless communication using any of the plurality of channels of the ISM band (S-61).

  Next, it is checked whether the monitoring means monitoring the communication state determines that the communication state has deteriorated (S-62).

  Next, if the communication state has not deteriorated, normal wireless communication is continued (S-61). On the other hand, if it is confirmed that the communication state has deteriorated, the frequency channel of the wireless chip 53 is changed to a channel for configuration setting (S-63).

  Next, for example, a configuration setting channel is set for a certain time, and the wireless chip 53 waits for reception of information specifying a frequency channel (S-64).

  Next, if there is no reception data, it returns to the original communication channel and performs normal wireless communication (S-65). On the other hand, if data specifying a frequency channel is received and the data is information specifying a frequency channel different from the frequency channel used so far, the microcomputer 51 transmits the frequency channel of the wireless chip 53 to the different frequency channel. (S-66).

  Next, the wireless chip 53 transmits / receives data to / from another wireless communication device using the new frequency channel after switching (S-61).

  Next, a method in which the monitoring unit using the wireless chip 53 evaluates that the communication state of the channel being used has deteriorated will be described below. In addition, processing on the side of transmitting information specifying a frequency channel will also be described.

  The first communication state deterioration evaluation method is a method of measuring the surrounding energy value in the channel band. In each wireless communication device, at the time of transmission or at an arbitrary time, the surrounding energy value in the channel band in use is measured, and when the energy value is larger than a certain reference or when the large state continues for a long time, It is determined that the communication state has deteriorated. Note that the normal wireless chip has a function of measuring the energy value of the corresponding channel.

  Next, after one device in the system determines that the communication status has deteriorated, it uses the configuration setting channel to send information specifying a frequency channel that is different from the frequency channel used so far to other wireless communications. Send to device. Accordingly, other wireless communication apparatuses can receive the data from the configuration setting channel. However, this method is limited to the case where all devices can detect the deterioration of the communication state.

  The second communication state deterioration evaluation method is a method for transmitting and receiving data for confirming normal operation between wireless communication devices. Each wireless communication device sends a data packet for confirmation indicating that it is operating normally to each other periodically using the channel being used. Is judged to have deteriorated.

  FIG. 7 is a diagram showing an application system in which the second communication state deterioration evaluation method is useful. FIG. 7 shows a configuration in which many lighting devices 101 to 116 are installed in an entire room 100 such as an office, and all lighting devices are turned on / off by a wall switch 120, for example. Each lighting device 101 to 116 periodically transmits wireless data indicating that it is operating normally to the wall switch 120, and the wall switch 120 transmits similar wireless data to each lighting device. Thereby, it is possible to confirm whether each device and the wall switch can normally perform wireless communication.

  Next, it is assumed that another type of wireless device 121 using the same frequency is installed in the same room, and wireless interference occurs. However, the range in which the radio interference interferes with communication is limited to the circle 122 shown in the figure. In this case, the wall switch 120 cannot receive wireless data for confirmation from the lighting devices 102, 103, 106, and 107 due to wireless interference, so that it can be determined that some kind of wireless communication failure has occurred in the system.

  Next, the wall switch 120 switches its own operation channel to a wireless channel for configuration setting, and transmits channel information used for new communication for a while. As a result, each lighting device can no longer receive data from the wall switch 120 in the previously used channel. Therefore, based on the flowchart of FIG. 6, the channel is switched to the configuration setting channel and receives new channel information from the wall switch 120. can do.

  As described above, the wireless communication apparatus according to the present embodiment is configured to use another wireless channel for configuration setting even when data communication becomes difficult due to interference with other wireless standards in the normal data communication channel. Since data for setting instructions can be received using the, it is possible to continue data communication using another designated radio channel. The operating time of the infrared receiving module 2 shown in the first embodiment and the operating time of the second wireless communication means (wireless chip 33) shown in the second embodiment are such that data communication is normally performed. When operating, the operation time is shortened, and intermittent operation is performed at a relatively long time interval T to reduce power consumption. Conversely, when data communication becomes difficult, the operation time may be longer, and an intermittent operation may be performed at a time interval t shorter than time T to facilitate resetting. In particular, even if nothing is set for each lighting device (communication device) immediately after installation of the lighting device, the operation is intermittently performed at a short time interval t and reset (in this case, the first setting). You may comprise so that it may be easy to do. The same applies to the switching to the configuration setting channel in the third embodiment, and the operation time and the switching frequency may be corrected so as to be suitable for the communication state. It may be configured to make the setting easier by setting the operation time longer and switching frequency higher.

  As described above, the wireless communication apparatus according to the present embodiment can save the trouble of manually switching channels as in the case of the wireless communication apparatus according to the first embodiment. For example, the wireless communication apparatus uses a switch like a lighting device installed on a ceiling. Even when switching is difficult, the channel can be easily changed remotely.

  Although the illumination system has been described as an example so far, the wireless communication device of the present invention is not limited to the illumination system.

  The wireless communication apparatus of the present invention can be applied to lighting systems such as buildings and air conditioning systems.

It is the figure which showed the structure of the radio | wireless communication apparatus in Embodiment 1 of this invention. It is the flowchart which showed operation | movement of the microcomputer of the radio | wireless communication apparatus in Embodiment 1 of this invention. It is the figure which showed the structure of the radio | wireless communication apparatus in Embodiment 2 of this invention. It is the flowchart which showed operation | movement of the microcomputer of the radio | wireless communication apparatus in Embodiment 2 of this invention. It is the figure which showed the structure of the radio | wireless communication apparatus in Embodiment 3 of this invention. It is the flowchart which showed operation | movement of the microcomputer of the radio | wireless communication apparatus in Embodiment 3 of this invention. It is the figure which showed the system using the evaluation method of the communication state deterioration in Embodiment 3 of this invention. It is the figure which showed the structure of the radio | wireless communication apparatus in a prior art. It is the figure which showed the radio | wireless communications system which consists of a some radio | wireless communication apparatus. It is the figure which showed the channel structure in a 2.4 GHz band.

Explanation of symbols

  1, 21, 31, 51 Microcomputer, 2 Infrared receiver module, 3, 23, 32, 33, 53 Wireless chip, 22 channel designation switch, 101-116 lighting device, 120 wall switch.

Claims (10)

A wireless communication device that transmits and receives data by wireless communication with a plurality of devices capable of wireless communication using any of a plurality of frequency channels,
A microcomputer for determining a frequency channel to be used in the wireless communication;
Radio communication means for receiving information on the determined frequency channel from the microcomputer and transmitting and receiving data to and from the plurality of devices using the determined frequency channel;
An infrared receiving module that receives information specifying the frequency channel using infrared communication and transmits the information to the microcomputer;
When the infrared receiving module receives information specifying a frequency channel different from the frequency channel currently used by infrared communication, the microcomputer switches the frequency channel of the wireless communication means to the different frequency channel, and the wireless communication means A wireless communication apparatus that transmits and receives data to and from the plurality of apparatuses using the frequency channel after switching. The microcomputer further includes a clock means,
The wireless communication apparatus according to claim 1, wherein when the infrared receiving module receives information specifying the frequency channel including time information, the microcomputer switches the frequency channel at a timing corresponding to the time information. A plurality of wireless communication devices according to claim 1 or 2,
An infrared transmission terminal that transmits information specifying the frequency channel using infrared communication, and
The wireless communication device receives information specifying the frequency channel from the infrared transmission terminal, and transmits / receives data to / from another wireless communication device using the frequency channel specified by the received information . A wireless communication device that transmits and receives data by wireless communication with a plurality of devices capable of wireless communication using any of a plurality of frequency channels,
A microcomputer for determining a frequency channel to be used in the wireless communication;
First wireless communication means for receiving information of the determined frequency channel from the microcomputer and transmitting and receiving data to and from the plurality of devices using the determined frequency channel;
Receiving the information specifying the frequency channel using a specific frequency channel and transmitting to the microcomputer, the second wireless communication means,
When the second wireless communication unit receives information specifying a frequency channel different from the currently used frequency channel by using a specific frequency channel, the microcomputer transmits the first wireless communication unit to the different frequency channel. A wireless communication device that switches frequency channels, and wherein the first wireless communication means transmits and receives data to and from the plurality of devices using the frequency channel after the switching. The microcomputer further includes a clock means,
The microcomputer switches the frequency channel of the first wireless communication means at a timing corresponding to the time information when the second wireless communication means receives information specifying the frequency channel including time information. A wireless communication device according to 1. A plurality of wireless communication devices according to claim 4 or 5,
A wireless transmission terminal that transmits information specifying the frequency channel using a specific frequency channel, and
The wireless communication apparatus receives information specifying the frequency channel from the wireless transmission terminal, and transmits / receives data to / from another wireless communication apparatus using the frequency channel specified by the received information . A wireless communication device that transmits and receives data by wireless communication with a plurality of devices capable of wireless communication using any of a plurality of frequency channels,
A microcomputer for determining a frequency channel to be used in the wireless communication;
Wireless communication means for receiving information on the determined frequency channel from the microcomputer and transmitting and receiving data to and from the plurality of devices using the determined frequency channel;
The wireless communication means further comprises monitoring means for monitoring the communication status with the plurality of devices to determine whether the communication status has deteriorated,
When the monitoring unit determines that the communication state has deteriorated, the microcomputer switches the frequency channel of the wireless communication unit to a specific frequency channel, and uses the specific frequency channel and the frequency channel used so far. When the wireless communication means receives information designating a different frequency channel, the microcomputer switches the frequency channel of the wireless communication means from the frequency channel used so far to the different frequency channel, and the wireless communication means A wireless communication device that transmits and receives data to and from the plurality of devices using a frequency channel after switching.   The radio communication apparatus according to claim 7, wherein the monitoring unit measures an energy value in a channel band of the frequency channel to be used, and determines that the communication state has deteriorated if the energy value exceeds a predetermined energy value. The wireless communication means has a function of transmitting and receiving data for confirming that it is operating normally with another wireless communication device that performs wireless communication,
The wireless communication apparatus according to claim 7, wherein the monitoring unit determines that a communication state has deteriorated if the data cannot be received from the other wireless communication apparatus. A plurality of wireless communication devices according to any one of claims 7 to 9,
One of the plurality of wireless communication devices uses a specific frequency channel for another wireless communication device when the monitoring unit determines that the communication state has deteriorated. Send information specifying a different frequency channel, and
The other wireless communication device receives information specifying the different frequency channel from the one wireless communication device, and transmits / receives data to / from the plurality of wireless communication devices using the frequency channel specified by the received information. A wireless communication system.

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