JP2012248939A - Radio communication device, radio communication system, radio communication control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient radio communication system having good communication quality, using a communication radio channel with a small influence of another system in an overall radio communication system.SOLUTION: A radio communication device (master equipment) requests a radio communication device (slave equipment) to measure electric field intensity in a channel frequency of an available radio channel (step S102), and also in an electric field intensity measurement unit of the radio communication device (master equipment), measures electric field intensity of the channel frequency (step S103). The radio communication device (master equipment) receives and acquires the measurement information of the electric field intensity measured by the radio communication device (slave equipment) (step S104). From the measurement information acquired in the steps S103 and S104, a communication radio channel for use in the radio communication system is determined (step S106). Using the communication radio channel, each radio communication device performs radio communication with another radio communication device.

Description

  The present invention relates to a wireless communication device, a wireless communication system, a wireless communication control method, and a program.

  Since the wireless communication system performs communication using radio waves in a specific frequency band, the radio communication system is easily affected by radio waves generated from peripheral devices. In particular, the closer the frequency of the radio wave is, the more easily affected by interference and the like, and other systems using the same frequency band can be a major factor that disturbs wireless communication.

For this reason, in each frequency band, a plurality of radio channels whose frequencies are shifted little by little are defined by a standard or the like. By using different radio channels for each system, interference can be avoided and efficient communication can be realized. For example, in the 2.4 GHz band (2400 to 2495 MHz) widely used for wireless LAN and the like, the following wireless channels are defined.
(Example of 2.4 GHz band radio channel)
Channel 1: 2412 MHz
Channel 2: 2417 MHz
Channel 3: 2422 MHz
Channel 4: 2427MHz
Channel 5: 2432 MHz
Channel 6: 2437 MHz
(Omitted)
Channel 13: 2472 MHz

  When a specific system communicates with one of the radio channels, the frequency band of the radio channel is occupied by that system. Therefore, in the wireless communication system, in order to reduce the influence of interference with other systems, it is necessary to select a free channel from these channels and perform communication using the channel.

  Here, whether or not another system is using a specific radio channel can be determined based on the maximum value or average value within a predetermined time by measuring the electric field strength at the channel frequency. A wireless communication system that uses this technique to measure the electric field strength of an available wireless channel and selects a wireless channel to be used based on the measurement result is known (see, for example, Patent Document 1).

  In the wireless communication system described in Patent Document 1, one wireless communication device (master) belonging to this wireless communication system repeats the electric field strength in each of a plurality of wireless channels that can be used for wireless communication a plurality of times. Then, the measured value is compared with the threshold value, and the wireless channel with the largest number of times the electric field strength is less than the threshold value is determined as the communication wireless channel.

JP 2010-103665 A

  In the wireless communication system of Patent Document 1, a communication wireless channel to be used by the wireless communication system is determined based on a result of electric field strength measurement of a parent device belonging to this system. For this reason, it is possible to select a communication radio channel suitable for the state of the electric field strength around the parent device where the electric field strength measurement has been performed, but the communication wireless channel communicates directly or indirectly with the parent device. It is not suitable for the state of electric field intensity around other wireless communication devices (child devices), and the entire wireless communication system may be affected by other systems, resulting in reduced efficiency and lower communication quality. .

  For example, if another system is located far from the master unit and close to the slave unit, even if the other system is communicating, the electric field strength in the channel used by the other system is weak around the master unit. Then, the electric field strength of the channel increases. In such a case, even if the communication wireless channel determined based on the electric field strength measurement information of the parent device is used, the communication between the parent device and the child device is hindered due to the influence of other systems.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wireless communication apparatus and the like capable of performing communication using a communication wireless channel that is less affected by other systems in the entire wireless communication system. .
Another object of the present invention is to provide a wireless communication apparatus and the like capable of efficient and high-quality communication.

In order to achieve the above object, a wireless communication device of the present invention provides:
Wireless communication means for transmitting and receiving wireless signals to and from other wireless communication devices using a predetermined communication wireless channel selected from a plurality of wireless channels;
Electric field strength measuring means for measuring electric field strength in each of the plurality of wireless channels;
Measurement information acquisition means for acquiring measurement information indicating the electric field strength in each of the wireless channels measured by the other wireless communication device from information received by the wireless communication device from the other wireless communication device;
Based on the electric field strength in each of the radio channels measured by the electric field strength measurement means and the electric field strength in each of the radio channels indicated by the measurement information acquired by the measurement information acquisition means, the predetermined communication radio A radio channel determining means for determining a channel;
Wireless communication control means for controlling the wireless communication means to transmit and receive wireless signals to and from the other wireless communication device using the communication wireless channel determined by the communication wireless channel determination means;
It is characterized by having.

  According to the present invention, efficient and high-quality communication using a communication wireless channel that is less affected by other systems is possible in the entire wireless communication system.

1 is a diagram illustrating a configuration including a wireless communication system according to a first embodiment. 1 is a block diagram illustrating an internal configuration of a wireless communication apparatus (master unit) according to Embodiment 1. FIG. 1 is a block diagram illustrating an internal configuration of a wireless communication device (child device) according to Embodiment 1. FIG. 4 is a flowchart showing channel setting processing (master device) executed by the wireless communication apparatus (master device) according to Embodiment 1; It is a figure which shows the example of the electric field strength measurement result of a radio | wireless communication apparatus (parent | mobile_unit) and a radio | wireless communication apparatus (child | mobile_unit). 4 is a flowchart showing channel setting processing (slave unit) executed by the wireless communication apparatus (slave unit) according to Embodiment 1; It is a sequence diagram which shows the flow of data between a radio | wireless communication apparatus (parent | mobile_unit) and a radio | wireless communication apparatus (slave_device). 7 is a flowchart showing channel setting processing (master device) executed by a wireless communication apparatus (master device) according to Embodiment 2. 10 is a flowchart showing channel setting processing (slave unit) executed by the wireless communication apparatus (slave unit) according to the second embodiment.

Embodiment 1 FIG.
A radio communication system according to Embodiment 1 of the present invention will be described in detail with reference to the drawings.

  A wireless communication system 1 according to the first embodiment includes wireless communication devices 11, 12, and 13 shown in FIG.

  In FIG. 1, a wireless communication device 11 constituting the wireless communication system 1 functions as a parent device, and the wireless communication devices 12 and 13 function as child devices.

  There may be a plurality of other wireless communication systems in the operating environment of the wireless communication system 1. For example, as illustrated in FIG. 1, the wireless communication system 1 including the wireless communication devices 21, 22, and the wireless communication devices 31 and 32 are included in the operating environment of the wireless communication system 1 including the wireless communication devices 11, 12, and 13. There may be a wireless communication system 3.

  The wireless communication device 11 serving as the parent device may be a device designated in advance, or may cause the wireless communication device activated first in the system to function as the parent device. In the following description, the wireless communication device 11 is referred to as a wireless communication device (parent device) 11, and the wireless communication devices 12 and 13 are referred to as wireless communication devices (child devices) 12 and 13, respectively. In order to facilitate understanding, two wireless communication devices (slave devices) are illustrated in FIG. 1, but the number of wireless communication devices (slave devices) is arbitrary. It may be above.

  The wireless communication device (parent device) 11 is a wireless communication device having a function of transmitting and receiving data to and from the wireless communication devices (child devices) 12 and 13 through wireless communication, and operates the wireless communication system 1 normally. Transmission / reception of data including information for the user and data transmission / reception based on user operations.

  In the present embodiment, the wireless communication device (parent device) 11 receives information data including the electric field strength for each wireless channel measured by the wireless communication devices (child devices) 12 and 13, and the electric field measured by the own device 11. Together with the intensity measurement information, a radio channel for communication that can provide the best communication environment as a whole of the radio communication system 1 is determined, and by using the radio channel for communication, Wireless communication.

  As shown in FIG. 2, the wireless communication device (base device) 11 includes an antenna 111, a wireless circuit 112, an electric field strength measurement unit 113, a data communication unit 114, a control unit 115, a storage unit 116, and an operation unit. 117 and a display unit 118.

  The antenna 111 is connected to the radio circuit 112. Although the configuration of the antenna 111 is arbitrary, for example, it is configured by a dipole antenna because of its simple configuration. The antenna 111 converts an electric signal output from the radio circuit 112 into a radio signal and radiates it, receives a radio signal transmitted from another radio communication circuit, converts it into an electric signal, and converts the radio signal into an electric signal. Output to.

  The radio circuit 112 is connected to the antenna 111 and the electric field strength measurement unit 113 and includes a reception circuit and a transmission circuit.

  The transmission circuit of the radio circuit 112 operates in accordance with the communication control signal supplied from the data communication unit 114, modulates a carrier wave with the signal (baseband signal) supplied from the data communication unit 114, and transmits the frequency of the communication radio channel. A band signal is generated and output to the antenna 111. On the other hand, the receiving circuit of the radio circuit 112 operates in accordance with the communication control signal supplied from the data communication unit 114, extracts a signal in a frequency band corresponding to the radio channel for communication from the electric signal output from the antenna 111, and extracts this signal. The baseband signal is reproduced by demodulating and output to the data communication unit 114. Here, the communication radio channel is a channel selected in a channel setting process to be described later from a radio channel designated in advance in the radio communication system according to the present embodiment. For example, it is channel 3 (2422 MHz) selected from the above-described 2.4 GHz band radio channels 1 to 13.

  The receiving circuit of the radio circuit 112 sequentially extracts an electric signal in a frequency band corresponding to each radio channel from the electric signals output from the antenna 111 according to the communication control signal supplied from the data communication unit 114, and Output to the intensity measuring unit 113. For example, electrical signals in the frequency bands of all the 2.4 GHz band radio channels 1 to 13 described above are sequentially output to the electric field strength measuring unit 113.

  The electric field strength measuring unit 113 is connected to the radio circuit 112 and the control unit 115 and operates according to the control of the control unit 115. As described above, the electric field strength measurement unit 113 is sequentially input with electrical signals in frequency bands corresponding to the respective radio channels from the reception circuit of the radio circuit 112. The electric field strength measuring unit 113 sequentially measures electrical signal strength (RSSI; Receive Signal Strength Indication) at the input timing of the electrical signal of each channel in accordance with the control of the control unit 115, so that the measurement target wireless channel (for example, 2. Obtain the field strength of the 2.4 GHz band wireless channels 1-13).

  The electric field strength measurement unit 113 outputs measurement information based on the electric field strength of each wireless channel obtained by measurement to the control unit 115.

  The data communication unit 114 is connected to the radio circuit 112 and the control unit 115. The data communication unit 114 outputs a communication control signal for controlling transmission by the transmission circuit of the wireless circuit 112 to the wireless circuit 112 under the control of the control unit 115. This communication control signal is a signal including radio channel information designated by the control unit 115. In addition, the data communication unit 114 converts the data signal output from the control unit 115 into a signal (baseband signal) compliant with the wireless communication standard, and outputs the signal to the transmission circuit of the wireless circuit 112.

  In addition, the data communication unit 114 outputs a communication control signal to the reception circuit of the wireless circuit 112 according to the control of the control unit 115 and also outputs a signal (baseband signal) output from the reception circuit of the wireless circuit 112 to the control unit 115. Is converted into a data format that can be handled by the control unit 115 and output to the control unit 115.

  The control unit 115 includes an arithmetic device, a control device, and the like, and by executing a program stored in the storage unit 116, a wireless communication device (including a wireless circuit 112, an electric field strength measurement unit 113, and a data communication unit 114) ( Program processing for realizing the functions of the wireless communication device (parent device) 11 such as control of each component of the parent device 11 and channel setting processing described later is performed.

  The control unit 115 controls the wireless transmission using the communication wireless channel by outputting a communication control signal from the data communication unit 114 to the transmission circuit of the wireless circuit 112. Further, the control unit 115 controls wireless reception using the communication wireless channel by causing the data communication unit 114 to output a communication control signal to the reception circuit of the wireless circuit 112.

  That is, the control unit 115 controls the radio circuit 112 so that the radio transmission data is transmitted from the transmission circuit of the radio circuit 112 using the carrier wave of the communication radio channel. In addition, the radio circuit 112 is controlled so that a signal in the frequency band of the communication radio channel is extracted from the electric signal input to the reception circuit of the radio circuit 112.

  In addition, the control unit 115 generates data to be transmitted and outputs the data to the data communication unit 114, or obtains reception data converted from the baseband signal by the data communication unit 114 and performs data processing. In the channel setting process of the present embodiment, when an electric field strength measurement request is made to the wireless communication devices (slave units) 12 and 13, data including measurement conditions such as a measurement target wireless channel is output. Further, when the measurement information of the electric field strength measured by the wireless communication devices (slave devices) 12 and 13 is acquired, data including the measurement information is acquired via the antenna 111, the wireless circuit 112, and the data communication unit 114.

  In addition, in order to measure the electric field strength in the wireless communication device (master device) 11, the control unit 115 causes the wireless circuit 112 to extract an electric signal in a frequency band corresponding to each wireless channel to be measured. 112 is controlled. In addition, the electric field strength measurement unit 113 controls the electric field strength measurement unit 113 so that the electric field strength measurement unit 113 measures the electric field strength in accordance with the extraction timing of the electric signal and outputs the measurement value.

  In addition, the control unit 115 causes the storage unit 116 to store data including the electric field strength measurement information acquired from the wireless communication device (child device) 12 and the electric field strength measurement information measured by the electric field strength measurement unit 113. In addition, program processing for temporarily storing the information in the temporary storage unit built in the control unit 115 and displaying information based on the temporarily stored data on the display unit 118 or realizing functions such as a channel setting processing function. The data signal is used.

  The storage unit 116 includes, for example, a readable / writable nonvolatile semiconductor memory such as a flash memory. The storage unit 116 executes a program executed by the control unit 115, condition data referred to by the program, wireless communication data, and user operation. Stores input data and the like. The data stored in the storage unit 116 can be rewritten by a user operation input to the operation unit 117 or a control of the control unit 115.

  The storage unit 116 also stores information such as a list of radio channels that can be used in the radio communication system 1 and field strength measurement conditions, which are used in channel setting processing described later.

  The operation unit 117 includes various key buttons such as a direction key, a determination key, and a function key, a dial, and the like, receives an operation input from the user, and outputs a signal related to the received operation input to the control unit 115. The operation unit 117 receives a data transmission request, an input operation of data to be transmitted, and the like from the user.

  The display unit 118 includes a display device such as an LCD (Liquid Crystal Display) or an organic EL (Electro-Luminescence) display, and performs information display output such as images, figures, characters, symbols, and the like. The display unit 118 displays data received by wireless communication, data to be transmitted input by the user, and the like.

  As shown in FIG. 3, the wireless communication device (child device) 12 includes an antenna 121, a wireless circuit 122, an electric field strength measuring unit 123, a data communication unit 124, a control unit 125, a storage unit 126, an operation unit 127, And a display unit 128. The wireless communication device (slave device) 13 includes the same components as the wireless communication device (slave device) 12.

  Each functional unit of the wireless communication device (slave device) 12 has the same function as each functional unit having the same name as the wireless communication device (parent device) 11.

  The control unit 125 of the wireless communication device (slave unit) 12 performs the same function as the control unit 115 of the wireless communication device (base unit) 11 and measures the electric field intensity transmitted from the wireless communication device (base unit) 11. When a signal including a request is received, the radio circuit 122 and the electric field strength measurement unit 123 are controlled to perform electric field strength measurement based on the electric field strength measurement request. That is, in order to measure the electric field strength in the wireless communication device (child device) 12, the control unit 125 causes the wireless circuit 122 to extract an electrical signal in a frequency band corresponding to each wireless channel to be measured. To control. In addition, the electric field intensity measurement unit 123 controls the electric field intensity measurement unit 123 so that the electric field intensity measurement unit 123 performs electric field intensity measurement in accordance with the extraction timing of the electric signal and outputs the measurement value.

  In addition, when the measurement information obtained by measuring the electric field strength in accordance with the electric field intensity measurement request is input from the electric field intensity measurement unit 123 to the control unit 125, the control unit 125 transmits the measurement information to the wireless communication device (master device) 11. The wireless circuit 112 is controlled via the data communication unit 124 so as to transmit the data. The field strength measurement information is transmitted in response to a transmission request from the wireless communication device (master unit) 11, for example.

  A channel setting process in the wireless communication system 1 configured as described above will be described with reference to FIGS.

  The wireless communication device (master device) 11 and the wireless communication devices (slave devices) 12 and 13 belonging to the wireless communication system 1 are powered on to the wireless communication device (parent device) 11 or power is supplied to each wireless communication device. Initial setting of each device is performed at the timing of the input. For example, as a normal initial setting of a wireless communication device belonging to the wireless communication system 1, setting of a PANID that is a system identifier and an address that is an identifier of the wireless communication device is executed. In the case of a system in which the base unit is not designated in advance and the wireless communication device that is first turned on functions as the base unit, the wireless communication device that is turned on first is It also sets a flag indicating that the own apparatus is a wireless communication apparatus (master unit) 11.

  After executing the initial setting, the control unit 115 of the wireless communication apparatus (master unit) 11 starts the channel setting process shown in the flowchart of FIG.

  Until a communication wireless channel to be used is determined, a temporary communication wireless channel is set at the time of initial setting. The temporary communication wireless channel may be a predesignated channel stored in the storage units 116 and 126, or may be set manually at the time of startup.

  First, the control unit 115 of the wireless communication apparatus (parent device) 11 reads a list of channels that can be used in the wireless communication system 1 from the storage unit 116 (step S101). The control unit 115 controls the transmission circuit of the wireless circuit 112 via the data communication unit 114 so as to transmit a wireless signal including information requesting electric field strength measurement to the wireless communication devices (child devices) 12 and 13. (Step S102). At this time, the information requesting the electric field strength measurement includes measurement conditions such as the channel frequency, the measurement time, and the number of measurements read out in step S101.

  Thereafter, the control unit 115 measures the electric field strength of each channel based on the channel information read in step S101 (step S103). Specifically, the receiving unit of the radio circuit 112 is controlled to extract an electric signal in a frequency band corresponding to each radio channel to be measured, and the electric field intensity measuring unit 113 is controlled to perform electric field intensity measurement. . When the control unit 115 acquires the measurement value of each channel from the electric field intensity measurement unit 113, the control unit 115 compares it with a preset threshold value.

  The measurement of the electric field strength and the comparison with the threshold value are repeated a plurality of times. And the frequency | count that the electric field strength exceeded the threshold value for every radio channel for communication is counted. As for the number of measurements, for example, assuming that the communication of another system existing in the vicinity has a transmission time of 100 msec and a transmission interval of 1000 msec, it is considered that the presence of the other system can be detected with 10 or more measurement times.

  On the other hand, the wireless communication devices (slave devices) 12 and 13 that have received the electric field strength measurement request from the wireless communication device (parent device) 11 measure the electric field strength, and then set the measurement values for each channel in advance. And the number of times that the threshold value is exceeded is transmitted to the wireless communication device (parent device) 11. The control unit 115 of the wireless communication device (master unit) 11 receives transmission signals of the wireless communication devices (slave devices) 12 and 13 via the antenna 111, the wireless circuit 112, and the data communication unit 114. The number of times that the electric field strength for each radio channel exceeds the threshold is acquired (step S104). The control unit 115 stores data indicating the number of times the threshold has been exceeded in the storage unit 116.

  The control unit 115 adds the number of times that the electric field strength measurement value acquired in steps S103 and S104 and stored in the storage unit 116 exceeds a preset threshold for each channel. A channel whose value is 0 is determined as a free channel (step S105), and a communication radio channel to be used is determined from the free channels (step S106). The method for determining the communication radio channel to be used may be, for example, the channel with the smallest channel number among the empty channels, the channel with the largest channel number, or may be selected at random. If there is no empty channel, for example, the channel having the smallest total number of times that the measured value of the electric field intensity exceeds a preset threshold value is set.

  The procedure for determining the channels from step S103 to S106 will be described with reference to the example of FIG. FIG. 5A shows an example of measurement results measured by the electric field strength measurement unit 113 of the wireless communication device (master unit) 11 in a state where the wireless communication systems 1, 2, and 3 shown in FIG. An example of a measurement result measured by the electric field strength measurement unit 123 of the wireless communication device (child device) 12 is shown in FIG. In this example, the electrical signals in the frequency bands of channels 1 to 6 are extracted and VSSI is measured, and the number of measurements is 20 times. FIGS. 5A and 5B show the number of times that the measured value for each channel exceeds a preset threshold value.

  In this example, the wireless communication system 2 uses channel 2 and the wireless communication system 3 uses channel 5.

  As shown in FIG. 5A, the number of times that the measured value of the electric field strength of the channel 5 measured by the electric field strength measuring unit 113 of the wireless communication device (master device) 11 in step S103 exceeds the threshold is 3. In step S105, it can be determined that channel 5 is not an empty channel. However, since the number of times that the measured value of the electric field strength of channel 2 exceeds the threshold is 0, if it is determined based only on the measurement information of the wireless communication device (master unit), channel 2 is also an empty channel in step S105. It will be determined. Actually, however, there is a wireless communication system 2 using the channel 2 in the vicinity of the wireless communication device (slave unit) 12. Therefore, if channel 2 is used for wireless communication with the wireless communication device (slave unit) 12, interference occurs. The effect of etc. becomes large.

  On the other hand, as shown in FIG. 5B, the measured values of the channel 2 and channel 5 field strengths measured by the field strength measurement unit 123 of the wireless communication device (slave unit) 12 acquired in step S104 exceeded the threshold value. Since the number of times is 2, it can be determined that neither channel 2 nor 5 is an empty channel.

  The total number of times acquired in steps S103 and S104 is shown in FIG. In step S105, since the channel whose total number is 0 is determined as an empty channel, channels 3, 4, and 6 are determined as empty channels. Therefore, in step S106, channel 3 having the smallest channel number among the free channels is selected as the communication radio channel.

  Therefore, in the example shown in FIGS. 1 and 5, it is possible to select the channel 3 having a small influence of the wireless communication systems 2 and 3 existing in the vicinity.

  The control unit 115 outputs a data signal including information on the selected communication wireless channel to the data communication unit 114 and wirelessly transmits a signal based on the data signal to the wireless communication device (child device) 12. Next, the transmission circuit of the radio circuit 112 is controlled (step S107).

  Thereafter, in order to set a wireless channel for communication in the wireless circuit 112, the control unit 115 controls the wireless circuit 112 via the data communication unit 114 (step S108). The wireless circuit 112 performs wireless communication with the wireless communication devices (slave devices) 12 and 13 using the communication wireless channel.

  Next, the processing operation of the control unit 125 of the wireless communication apparatus (child device) 12 will be described with reference to FIG. After initial setting, the channel setting process shown in the flowchart of FIG. 6 is started.

  The control unit 125 of the wireless communication device (child device) 12 determines whether a request for electric field strength measurement has been received from the wireless communication device (parent device) 11 (step S201). When the request is received (step S201: Yes), the process proceeds to step S202, and waits until the step S201 is repeatedly received while the request is not received.

  The request for electric field strength measurement received by the wireless communication device (child device) 12 from the wireless communication device (parent device) 11 includes information such as the channel frequency for measuring the electric field strength, the measurement time, and the number of measurements. When the request is received, the control is performed such that the electric field strength measuring unit 123 measures the electric field strength (step S202). Specifically, the reception unit of the radio circuit 122 controls the radio circuit 122 so as to extract an electric signal in a frequency band corresponding to each radio channel to be measured. In addition, the electric field intensity measurement unit 123 controls the electric field intensity measurement unit 123 so that the electric field intensity measurement unit 123 performs electric field intensity measurement in accordance with the extraction timing of the electric signal and outputs the measurement value. When the control value of each channel is acquired from the electric field strength measurement unit 123, the control unit 125 compares the measured value with a preset threshold value.

  The measurement of the electric field strength and the comparison with the threshold value are repeated a plurality of times. And the frequency | count that the electric field strength exceeded the threshold value for every radio channel for communication is counted. As for the number of measurements, for example, assuming that the communication of another system existing in the vicinity has a transmission time of 100 msec and a transmission interval of 1000 msec, it is considered that the presence of the other system can be detected with 10 or more measurement times.

  When the counting of the number of times that the electric field strength exceeds the threshold is completed, the control unit 125 transmits the counting result as electric field strength measurement information from the wireless circuit 122 to the wireless communication device (parent device) 11. Transmission of the electric field strength measurement information is performed as a response to a request from the wireless communication apparatus (master unit) 11.

  Thereafter, it waits until information including a communication radio channel used in the wireless communication system 1 determined by the wireless communication device (parent device) 11 is sent from the parent device (step S204). When the communication wireless channel information is received, the received communication wireless channel is set in the wireless circuit 122 (step S205). The wireless circuit 122 wirelessly communicates with the wireless communication device (parent device) 11 and other child devices using the communication wireless channel.

  Next, a data flow between the wireless communication apparatus (master unit) 11 and the wireless communication apparatus (slave unit) 12 until a communication wireless channel is set will be described with reference to the sequence diagram of FIG. This sequence diagram describes only data transmission / reception between the wireless communication device (master device) 11 and the wireless communication device (slave device) 12. When there are two or more wireless communication devices (slave devices), multicast transmission is performed from the wireless communication device (master device) 11 to a plurality of wireless communication devices (slave devices), and a plurality of wireless communication devices (slave devices) are transmitted. ) Receives all the responses from), and determines a wireless channel for communication based on it.

  The wireless communication device (master device) 11 transmits a measurement parameter setting request to the wireless communication device (slave device) 11 (step S301). The measurement parameters that require setting include the channel frequency of the wireless channel to be measured, the measurement time, and the number of measurements. The channel frequency is, for example, the above-described 2.4 GHz band channel frequency. For example, when the transmission time of another system existing in the vicinity is predicted to be 100 msec, the measurement time is set to 100 msec.

  When receiving the measurement parameter setting request transmitted from the wireless communication device (master device) 11 in step S301, the control unit 125 of the wireless communication device (slave device) 12 sets the received measurement parameter (step S302).

  When the measurement parameter setting is completed, the control unit 125 of the wireless communication device (slave device) 12 transmits a measurement parameter setting response to the wireless communication device (parent device) 11. As the setting response, for example, setting success or setting failure is transmitted (step S303).

  When receiving the measurement parameter setting response transmitted from the wireless communication apparatus (slave unit) 12 in step S303, the control unit 115 of the wireless communication apparatus (master unit) 11 transmits a measurement start request to the wireless communication apparatus (slave unit) 12. (Step S304).

  When receiving the measurement start request transmitted from the wireless communication device (master unit) 11 in step S304, the control unit 125 of the wireless communication device (slave unit) 12 causes the wireless communication device (master unit) 11 to transmit a measurement start response. (Step S305).

  The control unit 125 of the wireless communication device (slave device) 12 waits for a predetermined time after transmitting the measurement start response in step S305. This is to wait until the wireless communication apparatus (master unit) 11 correctly receives the measurement start response. When the wireless communication device (parent device) 11 does not correctly receive the measurement start response, the wireless communication device (parent device) 11 may transmit a measurement start request to the wireless communication device (child device) 12 again. If the wireless communication device (slave unit) 12 measures the electric field strength during the measurement start request transmission, the communication of the own system is measured. To avoid this, wait for a certain time. The fixed time is determined from, for example, the response waiting time for the request, the communication time required for retransmission, and the number of retransmissions. If the response waiting time is 110 msec, the communication time required for retransmission is 100 msec, and the number of retransmissions is 2, 420 msec (= (110 + 110) X2). The waiting time may be a predetermined time or may be set as a parameter in step S301.

  The control unit 125 of the wireless communication device (child device) 12 causes the electric field strength measurement unit 123 to perform electric field strength measurement after waiting for a predetermined time in step S306 (step S307). The measurement conditions at this time are conditions based on the measurement parameters received in step S301.

  On the other hand, when the control unit 115 of the wireless communication apparatus (master unit) 11 also receives a measurement start response from the wireless communication apparatus (slave unit) 12 in step S305, the electric field strength measurement unit 113 measures the field strength after waiting for a predetermined time. (Step S308). The measurement conditions at this time are the same conditions as the measurement parameters transmitted in step S301. In addition, the electric field strength measuring units 113 and 123 are controlled so that the measurement timings of the wireless communication device (master device) and the wireless communication device (slave device) are substantially the same.

  The control unit 125 of the wireless communication device (slave device) 12 transmits a measurement end notification from the wireless circuit 112 after the completion of the electric field strength measurement in step S307 (step S309).

  Upon receiving the measurement end notification transmitted from the wireless communication device (slave device) 12 in step S309, the control unit 115 of the wireless communication device (master device) 11 sends the wireless communication device (slave device) 12 to the wireless communication device (slave device) 12 from the wireless circuit 112. A measurement information request is transmitted (step S310).

  When receiving the measurement information request transmitted from the wireless communication device (parent device) 11 in step S <b> 310, the control unit 125 of the wireless communication device (child device) 12 sends the wireless communication device (parent device) 11 to the wireless communication device (parent device) 11. A measurement information response is transmitted (step S311). The measurement information included in the measurement information response is a result of counting, for each channel, the number of times that the electric field intensity measurement unit 123 of the wireless communication device (child device) 12 has exceeded the predetermined threshold value measured in step S307. is there.

  The control unit 115 of the wireless communication device (master device) 11 measures the measurement information based on the electric field strength measured in step S308 and the measurement information included in the measurement information responses received from the plurality of wireless communication devices (slave devices) in step S311. Based on, a communication radio channel to be used for radio communication is determined (step S312).

  The control unit 115 of the wireless communication device (parent device) 11 notifies the wireless channel for communication determined in step S312 to all wireless communication devices (child devices) including the wireless communication devices (child devices) 12 and 13. (Step S313).

  Thereafter, the control unit 115 of the wireless communication apparatus (master unit) 11 sets the channel of the wireless circuit 112 to the communication wireless channel determined in step S312 (step S314), and the control unit 125 of the wireless communication apparatus (slave unit) 12 is set. Sets the channel of the radio circuit 121 to the communication radio channel notified in step S313 (step S315). In addition, when performing multicast transmission to a plurality of wireless communication devices (slave devices) and notifying each device of the communication wireless channel, each wireless communication device (slave device) was notified of the channel of the wireless circuit Set to the communication wireless channel.

  In the present embodiment, as shown in the sequence diagram of FIG. 7, the channel control unit of the wireless communication device (master unit) 11 may proceed to the next step by sequentially transmitting responses to requests. Or whether to repeat the same step.

  As described above, the wireless communication system 1 according to the present embodiment performs field strength measurement in the wireless communication device (master device) 11 and at least one or more wireless communication devices (slave devices) 12 and 13 to perform wireless communication. Since the radio channel for communication is determined based on the electric field strength measurement information of the device (base unit) 11 and the radio communication units (slave units) 12 and 13, the radio channel for communication having a small influence on other systems is selected. Thus, efficient and high-quality communication is possible in the entire wireless communication system.

Embodiment 2. FIG.
A second embodiment of the present invention will be described with reference to FIGS. The configuration of radio communication system 1 according to the present embodiment and the internal configuration of radio communication device (master device) 11 and radio communication devices (slave devices) 12 and 13 are the same as those in the first embodiment. Since the processing contents of the control unit 115 of the wireless communication apparatus (master unit) 11 and the control unit 125 of the wireless communication apparatus (slave unit) 12 are different from those of the first embodiment, the processing contents of each control unit will be described in detail.

  The wireless communication device (master device) 11 and the wireless communication devices (slave devices) 12 and 13 in the present embodiment periodically change to the communication wireless channel stored in the storage unit 116, so that the In response to this, the channel is automatically changed. Also, for communication corresponding to the time zone based on the time change of the electric field strength obtained by the radio communication device (master unit) 11 and the radio communication devices (slave units) 12 and 13 intermittently measuring the electric field strength. It also has a function of determining a wireless channel and updating a list of communication wireless channels stored in the storage unit 116.

  These two functions can be switched between enabled and disabled by user operation.

  A channel setting process executed by the control unit 11 of the wireless communication apparatus (master unit) 11 will be described with reference to the flowchart of FIG. The flowchart of FIG. 8 starts when the function of automatically changing the channel according to the time zone is enabled.

  First, the control unit 115 of the wireless communication apparatus (master unit) 11 reads the current time and determines whether the current time is the channel change time (steps S401 and S402). Here, the channel change time is a time for changing a channel stored in the storage unit 116 in advance, and is, for example, every hour.

  If the channel change time is not reached in step S402 (step S402; No), the channel is not changed and the process proceeds to step S406. On the other hand, when the current time is the channel change time (step S402; Yes), the communication radio channel stored corresponding to the channel change time at this time is read from the storage unit 116 (step S402). S403). Here, the initial value stored in advance in the storage unit 116 is used before the communication radio channel is determined and stored by performing electric field strength measurement which will be described later.

  Then, information on the wireless channel for communication is transmitted to the wireless communication devices (slave devices) 12 and 13 (step S404), and the channel of the wireless circuit 112 of the wireless communication device (parent device) 11 is used for the communication. A wireless channel is set (step S405).

  Through the processes in steps S401 to S405, the communication radio channel stored in the storage unit 116 can be automatically changed periodically. Thereafter, the process proceeds to step S406, and a process of updating the list of communication wireless channels stored in the storage unit 116 is performed.

  In step S406, it is determined whether or not the function of updating the list of communication radio channels corresponding to the time zone stored in the storage unit 116 is enabled. The switching of the validity / invalidity of this function may be performed by the user operating the operation unit 117, or may be validated when a preset date / time is reached.

  If this function is disabled in step S406, the process proceeds to step S415. On the other hand, if this function is enabled, the processing after step S407 is performed.

  The control unit 115 of the wireless communication device (base unit) 11 determines that the current time is the time stored in advance in the storage unit as the electric field strength measurement time in step S407 (step S407; Yes). Reads a channel usable in this system from the storage unit 116 (step S408), and proceeds to step S409. On the other hand, if the current time is not the measurement time of the electric field strength, the process proceeds to step S415.

  In step S409, the control unit 115 controls the transmission circuit of the wireless circuit 112 so as to transmit a wireless signal including information requesting electric field strength measurement to the wireless communication devices (child devices) 12 and 13 (step S409). S102). At this time, the information requesting electric field strength measurement includes measurement conditions such as the channel frequency of the radio channel to be measured, the measurement time, and the number of measurements.

  Next, the control unit 115 measures the electric field strength of each channel based on the read channel information (step S410). Specifically, control is performed so that the receiving unit of the radio circuit 112 extracts an electric signal in a frequency band corresponding to each radio channel to be measured. In addition, the electric field strength measuring unit 113 controls the electric field strength measuring unit 123 so that the electric field strength measuring unit 113 measures the electric field strength in accordance with the extraction timing of the electric signal and outputs the measured value. When the control unit 115 acquires the measurement value of each channel from the electric field intensity measurement unit 113, the control unit 115 compares it with a preset threshold value.

  The measurement of the electric field strength and the comparison with the threshold value are repeated a plurality of times. And the frequency | count that the electric field strength exceeded the threshold value for every radio channel for communication is counted. As for the number of measurements, for example, assuming that the communication of another system existing in the vicinity has a transmission time of 100 msec and a transmission interval of 1000 msec, it is considered that the presence of the other system can be detected with 10 or more measurement times. The number of times exceeding the threshold counted for each channel is stored in the storage unit 116.

  The wireless communication devices (slave devices) 12 and 13 that have received the electric field strength measurement request from the wireless communication device (parent device) 11 measure the electric field strength and then transmit the measurement information to the wireless communication device (parent device) 11. Therefore, the control unit 115 acquires measurement information from the data signal received via the wireless circuit 112 and the data communication unit 114 (step S411). The control unit 115 stores the acquired result in the storage unit 116.

  The control unit 115 adds the number of times that the measured electric field strength value acquired in steps S409 and S410 and stored in the storage unit 116 exceeds the threshold for each channel. A channel having this value of 0 is determined as a free channel (step S412), and a communication radio channel to be used is determined from the free channels (step S413). The method for determining the communication radio channel to be used may be, for example, the channel with the smallest channel number among the empty channels, the channel with the largest channel number, or may be selected at random. If there is no empty channel, for example, the channel having the smallest total number of times that the measured value of the electric field intensity exceeds a preset threshold value is set.

  The control unit 115 stores the determined communication radio channel information in the storage unit 115 in association with the channel change time based on the current time (step S414).

  Through the processes in steps S407 to S414 described above, the list of communication wireless channels corresponding to the time zone stored in the storage unit 116 can be updated.

  Thereafter, the process proceeds to step S415, where it is determined whether or not the function of automatically changing the channel according to the time zone has been turned off by a user operation or the like. If not, the process returns to step S401 to perform processing. Continue.

  The control unit 125 of the wireless communication apparatus (child device) 12 starts the channel setting process shown in the flowchart of FIG. 9 after performing the initial setting. Other slave devices such as the wireless communication device (slave device) 13 perform the same processing as the wireless communication device (slave device) 12.

  The control unit 125 of the wireless communication device (child device) 12 determines whether a request for electric field strength measurement has been received from the wireless communication device (parent device) 11 (step S501). If a request has been received (step S501: Yes), the process proceeds to step S502, and if no request has been received, the process proceeds to step S504.

  The request for electric field strength measurement received by the wireless communication device (child device) 12 from the wireless communication device (parent device) 11 includes information such as the channel frequency for measuring the electric field strength, the measurement time, and the number of measurements. 125 controls the electric field strength measuring unit 123 to measure the electric field strength in accordance with the request (step S502). Specifically, control is performed so that the reception unit of the radio circuit 122 extracts an electric signal in a frequency band corresponding to each radio channel to be measured. In addition, the electric field intensity measurement unit 123 controls the electric field intensity measurement unit 123 so that the electric field intensity measurement unit 123 performs electric field intensity measurement in accordance with the extraction timing of the electric signal and outputs the measurement value. When the control value of each channel is acquired from the electric field strength measurement unit 123, the control unit 125 compares the measured value with a preset threshold value.

  The measurement of the electric field strength and the comparison with the threshold value are repeated a plurality of times. And the frequency | count that the electric field strength exceeded the threshold value for every radio channel for communication is counted.

  When the counting of the number of times that the electric field strength exceeds the threshold is completed, the control unit 125 transmits the counting result as electric field strength measurement information from the wireless circuit 122 to the wireless communication device (parent device) 11. The transmission of the electric field strength measurement information is performed as a response to the request from the wireless communication device (parent device) 11 (step S503).

  Thereafter, it is determined whether or not information including a communication wireless channel used in the wireless communication system 1 determined by the wireless communication device (parent device) 11 has been received from the parent device (step S504). When the communication wireless channel information is received, the control unit 125 changes the communication wireless channel of the wireless circuit 122 to the notified channel (step S505). The wireless circuit 112 wirelessly communicates with the wireless communication device (parent device) 11 and other child devices using the notified communication wireless channel.

  Thereafter, in step S506, it is determined whether or not the function for automatically changing the channel is turned off by a user operation or the like. If not, the process returns to step S501 and the processing is continued.

  As described above, the wireless communication system 1 according to the present embodiment includes the measurement information of the electric field strength measured by the wireless communication device (parent device) 11 and the electric field strength measured by the wireless communication devices (child devices) 12 and 13. The communication wireless channel is determined based on the measurement information, the communication wireless channel list corresponding to the time zone stored in the storage unit 116 is updated, and the communication wireless channel list is updated based on the communication wireless channel list. Since the radio channel for communication is automatically changed for each band, it is possible to select a radio channel for communication that is less affected by other systems according to the time zone. Good communication is possible.

  As described above, the wireless communication system according to the present invention performs electric field strength measurement in the wireless communication device (master device) and at least one wireless communication device (slave device), and is based on the obtained field strength measurement information. Since the communication wireless channel is determined, communication using the communication wireless channel with less influence of other systems is possible in the entire wireless communication system. In addition, efficient and high-quality wireless communication is possible.

  In addition, this invention is not limited to the said embodiment, Of course, the various change in the range which does not deviate from the summary of this invention is possible.

  For example, in the first and second embodiments, the electric field strength measurement is performed on a channel that can be used by the wireless communication device. Good. For example, the channel to be measured is specified as a measurement parameter in step S102 or step S103. When the number of channels to be measured is reduced, the time required for measurement can be shortened.

  In addition, the determination is made based on the measurement information of the electric field strength included in the information received from the wireless communication devices (slave devices) 12, 13, etc., but for all the wireless communication devices (slave devices) belonging to the wireless communication system 1. The communication radio channel to be used may be the same or different. For example, in FIG. 1, when determining a wireless channel for communication between the wireless communication device (parent device) 11 and the wireless communication device (child device) 12, the wireless communication device (parent device) 11 and the wireless communication device (child device) ) Extract empty channels from the 12 pieces of measurement information, and select a wireless channel for communication from them. On the other hand, when determining a wireless channel for communication between the wireless communication device (parent device) 11 and the wireless communication device (slave device) 13, the wireless communication device (parent device) 11 and the wireless communication device (slave device) 13 An empty channel is extracted from the measurement information, and a communication radio channel is selected from the extracted empty channel. Thereby, even when there is no empty channel in the entire system, a local empty channel can be selected as a communication radio channel.

  In the first and second embodiments, when the wireless communication devices (slave devices) 12 and 13 measure the electric field strength and then notify the measurement information according to a request from the wireless communication device (parent device) 11. However, the wireless communication devices (slave devices) 12, 13 and the like may voluntarily notify after measuring the electric field strength.

  In the first and second embodiments, the field strength measurement information by the field strength measurement unit 113 of the wireless communication device (base unit) 11 stored in the storage unit 116, the wireless communication device (slave unit) 12 or the like is received. The field strength measurement information of the wireless communication device (slave unit) 12 is the result of counting the number of times the field strength measurement value exceeds a preset threshold for each channel, but the field strength measurement value itself or The maximum value or average information of the measurement values may be used, or the communication frequency or communication time of the wireless communication system 1 may be used. In addition, the electric field strength is obtained by measuring VSSI in each wireless channel, but the measurement method is not limited to this, and any measurement method may be used.

  In the first embodiment, the configuration for setting the wireless channel for communication when the system is started up such as when the power is turned on has been described. However, the electric field strength is periodically measured even after the system is operated. The communication wireless channel may be updated. As a result, it is possible to dynamically change the communication radio channel in response to changes in the radio wave environment even after the radio communication system is started up, avoiding interference by other newly installed systems, and improving efficiency. Communication can be maintained.

  In the first embodiment, the electric field strength measurement is performed almost simultaneously in the wireless communication device (master device) 11 and the wireless communication device (slave device) 12. However, the timing of the electric field strength measurement is arbitrarily determined. Alternatively, a configuration may be adopted in which the slave unit is measured based on the result measured by the master unit. As a result, the number of channels measured by the wireless communication device (child device) can be reduced, and the processing amount and the data capacity for wireless communication can also be reduced.

  In Embodiment 1 described above, the example in which the measurement of the electric field strength in the wireless communication apparatus (child device) is performed 10 times has been described, but the number of times of measurement is arbitrary and may be one. For example, there is a method of setting the number of times of measurement as a measurement parameter in step S102 or step S103, which may be the same for all wireless communication devices or may be different for each wireless communication device. When the number of measurements is one, a channel whose electric field intensity does not exceed a preset threshold value is selected, and the processing can be simplified. On the other hand, if measurement is performed multiple times, the probability of detecting communications of other systems that operate intermittently that could not be detected in one measurement increases, and more accurately reflects the radio wave environment around the wireless communication device. it can.

  Further, in the second embodiment, the electric field strength measurement is performed at the measurement time stored in the storage unit, but the measurement time and the measurement period are arbitrary. The measurement period is, for example, one day. As a result, the channel usage status in each time zone of the day can be known in more detail, and communication can be performed while avoiding the time zone when the communication frequency of other systems is high.

1, 2, 3 Wireless communication system 11 Wireless communication device (base unit)
12, 13 Wireless communication device (slave unit)
21, 22, 31, 32 Wireless communication device 111, 121 Antenna 112, 122 Wireless circuit 113, 121 Field strength measuring unit 114, 124 Data communication unit 115, 125 Control unit 116, 126 Storage unit 117, 127 Operation unit 118, 128 Display section

Claims (11)

Wireless communication means for transmitting and receiving wireless signals to and from other wireless communication devices using a predetermined communication wireless channel selected from a plurality of wireless channels;
Electric field strength measuring means for measuring electric field strength in each of the plurality of wireless channels;
Measurement information acquisition means for acquiring measurement information indicating the electric field strength in each of the wireless channels measured by the other wireless communication device from information received by the wireless communication device from the other wireless communication device;
Based on the electric field strength in each of the radio channels measured by the electric field strength measurement means and the electric field strength in each of the radio channels indicated by the measurement information acquired by the measurement information acquisition means, the predetermined communication radio A radio channel determining means for determining a channel;
Wireless communication control means for controlling the wireless communication means to transmit and receive wireless signals to and from the other wireless communication device using the communication wireless channel determined by the communication wireless channel determination means;
A wireless communication apparatus comprising: Measurement request information transmission control means for transmitting, via the wireless communication means, measurement request information for requesting measurement of electric field strength in each of the wireless channels to the other wireless communication device,
The measurement information acquired by the measurement information acquisition means is the electric field intensity measured based on the measurement request information by the other wireless communication device that has received the measurement request information transmitted by the measurement request information transmission control means. Is sent information indicating
The wireless communication apparatus according to claim 1. The wireless communication control means includes
A communication radio channel information transmission unit that transmits information specifying the predetermined communication radio channel determined by the communication radio channel determination unit to the other radio communication device via the radio communication unit;
A radio channel setting means for setting a radio channel used by the radio communication means to the predetermined radio channel for communication;
The wireless communication apparatus according to claim 1, further comprising: The communication radio channel determination means determines, as the predetermined communication radio channel, a radio channel whose electric field intensity measured by the radio communication device and the other radio communication device does not exceed a preset threshold value.
The wireless communication device according to claim 1, wherein the wireless communication device is a wireless communication device. The communication radio channel determination means determines the radio channel having the smallest number of times that the electric field strength measured a plurality of times by the radio communication device and the other radio communication device exceeds a preset threshold value as the predetermined communication radio channel. As determined,
The wireless communication device according to claim 1, wherein the wireless communication device is a wireless communication device. After a predetermined time after the wireless communication means performs transmission / reception of a wireless signal using the predetermined communication wireless channel,
The electric field strength in each of the wireless channels measured by the electric field strength measuring means, and the electric field strength in each of the wireless channels measured by the other wireless communication device indicated by the measurement information acquired by the measurement information acquiring means. A communication wireless channel updating unit for updating the communication wireless channel based on the communication wireless channel;
The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus is a wireless communication apparatus. The electric field strength measured in the plurality of time zones by the electric field strength measuring means and the measurement information acquired by the measurement information acquiring means indicated by the other radio communication devices indicated in the plurality of time zones. Based on the measured electric field strength in each radio channel, the communication radio channel changing means for changing the communication radio channel for each of the plurality of time zones is further provided.
The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus is a wireless communication apparatus. The communication radio channel determination means uses the measurement information of the electric field strength acquired from the information transmitted from each of the other radio communication devices when the measurement information acquisition means has a plurality of other radio communication devices. On the basis of the wireless channel for communication for each wireless communication device,
The wireless communication device according to claim 1, wherein the wireless communication device is a wireless communication device. A wireless communication system comprising a plurality of wireless communication devices,
Each wireless communication device
Wireless communication means for transmitting and receiving wireless signals to and from other wireless communication devices using a predetermined communication wireless channel selected from a plurality of wireless channels;
Electric field strength measuring means for measuring electric field strength in each of the plurality of radio channels,
The first wireless communication device selected from the plurality of wireless communication devices is
Measurement information acquisition for acquiring, from information received by the wireless communication unit of the first wireless communication device from the other wireless communication device, measurement information indicating the electric field strength in each wireless channel measured by the other wireless communication device. Means,
Based on the electric field strength in each of the wireless channels measured by the electric field strength measuring means of the first wireless communication device and the electric field strength in each of the wireless channels indicated by the measurement information acquired by the measurement information acquiring means. Communication wireless channel determining means for determining the predetermined communication wireless channel,
Each of the plurality of wireless communication devices transmits and receives a wireless signal between the plurality of wireless communication devices using the predetermined communication wireless channel determined by the communication wireless channel determination means. Control communication means,
A wireless communication system. A wireless communication control method for transmitting and receiving wireless signals using a predetermined communication wireless channel selected from among a plurality of wireless channels between a plurality of wireless communication devices,
An electric field strength measuring step for measuring an electric field strength in each of the plurality of wireless channels;
A measurement information acquisition step for acquiring measurement information indicating the electric field strength in each of the wireless channels measured by the other wireless communication device from information received from the other wireless communication device;
Based on the electric field strength in each of the radio channels measured in the electric field strength measurement step and the electric field strength in each of the radio channels indicated by the measurement information acquired in the measurement information acquisition step, the predetermined communication radio A communication radio channel determination step for determining a channel;
A wireless communication control step for controlling to perform transmission and reception of wireless signals with the other wireless communication device using the predetermined communication wireless channel determined in the communication wireless channel determination step;
A wireless communication control method comprising: On the computer,
Electric field strength measurement procedure for measuring electric field strength in each of a plurality of wireless channels;
Measurement information acquisition procedure for acquiring measurement information indicating the electric field strength in each of the radio channels measured by the other radio communication device from information received from the other radio communication device;
Based on the field strength in each of the wireless channels measured in the field strength measurement procedure and the field strength in each of the wireless channels indicated by the measurement information acquired in the measurement information acquisition procedure, the other wireless communication device A communication radio channel determination procedure for determining a radio channel to be used for communication with a communication radio channel;
A wireless communication control procedure for controlling to perform transmission and reception of wireless signals with the other wireless communication device using the communication wireless channel determined in the communication wireless channel determination procedure;
A program for running

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